A propensity score matched analysis of obesity as an independent risk factor for postoperative complications in reduction mammaplasty

Abstract

Aim: Reduction mammaplasty is a commonly performed procedure for the treatment of symptomatic macromastia and is increasingly desired by the obese population. With the increasing prevalence obesity in the population, it is imperative to understand its effect on postoperative outcomes. The purpose of this study is to evaluate obesity as an independent risk factor for postoperative complications in breast reduction surgery using 1:1 patient matching through propensity scores between obese patients and non-obese controls.

Methods: Between 2005 and 2013, the National Surgical Quality Improvement Program dataset identified a total of 6,016 patients as having undergone primary reduction mammaplasty with 30-day postoperative follow-up. Patients were divided into obese [body mass index (BMI) of 30 or more] vs. not obese (BMI below 30). Patients were initially analyzed using standard multivariable analysis. Using propensity scores obtained from a logistic regression model, patients were subsequently matched 1:1 according to preoperative and operative variables to truly isolate the effect of obesity on surgical outcomes. Outcomes were compared between the matched cohorts using McNemar’s test and the Wilcoxon signed rank test.

Results: In unmatched multivariable analysis, rates of overall complications (7.2% vs. 5.3%, P = 0.0024), wound complications (5.5% vs. 3.6%, P = 0.0004), superficial surgical site infection (4.1% vs. 2.8%, P = 0.0050), and wound dehiscence (0.3% vs. 1.1%, P = 0.0005) were found to be statistically different between obese vs. non-obese, respectively. However, when comparing 1:1 matched obese and non-obese patients, only wound complications (4.6% vs. 3.1%, P = 0.0334) were significantly increased in the obese cohort.

Conclusion: Using the most robust statistical tools available, obesity was determined to affect wound complications after breast reduction without increased detriment on other major complications when compared to the non-obese. Obesity should be a considered with other preoperative comorbidities, rather than an independent contraindication to surgery. Breast reduction appears to be safe in the obese patient who is otherwise healthy.

Keywords

Obesity / breast reduction / reduction mammoplasty / National Surgical Quality Improvement Program / propensity score

References

[1] American Society of Plastic Surgeons. 2014 Plastic Surgery Statistics Report. Available from: http://www.plasticsurgery.org/Documents/news-resources/statistics/2014-statistics/plastic-surgery-statsitics-full-report.pdf [Last Accessed on January 6, 2016].

[2] Coriddi M,Taghizadeh M.Analysis of satisfaction and well-being following breast reduction using a validated survey instrument: the BREAST-Q..Plast Reconstr Surg2013;132:285-90

[3] Blomqvist L.Three-year follow-up on clinical symptoms and health-related quality of life after reduction mammaplasty..Plast Reconstr Surg2004;114:49-54

[4] Carty MJ,Gu X,Orgill D.Patient satisfaction and surgeon experience: A follow-up to the reduction mammaplasty learning curve study..Eplasty2012;12:e22 PMCID:PMC3347872

[5] Davis GM,Short K,Bengtson BP.Reduction mammaplasty: long-term efficacy, morbidity, and patient satisfaction..Plast Reconstr Surg1995;96:1106-10

[6] Nelson JA,Chung CU,Tuggle CT,Kovach SJ.Obesity and early complications following reduction mammaplasty: an analysis of 4545 patients from the 2005-2011 NSQIP datasets..J Plast Surg Hand Surg2014;48:334-9

[7] Sieffert M,Abbott LE.Obesity is associated with increased health care charges in patients undergoing outpatient plastic surgery..Plast Reconstr Surg2015;135:1396-404

[8] Nguyen JT,Schnur PL,Winn SR.Reduction mammaplasty: a review of managed care medical policy coverage criteria..Plast Reconstr Surg2008;121:1092-100

[9] Zubowski R,Foray-Kaplon A,Lucas AR,Heil D.Relationship of obesity and specimen weight to complications in reduction mammaplasty..Plast Reconstr Surg2000;106:998-1003

[10] Blomqvist L.Reduction mammaplasty: analysis of patients' weight, resection weights, and late complications..Scand J Plast Reconstr Surg Hand Surg2006;30:207-10

[11] Gamboa-Bobadilla GM.Large-volume reduction mammaplasty: the effect of body mass index on postoperative complications..Ann Plast Surg2007;58:246-9

[12] Baldwin CJ,Batchelor AG.The variation in breast density and its relationship to delayed wound healing: a prospective study of 40 reduction mammoplasties..J Plast Reconstr Aesthet Surg2010;63:663-5

[13] Chun YS,Gu X,Carty MJ.Body mass index as a predictor of postoperative complications in reduction mammaplasty..Plast Reconstr Surg2012;129:e228-33

[14] Wagner DS.The influence of obesity and volume of resection on success in reduction mammaplasty: an outcomes study..Plast Reconstr Surg2005;115:1034-8

[15] Setala L,Joukainen S,Berg L,Härmä M.Obesity and complications in breast reduction surgery: are restrictions justified?.J Plast Reconstr Aesthet Surg2009;62:195-9

[16] Roehl K,Gomez V.Breast reduction: safe in the morbidly obese?.Plast Reconstr Surg2008;122:370-8

[17] Cunningham BL,Kerrigan CL.Analysis of breast reduction complications derived from the BRAVO study..Plast Reconstr Surg2005;115:1597-604

[18] Shiloach M,Steeger JE,Bartzokis K,Richards KE,Hall BL.Toward robust information: data quality and inter-rater reliability in the American College of Surgeons National Surgical Quality Improvement Program..J Am Coll Surg2010;210:6-16

[19] Ogden CL,Kit BK.Prevalence of childhood and adult obesity in the United States, 2011-2012..JAMA2014;311:806-14 PMCID:PMC4770258

[20] Wang Y.The obesity epidemic in the United States - gender, age, socioeconomic, racial/ethnic, and geographic characteristics: a systematic review and meta-regression analysis..Epidemiol Rev2007;29:6-28

[21] Flegal KM,Orpana H.Association of all-cause mortality with overweight and obesity using standard body mass index categories: a systematic review and meta-analysis..JAMA2013;309:71-82 PMCID:PMC4855514

[22] Cepeda MS,Farrar JT.Comparison of logistic regression versus propensity score when the number of events is low and there are multiple confounders..Am J Epidemiol2003;158:280-7

[23] Tadiparthi S.Use of patient body mass index as a rationing tool in breast reduction surgery..Plast Reconstr Surg2008;122:35-6

[24] Kitsios GD,Callahan S,Campagna AC.Can we trust observational studies using propensity scores in the critical care literature? A systematic comparison with randomized clinical trials..Crit Care Med2015;43:1870-9

[25] Wagner IJ,Allen RJJr,Canizares O,Warren SM.Obesity impairs wound closure through a vasculogenic mechanism..Wound Repair Regen2012;20:512-22

[26] Kim BS,Bernhagen J.The macrophage migration inhibitory factor protein superfamily in obesity and wound repair..Exp Mol Med2015;47:e161 PMCID:PMC4454997

[27] Fischer JP,Shang EK,Serletti JM.Complications following reduction mammaplasty: a review of 3538 Cases from the 2005-2010 NSQIP data sets..Aesthet Surg J2014;34:66-73