Quality of Life After Bariatric Surgery: Comparison of Four Different Surgical Procedures

Abstract

Objective:

To identify predictors that may affect postoperative quality of life (QOL) after bariatric surgery.

Methods:

German speaking patients who underwent bariatric surgery between 2003 and 2010 were included. Out of the total of 132 patients fulfilling the inclusion criteria, 113 could be reached via phone interview (85.6%). Sixty-five patients underwent laparoscopic Roux-en-Y gastric bypass (LRYGB), 26 laparoscopic sleeve gastrectomy (LSG), 15 patients biliopancreatic diversion with duodenal switch (BPD/DS), and 7 patients laparoscopic gastric banding (LAGB). The German version of the bariatric QOL index questionnaire was used.

Results:

The study participants achieved a mean score of 51.2 ± 10.2 points, which is in normal range of healthy individuals. Patients operated at younger age had a better QOL than elderly patients. Men and women showed comparable postoperative QOL. Patients who had been already working before surgery or started to work postoperatively achieved more QOL score points than those who did not. LRYGB, LSG, LAGB, and BPD/DS all equally resulted in a good QOL after surgery (51 ± 11.3, 51.9 ± 7.1, 45.3 ± 9.6, 54 ± 9.7, p = 0.2).

Conclusion:

LRYGB, LSG, LAGB, and BPD/DS do not differ in terms of QOL 3.3 years after surgery. Young age and pre- and postoperative integration into work are positive predictors for good QOL after surgery. Postoperative QOL is significantly correlated to magnitude of weight loss after surgery (both percentage of total weight loss and percentage of excess weight loss).

Introduction

The increasing prevalence of obesity represents a major health problem across the globe. Obese patients are at an increased risk of comorbidities such as diabetes, hypertension, impaired physical activity, and depression with subsequently reduced quality of life (QOL).¹ Bariatric surgery has evolved as an effective and safe therapeutic option for treating morbid obesity. It can achieve sustained weight loss, remission of comorbidities, and leads to an improved QOL.^1–4 Contrary to the objective measures available for weight loss and comorbidities, QOL assessment after surgery remains controversial because it often relies on the judgement of the patient him/herself. At the present time, several validated questionnaires are available to assess QOL in obese persons before and after surgery.^5–7

The factors that determine QOL after surgery are not well understood. Strain et al. linked the degree of changes in QOL to the magnitude of postoperative weight loss with the peak improvement occurring 1–3 years after surgery.⁸ The SOS intervention study concluded that long-term weight reduction following bariatric surgery has a positive impact on health-related QOL for a period of up to 10 years after the operation.⁹ On the other hand, Muller et al. found no difference in the QOL index between patients after gastric bypass and gastric banding 3 years after surgery despite significantly different postoperative percentage of excess weight loss (%EWL).¹⁰ Several comparative studies linked improved QOL not only to %EWL but also to the improvement of obesity related comorbidities after surgery.^11,12

Since it is not conclusively clarified whether different surgical procedures lead to the same QOL, we conducted this study. Several patient and procedure related factors (age, gender, sexual and physical activity, integration into work, type of the surgical procedure, and time elapsed after surgery) were analyzed to determine significant predictors of QOL in patients undergoing bariatric surgery.

Methods

One hundred thirty-two patients who were operated in our hospital between 2003 and 2010 were included in this follow-up study. This is the full number of German-speaking patients getting a bariatric procedure during this period.

Since 2003, bariatric surgery only began to develop in Germany, only a few patients were operated and included in the first years. The number of bariatric patients increased to 60 patients per year in 2009/2010, however, 40% of the patients were not German-speaking. To ensure a good understanding of the questionnaire and avoid variability in the answers due to language difficulties we excluded patients who did not speak German. Another reason to exclude these patients was the frequent change of residence in this cohort.

Eighteen months was defined as the minimal time interval after the operation to avoid the large changes in body weight usually taking place during the first year after surgery to significantly affect QOL.

Out of the total of 132 patients fulfilling the inclusion criteria, 113 could be reached by phone and consented to participate in this open, single-center, prospective study. Approval from the local Institutional Review Board (IRB) and informed consent of all individuals were obtained.

All patients preoperatively fulfilled the inclusion criteria of the German guidelines for bariatric surgery and were operated laparoscopically using a standard technique. Sixty-five patients underwent laparoscopic Roux-en-Y gastric bypass (LRYGB), 26 laparoscopic sleeve gastrectomy (LSG), 15 patients biliopancreatic diversion with duodenal switch (BPD/DS), and 7 patients laparoscopic adjustable gastric banding (LAGB). The operative procedure was selected by the patient, with gastric bypass being our primary recommendation and gastric sleeve we advised for patients with a body mass index (BMI) over 60 kg/m².

Postoperative follow-up was offered to all patients after 2 weeks, 6 weeks, 18 weeks, 6 months, 9 months, 12 months, 18 months, and after 2 years. After this period, annual follow-up care was offered. On each visit, body weight and body composition was assessed by bioelectrical impedance analysis. Additionally, all patients received individualized nutritional counseling at every visit from a nutritionist specialized in bariatric surgery.

No major complications with impact on QOL 18 months after the operation occur.

During the phone interview, patients were asked to answer a range of questions. The German version of the bariatric QOL index questionnaire was used as it is validated.¹³ It evaluates the patient's subjective impression of his/her QOL, both in terms of psychological well-being, and social and physical functionality.

The questionnaire consists of 13 questions. Each answer is assessed by a point scale from 1 to 5 that are in the end summed up giving a maximal value of 65 points and a minimal of 13 points. The creators of the bariatric QOL index questionnaire assigned 50–55 points to be the normal range for healthy nonobese individuals and a score of more than 52 points representing a very good QOL. In our attempt to identify additional pre- and postoperative patient factors that would predict postoperative QOL, we added and analyzed patient factors including pre- and postoperative integration into work, along with physical and sexual activity. The type of bariatric procedure was also investigated in regard to affecting QOL later.

Statistical analysis

Quantitative Variables are presented by mean values ± standard deviation. For qualitative factors, absolute and relative frequencies are given.

To compare two mean values, two sample t-tests were done (for data approximately normally distributed); for skewed data the Mann–Whitney U test was used. For the comparison of three groups one-way ANOVAS and Kurskal–Wallis tests were done. To test the association between two qualitative factors χ² test or Fisher's exact test were applied, as appropriate. The association between two quantitative variables was assessed by Pearson's correlation coefficient.

Furthermore covariance analyses and multiple regression analyses were performed to simultaneously investigate the influence of several variables on a quantitative outcome. All statistical calculations were done with SAS, release 9.3 (SAS institute, Inc., Cary, NC). A test result was considered as statistically significant for p < 0.05.

Results

One hundred thirteen patients were reachable by phone and agreed to answer the questions and participate in our study. One hundred thirteen (85.6%) of all patients initially fulfilling the inclusion criteria could be reached by phone and consented to participate in the study. The study participants achieved a mean QOL score of 51.2 ± 10.2 points (minimum was 19 points and maximum was 65 points). This score is in the normal range of healthy nonobese volunteers (50–55 points).¹³

Time interval between the operation and questionnaire

The mean time interval between the operation and receiving our phone call was 3 ± 1.5 years (mean 3.29 years). The minimum time was intentionally restricted to a minimum of 1.5 years. The maximum time elapsed since the operation was 9.7 years (116.96 months). There was no significant correlation between the time interval after operation and QOL (p = 0.27).

Age

On the basis of their age at the time of surgery, patients were subdivided into two groups; above and below 50 years. QOL scores were compared between both categories. Patients who were younger than 50 years at the time of surgery had a higher score than those who were older (53.1 ± 8.9 vs. 47.2 ± 11.7, p = 0.009) (Table 1).

Table 1.

Parameters of Quality of Life

Parameter	Mean QOL score points
Age at time of operation
<50 years old	53.1 ± 8.9
< 50 years old	47.2 ± 11.7 (p = 0.009)^*
Sex
Male, n = 74 (65.5%)	51.1 ± 10.2
Female, n = 39 (34.5%)	51.3 ± 10.3 (p = 0.85)
Integration into work before operation
Yes (71.6%)	53.9 ± 8.3
No (28.4%)	49.0 ± 10.6 (p = 0.03)^*
After operation
Yes (80.4%)	53.9 ± 8.9
No (19.6%)	48.2 ± 10.0 (p = 0.02)^*
Sexual activity
Improved (61.4%)	52.4 ± 9.4
Not improved (38.6%)	50.2 ± 10.3 (p = 0.3)
Physical activity
Improved (73.5%)	52.3 ± 10.0
Not improved (26.5%)	48.4 ± 10.6 (p = 0.06)
Weight at time of interview
<35 kg/m²	54.4 ± 9.4
>35 kg/m²	46.9 ± 9.8 (p < 0.001)^*

The p-value less than 0.05 signed to a significant statistical difference.

QOL, quality of life.

Gender

Male (51.1) and female (51.3) patients had comparable QOL scores (p = 0.85).

Integration into work

According to their employment status before surgery, patients were classified into two groups, employed (71.6%) and unemployed (28.4%). Eighteen patients, who were either retired or students (still visiting a school), were excluded from evaluation of the employment status. After bariatric surgery, a higher rate of employment was registered (80.4%). Patients who were working before surgery had more QOL score points (53.9 ± 8.3) than those who did not (49.0 ± 10.6, p = 0.03). Employed patients who resumed work or succeeded in finding a new job after surgery had a better QOL than patients who remained jobless (53.9 ± 8.9 vs. 48.2 ± 10.0, p = 0.02).

Sexual activity

Patients were asked about changes in their sexual life after bariatric surgery. About 61.4% of our patients stated an improvement. However, patients who experienced a better sexual life following surgery did not have a significant difference in terms of QOL from those who answered negatively to such a change (52.4 ± 9.4 vs. 50.2 ± 10.3, p-value = 0.3).

Physical activity

With respect to physical activity after surgery, 73.5% of the patients felt more mobile and did sports on a regular basis versus 26.5% denying an improvement in this respect. Comparing the QOL in both groups, patients with improved physical activity achieved a better score (52.3 ± 10) than those without improvement (48.4 ± 10.6). This difference just failed in statistical significance (p = 0.06).

Patient's weight

Patients mean BMI at time of interview was 34.0 ± 6.7 kg/m² (99.3 ± 21.8 kg). Unsurprisingly QOL scores were strongly correlated to patients' weight at time of interview (p < 0.001). Mean QOL score for patients with BMI less than 35 kg/m² was 54.4 ± 9.4 versus 46.9 ± 9.8 in patients whose BMI were equal to or more than 35 kg/m² (p < 0.001).

Type of procedure

The participants of the study underwent commonly performed bariatric procedures; namely RYGB, gastric banding, sleeve gastrectomy, and BPD with duodenal switch. During the study period sleeve gastrectomy was still predominantly seen as a bridging procedure in super obese patients. The different procedures were compared in terms of weight loss and improved QOL after surgery.

We used both %EWL and percentage of total weight loss (%TWL) to comparatively evaluate the outcomes of different procedures. Both measurement tools significantly depended on the type of procedure. Patients who underwent BPD with duodenal switch (either as one or two step procedure) achieved more %EWL and %TWL than others (65.9% ± 29.0%, 40.8% ± 16% respectively). Patients with gastric band were able to lose only 29.4% of their excess weight. No significant difference between gastric bypass and sleeve gastrectomy patients in terms of weight loss was found (%EWL 57.8 ± 20.6, 56.3 ± 17.5 respectively, p = 0.8). The same conclusion is also valid for both operations in terms of %TWL (29.3 ± 10.4 for gastric bypass, 33.4 ± 11.3 for sleeve gastrectomy) (Table 2).

Table 2.

Comparison Between Different Bariatric Procedures

Parameter	LRYGB	LSG	LAGB	BPD/DS	All patients
Number	65	26	7	15	113
Preoperative weight (kg)	134.4 ± 18.6	162.8 ± 30.2	142.1 ± 15.7	163.9 ± 28.8	145.33 ± 26.5
Preoperative BMI (kg/m²)	46.3 ± 4.9	56.1 ± 8.4	46.3 ± 6.0	56.1 ± 8.0	49.8 ± 7.9
Weight at time of interview (kg)	95.0 ± 20.2	107.0 ± 21.3	119.4 ± 24.7	95.2 ± 22	99.3 ± 21
BMI at time of interview (kg/m²)	32.7 ± 5.9	37.0 ± 7.1	38.8 ± 8.4	32.4 ± 6.2	49.8 ± 7.9
%TWL at time of interview	29.3 ± 10.4	33.4 ± 11.3	15.6 ± 18.1	40.8 ± 16.0	31.0 ± 13.0
%EWL at time of interview	57.8 ± 20.6	56.3 ± 17.5	29.4 ± 35.8	65.9 ± 29.0	56.8 ± 23.3
Bariatric QOL index score (mean points)	51 ± 11.3	51.9 ± 7.1	45.3 ± 9.6	54 ± 9.7	51.2 ± 10.2

LRYGB, laparoscopic Roux-en-Y gastric bypass; LSG, laparoscopic sleeve gastrectomy; LAGB, laparoscopic gastric banding; BPD/DS, biliopancreatic diversion with duodenal switch; BMI, body mass index; %TWL, percentage of total weight loss; %EWL, percentage of excess weight loss.

Regarding QOL after surgery, patients who underwent BPD with switch had the highest score (mean 54 ± 9.7 points) while patients with gastric banding scored the least (mean 45.3 ± 9.6 points). However, none of the four procedures showed a statistically significant superiority in terms of QOL (p = 0.2).

There was a significant correlation between QOL and the magnitude of postoperative weight loss (measured in both %EWL and %TWL).

Discussion

The goal of this study was to identify predictors of QOL after bariatric surgery. The impact of patients' age, sex, integration into work, and improved physical and sexual activity was investigated. Furthermore, the effect of the type of operation, time interval elapsed after surgery, and magnitude of postoperative %EWL was analyzed in regard to QOL.

Patients after bariatric surgery experience significant short- and long-term improvement in their QOL.^14,15 Our results confirm these findings. Post-bariatric patients were able to achieve scores comparable to healthy nonobese individuals who answered the same questionnaire (50–55 points).

However, QOL improvements may not remain stable over time. Charalampakis et al. reported a decline in QOL scores measured by the Moorehead-Ardelt II questionnaire (MAII) in men 2 years after the operation while women continued to have a stable QOL. He attributed this phenomenon to the sustained subjective improvement in body image after surgery, which supposedly affects women more than men.¹⁶ In our study a significant difference in QOL between both genders was not observed.

Stress resulting from job loss or inability to find work is a leading cause of depression among obese patients.¹⁷ Sixteen percent of the initially unemployed patients succeeded in finding a job within 5 years of follow-up after surgery.¹⁸ In the current study we observed a significant positive influence of patient's employment status on their QOL. Patients who succeeded in finding a job before and/or after surgery had a better QOL than unemployed patients.

Several studies have reported improvements in sexual satisfaction, libido and erectile dysfunction after bariatric surgery.¹⁹ However, data is conflicting, as other studies indicate reduced sexual activity in some cases due to post-operative negative bodily attitudes (excess/hanging skin), weight re-gain 1 year after surgery and pre-surgery marital problems that persisted after the procedure.^20,21

Although most of our patients confirmed an improvement in sexual function after surgery (61.4%), we did not find a significant positive impact on the corresponding QOL. Patients reporting a better sexual life after their operation scored nearly the same QOL points as those who did not (52.4 ± 9.4 vs. 50.2 ± 10.3, p = 0.3).

Physical activity is an important contributor to the long-term maintenance of weight loss.²² Patients, who increased their physical activity after bariatric surgery, were able to achieve a better long-term surgical outcome.²³ In a sample of patients evaluated 3 months after a gastric bypass, Josbeno et al. reported significant improvements in physical function, less pain, and a trend toward increased physical activity.²⁴ The patients of our study reported an increase in their activity in a large percentage. These patients achieved an average of 4 QOL points more than the comparison group, but the results were not significantly different.

Weight loss after bariatric surgery could be reported in many different ways %TWL, %EWL, and excess body mass index loss (%EBMIL). Ivan de Laar suggested the use of %TWL as the best assessment tool for bariatric outcomes and goals.²⁵ Sczepaniak et al. compared outcomes after sleeve gastrectomy and gastric bypass using different measurement tools as %TWL, %EWL, and %EBMIL. He also recommended use of %TWL as an easy and accurate method for the expression of weight loss after surgery that is the least influenced by initial weight.^26,27

Therefore, both %EWL and %TWL were implemented in this study to comparatively evaluate the outcomes of surgery and its relation to improvement of QOL after surgery.

It is controversial whether the magnitude of weight loss is the most important predictor for changes in QOL after bariatric surgery. Several studies in the literature have demonstrated a significant improvement in physical and psychosocial QOL in line with weight loss,^11,12 but others merely found a weak predictive value for %EWL.¹⁴

Results of this study emphasized a clear significant correlation between %EWL or %TWL and improvement in QOL. Patients who were able to lose more weight after surgery had a better QOL than other patients who lost lesser weight.

Several studies discuss the influence of the patient's age on the outcome of bariatric surgery. Limbach et al. found age to be a significant negative predictor for %EWL.²⁸ Scozzari et al. concluded that bariatric surgery is less effective in older patients than younger ones. This was due to a significantly lower BMI decrease and a higher incidence of complications and mortality in the elderly group.²⁹ Our results support these findings in regard to QOL. We also found a strong correlation between QOL scores and the patient's age at the time of surgery. Patients younger than 50 years had a significantly higher chance to experience a better QOL after the operation than older patients.

This study compares QOL changes after the four commonly implemented bariatric procedures. In his recently published systematic review, Hachem et al. recognized only two studies that compared two different bariatric procedures in terms of improvement in QOL.³⁰

In one study, LSG resulted in significantly better improvements in psychosocial impact of QOL compared to LAGB.³¹

The second study was a randomized control trial comparing vertical banding gastroplasty and gastric bypass. There was a statistically significant improvement in gastrointestinal symptoms, physical, emotional, and social QOL domains in both groups. Improvements were more evident in the gastric bypass group.³²

However, Hachem et al. did not find any statistically significant differences in QOL between groups in studies that compared variations of the same type of surgery (e.g., laparoscopic gastric bypass vs. open gastric bypass).³⁰

BPD/DS has been proven to be successful in achieving and maintaining significant weight loss in the super obese population (BMI >50 kg/m²). Buchwald's systematic review, which included a total of 1565 patients, compared bariatric surgical procedures. He concluded that BPD/DS is the most effective operation with a percentage of excess body weight loss at 2 years follow-up of 73% followed by gastric bypass (63%), gastroplasty (56%), and gastric banding (49%).³³ Still, the proportion of BPD/DS procedures in relation to all bariatric surgeries declined from 6.1% to 4.9% to 2.1% in 2003, 2008, and 2011, respectively. This drop is generally attributed to the technical complexity of this procedure with longer hospital stay, higher perioperative morbidity and mortality rates in comparison to other procedures.³⁴ One-year complication rates as reported in the US Bariatric Outcomes Longitudinal Database after LAGB, LSG, RYGB, and BPD/DS were 4.6%, 10.8%, 14.9%, and 25.7%, respectively.³⁵ A common long-term complication after BPD/DS is protein malnutrition. Hamoui et al. followed 701 BPD/DS cases performed over a 10-year period and reported that 5% of patients developed complications necessitating revisional surgery. In the latter revisional surgery a postoperative complication rate of 15% was then seen.³⁶ Despite these possible adverse effects of BPD/DS that may potentially affect QOL, we could not find a significant difference between QOL values in BPD/DS and the other patients who had undergone other procedures. In summary, the type of the bariatric procedure did not influence the QOL in our study. Although patients underwent different operations (sleeve gastrectomy, gastric Banding, RYGB and BPD with duodenal switch), no significant differences in terms of postoperative QOL were found.

These results are in accordance with the early results of the Swiss Multicentre Bypass or Sleeve Study that found no difference in QOL between sleeve gastrectomy and gastric bypass 1 year after the operation.¹⁵ Other published studies have shown similar results up to 5 years after surgery.³⁷

In our analysis BPD patients demonstrated the best QOL and satisfaction after surgery. A potential explanation is that, in addition to a preoperative small sample size (n = 15), these patients were starting from a low QOL because of their relatively higher BMI than other patients (mean BMI 55.1). Moreover, the questionnaire we used, as all others, assesses diarrhea—a major complaint after BPD—only as a yes or no symptom ignoring the number of daily motions, which markedly varies among patients groups after surgery.

The observation that patients after BPD experience the best QOL after surgery is backed up by data published by Duarte et al. showing better results for BPD than banded RYGB in terms of “general state of health” and “pain,” according to responses to the SF-36 tool, and in terms of “sexual interest,” according to responses to the M-A QoLQ II tool.³⁸

Limitations of the study

The major limitations of this study are the small sample size and the lack of baseline QOL scores before surgery. Consequently, we were not able to detect or evaluate changes or improvements after the operation in comparison to before surgery.

Conclusion

Ethical Approval

Approval from the local IRB was obtained and is in agreement with the Helsinki declaration.

Statement of Informed Consent

Informed consent was obtained from all individual participants included in the study.

Footnotes

Author Disclosure Statement

The authors declare that they have no competing interests.

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