Medical and Psychological Predictors for Long-Term Bariatric Success Using Primary Vertical-Banded Gastroplasty as a Model

Abstract

Introduction:

Bariatric surgery requires patients to implement permanent lifestyle changes that are affected by several factors. Psychological assessment seems to be essential for optimal weight loss and maintenance. The burden remains in identifying potential psychosocial predictors that might influence the long-term outcome. Therefore, this study was designed to identify those predictors for the long-term outcome after primary vertical-banded gastroplasty (VBG).

Methods and Design:

Patients who underwent primary VBG between 2001 and 2004 completed a number of psychological questionnaires. Additional postal questionnaires were sent to retrieve the latest medical outcome. Patients were categorized as failed or successful based on their excess weight loss at last follow-up.

Results:

This study identified a number of potential predictors. Failed patients showed more esthetic expectations, a more dominant character, more work absenteeism before surgery, and depend more on the procedure than successful patients (SPs). SPs showed that positive emotions are an inhibitory factor for eating and less underwent revisional surgery.

Conclusion:

This study shows a number of possible predictors, mainly found in the patient's character. The best way to prevent these predictors seems to be early recognition in the preoperative phase and a structured postoperative psychological follow-up to tackle any potential problems at an early stage.

Introduction

Bariatric surgery has become an increasingly popular treatment option for morbid obesity. In 2011, more than 340,000 procedures were performed, a number that is currently still growing.¹ These days, bariatric surgery is not solely performed to achieve long-term weight loss anymore, as more patients are operated for metabolic diseases such as diabetes mellitus type 2.^2,3 Bariatric surgery requires patients to implement permanent lifestyle changes to achieve long-term successful outcomes.⁴ These lifestyle changes are affected by several nonsurgical factors such as eating behavior, personality, socio-economic status, and coping.^5–7

Psychological assessment both pre- and postoperative appears to be essential to guarantee an optimal weight loss and weight loss maintenance after bariatric surgery.⁸ However, there are still countries in which the role of the mental health providers is not well defined and the psychological support is not standard in the current postoperative standard package of care.⁹

Results are contradictory and far from conclusive and there is no general consensus on which psychological factors may predict the outcome after bariatric surgery. The challenge remains in identifying these potential psychological factors that might influence the long-term outcome.¹⁰ An important impediment is the overall methodological weakness, the different outcome measures for success, small patient groups, and diverse lengths of follow-up of the current literature to find reliable and valid predictors for the outcome of various bariatric procedures.⁶ There are various bariatric procedures: malabsorptive procedures such as Roux-en-Y gastric bypass (RYGB) and duodenal switch and restrictive procedures such as adjustable gastric banding, sleeve gastrectomy (SG), and vertical-banded gastroplasty (VBG). The VBG is an old restrictive procedure, originally invented by Mason et al. and later altered by MacLean.^11,12 Studies on this procedure show good short-term results; however, long-term results were more heterogeneous, which eventually led to the abandonment of this procedure in the Netherlands some years ago.^13–15

Research on early postoperative predictors was published by a part of the current group.^6,16,17 The current study was designed to identify potential psychosocial predictors for the long-term outcome after primary VBG.

Methods and Design

Methods

Between January 2001 and November 2004, bariatric patients undergoing VBG at the Obesity Center, Catharina hospital, Eindhoven, the Netherlands, were included and asked to complete several questionnaires preoperatively and 6 months, 1 one year, and 2 years postoperatively. All patients undergoing primary VBG were included.

The questionnaires included questions to assess personality, eating behavior, obesity-related beliefs, health-related quality of life, body attitude, psychological and somatic symptoms, and coping. All questionnaires are displayed in Table 1. Furthermore, patients were asked to complete questions on motivation, expectations, the history of their obesity, eating behavior, and several eliciting and inhibitory factors with regard to eating.

Table 1.

Psychological Questionnaires

Symptom checklist	SCL-90 ³¹
Dutch personality questionnaire	DPQ³²
Dutch eating behavior questionnaire	DEBQ³³
Body attitude test	BAT³⁴
RAND-36 health survey	RAND-36³⁵
Amsterdam biographical questionnaire	ABQ^a,36
Eating disorder inventory II	EDI-II^a,37
Utrecht coping list	UCL^a,38
Multidimensional health locus of control scale	MHLC^a,39
Multidimensional health locus of control-obesity	MHLC-obesity^a,40
Overweight cognition questionnaire	OCG^a,41

Questionnaires only administered preoperatively.

Since the end of the year 2011, follow-up is a structured 5-year program at this center. However, patients participating in this study underwent limited follow-up during 1 year in the hospital, after which they were referred back to the general practitioner in case of no complaints after 1 year. To retrieve all medical outcomes and the latest follow-up, all medical charts were reviewed and all patients who underwent primary VBG in this center received a postal questionnaire. Nonresponding patients received a phone call. In case of nonresponse, the last known follow-up out of the medical charts was used.

The postal questionnaire was designed to retrieve the current and the lowest weight after surgery, current status of obesity-related comorbidities, and use of medication, revisional surgery when applicable, and long-term complaints. Complaints were categorized into dysphagia, frequent vitamin deficiencies, incisional hernia, and other complaints with an open text field.

The comorbidities were categorized into resolved (treatment no longer needed), improved (diminished amount of medication and/or use of Continuous Positive Airway Pressure (CPAP) in case of sleep apnea), stable, worsened, or de novo. Patients reporting complaints were invited for additional analysis at the outpatient clinic.

Based on their last follow-up data, patients were categorized, depending on the percentage of excess weight loss (%EWL), as failed patient (FP; <50%), or successful patient (SP; ≥50%). These percentages are used in the Reinhold criteria, which state that a bariatric procedure is considered successful when a %EWL is achieved of at least 50%.¹⁸ Patients necessitating revision were considered FPs, unless there was an evident technical cause for failure. In case of technical failure, patients were considered failed or successful based on the %EWL at last follow-up after VBG.

For this study, analysis of all preoperative questionnaires was performed to identify possible predictors for long-term success after primary VBG. Long-term results after VBG were completed with the use of the additional postal questionnaires.

Treatment

All patients were evaluated at the outpatient clinic for eligibility for bariatric surgery by a dietitian, a bariatric nurse, and a psychologist. When eligible for surgery, patients were asked to fill in all preoperative questionnaires. Surgery was performed by hand-assisted laparoscopic approach. A transgastric window was created, using a CEEA21 stapler (Covidien, New Haven, CT), about 6 cm distally from the gastroesophageal junction along the lesser curvature. An oral gastric tube Ch34 was placed between the lesser curvature and the circular stapler. Hereby, the pouch size is ∼1.2 cm in length, measured from the gastroesophageal junction. Along this tube, a vertical staple line was created from the transgastric window toward the angle of His using an EndoGIA (Covidien). For the final step of this procedure, a polytetrafluoroethylene band (1.5 × 7.5 cm) was wrapped around the distal end of the gastric pouch, using the gastric tube for calibration. At a circumference of 6 cm, the band is fixed using two nonabsorbable sutures.

Statistical analysis

Collection, management, and analysis of all data were done retrospectively using SPSS version 22, for Windows (SPSS, Inc., Chicago, IL). Quantitative data are denoted as mean ± standard deviation, whereas nominal data are denoted as a percentage. The Mann–Whitney U-test was used to determine any significance of the observed differences among groups. Statistical significance was identified when the p value was less than 0.05. Summative figures and tables were used where necessary.

No ethical approval was required for this study and this study was performed according to the principles of the Declaration of Helsinki. Informed consent was obtained from subjects.

Results

A total of 98 patients were eligible for inclusion for this study. Seventy patients (71.4%) completed and returned their postal questionnaires. The other 28 patients did not complete the questionnaire after postal nonresponse. Eighteen phone numbers were out of order, one patient refused cooperation, and nine patients could not be reached on multiple occasions. The total group showed an average total follow-up of 106.9 ± 49.3 months with an average total %EWL of 52.9% ± 27.8% at last follow-up after VBG. When classifying patients as described in the Methods and Design section, 62 FPs and 36 SPs were identified. Table 2 displays the baseline characteristics.

Table 2.

Baseline Characteristics (n = 98)

	Failed patients N = 62 (63.3%) Mean ± SD	Successful patients N = 36 (36.7%) Mean ± SD	p
Age (years)	39.4 ± 8.5	39.3 ± 7.7	0.836
Male: Female (n)	9: 53	2: 34	0.319
Body mass index before VBG (kg/m²)	46.4 ± 5.3	44.3 ± 4.4	0.039
Preoperative comorbidities
Diabetes mellitus type 2 (n)	7	4	1.000
Hypertension (n)	15	9	0.929
Dyslipidemia (n)	3	1	1.000
Sleep apnea (n)	1	0	1.000
Osteoarticular disease (n)	6	1	0.256
Operative time (min)	94.4 ± 24.2	90.3 ± 18.5	0.599
Length of hospital stay (days)	3.1 ± 1.2	3.1 ± 1.0	0.906
Number of patients with ≥1 comorbidity (n)	24	13	0.798

VBG, vertical-banded gastroplasty.

Medical results

Shown in Table 3 are the medical results at last known follow-up after VBG and after revision, including follow-up, %EWL, number of revisional procedures, and the presence of any comorbidities. Furthermore, the table shows the %EWL as expected preoperatively by the patients. Patients who underwent revision had either a revision of the primary VBG (n = 3), conversion to SG (n = 2), or conversion to RYGB (n = 18). The main reason for revision in the entire study population was weight regain (47.8%), which in one case was caused by an evident technical cause (band dehiscence). Mean %EWL of the total population at last known follow-up including any necessitated revision was 60.7% ± 20.8%.

Table 3.

Medical Results at Last Follow-up (n = 98)

	Failed patients N = 62 (63.3%) Mean ± SD	Successful patients N = 36 (36.7%) Mean ± SD	p
Mean follow-up without revision (months)	95.7 ± 48.3	87.4 ± 58.0	0.527
Mean EWL without revision (%)	30.4 ± 18.0	74.1 ± 25.1	<0.001
Number of revisions (n)	20	3	0.007
Mean total follow-up (months)	115.1 ± 42.4	92.9 ± 57.2	0.143
Mean EWL at last follow-up (%)	39.0 ± 23.0	77.5 ± 15.8	<0.001
Number of patients with ≥1 comorbidity	10	3	0.362
Expected EWL before surgery (%)	79.3 ± 22.7	84.3 ± 26.2	0.369

EWL, excess weight loss.

Questionnaires

Results of all questionnaires mentioned in the Methods and Design section were reviewed for potential predictors. Table 4 shows the clinically relevant and the significantly different parameters of the various questionnaires. No significant differences were seen between the two groups in the SCL-90 subcategories, the UCL, the EDI (assessing the level of emotional eating), the MHLC, the NVE, and the OCL-25.

Table 4.

Results Psychological Questionnaires (n = 98)

		Failed patients N = 62 (63.3%) Mean ± SD	Successful patients N = 36 (36.7%) Mean ± SD	p
SCL-90	Psychoneuroticism	139.0 ± 39.4	145.5 ± 45.2	0.611
DPQ	Dominance	14.8 ± 6.5	12.1 ± 5.8	0.049
ABV	Work absenteeism (days)	24.3 ± 58.4	18.8 ± 65.9	0.025
LAV	Total score	65.5 ± 15.2	63.9 ± 17.1	0.622
RAND-36	Role limitations (emotional)	5.5 ± 1.0	5.0 ± 1.2	0.032
RAND-36	General perception of health	15.0 ± 3.9	14.9 ± 3.8	0.804
MHLC-obesity	Doctor as locus of control	11.4 ± 2.5	12.7 ± 3.0	0.038

Motivation

Patients were presented a number of options on what motivated them to lose weight and what motivated them to choose for a bariatric procedure. These questionnaires were answered in a yes/no format. Options on motivations to lose weight were health, limitations in movement, social reasons, esthetic reasons, condition, dissatisfaction with body, and other psychic reasons. Motivations on choosing a bariatric procedure were insufficient results with other weight-losing methods, lasting weight reduction, the ability to eat less, surgery acting as a driving force, and faster satiety.

No significant differences were found in any of the options between the two groups. Regrouping the motivations did not change the outcome between the two groups.

Expectations

The questions on expectations were similar to those on motivation. Options on expectations of the effects of the bariatric procedure were faster satiety, change of eating pattern, a happier life, lasting weight reduction, procedure acting as a driving force, increased activity, the ability to buy new clothes, and other expectations. The study showed that patients in the FP group were significantly more often expected to be able to buy new clothing (p = 0.004). No significant differences were seen with respect to the other expectations.

History of patients' obesity

All patients were asked about their weight status (underweight, normal weight, and overweight) during various life phases. No significant differences were found between the two groups. Furthermore, no significant differences were seen in the causes for the obesity, such as pregnancy, a medical reason, eating pattern, or genetic predisposition.

Eliciting and inhibitory factors

There can be many eliciting as well as inhibitory factors for eating more than normal. Several eliciting factors were reviewed; however, no factors were significantly different between the two groups. A few only showed a trend to occur more often in the FP group, such as social activities (p = 0.074) and the confrontation with food (p = 0.088). Other factors reviewed were emotions, boredom, social control, watching television, time to eat, and appetite. Inhibitory factors were positive and negative emotions, dieting, social control, and work. A significant difference was seen in the positive emotions (p = 0.024) in favor of the SP group. No significant differences were seen for the other inhibitory factors.

Eating behavior

No significant difference was seen in the occurrence of binge eating or grazing between the two groups. Furthermore, no differences were seen between two groups when assessing number of meals, number of snacks, and the amount of calories. Eating has many functions. This study assessed eating to attenuate (negative) emotions, to maintain positive emotions, satiety, distraction, habit, sociability, to stay alive, and as a reaction to problems. No significant differences were seen between groups on incidence of these various functions.

Discussion

This study was designed to find potential predictors for long-term success after primary VBG, an old restrictive procedure achieving an average %EWL of up to 60%.¹⁹ Of all patients, 63.2% were considered a FP, underlining the inferiority of this procedure as shown in other studies before.^13–15 Partly, failure may be imputed to the limited follow-up these patients had postoperatively, even though literature suggests a high long-term complication rate after VBG and a high rate of revision. As stated before, identifying predictors on the outcome after bariatric surgery remains a burden. Therefore, this study was set up to find either medical or psychosocial predictors on the long-term success after a primary bariatric procedure.

Considering the medical results, it is noteworthy that the preoperative body mass index (BMI) is significantly higher in the FP group. This might suggest that a higher BMI compared with a lower BMI within the group of eligible bariatric patients may increase the chance of failure in terms of long-term %EWL, supporting multiple previously reported results.^20,21 Even though the initial BMI influences the amount of excess weight and thus the percentage of %EWL, this study shows far better results in the SP group.²² %EWL at last follow-up was nearly twice as much in the SP group as opposed to the FP group. This study shows more revisional procedures in the FP group, which is explained by the occurrence of failure and the way of categorizing patients. The best option for failed procedures is a revisional procedure, so it seems only logical that the revision rate is higher in the FP group.

Other medical and demographic parameters such as comorbidities, gender, excess weight, length of hospital stay, and operating time do not seem to be a predictor for the long-term results in this study population.

Considering the patients' preoperative motivation for losing weight and choosing for a bariatric procedure, no significant differences were found. This suggests that various reasons for losing weight or for choosing a bariatric procedure are no predictor for the outcome after primary VBG in this study. Previous studies, however, have shown that a poor health as motivation can be a potential predictor for long-term success.²³ It remains to what extent the reason for losing weight is related to the cause of the developed obesity. This study showed no differences between the groups in terms of reasons for obesity.

In terms of preoperative expectations, the only potential predictor may be the fact that patients in the FP group significantly more often expected to buy new clothing in the postoperative phase, a pure esthetic expectation of the procedure. This supports old data published on esthetic expectations after bariatric surgery, stating that patients with a lower %EWL more often have high esthetic expectations as opposed to SPs.²⁴ No differences were seen in expected %EWL before surgery between the two groups.

The studied population showed a similar weight history. The phase in which the overweight developed did not differ significantly between the FP group and the SP group. Furthermore, no differences were seen in terms of various options or number of weight loss attempts, which strengthens previous results on weight loss attempts before bariatric surgery.²⁰

There are many known eliciting factors for (excessive) eating, with emotions being a common factor. Multiple studies have shown that emotional eating has either no effect or a negative effect on postoperative weight loss.²⁰ This study showed that emotions as a eliciting factor for eating had no influence on the long-term success after primary VBG.

A significant difference was found for the predictive value of positive emotions as an inhibitory factor for eating in favor of the patients in the SP group. It may be expected that the vast majority of patients have more positive emotions after bariatric surgery, since bariatric procedures have shown to improve quality of life, body dissatisfaction, depression and anxiety symptoms, and eating disorders.^16,25–27 It furthermore can be expected that patients will be confronted with more positive emotions postbariatric surgery and thus, in patients reporting positive emotions as an inhibitory factor, might lead to a higher %EWL.

This study showed no predictive value in any of the parameters regarding eating behavior. Eating behavior, in terms of amount of calories, number of meals per day, binge eating, grazing, and function of eating, will have a no predictive value on the long-term %EWL after primary VBG based on the results from this study. The literature is diverse on the effect of mainly eating and grazing. Some studies report a negative relationship between binge eating and %EWL, others do not report binge eating as a negative predictive value.^28,29 This study does not show a negative predictive value of binge eating.

Several questionnaires were used in this study. Only a few potential predictors can be pointed out with the current results. These results suggest that a more dominant character according to the Dutch personality questionnaire leads to an inferior long-term %EWL. A dominant character is confident, authoritarian, and likes to make its own decisions. Earlier studies showed no predictive value for short-term %EWL, using the same questionnaire.²¹

Patients in the FP group showed a higher rate of work absenteeism 1 year before bariatric surgery. A possible explanation for this outcome may be a poorer physical or mental state of the patient before surgery; however, this hypothesis is not supported by the other results on physical and mental health in this study and extensive research showed no previous data on this specific subject.

Multiple studies have shown that an emotional eating pattern is a possible negative predictor for weight loss, whereas others support the current results, in which no predictive value on weight loss was found for emotional eating.²⁰

A striking finding is the fact that SPs in this study believe that the VBG is significantly more responsible for long-term success as opposed to the FP group, according to the multidimensional health locus of control (MHCL)-obesity questionnaire. A result suggesting that SPs place the long-term outcome more in the hands of the doctor and thus appear to be more receptive to lifestyles changes necessitated for long-term successful weight loss. It is strongly suggested that postoperative weight loss is largely dependent on making and sustaining changes in eating and physical activity.³⁰ This finding strengthens the belief that psychological follow-up is important for the long-term success after bariatric surgery. Furthermore, it appears of the utmost importance that patients are well informed preoperatively that lifestyle changes are a key factor in achieving a successful long-term excess weight loss.

Results from this study should be interpreted with caution when translating them to current practice. A VBG is an old procedure, only a few are performed nowadays since this procedure is surpassed by newer options like the adjustable gastric band and the SG.¹ However, the authors who believe that this group of bariatric patients is not different to any other patient group undergoing a more modern restrictive procedure. Disadvantages of this study are the limited number of patients, the retrospective design of the study, and the low frequency follow-up after surgery, which may have influenced the results. More intensive follow-up might have improved the long-term success rate and thereby have changed the categorization of patients in this study. An advantage of this study is the fact that it is not a controlled trial and it might thereby be a better reflection on everyday practice.

Nowadays, psychological assessment has found a permanent place in both the preoperative and the postoperative phases of a bariatric procedure. Be that as it may, it remains a burden to find potential hazards for poor long-term outcome after bariatric surgery.

When analyzing the possible predictors for long-term success, it seems that predictors for successful %EWL can mainly be found in the patient's character. This study showed more than five possible psychosocial predictors and it seems impossible to tackle all of them preoperatively. Obviously, preoperative psychological screening remains inevitable for identifying known contraindications for bariatric surgery and possible predictors for the long-term outcome, but structured psychological follow-up seems more important to improve the rate of long-term success after bariatric surgery. Evidence on predictors remains limited and more elaborate research and prospective studies are necessitated to gain more evidence on this subject.

Conclusions

This study shows a number of possible predictors, mainly found in the patient's character, and the best way to prevent these predictors seems to be early recognition in the preoperative phase and a structured postoperative psychological follow-up to tackle any potential problems at an early stage.

Footnotes

Author Disclosure Statement

No competing financial interests exist.

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