The Effect of Massive Weight Loss Status, Amount of Weight Loss, and Method of Weight Loss on Body Contouring Outcomes

Background: The impact of massive weight loss (MWL) on body contouring procedures and outcomes has not been firmly established in the literature.

Objective: The authors investigate the correlations between MWL status, the method of achieving MWL, and the amount of weight lost with wound-healing complications after body contouring procedures.

Methods: The charts of 450 patients (124 of whom had undergone MWL) who underwent body contouring procedures including abdominoplasty, brachioplasty, thighplasty, breast mastopexy/reduction, lower bodylift, bodylift, buttock lift, and liposuction were reviewed. MWL patients were classified as having achieved weight loss through diet and exercise, gastric banding or sleeving, or gastric bypass. Postoperative complication data were collected, including cases of infection, delayed wound healing, seroma, hematoma, dehiscence, and overall wound problems. Odds ratios (OR) were estimated using 4 multivariate logistic regression models.

Results: MWL status was a significant predictor of wound problems (OR, 2.69; P < .001). Patients with 50 to 100 lbs of weight loss did not have a significantly increased risk of wound problems (OR, 1.93; P = .085), while patients with over 100 lbs of weight loss did (OR, 3.98; P < .001). Gastric bypass (OR, 3.01; P = <.001) had a higher risk correlation than did diet and exercise (OR, 2.72, P = .023) or restrictive bariatric surgery (OR, 2.31; P = .038) as a weight loss method. Patients who lost over 100 lbs demonstrated increased risk of complications if they had gastric bypass or restrictive procedures.

Conclusions: MWL was a significant risk factor for wound complications in the body contouring population. Method and amount of weight loss were also significant factors in predicting complications.

The rising rate of obesity over the past few decades is among the most pervasive health trends; currently, more than one-third of Americans are considered obese.¹ Associated comorbidities such as diabetes mellitus, cardiovascular disease, hyperlipidemia, arterial hypertension, and depression have increased the need for bariatric surgery to achieve weight loss and diminish the concomitant comorbidities in this patient population effectively and safely.² Approximately 101 000 gastric bypass, gastric banding, and gastric sleeve procedures were performed in the United States in 2011, reflecting the prevalence of obesity within the population.³

Massive weight loss (MWL) following bariatric surgery often leads to skin excess; 68% to 85% of postbariatric surgery patients desire body contouring surgery to remove the excess,^4,5 which represents an area of steady growth within plastic surgery. Procedures such as abdominoplasty have increased over 360% in the last 16 years.⁶ Body contouring procedures are not without risk, as surgery time can be prolonged and relatively high complication rates have been cited in the literature.^7,8 MWL patients also carry unique risks because of redundant skin, nutritional deficiencies, and overall metabolic differences, especially as these factors relate to the wound-healing process.⁹

In this study, we sought not only to distinguish how outcomes were affected by MWL status among the entire body contouring patient population but also further analyze the risk of the various methods of achieving MWL.

Methods

Study Design

A UT Southwestern institutional review board–approved retrospective chart review was performed of 1801 complex plastic surgical cases performed at a single academic medical center between January 1, 2008, and January 31, 2012. Relevant information was abstracted from patient charts and hospital records, and a database was constructed to capture a broad range of procedures with long operative times, including some combined surgeries. Patients included in the analysis received abdominoplasty, brachioplasty, thighplasty, breast mastopexy/reduction, lower bodylift, bodylift, buttock lift, and/or liposuction. Patients who returned to the study site for additional body contouring procedures at multiple dates were selected only for their first encounter to reduce statistical bias. Body contouring procedures combined with hernia repair were excluded. Of the 1801 cases included in the database, 450 cases met the inclusion criteria. Of these 450 cases, 407 patients were women and 43 were men.

Preoperative patient characteristics, including sex, age, body mass index (BMI; kg/m²), MWL status, method of weight loss, and common comorbidities associated with postoperative complications were included in the analysis.^10,11 Patients were considered to have undergone MWL if they had achieved a weight loss of 50 lb or more. Method of weight loss was categorized as gastric bypass, restrictive (which included laparoscopic band and gastric sleeve procedures), and unspecified (which included patients lacking a specific history regarding their weight loss method). Postoperative complications were assessed and noted in clinical progress notes by attending physicians and included infection, delayed wound healing, seroma, hematoma, dehiscence, and overall wound problems, which is inclusive of all of the aforementioned complications. These complications were then abstracted from the chart review and included in the larger database.

Patient demographics were summarized as a mean and standard deviation for continuous variables and as a percentage for categorical variables. Univariate analyses were utilized to compare patient characteristics and comorbidities, and significant factors were selected for further analysis. Odds ratios were estimated using 4 multivariate logistic regression models: (1) a base model including MWL status, (2) a model adjusting for the amount of weight lost, (3) a model adjusting for the method used to achieve MWL, and (4) a model measuring the interaction between method of weight loss and the amount of weight lost. While history of myocardial infarction, coronary artery disease, chronic obstructive pulmonary disease, and deep venous thrombosis were included in the original models, they were eventually omitted from further statistical consideration. Statistical significance was assigned if P values were less than .05. All data analysis was conducted with Stata/SE Version 12.0 (StataCorp, Inc, College Station, Texas) statistical software.

Results

The average age of the study population was 45.4 years (range, 16–79 years). Overall patient demographics and complication rates are summarized in Table 1. The complication rate for the study population was 19.1% with an average follow-up time of 6 months. Of the 450 body contouring cases, 124 were classified as MWL patients, and univariate analyses comparing MWL patients with non-MWL patients are summarized in Table 2. The methods of achieving weight loss and corresponding wound problem rates are summarized in Table 3.

Multivariate logistic regression using the base model showed that MWL status was a statistically significant (odds ratio [OR], 2.69; P < .001) predictor of wound problems in body contouring patients (Table 4). A second logistic regression model (Table 5) estimating the effect of the amount of weight loss (50-100 lb and 100+ lb) demonstrated a statistically significant result for those in the 100+-lb category (OR, 3.98; P < .001) and, for the 50- to 100-lb group, a result that approached statistical significance (OR, 1.93, P = .085). A related model demonstrated an odds ratio of 1.0094 (P < .001) per each additional pound lost.

The method of weight loss was also analyzed in a multivariate logistic regression that regressed on each respective method: gastric bypass, restrictive (including gastric banding or gastric sleeve), and diet and exercise. All 3 methods demonstrated statistically significant differences regarding wound problems from the non-MWL population. Gastric bypass (OR, 3.01; P = .002) demonstrated a higher odds ratio than either diet and exercise (OR, 2.72; P = .023) or restrictive bariatric surgery (OR, 2.31; P = .038). These data are summarized in Table 6.

The interaction between the method of weight loss and the amount of weight loss was explored in the final multivariate logistic regression (Table 7). Although the regression estimates that the method of weight loss and a weight loss of 50 to 100 lb did not demonstrate a statistically significant risk, the interaction between 100 lb or more lost and the method of weight loss was statistically significant, except in the diet and exercise population.

Discussion

The connection between MWL and body contouring surgery has been the subject of an amalgam of original research as well as advisories regarding the evaluation and treatment of this patient population.^12–15 Our analysis indicated that MWL patients have a statistically significant increased risk of developing wound complications in the postoperative period compared with the non-MWL population. However, this conclusion has been debated in the body contouring literature; Vastine et al¹⁶ and Kerviler et al¹⁷ indicated that bariatric surgery did not correlate with an increased risk of complications in body contouring procedures, while Greco et al¹² and Staalsen et al¹⁸ published results to the contrary. Despite their differing conclusions, these studies all had a comparatively small sample size, and statistical power consequently may have been hampered.

Our analysis showed an almost 2-fold increased risk of complications conditional on the amount of weight lost in the MWL patient. This finding was corroborated by Coon et al,¹⁹ who found that maximum BMI and change in BMI were associated with developing wound complications, as change in BMI can be associated with the amount of weight lost. Our study would have benefited from similarly utilizing change in BMI as a variable for analysis; however, due to constraints in the data set, this metric was unavailable. Furthermore, our study was unable to compare complication rates among the various body contouring procedures due to a relatively small sample size that would have produced statistically unreliable results. While larger procedures like lower bodylift would ostensibly have higher complication rates than strictly liposuction, for example, the procedures analyzed all fall under the purview of “body contouring” as it is defined in the literature and textbooks and were thus studied as a whole.^20,21 Differences between these body contouring procedures, however, should be studied in the future.

The method of achieving MWL proved an indicator in predicting complication rates for body contouring surgery. Our data indicated that regardless of the method of MWL, these patients demonstrated increased risk for wound problems compared with the non-MWL patient. Gastric bypass patients, however, had a greater risk than either the restrictive bariatric surgery population or the diet and exercise population. The current literature is sparse regarding the correlation of restrictive bariatric surgeries and outcomes for body contouring surgeries but has focused on differences between weight loss achieved through dietetic means and gastric bypass.^16–18 Gusenoff et al²² noted that there was no significant difference in outcomes between patients treated with bariatric procedures and patients who dieted and exercised.

A trend relating the amount of weight lost and the method of weight loss emerged in our study, as MWL below 100 lb was not a significant risk factor, no matter the method. Weight loss greater than 100 lb indicated significant risk associated with both restrictive bariatric procedures and gastric bypass, but not diet and exercise. The diet and exercise group with more than 100 lb lost included only 4 patients; thus, a larger sample size within this population would more accurately estimate the odds ratio.

The cause of the MWL patients' increased risk of wound complication may be multifactorial since nutritional deficiencies, biomechanical changes within the skin, and biological and physiologic alterations may occur within this patient population.²³ Collagen and elastic fiber differences as well as tissue protein expression were found to be abnormal among a population of MWL patients receiving body contouring surgery.²⁴ Furthermore, an examination of wound regulatory proteins among cancer, burn, obese, and posttransplant populations has suggested that similar changes may occur in the MWL population.²⁵ Among the chief concerns for the postbariatric patient are nutritional deficiencies. Nutritional intake can remain inadequate as much as a year after surgery, and among gastric bypass patients, intake is often under 1000 kcal/d with significant protein deficiencies 1 year removed from surgery.^26,27 While there is a mixture of nutritional deficiencies that contribute to inadequate wound healing, addressing protein deficiencies has been targeted as a potential means of reducing these complications, especially as protein is necessary for fibroblast formation as well as collagen production and angiogenesis.^9,28 One study of body contouring procedures after MWL utilized protein supplementation and noted improved outcomes compared with a control group and overall complication rates similar to nonbariatric patients.²⁹ Surgeons at our study site currently utilize preoperative tests for prealbumin and daily protein supplementation on average of 30 to 40 g for 1 month prior to surgery for the MWL patient. Our results may indicate that dietary supplementation should be tailored specifically to the method of weight loss as well as the amount of weight lost.

Conclusions

Massive weight loss status is a significant factor in determining wound complications in the body contouring population. The amount of weight lost and the means through which this weight loss is achieved also demonstrate significant effects on predicting wound complications. Surgeons should be cognizant of these factors when discussing body contouring procedures with their patients and also prepare for surgery by utilizing protein supplementation.

Acknowledgments

The authors thank Roberto Cortez, Rachel Hein, Kendall Anigian, Travis Miller, James Jewell, Natalie Sciano, Bhavani Gannavarapu, Janeiro Okafor, and Alan Wang for their help compiling the original database. They also thank Krista Hardy and Jerzy Lysikowski for their feedback. Additionally, they thank Debby Noble and the research support team at UT Southwestern for their invaluable efforts.

Disclosures

Dr Davis receives research grants from Convatec (Skillman, New Jersey), Thermotek (Flower Mound, Texas), Unilever (London, England), Kensey Nash (Exton, PA), Andrew Technologies (Tustin, California), TA Sciences (New York, New York), and Innovative Therapies (Pompano Beach, Florida). She is a paid consultant for Thermotek and Innovative Therapies, Inc. Dr Kenkel is a paid investigator for Allergan (Irvine, California), Erchonia (McKinney, Texas), and Ultrashape (Irvine, California), and is on the Advisory Board of Kythera (Calabasas, CA). Mr Constantine has nothing to disclose.

Funding

The authors received no financial support for the research, authorship, and publication of this article.

References