Long-Term Results after Bariatric Surgery: A Patient-Centered Analysis

Abstract

Background:

Long-term bariatric surgery studies are scarce. We report a 5- and 10-year follow-up after bariatric surgery with a focus on patient-centered outcomes.

Methods:

At the Maastricht University Medical Centre 150 participants completed mailed surveys in 2005 and 2010.

Results:

In 2005, average weight decreased from 134.5 to 96.2 kg, representing a mean weight loss of 28.5%. Body mass index (BMI) decreased 13.3 kg/m², from 46.5 to 33.2, but patient-to-patient variability was high. In 2010, mean weight and BMI were unchanged when compared with 2005. Reoperation rates were 14% and 27% in 2005 and 2010, respectively, and were negatively associated with satisfaction (trend). In 2010, 40% were satisfied with their current weight, while 74% of the participants would, given current knowledge and experience, again opt for bariatric surgery 10 years earlier.

Conclusions:

Most subjects would reconsider a bariatric trajectory, although more than half were unsatisfied with their current weight. For patients, success of bariatric surgery seems more than weight loss. The results need to be replicated. If we can clarify the factors of (dis-)satisfaction from the patients' perspective, we can better understand how to set expectations and prevent a mismatch between patient and provider.

Introduction

Bariatric surgery rates increase worldwide.¹ However, long-term studies remain scarce. Studies reported loss of 30% to 40% of initial weight, 40% to 75% of excess body weight, a reduction in mortality, and improvement of metabolic disorders and cardiovascular risk² with acceptable costs and increased quality of life.³ However, others reported unsuccessful weight loss or even weight regain in a substantial subgroup,^4–6 dissatisfaction with weight loss, possible side effects and complications, and high patient-to-patient variability.^3,4,7–9 The role of psychological and dietary factors needs more exploration.⁴

Bariatric study outcomes usually include mean weight loss, body mass index (BMI), percentage of Excess Weight Loss (EWL), Quality of Life, and comorbidities.¹⁰ However, definitions of successful weight loss are diverse, including loss of at least 25% preoperative weight, loss to within 50% of ideal body weight,¹¹ EWL of 50% or more,¹¹ and sustained EWL of 50% for at least 5 years.¹² Moreover, the methods used to calculate EWL were diverse; in papers published in MEDLINE-listed journals, five different methods to obtain EWL were used.^13,14 Therefore, EWL is not included in the present study.

The outcome “quality of life” has also been criticized because both definition and operationalization lack consistency.^7,15 Few studies include the patient's perspective. Elucidating patients' perspectives will help inform surgical selection procedures and improve postoperative care.¹⁵ The present article reports long-term results from the perspective of both technical (weight, BMI) and subjective outcomes (satisfaction with current weight and opinion on the total bariatric trajectory).

Materials and Methods

Approval for the study was granted by the Medical Ethics Committee of Maastricht University Medical Centre (MUMC). The study is in accordance with the provisions in the current version of the Declaration of Helsinki.

Participants

At the MUMC, all patients opting for bariatric surgery are referred by the department of surgery for psychological screening. In 2005, a list, including 490 names of patients referred for screening between 1996 and 2002, was available. Individuals on this list were contacted by phone and were invited to participate, until a predefined number of 150 participants agreed to participate. As the names were selected consecutively stratified by year, this selection was expected to result in a representative subgroup. Most names were from the 2000 and 2001 list. Inclusion criterion was bariatric surgery performed at least 2 years before the inclusion date. Some persons could not be traced (n = 45), did not agree to participate (n = 4), had no bariatric surgery after screening (n = 7), or died (n = 1). Therefore, researchers selected patients consecutively from a list and only 49 were eligible, but did not participate in the study.

Procedure

By ordinary mail, participants received an informed consent form as well as a written survey, including among others the topics weight, eating, perceived mental health, perceived physical health, and overall satisfaction. The questions used are available upon request.

Weight stability was defined in the survey as weight fluctuation of three kilograms maximum. The patients' overall satisfaction with the total bariatric trajectory was assessed using the question “if you knew then what you know now, would you have chosen to undergo bariatric surgery?” A similar question “would you again choose the same type of operation” was also included. Participants could give reasons why they were unsatisfied (open-ended question).

After informed consent, preoperative weight, BMI, and postoperative weight at 24 months were obtained from the medical files. In 2010, the cohort of 2005 responders received a small adjusted version of the 2005 survey.

Statistical analyses

All analyses were performed using STATA, version 11.2.¹⁶ Pearson Chi-square or t-tests were used to compare responders with nonresponders. A logistic regression analysis was performed to analyze the association between reoperation and satisfaction with the bariatric trajectory. In addition, reasons why participants were unsatisfied with the bariatric trajectory were explored.

Results

In 2005, 101 participants responded (67%), 82 were women (82%; Table 1). Women were aged 43.5 years, men 48.9 years. Average time since first surgery was 4.6 years (median 4.0, range 1–9 years). Six responders had postponed their operation and, therefore, had a postoperative period of 1–1.5 years. Fifty percent had primary education, 37% secondary, and 13% high education. Average initial weight and BMI were 134.5 kg (median 130, range 85.6–205.0) and 46.5 kg/m² (median 45, range 33.9–69.4), respectively. Laparoscopic Adjustable Gastric Banding (LAGB) was performed more frequently (Table 1).

Table 1.

Demographic Data, Type, and Frequency of Bariatric Procedures

	Preoperative	2005	2010
N	97	101	46
Female, n (%)	79 (81%)	82 (81%)	38 (83%)
Mean age by sex (median, range), years
Female	37.0 (37, 18–59)	43.5 (43, 23–65)	48.8 (49, 29–68)
Male	44.3 (43, 29–60)^a	48.9 (51, 32–62)	53.5 (54, 45–63)
Mean total	38.3 (37, 18–60)	44.5 (44, 23–65)	49.6 (49, 29–68)
Education
Primary	50 (50%)	50 (50%)	17 (40.5%)
Secondary	37 (37%)	37 (37%)	19 (45.2%)

Type	First, n (%)	Second, n (%)	First, n (%)	Second, n (%)
n	99	14	40	10
LAGB	54 (55)	2 (15)	21 (53)	2 (20)
VGB	39 (39)	0 (0)	17 (42)	0 (0)
RYGB	6 (6)	12 (85)	2 (5)	8 (80)

Frequency of surgery	n = 100 (%)	n = 44 (%)
One surgery	86 (86)	31 (71)
Two surgeries	14 (14)	12 (27)
Three surgeries	0 (0)	1 (2)^b

Preoperative phase: age male significant older than female: p < 0.001; t = 2.90; df = 95.

One person required but cancelled a third operation.

LAGB, laparoscopic adjustable gastric banding; RYGB, roux-en-Y gastric bypass; VGB, vertical banded gastroplasty.

In 2010, 46 participants responded (46%), 38 were women (83%). Average length of time after the first surgery was 9.3 years (median 8.6, range 6–14 years).

In 2005, nonresponders and responders did not differ in gender (86% and 82% women, chi-square = 0.53, p = 0.5, df = 1), preoperative mean age (36.9 and 38.3 years; t = 0.8; df = 130; p = 0.44), preoperative weight (129.4 and 134.5 kg, t = 1.1; df = 133; p = 0.27), and initial BMI (45.8 and 46.5 kg/m², t = 0.5; df = 133; p = 0.62). In 2010, nonresponders and responders also did not differ (gender 80% and 83%, chi-square = 0.11, p = 0.7, df = 1; preoperative mean age: 45.3 and 49.6 years, t = 0.9; df = 98; p = 0.38; preoperative mean weight: 137.3 and 131.1 kg, t = 1.3; df = 98; p = 0.20; and mean initial BMI 47.1 and 45.8 kg/m², t = 1.0; df = 98; p = 0.33).

Weight loss, weight stability, and satisfaction

Two years postoperatively, mean weight was 93.4 kg (median 90, range 57–165). Mean weight loss was 40.6 kg (median 40.0, range 13.6–115). Mean BMI was 31.9 kg/m² (median 30.6, range 20.3–47.7 kg/m²), and mean BMI reduction was 14.0 points. In 2005, mean weight was 96.2 kg and mean weight loss was 38.1 kg (median 38.0). Patient-to-patient variability was high, ranging between 10 kg above initial weight and 92 kg weight loss. Mean BMI was 33.2 kg/m² (median 31.2, range 20.5–60.2 kg/m²), and mean BMI reduction was 13.3 points. In 2010, mean weight and BMI were similar to the 2005 figures (96.4 kg, median 93.0, range 60–145; 33.7 kg/m², median 32.7, range 23.9–48.4, respectively). Furthermore, average weight loss was 34.6 kg and varied between 3.4 kg above initial weight and 69 kg weight loss. Mean BMI reduction was 12.2 points.

Table 2 presents initial mean weight and mean weight loss after 2 years, at the 2005 and the 2010 assessment. In 2005, 42% of the total group reported weight stability. In 2010, 56% of the total group reported weight stability, of which 83% reported weight stability for more than 2 years. Self-reported reasons for weight fluctuation were, for example, eating habits, use of medication (prednisone, antidepressants), pregnancy, complications of surgery, still losing weight, stress, and emotional eating.

Table 2.

Initial Mean Weight and Mean Weight Loss After 2 Years, at the 2005 and the 2010 Assessment

Group	Total, kg (n)	LABG, kg (n)	VBG, kg (n)
Initial mean weight	134.5 (101)	135.5 (50)	130.2 (37)
Two-year follow-up	40.6 (53)	37.7 (30)	40.7 (20)
2005 assessment	38.1 (99)	34.7 (50)^a	39.8 (36)^a
2010 assessment	34.6 (45)	33.7 (24)^a	31.2 (17)^a

Without revision surgery.

In 2010, 40% of the responders (n = 18) were satisfied with their current weight. The “unsatisfied” group opted for extra weight loss, varying between 5 and 60 kg. Reported reasons for insufficient weight loss were difficulties changing eating habits (irregularity, caloric food, emotional and stress eating, vomiting), physical problems (lungs, thyroid, and hormonal problems), medication (prednisone, antidepressants), and pregnancy.

Reoperations

In 2005, 14% had a reoperation in 2010, this was 27%. One participant (2%) underwent three operations (Table 1).

Satisfaction bariatric trajectory

In 2005, 82% (n = 81) indicated to be satisfied with the bariatric trajectory. In 2010, this was 74% (n = 34) (Table 3). Reasons to opt for a bariatric trajectory again were the amount of weight loss, life changes that improved the Quality of Life, and postoperative support for adequate weight management. Reasons not to opt for a bariatric trajectory again were as follows: disappointment in weight changes (less than expected, weight regain), still having eating problems (intolerance of specific foods, unintentional vomiting, reflux, and swallowing complaints), complications, and other physical problems.

Table 3.

Frequencies of “Yes” or “No” to the Question “If You Knew Then What You Know Now, Would You Have Chosen to Undergo Bariatric Surgery?”

	2005 ^a		2010
	Yes, % (n)	No, % (n)	Yes, % (n)	No, % (n)
Total group	82 (81)	18 (18)	74 (34)	26 (12)
LABG	90 (45)	10 (5)	—	—
VGB	74 (26)	26 (9)	—	—
RYGB	—	—	—	—
RYGB after VGB	—	—	—	—

Pearson χ²(3) = 8.3690, Pr = 0.039.

—, numbers were too small to present.

Participants with a reoperation were less satisfied than participants who had had one surgery, but this association was statistically imprecise by conventional alpha (2005 odds ratio = 0.46, p = 0.2; 2010 odds ratio = 0.32, p = 0.1).

Would the participant choose the same type of surgery again?

In 2005, 68% of all participants would choose the same type of surgery. In the LAGB group, this was 67%, and in the vertical banded gastroplasty (VBG) group, this was 38%. In 2010, 59% of the participants would choose the same type of surgery. Within the LAGB group, 70% again would choose LAGB, while within the VBG group, this was 44%.

Discussion

Weight and patient-to-patient variability

At the 2005 assessment, preoperative weight decreased with 28%, corresponding with 38 kg weight loss. On average, initial BMI dropped 13.3 kg/m². In 2010, the results were similar. Previous 5-year follow-up studies showed weight loss between 35 and 52 kg and BMI reduction between 14 and 17 points.⁷

Previous 9- to 11-year follow-up studies reported a broad range of weight loss between 20 and 30 kg¹⁰ and BMI reduction of 10–14 points.^8,9,17 For example, 16% loss of initial body weight was reported, at 10-year follow-up, in the SOS study.¹⁸ A recent study, at 11 years follow-up, mentioned a percentage total weight loss of 40.7% (sd: 10.8%) with the greatest weight loss in the super obese category (BMI >50 kg/m).¹⁹ In addition, a 14-year follow-up study reported a 30% weight reduction, on average.²⁰ In the present study, the number of patients was too small to stratify by type of surgery. The main types of surgery were LAGB and VGB. Although in the Netherlands in 2011, roux-en-Ygastric bypass (RYGB) was used most, worldwide LAGB is still common, as is VBG in a limited number of countries.¹

In previous research, a peak in weight loss during the first postoperative year was followed by a phase of weight regain 1 to 6 years postoperatively, and a relatively stable weight 6 to 10 years postoperatively.⁵ The present results were in agreement with this pattern. However, patient variability was high. In 2005, changes in initial weight varied between 57% decrease and 5% increase. In 2010, this was between a 50% decrease and a 2% increase. Previous long-term studies reported that 20–30% of patients were unsuccessful, when success was defined as weight loss of 30% to 40% of the initial weight or 40–75% EWL.^5,10,21–23 When in the present study, success was defined as a reduction of 30% of initial weight,^11,12 half of the participants were unsuccessful. In 13%, weight loss was less than 10% or participants even regained weight.

An open-ended question on subjective reasons for unsuccessful weight loss included the following answers: difficulties changing eating habits (irregularity, high calorie food, emotional and stress eating, vomiting), physical problems (lungs, thyroid, and hormonal problems), medication (prednisone, antidepressants), and pregnancy. These reasons were in line with the literature.^22–25 In the first year after surgery, type of procedure (44.8%) and baseline weight (18.5%) have been identified as key predictors for successful weight loss.¹² Others report physiological factors,²⁶ inadequate coping strategies to the postoperative diet, a return to maladaptive eating behavior,^22,24 or cognitive impairment²⁷ as risk factors for failure of success.

Reoperations

Reoperations have become an emerging topic because not all patients do well after one operation.²⁸ Previous 5-year follow-up studies reported reoperation rates up to 25%.²⁹ Ten to fifteen years follow-up studies reported rates of 40% depending on the procedure used.^19,30,31

At the 2005 assessment, 14% of the participants reported a reoperation. In 2010, this was 27%. Thus, the reoperation rate was relatively low. In previous research, the most common reasons for reoperation were unsuccessful weight loss or complications (e.g., reflux, ulcers, eroded gastric rings).³² Unfortunately, the present study did not collect information on this. In addition, previous studies showed that the incidence of complications increased with the number of operations.³² Thus, the potential benefit from additional weight loss should outweigh the surgical risk.³³ However, because research on revision patients is scarce, it is difficult for the surgeon to judge the risks and benefits of a reoperation.

Patient satisfaction with the bariatric trajectory

In the present study, at the 2010 assessment, 60% of the respondents were not satisfied with their current weight. They opted for extra weight loss varying between 5 and 60 kg. Despite this, the majority of the participants were satisfied with the total bariatric trajectory; they would opt again for surgery if they knew then what they know now. Thus, not all patients find weight loss the most important factor.^7,8

Few studies have assessed patient opinion. In a 4-year follow-up study, 88.9% strongly agreed that they were satisfied with a RYGB type of surgery overall and 92.6% strongly agreed they would choose to have the surgery again.³⁴ In a recent 11-year follow-up study, 82.3% of the participants would choose the procedure again.¹⁹ In another 11-year follow-up study, 79% of the patients were satisfied after a primary gastric bypass, 21% were not.⁸ In the present study, 18% and 25% in 2005 and 2010, respectively, were not satisfied. Furthermore, we found evidence that reoperation was a risk factor for dissatisfaction, although odds ratios were not statistically significant. A previous study also showed that patient satisfaction after a reoperation was only fair.³⁵

Reoperations, as a rule, have poorer weight results than initial operations with concurrent impact on patient satisfaction. Despite additional weight loss, subjective outcomes like satisfaction may run their own, relatively independent, course.³⁵ More research is necessary to elucidate the impact of reoperation on patient satisfaction. Expectations of the patient may be crucial. Patients' preoperative expectations that life will dramatically change after surgery may have a negative impact on psychological health if postoperative results mismatch expectations, despite significant weight loss.³⁶ It is crucial to discuss expectations before surgery and to provide realistic information, for example, by providing evidence-based reoperation rates. This way, subjects can weigh their decision before entering a bariatric trajectory.

Methodological issues and future directions

The present study added information to the small pool of long-term results and, in particular, to the even smaller pool of results regarding patient satisfaction. Nevertheless, the present article has some limitations.

First, sample size was relatively small. Thus, results are explorative and need to be replicated. Furthermore, because power was low, not all reported associations reached statistical significance. The small sample size was the main reason not to exclude the six participants who had postponed surgery and, therefore, were fewer than 5 years postoperative at the 2005 follow-up. Including all 490 patients referred to the department was not feasible within the available resources.

Second, patients may over-report positive medical outcomes or under-report negative outcomes.³⁴ Although these phenomena cannot be excluded, the current results match other long-term studies that did include objective weight assessment. The focus of the present study was on patient-centered outcomes. Therefore, to increase the response rate, questionnaires were used rather than assessment at the hospital. Those self-reported measures have been proven valid; self-reported weight and height were highly correlated with objective measures.³⁷

A third limitation is the relatively high loss to follow-up. In previous research, patients lost to follow-up tended to lose less weight, revealing the importance of complete follow-up. This creates a particular challenge, as it is likely that patients with less positive results are the most uncooperative to engage in follow-up procedures.³⁸ Fortunately, baseline weight and BMI, as well as weight change between baseline and the 2005 assessment, did not differ between 2010 responders and nonresponders (137 kg vs. 131 kg, 46 vs. 47, and −38 vs. −38, respectively), but 2010 nonresponders more often had a reoperation at the 2005 assessment (42% vs. 20%). Because of the relatively low number of participants and the explorative character of the study, sensitivity analyses using the intention to treat principle were not performed. Future larger studies should perform sensitivity analyses to examine potential bias due to differential attrition.

Finally, we validated the satisfaction outcome by analyzing the associations with valid concepts such as weight loss, reoperation, and type of procedure. This was in agreement with expectations.^8,34,35

Conclusions

From the patient's perspective, success of bariatric procedures involves more than weight loss. In this study, 74% again would choose a bariatric route, regardless of type of surgery, although only 40% was satisfied with their current weight. Reoperations seemed to reduce satisfaction. More research is necessary to replicate these results and to reveal the patient-specific factors that determine satisfaction. If we can clarify the factors of (dis-)satisfaction from the patients' perspective, we can better understand how to set expectations. Definitions of success should be based on provider perspective as well as patient perspective. Patients should be informed about the high variability in postoperative weight loss and the substantial risk for reoperation to optimize the patient's decision and reduce the risk of unrealistic expectations and dissatisfaction.

Footnotes

Acknowledgments

There was no external funding for this study. The authors thank Anouska van den Heurik, a psychology trainee, for her help in collecting the data and Bernadette van Velzen for checking the data set. Written informed consent was obtained from all individual participants included in the study.

Authors' Contributions

G.K. contributed to conception and design, as well as acquisition of data; she performed statistical analysis and drafted the article. M.D. has made substantial contributions to the statistical analysis and has been involved in revising the article critically for important intellectual content. R.S. has made substantial contributions to conception and design and has been involved in revising the article critically for important intellectual content. G.V. helped with the interpretation of data and has been involved in revising the article critically. J.v.O. and R.P. have made substantial contributions in revising it critically for important intellectual content. All authors read and approved the final version.

Author Disclosure Statement

No competing financial interests exist.

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