The impact of body mass index on direct to implant and two-stage immediate breast reconstruction procedure: a systematic review
Review Article

The impact of body mass index on direct to implant and two-stage immediate breast reconstruction procedure: a systematic review

Emma Bolette Odgaard ORCID logo, Nicolai Lassen Frid, Elisabeth Lauritzen, Tine Engberg Damsgaard

Department of Plastic Surgery and Burns Treatment, Rigshospitalet and Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark

Contributions: (I) Conception and design: EB Odgaard, TE Damsgaard; (II) Administrative support: EB Odgaard, TE Damsgaard; (III) Provision of study materials or patients: All authors; (IV) Collection and assembly of data: EB Odgaard; (V) Data analysis and interpretation: EB Odgaard; (VI) Manuscript writing: All authors; (VII) Final approval of manuscript: All authors.

Correspondence to: Emma Bolette Odgaard, MD. Department of Plastic Surgery and Burns Treatment, Rigshospitalet and Institute of Clinical Medicine, University of Copenhagen, Blegdamsvej 9, DK-2100 Copenhagen, Denmark. Email: emmaodgaard@gmail.com.

Background: Breast cancer (BC) is the most common cancer among women with a 90% 5-year survival rate. Thirty percent undergo a mastectomy, but only half of them receive a breast reconstruction (BR). Women with a high body mass index (BMI) are often not eligible for reconstructive surgery due to an increased risk of complications even though a BR improve women’s quality of life, and the risk of complications may be reduced with refined surgical techniques. Implant-based breast reconstruction (IBR) is one of the more frequently performed breast reconstructive procedures. The aim of this systematic review is to gather the current clinical evidence in order to provide an in-depth update to support clinical decision making. Thus, the association between BMI and postoperative complication rates after direct to implant (DTI) and 2-stage immediate IBR are investigated.

Methods: PubMed and EMBASE were searched. Studies specifying complications according to BMI following implant-based reconstruction within the last 10 years were included and assessed with PRISMA guidelines. Data on postoperative complications and patient characteristics were extracted and stratified into two groups according to World Health Organization (WHO)’s BMI classifications of non-obese (BMI <30 kg/m2) and obese (BMI ≥30 kg/m2). Complications were pooled into three categories: implant removal, minor and major complications. Pearson’s chi-square test or Fisher’s exact test and odds ratio were performed to evaluate any significant differences among the BMI groups.

Results: Of 3,492 screened studies, 27 met the inclusion criteria and were included for analysis. A total of 7,302 patients and 7,702 breasts were included in analyzing postoperative complications among the BMI <30 kg/m2 compared to the BMI ≥30 kg/m2. The analysis showed a significantly higher rate of minor- and major complications and implant removal among the BMI ≥30 kg/m2 group.

Conclusions: An increased risk of minor and major complications was found among the group with a BMI ≥30 kg/m2 for both reconstruction types. Thus, this systematic review may provide the clinician with higher-evidence data to support counseling strategies for BR and share the decision process with patients, when providing patients with individualized BR. Future studies could focus on investigating complications within smaller BMI groups.

Keywords: Breast reconstruction (BR); body mass index (BMI); postoperative complications; implant-based breast reconstruction (IBR)

Received: 18 October 2023; Accepted: 11 April 2024; Published online: 01 July 2024.

doi: 10.21037/abs-23-73

Highlight box

Key findings

• This review found an increased risk of major—and minor complications and implant removal within the body mass index (BMI) ≥30 kg/m2 population when compared to the BMI <30 kg/m2. This knowledge can be used to proper consult our patients and select the right patient for the optimal surgical procedure by shared decision-making and individualized breast reconstruction (BR).

What is known and what is new?

• Multiple studies have found an association between a high BMI and an increased complication rate. A BMI ≥30 kg/m2 is therefore often used as an exclusion criterion for receiving a breast reconstructive procedure. This study has gathered the clinical applied knowledge into a publication which give us a high-evidence-based knowledge for use in our clinical decision making. It confirms on a higher evidence level a higher risk of complications among patients with a BMI ≥30 kg/m2.

What is the implication, and what should change now?

• This review finds a higher incidence of minor and major complications and implant removal among patients with a BMI ≥30 kg/m2. This knowledge can be used to proper consult our patients and select the right patient for the optimal surgical procedure by shared decision-making and individualized BR. However, it does not differentiate between the different obese BMI groups.

Introduction

Breast cancer (BC) is the most common diagnosed cancer among women (1,2). In 2020, more than 2.3 million women were diagnosed globally (2,3). Survival rates have risen tremendously due to early detection and improved multidisciplinary treatment. In the US the 5-year survival rate is 90% for all stages of BC, resulting in an increased interest in BR surgery among these women (4).

In 2016, 34% (stage I and II), 68% (stage III) and 10% (stage IV) of BC patients received a mastectomy (2). Of these, only 56% underwent reconstructive surgery, even though studies have found, that breast reconstructive surgery improves quality of life, such as improved self-esteem, body image and psychological-, psychosocial- and sexual wellbeing (5-7).

Though the positive effects of reconstruction are comprehensive, not all women are eligible for reconstructive surgery. Obesity is frequently considered a contraindication for reconstructive surgery due to a higher prevalence of life-style diseases such as diabetes and cardiovascular diseases (1,6,8,9). Additionally, there is a potential increased risk of post-operative complications, including loss of reconstruction, infections, delayed wound healing, necrosis, seroma and hematoma (10).

The global burden of obesity in women is growing. In 2016, 40% of women were classified as overweight and 15% were classified as obese (8). Obese women are more prone to develop BC, and due to the current increase in global obesity this may add to an increased number of women being diagnosed with BC, and subsequently undergoing mastectomy (11). As obesity is considered a relative contraindication for BR, a large number of women may not be found eligible for reconstructive surgery following their mastectomy (9).

The current breast reconstructive procedures consist of either implant-based, autologous or a combination of both. Implant-based breast reconstruction (IBR) accounts for almost 70% of all reconstructions (12,13). An IBR can be performed as an immediate or delayed procedure, comprising a 1-stage direct-to-implant (DTI) or 2-stage with tissue expander and later exchange to a fixed-size implant (13).

There has not been published a high evidence level paper which summarizes complications rates among different body mass index (BMI) groups within the last couple of years and current clinical decision making is based in lesser quality studies.

Further does many studies not differentiate between the different BR types and study groups are often being homogenized, which challenging good individualized patient consulting.

The aim of this review is to gather the clinical applied knowledge into a publication which give us a high-evidence-based knowledge for improved clinical decision making by investigate the association between BMI and postoperative complication rates after IBR following mastectomy. We present this article in accordance with the PRISMA reporting checklist (available at https://abs.amegroups.com/article/view/10.21037/abs-23-73/rc).

Methods

Search strategy

A systematic review of the current literature on BMI and postoperative complications following IBR was performed. All papers stating complications for a specific BMI or a BMI <30 or ≥30 kg/m2 were included.

A systematic search was performed using PubMed and EMBASE using the following words; “BMI” OR “body mass index” OR “obesity” OR “obese” AND “mammaplast*” OR “breast reconstruction” OR “implant-based reconstruction” OR “breast implant reconstruction” OR “breast implants” AND “complication” OR “postoperative” OR “outcome*” OR “treatment outcome”. The latest searches on PubMed and EMBASE were performed at the beginning of December 2022.

Inclusion criteria

The inclusion criteria were: studies published in English within the last 10 years investigating complications following implant-based DTI and 2-stage BR and stratified according to BMI. Studies investigating immediate- and/or delayed reconstruction, DTI and/or 2-stage reconstruction and therapeutic- and/or prophylactic mastectomies were all included.

Exclusion criteria

Studies were excluded during the first screening if they only contained information about autologous breast reconstruction (BR), gender reassignment, only augmentation, only mastectomy, or only breast conserving surgery. Studies were excluded during the second screening if the patients and complications were not stratified according to WHO’s BMI classification or if the specific BMI was not mentioned for each complication. Studies were also excluded if complications were not specified or not stratified according to the breast reconstructive method i.e., IBR (Figure 1).

Figure 1 PRISMA flow chart. Pts, patients; BMI, body mass index; WHO, World Health Organization.

Outcome measures

The primary outcome measures were the complication rates i.e., minor and major complications and implant removal. Complications were extracted from the included studies as either per breast or per patient depending on how the data was reported.

Complications were pooled into minor complications, major complications and implant removal. Minor complications were defined as complications treated conservatively encompassed capsular contracture, epidermolysis of the skin flap, seroma, delayed wound healing, wound dehiscence, infections treated with antibiotics and infections not further specified. Major complications were defined as complications requiring surgical intervention and encompassed exposure of implant, rupture of implant, infections, necrosis and hematoma, deep venous thrombosis and pulmonary embolism.

Implant removal included explantation resulting in exchange for a new implant or loss of reconstruction. Implant removal was defined as such as many of the studies did not clearly state the consequence of implant removal. Even though implant removal is a major complication, a separate analysis for implant removal was performed, as this will add more information on the most dreaded complication—removal of the implant and consequently loss of reconstruction.

Patient, reconstructive and study characteristics

Patient, reconstructive and study characteristics were extracted from the studies as either per breast or per patient based on data provided in the included papers. The extracted patient information included BMI, age, smoking status and whether the patient had diabetes. The BR characteristics included reconstruction type, use of acellular dermal matrix (ADM) and radiotherapy. Study characteristics follow-up time, study design and level of evidence.

Study selection

The search resulted in 3,492 studies. One thousand and thirty-four duplicates were removed using Covidence resulting in 2,458 studies. One thousand eight hundred and twenty-eight studies were removed during titles and abstracts screening. Of the 630 studies left, 118 papers were not retrievable. Thus, 512 full text articles were screened, of which 27 articles met the inclusion criteria (Table 1 and Figure 1).

Table 1

Summary of included studies and data

Authors, year Country/region Study design LE DTI or 2-stage Summary of data included in BMI <30 vs. ≥30 kg/m2
BMI (kg/m2) N Minor Minor (%) Major Major (%) Implant removal Implant removal (%)
Complications per breast
   Banuelos et al., 2020 (14) USA Rc 3 2-stage ≥30 336 55 16 19 8 24 7
Total 336 55 16 19 8 24 7
   Basu et al., 2013 (15) UK (England) Pc-c 4 DTI ≥30 20 2 10 0 0 0 0
Total 20 2 10 0 0 0 0
   Becker et al., 2019 (16) USA Rc-c 3 DTI <30 20 7 35 0 0 0 0
≥30 6 2 33 0 0 1 17
Total 26 9 35 0 0 1 4
   Bernini et al., 2022 (17) Italy Rc 3 Both <25 114 NA NA NA NA 5 36
Total 114 NA NA NA NA 5 83
   Casella et al., 2015 (18) Italy Pc 2 2-stage <25 25 6 24 1 4 0 0
Total 25 6 24 1 4 0 0
   De Vita et al., 2017 (19) Italy Rc 3 Both <30 2,023 NA NA 115 6 91 4
Total 2,023 NA NA 115 6 91 4
   Gabriel et al., 2020 (20) USA Rc 3 2-stage ≥30 257 99 39 9 4 4 2
Total 257 99 39 9 4 4 2
   Gunnarsson et al., 2018 (21) Norway and Denmark Pc-c 4 DTI <30 43 1 2 3 7 0 0
≥30 4 0 0 0 0 0 0
Total 47 1 2 3 6 0 0
   Hallberg et al., 2018 (22) Sweden Rc-c 3 Both <30 65 11 17 2 3 2 3
Total 65 11 17 4 6 2 3
   Kamel et al., 2019 (23) USA Rc 3 2-stage ≥30 110 13 12 18 16 2 2
Total 110 13 12 18 16 2 2
   Kanuri et al., 2014 (24) USA Rc 3 2-stage <30 602 63 10 NA NA 3 0
≥30 108 16 15 NA NA 4 4
Total 709 79 11 NA NA 7 1
   Lovecchio et al., 2015 (25) USA Rc 3 2-stage <30 1,639 296 13 36 9 141 7
Total 1,639 296 13 36 9 141 7
   Luce et al., 2015 (26) USA Rc 3 2-stage >35 67 52 78 NA NA 13 19
Total 67 52 78 NA NA 13 19
   Nahabedian et al., 2017 (27) USA Rc 3 Both <30 121 12 10 4 3 8 7
≥30 24 1 4 0 0 2 8
Total 141 13 9 4 3 10 7
   Nguyen et al., 2014 (28) USA Rc 3 2-stage <30 376 75 20 12 3 45 12
≥30 175 52 30 8 5 26 15
Total 551 127 23 20 4 71 13
   Payne et al., 2022 (29) USA Rc 3 2-stage <30 86 13 15 7 8 20 23
≥30 50 18 36 8 16 26 52
Total 136 31 23 15 11 46 34
   Sou et al., 2022 (30) Taiwan Rc 3 DTI <30 30 22 73 10 33 0 0
Total 30 22 73 10 33 0 0
   Wilson et al., 2015 (31) USA Rc-c 4 2-stage <30 10 0 0 1 10 1 10
≥30 6 1 17 1 17 2 33
   Woo et al., 2016 (32) Korea Rc 3 2-stage ≥30 397 14 4 53 17 15 4
Total 397 14 4 53 17 15 4
   Yuen et al., 2014 (33) USA Rc 3 Both <30 109 17 16 6 6 3 3
≥30 87 56 64 26 30 10 11
Total 196 73 37 33 17 13 7
   Yuen et al., 2017 (34) USA Rc 3 Both <30 66 37 56 7 11 2 3
≥30 65 57 88 14 22 8 12
Total 131 94 72 21 16 10 8
Complications per woman
   De Vita et al., 2017 (19) Italy Rc 3 Both <30 1,647 283 17 159 10 NA NA
Total 1,647 283 17 159 10 NA NA
   Hadad et al., 2015 (35) USA Rc 3 Both ≥30 66 5 8 22 33 10 15
Total 66 5 8 22 33 10 15
   Kachare et al., 2022 (36) USA Rc 3 2-stage ≥30 21 4 19 1 5 1 5
Total 21 4 19 1 5 1 5
   Ota et al., 2016 (37) Japan Rc 3 2-stage <30 213 18 8 NA NA NA NA
Total 213 18 8 NA NA NA NA
   Rothe et al., 2022 (38) Germany Rc 3 NA ≥30 15 7 47 NA NA NA NA
Total 15 7 47 NA NA NA NA
   Walker et al., 2021 (39) USA Rc 3 Both <30 53 11 24 2 4 NA NA
Total 53 11 21 2 4 NA NA
   Wink et al., 2014 (40) USA Rc 3 DTI <30 1,229 NA NA 97 8 NA NA
≥30 374 NA NA 47 13 NA NA
Total 1,603 – – 144 – – –

Outcome comparison between body mass index groups stratified according to ‘WHO classification’ and in ‘≥30 (obese) and <30 (non-obese)’. Outcome analyzed per woman and per breast. NA, not applicable/not announced; LE, level of evidence; Rc, retrospective cohort; Rc-c, retrospective case-control; Pc-c, prospective case-control; Pc, prospective cohort; Pcom, prospective comparative; DTI, direct to implant; 2-stage, 2-stage breast reconstruction; BMI, body mass index.

Statistical analysis

Data was extracted and analyzed as complication per breast or per patient depending on the availability in the included studies. The data was pooled into BMI <30 kg/m2 and BMI ≥30 kg/m2. Pearson’s chi-square test, Fischer’s exact test, odds ratio and 95% confidence interval were performed to evaluate the difference and any significant differences among the two groups. Statistical significance was set at P<0.05. Statistical analysis was performed using R version 4.2.2 and Microsoft Excel 10 version 22H2.

Risk of bias in individual studies

Level of evidence and strengthening the reporting of observational studies in epidemiology (STROBE) statement was used to assess the quality and bias of each individual study (41).

Results

Study selection

Of 2,458 screened studies, 27 met the inclusion criteria. Seven thousand three hundred and two patients and more than 7,700 breasts were included.

Patient characteristics

Patient characteristics are depicted in Tables S1-S3. The age ranged between 43 and 66 years and stated in 20 of the 27 studies (14-16,18,20-23,25-27,29,31-34,36,37,39,40). Five percent to ten percent of the patients were active smokers and 5–9% had diabetes mellitus. The characteristics for the analysis stating complication per breast (Table S2) showed a slight increase in smoking and radiotherapy among the BMI <30 kg/m2 study population and an increase in diabetes among the BMI ≥30 kg/m2 study population.

Reconstructive characteristics

Reconstructive characteristics are depicted in Table 1 and Tables S1-S3. Fourteen studies included only 2-stage procedures, 5 studies included only DTI procedures and 8 studies included both procedures. The majority of women received a 2-stage BR. ADM was used in 36% of the BR. The implants were placed in the pre-pectoral, sub-pectoral plane and in some cases the dual plane technique was applied.

Study characteristics

Twenty studies reported outcome per breast, 6 studies specified outcome per patient, and 1 study disclosed some outcomes per breast and others per patient. Two studies did not report minor complications, 5 studies lacked information on major complications and 5 studies did not include data on implant removal. Follow-up was reported in 22 studies. An estimate of the follow-up time was available for the authors to calculate in 4 of the 5 studies with missing information. Mean follow-up time ranged from 30 days to 65 months (15-34).

Level of evidence

Each included study was classified by level of evidence (42). No studies were of evidence level of I or II. Twenty-three studies were of evidence level III and level IV was represented by 4 studies (Table 1 and Figure 2).

Figure 2 The distribution of the evidence level among the included articles in the analysis. Level I: randomized controlled trial; Level II: prospective comparative studies; Level III: case control, retrospective comparative studies; Level IV: case series.

Risk of bias

The STROBE statement (41) was used for a systematic assessment and comparison of the included studies (Table S4). The majority (25 out of 27) of the articles were retrospective observational studies and therefore prone to recall- and observer bias. Methodological weaknesses were found in 14 studies: missing data on follow-up time and/or follow-up method and lack of specified selection criteria, minor and major complications. Eight studies had weakness in their results due to lack of baseline information. Weakness in the discussion were found in nine studies since the studies did not discuss their own limitations.

Study design

Two of the included studies reported prospectively collected data and another 25 of the papers described retrospectively acquired data (15,21) and 25 were retrospective reviewed (14,16-20,22-40). Twenty-two studies were cohort studies (14,17-20,23-30,32-40) and the remaining 5 papers reported results obtained from serial cases (15,16,21,22,31).

Analyses

Statistical analysis was performed on complications per breast and per patient to include all studies. The included breasts and patients were stratified in two subgroups i.e., BMI <30 kg/m2 and BMI ≥30 kg/m2. The groups were analyzed and compared in three different outcome measures: minor complications, major complications as well as removal of implant.

Analysis of complications per breast comparing obese (BMI ≥30 kg/m2) vs. non-obese (BMI <30 kg/m2)

When analyzing the complications per breast, the rate of minor complications (OR 2.9, 95% CI: 2.5–3.3, P<0.05), major complications (OR 4.7, 95% CI: 3.7–6.0, P<0.05) and implant removal implant removal (OR 1.4, 95% CI: 1.1–1.7, P<0.05) were significantly higher in the group of patients with a BMI ≥30 kg/m2, as illustrated in Figure 3 and Table 2.

Figure 3 The percentage of breast with minor complications, major complications and removal of implant following IBR pooled into BMI <30 kg/m2 and BMI ≥30 kg/m2. *, P<0.05. IBR, implant-based breast reconstruction; BMI, body mass index.

Table 2

Pooled outcome measurements for both DTI and 2-stage reconstruction comparing BMI ≥30 kg/m2 (obese) with BMI <30 kg/m2 (non-obese) per breast with odds ratios and P values

Per breast BMI (kg/m2) Minor Major Removal
c n OR (95% CI) P value c n OR (95% CI) P value c n OR (95% CI) P value
<30 560 (11%) 5,215 (75%) – – 114 (2%) 4,613 (75%) – – 321 (6%) 5,329 (76%) – –
≥30 442 (26%) 1,716 (25%) 2.9 (2.5–3.3) <0.05 164 (11%) 1,541 (25%) 4.7 (3.7–6.0) <0.05 137 (8%) 1,716 (24%) 1.4 (1.1–1.7) <0.05
Total 1,002 (14%) 6,931 1.4 (1.3–1.6) <0.05 278 (5%) 6,154 1.9 (1.5–2.3) <0.05 458 (7%) 7,045 1.1 (0.9–1.3) <0.05

DTI, direct to implant; BMI, body mass index; c, complication; OR, odds ratio; 95% CI, 95% confidence interval.

Three forest plots were made to compare rates of minor complications, major complications and implant removal and consist of the included studies with data on both BMI <30 kg/m2 and BMI ≥30 kg/m2 (Figures 4-6). The forest plot for minor complications shows that 5 of the 7 studies found an increased complication rate among the obese group (BMI ≥30 kg/m2) (Figure 4). The forest plot for major complications, comprising 5 studies, shows an increased risk of major complications among the BMI ≥30 kg/m2 for all 5 papers (Figure 5). The forest plot for implant removal consists of 7 studies, which all show an increased risk of implant removal among the BMI ≥30 kg/m2 (Figure 6). The combined data in each of the three forest plots shows an increased risk of minor complications, major complications and implant removal among the BMI ≥30 kg/m2.

Figure 4 Forest plot for minor complications per breast. The forest plot includes studies with data on both BMI <30 kg/m2 and BMI ≥30 kg/m2 on minor complications. The combined includes data from all the included studies in this review (16,24,27-29,33,34). BMI, body mass index; OR, odds ratio; 95% CI, 95% confidence interval.
Figure 5 Forest plot for major complications per breast. The forest plot includes studies with data on both BMI <30 kg/m2 and BMI ≥30 kg/m2 on major complications. The combined includes data from all the included studies in this review (28,29,31,33,34). BMI, body mass index; OR, odds ratio; 95% CI, 95% confidence interval.
Figure 6 Forest plot for removal of implant per breast. The forest plot includes studies with data on both BMI <30 kg/m2 and BMI ≥30 kg/m2 on removal of implant. The combined includes data from all the included studies in this review (24,27-29,31,33,34). BMI, body mass index; OR, odds ratio; 95% CI, 95% confidence interval.

Analysis of complications per patient comparing obese (BMI ≥30 kg/m2) vs. non-obese (BMI <30 kg/m2)

The per patient analysis (Table 3 and Figure 7) showed a significantly higher rate of major complications among the BMI ≥30 kg/m2 group (OR 2.0, 95% CI: 1.5–2.6, P<0.05) (Table 3). Patients with BMI ≥30 kg/m2 had a higher rate of implant removal (5% vs. 15%), but did not reach statistical significance, probably due to the small sample size (n=21 and n=66). There was not found a significant difference rate of minor complications.

Table 3

Pooled outcome measurements for both DTI and 2-stage reconstruction comparing BMI ≥30 kg/m2 (obese) with BMI <30 kg/m2 (non-obese) women with odds ratios and P values

Per pt BMI (kg/m2) Minor Major Removal
c n OR (95% CI) P value c n OR (95% CI) P value c n OR (95% CI) P value
<30 316 (16%) 1,934 (94.7%) – – 259 (9%) 2,950 (86%) – – 1 (5%) 21(24%) – –
≥30 20 (18%) 109 (5.3%) 1.2 (0.7–1.9) 0.67 74 (16%) 468 (14%) 2.0 (1.5–2.6) <0.05 10 (15%) 66 (76%) 3.6 (0.4–29.7) 0.38
Total 336 (16%) 2,043 1.0 (0.9–1.2) 0.69 333 (10%) 3,418 1.1 (0.9–1.2) <0.05 11 (13%) 87 2.9 (0.4–23.8) 0.83

DTI, direct to implant; BMI, body mass index; pt, patient; c, complication; OR, odds ratio; 95% CI, 95% confidence interval.

Figure 7 The percentage of patients who experienced minor complications, major complications and removal of implant after IBR pooled into BMI <30 kg/m2 and BMI ≥30 kg/m2. The number of major complications was higher in the BMI ≥30 kg/m2 group. IBR, implant-based breast reconstruction; BMI, body mass index. *, P<0.05.

Only one included article in complications per patient contains information on both BMI groups. Thus, a forest plot could not be provided.

Subgroup analysis of complications per breast comparing DTI with 2-stage within BMI <30 kg/m2 and BMI <30 kg/m2

The subgroup analyses comparing the two different reconstruction types within the same BMI-group were only performed for complication per breast due to lack of data availability among studies mentioning complications per patient. The subgroup analysis does not include data from all the included studies because the majority of the studies did not specify the complication for the specific reconstruction type even if the study was composed of both DTI and 2-stage BR.

The analysis (Table 4) showed favorable results for 2-stage reconstruction among the BMI <30 kg/m2. It showed a significantly higher complication rate within the BMI <30 kg/m2 of minor complications (OR 2.2, 95% CI: 1.4–3.5, P<0.05) and major complications (OR 5.4, 95% CI: 2.9–10.3, P<0.05) within the DTI group when compared to the 2-stage BR group. It was not possible to compare the rate of implant removal within the BMI <30 kg/m2 due to lack of data. The analysis comparing the two different reconstruction options within the BMI ≥30 kg/m2 group showed no significant difference between the BR options in any of the outcome measurements.

Table 4

Pooled outcome measurements for BMI ≥30 kg/m2 (obese) with BMI <30 kg/m2 (non-obese) comparing DTI to 2-stage implant based breast reconstruction to odds ratios and P values

Per breast BMI <30 kg/m2 BMI ≥30 kg/m2
c n [%] OR (95% CI) P value c n [%] OR (95% CI) P value
Minor
   2-stage 490 2,804 [17] 381 1,575 [24]
   DTI 30 93 [32] 2.2 (1.4–3.5) <0.05 4 30 [13] 0.5 (0.2–1.4) 0.24
Major
   2-stage 64 2,202 [3] 137 1,400 [10]
   DTI 13 93 [14] 5.4 (2.9–10.3) <0.05 1 30 [3] 0.3 (0.0–2.4) 0.38
Removal
   2-stage 212 2,804 [8] 124 1,575 [8]
   DTI 0 93 [NA] NA (NA) <0.05 1 30 [3] 0.4 (0.01–3.0) 0.57

BMI, body mass index; DTI, direct to implant; c, complication; OR, odds ratio; 95% CI, 95% confidence interval; NA, not applicable/not announced.

Multiple other subgroup analyses were attempted, but could not be performed due to lack of available data resulting in small sample sizes and inconclusive results. These included comparison of specific complications, follow-up time and smaller BMI groups. The comparison of complication not divided into the three outcome measurements could not be performed because the included studies were very heterogenic, some only mentioning infections, some only mentioning implant removal and some mentioning many different complications. The comparison of follow up time was not possible either. A short follow up time was defined as <1 month and a long follow up time was defined as >1 month. Only 1 out of the 27 included studies had a short follow-up time, why this analysis was not possible. A subgroup analysis breaking up the groups of patients with BMI ≥30 kg/m2 (BMI 30–34.9 and >35 kg/m2), was not possible due to too small BMI-groups.

Discussion

This study aimed to investigate a possible association between BMI and postoperative complication rates after IBR. Complications were pooled into implant removal, minor and major complications and stratified according to WHO BMI classifications of obese and non-obese.

The per breast analysis (Table 2) comprised of both DTI and 2-stage BR showed significantly higher rates of minor and major complications and implant removal in the BMI ≥30 kg/m2 group. The per patient analysis (Table 3) only showed a significantly higher rate of major complications in the obese group. The study population in the per patient analysis was significantly smaller, especially in the analysis of minor and implant removal when compared to the per breast analysis. This could explain the difference between the two analyses, where there was not found significant difference between the BMI groups in risk of minor complications and risk of implant removal in the per patient analysis. The larger study populations favor the results from the per breast analysis.

A subgroup analysis was not possible to perform subgroup analysis of individual BMI groups in the obese population (BMI 30–34.9 kg/m2 and BMI >35 kg/m2) due to lack of studies including patients with a BMI >35 kg/m2. The lack of data on postoperative BR complications on patients with BMI >35 kg/m2 may be attributed to several factors. As surgeons adhere to current guidelines and indications for BR, patients with BMI >35 kg/m2 will not be offered a BR. Additionally, studies including patients with BMI >35 kg/m2 undergoing BR will often not be published as the patient population will be small. Thus, BR in obese patients may only be performed in highly selected patients, as this requires extra considerations and precautions.

The findings of this review are comparable to previous studies. Weichman et al. (43) and Srinivasa et al. (44) with 577 and 1,625 patients found an increase in minor- and major complication rate among the BMI ≥30 kg/m2 study population. Srinivasa et al. also found an increase in minor- and major complication rate for every increase in BMI according to WHO BMI classification. Fischer et al. (45) and Pannucci et al. (46) studies combined included 23,554 patients found an increased risk of implant removal among the obese when compared to the non-obese (45,46). However, in contrast to this review, studies, Leitner et al. (47) analyzed 196 reconstructive breasts in 134 patients and did not find BMI associated with a significantly higher risk of minor and major complications and implant removal. This review found an increased rate of all three measurement outcomes in the BMI ≥30 kg/m2 group.Within the BMI <30 group 2-stage BR might serve as a better option due to lower minor and major complication rate. This knowledge can be used to properly consult our patients and select the right patient for the optimal surgical procedure by shared decision-making and individualized BR. Future studies should investigate complications within a more precise BMI which is not limited by the categorical data of the BMI classification to further improve patient counseling.

Strengths and limitations

This systematic review included a total of 7,302 patients and more than 7,702 breasts from 27 different studies, multiple different hospitals and surgeons. This limited the risk of single-surgeon and single-hospital bias. A large study population strengthened the analysis.

A separate analysis for implant removal adds to a more accurate study population and complication rate. Some of the included studies only contained information about implant removal and did not mention any other major complication and some studies mentioned ex major infections but did not mention implant removal. However, the majority of included studies did not disclose whether implant removal resulted in loss of reconstruction or exchange to a new tissue expander or permanent implant. This lack of information is important, as it is an essential detail in assessing the success of BR hereby hindering a comprehensive understanding of the outcome.

The BMI classification system is limited by its categorical data. Using BMI is a simple or rather undifferentiated measure. The BMI classification has some flaws. It does not consider different body types where muscle mass, bone density and age are not taken into account. However, it is validated by WHO and may be used as a standardized measure when comparing data from the included papers.

The included studies are of lower level of evidence, limiting the conclusions to be drawn from this review. However, this systematic review will provide the reader with a higher-level analysis of the current literature and may provide the surgeon with more substantial data, thus supporting and improving our patient counseling and decision making.

Conclusions

This study aimed to investigate the association between BMI and postoperative complications following immediate implant-based BR after mastectomy. The complication per breast analysis, based on 7,702 breasts, found an increased risk of major and minor complications as well as implant removal within the BMI ≥30 kg/m2 population when compared to the BMI <30 kg/m2.

These collected and analyzed data in this systematic review may provide us with higher level evidence and thus improve our patient counseling in selecting the right patient. However, it is unlikely that there will be a substantial increase in studies offering patients with a BMI ≥30 kg/m2 a BR since it requires extra considerations and precautions.

Acknowledgments

Funding: None.

Footnote

Reporting Checklist: The authors have completed the PRISMA reporting checklist. Available at https://abs.amegroups.com/article/view/10.21037/abs-23-73/rc

Peer Review File: Available at https://abs.amegroups.com/article/view/10.21037/abs-23-73/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://abs.amegroups.com/article/view/10.21037/abs-23-73/coif). T.E.D. serves as an unpaid editorial board member of Annals of Breast Surgery from July 2023 to June 2025. The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

  1. Regan JP, Casaubon JT. Breast Reconstruction. StatPearls. Published online September 4, 2021. Accessed May 9, 2022. Available online: https://www.ncbi.nlm.nih.gov/books/NBK470317/
  2. Sung H, Ferlay J, Siegel RL, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin 2021;71:209-49. [Crossref] [PubMed]
  3. WHO. Breast cancer. WHO. Published March 26, 2021. Accessed May 6, 2022. Available online: https://www.who.int/news-room/fact-sheets/detail/breast-cancer
  4. National Cancer Institute. SEER Survival Rates for Breast Cancer. Published 2021. Accessed May 6, 2022. Available online: https://www.cancer.org/cancer/breast-cancer/understanding-a-breast-cancer-diagnosis/breast-cancer-survival-rates.html
  5. Cordova LZ, Hunter-Smith DJ, Rozen WM. Patient reported outcome measures (PROMs) following mastectomy with breast reconstruction or without reconstruction: a systematic review. Gland Surg 2019;8:441-51. [Crossref] [PubMed]
  6. Nahabedian M. Overview of breast reconstruction - UpToDate. UpToDate - Wolters Kluwer. Published April 28, 2022. Accessed May 6, 2022. Available online: https://www.uptodate.com/contents/overview-of-breast-reconstruction
  7. Bellini E, Pesce M, Santi P, et al. Two-Stage Tissue-Expander Breast Reconstruction: A Focus on the Surgical Technique. Biomed Res Int 2017;2017:1791546. [Crossref] [PubMed]
  8. Tjeertes EK, Hoeks SE, Beks SB, et al. Obesity--a risk factor for postoperative complications in general surgery? BMC Anesthesiol 2015;15:112. Erratum in: BMC Anesthesiol 2015;15:155. [Crossref] [PubMed]
  9. Obesity and overweight. WHO. Published June 9, 2021. Accessed May 8, 2022. Available online: https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight
  10. Chen CL, Shore AD, Johns R, et al. The impact of obesity on breast surgery complications. Plast Reconstr Surg 2011;128:395e-402e. [Crossref] [PubMed]
  11. Engin A. Obesity-associated Breast Cancer: Analysis of risk factors. Adv Exp Med Biol 2017;960:571-606. [Crossref] [PubMed]
  12. Serletti JM, Fosnot J, Nelson JA, et al. Breast reconstruction after breast cancer. Plast Reconstr Surg 2011;127:124e-35e. [Crossref] [PubMed]
  13. Frey JD, Salibian AA, Karp NS, et al. Implant-Based Breast Reconstruction: Hot Topics, Controversies, and New Directions. Plast Reconstr Surg 2019;143:404e-16e. [Crossref] [PubMed]
  14. Banuelos J, Abu-Ghname A, Vyas K, et al. Should Obesity Be Considered a Contraindication for Prepectoral Breast Reconstruction? Plast Reconstr Surg 2020;145:619-27. [Crossref] [PubMed]
  15. Basu NN, Ross G. One stage breast reconstruction following prophylactic mastectomy for ptotic breasts: The inferior dermal flap and implant. European Journal of Surgical Oncology 2013;39:467. [Crossref]
  16. Becker H, Mathew PJ. Immediate Prepectoral Breast Reconstruction in Suboptimal Patients Using an Air-filled Spacer. Plast Reconstr Surg Glob Open 2019;7:e2470. [Crossref] [PubMed]
  17. Bernini M, Meattini I, Saieva C, et al. Pre-pectoral breast reconstruction: early and long-term safety evaluation of 146 unselected cases of the early pre-pectoral era of a single-institution, including cases with previous breast irradiation and post-mastectomy radiation therapy. Breast Cancer 2022;29:302-13. [Crossref] [PubMed]
  18. Casella D, Calabrese C, Bianchi S, et al. Subcutaneous Tissue Expander Placement with Synthetic Titanium-Coated Mesh in Breast Reconstruction: Long-term Results. Plast Reconstr Surg Glob Open 2015;3:e577. [Crossref] [PubMed]
  19. De Vita R, Zoccali G, Buccheri EM, et al. Outcome Evaluation after 2023 Nipple-Sparing Mastectomies: Our Experience. Plast Reconstr Surg 2017;139:335e-47e. [Crossref] [PubMed]
  20. Gabriel A, Sigalove S, Storm-Dickerson TL, et al. Dual-Plane versus Prepectoral Breast Reconstruction in High-Body Mass Index Patients. Plast Reconstr Surg 2020;145:1357-65. [Crossref] [PubMed]
  21. Gunnarsson GL, Thomsen JB. Prepectoral Hammock and Direct-to-implant Breast Reconstruction in 10 Minutes: A Focus on Technique. Plast Reconstr Surg Glob Open 2018;6:e1931. [Crossref] [PubMed]
  22. Hallberg H, Lewin R, Elander A, et al. TIGR(®) matrix surgical mesh - a two-year follow-up study and complication analysis in 65 immediate breast reconstructions. J Plast Surg Hand Surg 2018;52:253-8. [Crossref] [PubMed]
  23. Kamel GN, Mehta K, Nash D, et al. Patient-Reported Satisfaction and Quality of Life in Obese Patients: A Comparison between Microsurgical and Prosthetic Implant Recipients. Plast Reconstr Surg 2019;144:960e-6e. [Crossref] [PubMed]
  24. Kanuri A, Liu AS, Guo L. Whom should we SPY? A cost analysis of laser-assisted indocyanine green angiography in prevention of mastectomy skin flap necrosis during prosthesis-based breast reconstruction. Plast Reconstr Surg 2014;133:448e-54e. [Crossref] [PubMed]
  25. Lovecchio F, Jordan SW, Lim S, et al. Risk Factors for Complications Differ Between Stages of Tissue-Expander Breast Reconstruction. Ann Plast Surg 2015;75:275-80. [Crossref] [PubMed]
  26. Luce EA, Adams RL, Chandler RG, et al. Tissue Expander versus Tissue Expander and Latissimus Flap in Morbidly Obese Breast Reconstruction Patients. Plast Reconstr Surg Glob Open 2015;3:e323. [Crossref] [PubMed]
  27. Nahabedian MY, Cocilovo C. Two-Stage Prosthetic Breast Reconstruction: A Comparison Between Prepectoral and Partial Subpectoral Techniques. Plast Reconstr Surg 2017;140:22S-30S. [Crossref] [PubMed]
  28. Nguyen KT, Hanwright PJ, Smetona JT, et al. Body mass index as a continuous predictor of outcomes after expander-implant breast reconstruction. Ann Plast Surg 2014;73:19-24. [Crossref] [PubMed]
  29. Payne SH, Ballesteros S, Brown OH, et al. Skin Reducing Mastectomy and Immediate Tissue Expander Reconstruction: A Critical Analysis. Ann Plast Surg 2022;88:485-9. [Crossref] [PubMed]
  30. Sou WK, Perng CK, Ma H, et al. The Effect of Biological Scaffold (Biodesign) in Postmastectomy Direct-to-Implant Breast Reconstruction: A 5-Year Single-Institution Experience. Ann Plast Surg 2022;88:S92-8. [Crossref] [PubMed]
  31. Wilson HB. New Deep Dermal ADM Incorporates Well in Case Series of Complex Breast Reconstruction Patients. Medicine (Baltimore) 2015;94:e745. [Crossref] [PubMed]
  32. Woo KJ, Paik JM, Mun GH, et al. Risk Factors for Complications in Immediate Expander-Implant Breast Reconstruction for Non-obese Patients: Impact of Breast Size on Complications. Aesthetic Plast Surg 2016;40:71-8. [Crossref] [PubMed]
  33. Yuen JC, Yue CJ, Erickson SW, et al. Comparison between Freeze-dried and Ready-to-use AlloDerm in Alloplastic Breast Reconstruction. Plast Reconstr Surg Glob Open 2014;2:e119. [Crossref] [PubMed]
  34. Yuen JC, Coleman CA, Erickson SW. Obesity-related Risk Factors in Implant-based Breast Reconstruction Using AlloDerm. Plast Reconstr Surg Glob Open 2017;5:e1231. [Crossref] [PubMed]
  35. Hadad I, Liu AS, Guo L. A New Approach to Minimize Acellular Dermal Matrix Use in Prosthesis-based Breast Reconstruction. Plast Reconstr Surg Glob Open 2015;3:e472. [Crossref] [PubMed]
  36. Kachare MD, Kachare SD, Vivace BJ, et al. Restoring Breast Volume in High BMI Patients: A Single-Center Review of Breast Reconstruction Using Hyperinflated Saline Implants. Eplasty 2022;22:e30. [PubMed]
  37. Ota D, Fukuuchi A, Iwahira Y, et al. Identification of complications in mastectomy with immediate reconstruction using tissue expanders and permanent implants for breast cancer patients. Breast Cancer 2016;23:400-6. [Crossref] [PubMed]
  38. Rothe K, Münster N, Hapfelmeier A, et al. Does the Duration of Perioperative Antibiotic Prophylaxis Influence the Incidence of Postoperative Surgical-Site Infections in Implant-Based Breast Reconstruction in Women with Breast Cancer? A Retrospective Study. Plast Reconstr Surg 2022;149:617e-28e. [Crossref] [PubMed]
  39. Walker NJ, Park JG, Maus JC, et al. Prepectoral Versus Subpectoral Breast Reconstruction in High-Body Mass Index Patients. Ann Plast Surg 2021;87:136-43. [Crossref] [PubMed]
  40. Wink JD, Fischer JP, Nelson JA, et al. Direct-to-implant breast reconstruction: an analysis of 1612 cases from the ACS-NSQIP surgical outcomes database. J Plast Surg Hand Surg 2014;48:375-81. [Crossref] [PubMed]
  41. Checklists - STROBE. Accessed May 25, 2022. Available online: https://www.strobe-statement.org/checklists/
  42. Levels of evidence in research. Accessed October 10, 2023. Available online: https://scientific-publishing.webshop.elsevier.com/research-process/levels-of-evidence-in-research/
  43. Weichman KE, Clavin NW, Miller HC, et al. Does the use of biopatch devices at drain sites reduce perioperative infectious complications in patients undergoing immediate tissue expander breast reconstruction? Plast Reconstr Surg 2015;135:9e-17e. [Crossref] [PubMed]
  44. Srinivasa DR, Clemens MW, Qi J, et al. Obesity and Breast Reconstruction: Complications and Patient-Reported Outcomes in a Multicenter, Prospective Study. Plast Reconstr Surg 2020;145:481e-90e. [Crossref] [PubMed]
  45. Fischer JP, Nelson JA, Serletti JM, et al. Peri-operative risk factors associated with early tissue expander (TE) loss following immediate breast reconstruction (IBR): a review of 9305 patients from the 2005-2010 ACS-NSQIP datasets. J Plast Reconstr Aesthet Surg 2013;66:1504-12. [Crossref] [PubMed]
  46. Pannucci CJ, Antony AK, Wilkins EG. The impact of acellular dermal matrix on tissue expander/implant loss in breast reconstruction: an analysis of the tracking outcomes and operations in plastic surgery database. Plast Reconstr Surg 2013;132:1-10. [Crossref] [PubMed]
  47. Leitner HS, Pauzenberger R, Ederer IA, et al. BMI Specific Complications Following Implant-Based Breast Reconstruction after Mastectomy. J Clin Med 2021;10:5665. [Crossref] [PubMed]
doi: 10.21037/abs-23-73
Cite this article as: Odgaard EB, Frid NL, Lauritzen E, Damsgaard TE. The impact of body mass index on direct to implant and two-stage immediate breast reconstruction procedure: a systematic review. Ann Breast Surg 2024;8:34.

Article Options

Download Citation

Share