Effect of bariatric surgery on anxiety symptoms in morbidly obese patients: A systematic narrative literature review Mittmann G, Schuhbauer M, Schrank B, Steiner-Hofbauer V,

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Effect of bariatric surgery on anxiety symptoms in morbidly obese patients: A systematic narrative literature review

Gloria Mittmann¹, Moritz Schuhbauer¹, Beate Schrank², Verena Steiner-Hofbauer¹
¹ Research Centre Transitional Psychiatry, Karl Landsteiner University for Health Sciences, Krems, Austria
² Research Centre Transitional Psychiatry, Karl Landsteiner University for Health Sciences, Krems; Department of Psychiatry and Psychotherapeutic Medicine, University Clinic Tulln, Tulln, Austria

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Date of Submission	14-Feb-2023
Date of Acceptance	31-Mar-2023
Date of Web Publication	26-May-2023

Abstract

Correlation between bariatric surgery (BS), weight loss, and alleviation of anxiety symptoms has been assessed frequently. Research indicates a rather positive effect on anxiety symptoms for the first 3 years after surgery. Beyond this time frame, alleviation of symptoms becomes less apparent. The aim of this study was to investigate the connection between anxiety and BS based on the following research question: does BS lead to an alleviation of their anxiety symptoms in adults with morbid obesity and anxiety symptomatology? The basic mechanism underlying this study was a comprehensive literature search in PubMed and PsycINFO, combining search terms for “anxiety” with “bariatric surgery” related terms. The data set resulting from this search was assessed for relevant studies, which were the basis for the following narrative literature review. A set of 30 studies, 24 prospective cohort studies, and 6 literature reviews met inclusion criteria.The studies included 2228 participants (81% female). At baseline, mean age was 41.4 years and mean body mass index (BMI) was 47 kg/m². The mean BMI at the end of the studies was 34 kg/m². Different BS techniques were used for weight loss. A trend for change in anxiety at different time points postsurgery seems to exist. No clear statement can be made about a correlation between weight loss and alleviation of anxiety symptoms. Some studies found a significant correlation between the two parameters for up to 4 years; however, just as many studies found no correlation. The type of weight loss surgery utilized does most likely not determine the effect on anxiety symptoms. BS should not be thought of as a therapy method for anxiety.

Keywords: Anxiety, bariatric surgery, obesity, weight loss

How to cite this URL:
Mittmann G, Schuhbauer M, Schrank B, Steiner-Hofbauer V. Effect of bariatric surgery on anxiety symptoms in morbidly obese patients: A systematic narrative literature review. J Bariatr Surg [Epub ahead of print] [cited 2023 Sep 29]. Available from: http://www.jbsonline.org/preprintarticle.asp?id=377651

Introduction

Obesity and mental health disorders are both common noncommunicable diseases and are recently being studied in their correlation to one another.^[1] Especially during the severe acute respiratory syndrome coronavirus type 2 pandemic, concerns were raised that both of these noncommunicable diseases will experience a rise in number of cases.^[2] An individual is considered obese when the body mass index (BMI) is equal to or >30 kg/m² and morbidly obese when the BMI is equal to or exceeds 40 kg/m². A drastic but effective measure in reducing the body weight of a patient, who has been unable to reduce weight with behavioral or other noninvasive measures, is bariatric surgery (BS). The primary goal is to reduce the weight of patients over a longer period. Therefore, these operations are also referred to as weight loss surgeries. In many cases, weight is successfully reduced, even lifelong, and BS leads to a reduction of risk for adverse events and improvement or prevention of associated metabolic diseases.^[3] Research has shown that morbid obesity does not only pave the path for physiologic malfunctions but also for psychiatric diseases. This population suffers more frequently from certain mental illnesses such as anxiety, mood, and binge-eating disorders.^[4],[5],[6] The link between obesity and depression has already been established and investigated quite thoroughly,^[7] and studies indicate that a decrease in body weight due to BS can have a beneficial effect on depressive symptoms.^[8] The primary aim of BS in obese patients is usually not to improve their mental health but to reduce weight and therefore may influence the overall health-related quality of life (HRQOL) including several aspects, such as anxiety disorder. Anxiety disorders are one of the major mental health issues in this population.^[6] Anxiety disorders are defined as “excessive fear and anxiety and related behavioral disturbances, with symptoms that are severe enough to result in significant distress or significant impairment in personal, family, social, educational, occupational, or other important areas of functioning,”^[9] which is often related to elevated sensitivity to threats.^[10] Even though a link between depression and obesity^[11] is better understood than for anxiety disorder and obesity, an effect of BS on anxiety appears clinically plausible and warrants investigation. We add evidence to some earlier reviews that included anxiety disorders in their more general mental health outcomes (e.g.^[12]), with the aim to exclusively and specifically determine the course of anxiety symptoms in morbidly obese patients who underwent BS.

Methods

Search strategy

Several preliminary literature searches were performed to obtain an overview of the topic and the amount of available literature. The initial idea was to use the three most important terms from the research question, namely “BS,” “anxiety,” and “obesity,” and find related terms. Since BS and obesity are closely connected, we omitted the search term “obesity.” Blocks for both “anxiety” and “BS” consisted of strings identified in our preliminary searches (searched for on title/abstract level) as well as strings identified from the Medical Subject Headings (MeSH), which resulted in the following final search string:

(“anxiet*”[Title/Abstract] OR “fear*” [Title/Abstract] OR “generalised anxiety disorder” [Title/Abstract] OR “generalized anxiety disorder” [Title/Abstract] OR “phobi*” [Title/Abstract] OR “panic*” [Title/Abstract] OR “Agoraphobia” [Title/Abstract] OR “social anxiety disorder” [Title/Abstract] OR (“Anxiety Disorders” [MeSH Terms: noexp] OR “Panic Disorder” [MeSH Terms] OR “Phobic Disorders” [MeSH Terms] OR “Agoraphobia” [MeSH Terms] OR “Fear” [MeSH Terms])) AND (“Bariatric Surgery” [Title/Abstract] OR “weight loss surgery” [Title/Abstract] OR “Gastric Bypass” [Title/Abstract] OR “roux-en-Y gastric bypass” [Title/Abstract] OR “sleeve gastrectomy” [Title/Abstract] OR “gastric banding” [Title/Abstract] OR “intragastric balloon” [Title/Abstract] OR “biliopancreatic diversion” [Title/Abstract] OR (“Bariatric Surgery” [MeSH Terms: noexp] OR “Gastric Bypass” [MeSH Terms] OR “Gastroplasty”[MeSH Terms] OR “Jejunoileal Bypass” [MeSH Terms] OR “Bariatric Medicine” [MeSH Terms])) AND (“English” [Language] OR “german” [Language])

The final search results were checked for studies which were identified beforehand as relevant via manual searches. This ensured that the search was neither too broad nor too specific. The literature identified through reference lists of included sources was added.

Eligibility criteria

Eligibility criteria can be found in [Table 1]. We used relevant criteria based on the Population-Intervention-Comparison-Outcome format, along with “study design,” “setting,” “time frame,” and “language.”

Table 1: Eligibility criteria

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Data management

The databases PubMed and PsycINFO were used. After the search, all results were stored in EndNote for data management. Duplicates were removed. The first round of screening included title and abstract screening to exclude any papers that did not fit the eligibility criteria. The selection process can be found in [Figure 1]. All included articles after full-text screening were synthesized in an Excel table, and the following 11 items were extracted: first author, publishing year, sample size, distribution between sexes, mean age at baseline, mean BMI at baseline, type of bariatric procedure, final BMI or weight change, anxiety assessment methods, and change in anxiety symptoms over the duration of the study [Table 2].

Figure 1: Flowchart of the selection process

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Table 2: Data synthesis table sorted according to latest assessment time point

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Results

Search results

The database searches yielded a total of 672 results (PubMed: 488, PsycINFO: 184). After the removal of 107 duplicates, a total of 565 articles remained. The process of inclusion and reasons for exclusion can be found in the flowchart [Figure 1]. The final set of included 30 studies was composed of 24 prospective trials^{[6],[13],[14],[15],[16],[17],[18],[19],[20],[21],[22],[23],[24],[25],[26],[27],[28],[29],[30],[31],[32],[33],[34]} and 6 systematic literature reviews.^{[12],[35],[36],[37],[38],[39]} Of the 24 trials, only 3^{[5],[29],[30]} were controlled trials.

Weight loss

All studies found a significant reduction in weight or BMI in their surgically treated groups. This emphasizes the enormous effectiveness of BS in the reduction of excessive body weight in morbidly obese patients.

Change in anxiety symptoms

Up to 6 months after bariatric surgery

Seven studies were found for this category. At this point in time, postsurgery research indicates a rather positive effect on anxiety. Five studies document a statistically significant improvement in anxiety symptoms.^{[5],[16],[26],[28],[33]} Bužgová et al.^[15] found a significant reduction in the Hospital Anxiety and Depression Scale-Anxiety Subscale (HADS-A) scores assessed in a patient group who underwent SG and insignificant changes in the greater curvature plication (GCP) group. Results of Matini et al.^[23] and Hilgendorf et al.^[18] did not reach statistical significance for changes in anxiety.

Up to 1 year after bariatric surgery

Fifteen studies report results for up to 1 year. Research up to 1 year post-BS presents ambivalent findings. Significant changes in anxiety symptoms 1 year after BS were reported in six different studies.^{[5],[13],[14],[16],[27],[34]} No significant changes were documented in four studies.^{[6],[18],[31],[32]} One study^[31] presented promising data from three groups using three different BS techniques (GB, Roux-en-Y gastric bypass [RYGB], and biliopancreatic diversion). A reduction in anxiety scores, measured by the State-Trait Anxiety Inventory, was found in every subgroup, but none reached P values of statistical significance. The study by Bužgová et al.^[15] found a significant alleviation of the HADS-A score in the SG group and insignificant changes in the GCP group after 12 months. A particular improvement in symptoms seemed to take place in phobias, since three studies mentioned statistically significant improvement.^{[21],[24],[34]} Lier et al.^[21] found social phobia as the most common axis I diagnosis within 19% of their sample. The prevalence of phobia and panic disorder decreased significantly, but not the Beck's Anxiety Inventory (BAI) score and the prevalence of agoraphobia and generalized anxiety disorder. Papageorgiou et al.,^[24] who documented significant improvement in phobic anxiety, did not witness alleviation in the overall anxiety scores. Wei et al.^[28] found a significant reduction in anxiety scores, measured by HADS-A, with the lowest scores after 3 months and subsequent rise back to baseline levels at 12 months post-BS.

Up to 2 years after bariatric surgery

Thirteen studies were found in this category. Six studies^{[6],[16],[17],[22],[25],[27]} revealed a statistically significant reduction in anxiety symptomatology 2 years after BS. In the sample of Hayden et al.,^[17] the diagnosis of an anxiety disorder before BS did not predict a disorder 2 years after. This statement is contradictive to the findings of De Zwaan et al.,^[32] who found that preoperative anxiety disorder predicts the presence of anxiety disorder at both assessment time points, i.e., 6–12 months and 24–36 months after BS. Another study with significant results, measured by the Symptom Checklist-90-R, indicates a reduction in anxiety symptoms after 2 years.^[22] Nonsignificant results were also observed at this interval.^{[14],[18],[32]} Aasprang et al.^[13] did not provide information about statistical significance at this time interval but showed trends toward the reduction of anxiety symptoms. Kalarchian et al.^[20] found a reduced point prevalence of anxiety disorders, i.e., social phobia, specific phobia, and posttraumatic stress disorder via SCID-I but provides no significant P values for the reduction of prevalence. Karlsson et al.^[5] found an increase in anxiety at years 2 and 3 even though prevalence was still lower than presurgery.

Up to 3 years after bariatric surgery

Five studies looked at changes up to 3 years. Kalarchian et al.^[20] and Nickel et al.^[29] document statistically significant changes in anxiety 3 years after BS. Additionally, Nickel et al.^[29] did not witness a reduction in anxiety in the control group undergoing conventional therapy. Their BS patients also displayed a tendency toward increased employment and initiating partnerships. Kalarchian et al.^[19] report a lower prevalence for anxiety disorder in year 3 though no significance level was reported. De Zwaan et al. and Karlsson et al.^[5],[32] found a lower prevalence of anxiety after 3 years, but this did not reach statistical significance. A point which was made twice in studies concluding after 3 years was that presurgery anxiety, lifetime or present during presurgery assessment, predicted anxiety disorder even at this interval postsurgery.^[20],[32] Lifetime anxiety disorder seemed to negatively impact weight loss, whereas anxiety at preoperative assessment did not.^[32]

Up to 4 years after bariatric surgery

From the four studies that were found for the period up to 4 years after BS, one study^[30] supports the hypothesis of positive effects of BS on anxiety disorder, defined as a reduction in BAI and HADS-A, respectively. Burgmer et al.^[14] found a slight decrease in HADS-A scores but could not demonstrate statistical significance. Twenty-four percent of initially known clinical cases of anxiety disorder recovered, but also 17% developed severe anxiety symptoms throughout the 4 years after BS. Kalarchian et al.^[19] found a significant decrease in the overall prevalence of their assessed disorders (phobic anxiety, specific anxiety, and posttraumatic stress disorder) in the RYGB group of their sample but not in the GB group as measured by SCID-I. Karlsson et al.^[5] found a significant correlation between weight loss and alleviation of anxiety symptoms, as measured by HADS-A, up to 4 years after BS.

Up to 6 years after bariatric surgery

Five studies were found for this category. One study^[30] observed a statistically significant reduction in anxiety symptoms up to this time point. Significant weight loss, increased employment, and increased number of partnered participants were also documented among the 21 patients. Ribeiro et al.^[25] tested for both 24–59 (T2) and 60 (T3) months postsurgery. While there was a significant decrease for T2, no significant reduction could be found at T3. Two studies^[13],[25] were not able to detect significant alleviation of anxiety symptomatology. Kalarchian et al.^[19] found an increase in prevalence of anxiety disorders between years 4 and 5. Karlsson et al.,^[5] who found a significant correlation between weight loss and alleviation of anxiety symptoms for up to 4 years, were not able to detect this correlation anymore from 6 to 10 years after BS.

Up to 10 years after bariatric surgery

Two studies were found for this category. Kalarchian et al.^[19] assessed their patients for up to 7 years after BS with SCID-I. After this time span, there was no significant reduction in the prevalence of social phobia, specific phobia, or posttraumatic stress disorder in their sample. Karlsson et al.^[5] investigated the effects of BS on several mental health and HRQOL aspects up to 10 years after BS. Results were compared to a conventionally treated, similarly obese group of patients. Anxiety symptoms, which were highly elevated in the BS intervention group compared to Swedish norm population at baseline, remained highly elevated after 10 years.

Discussion

This review examined various BS types and their impact on anxiety disorders. However, it is currently unclear which surgery type is most effective in achieving sustainable long-term outcomes for reducing anxiety symptoms. While some studies have reported greater reductions in anxiety symptoms with malabsorptive techniques compared to restrictive ones, the significance of this finding is debatable. Elevated levels of anxiety before surgery may be attributed to the higher health risks and the irreversible nature of these interventions, rather than the surgical technique itself.^[15] A return to normal in anxiety symptoms could then be interpreted as a reduction due to BS. Additionally, when comparing BS intervention groups with conventional weight loss therapy, no difference in effect on anxiety symptoms was apparent after 10 years. Karlsson et al.^[5] compared BS as intervention with conventional therapy; they found better outcomes for depression, psychosocial functioning, and social interaction in the surgical group but no significant differences for anxiety. The improvement of anxiety was not associated with weight loss. Nickel et al.^[29],[30] did not witness a reduction in anxiety in the control group undergoing conventional therapy. In all three studies, the control groups, treated with conventional therapy, showed no significant weight loss. These findings raise the question whether documented alleviation in anxiety by some studies are actual improvements due to surgery, or merely fluctuations over time and suggests that the interaction between weight loss and anxiety remains unclear.

Thus, time was a predictor in the change of anxiety symptoms after surgery, but neither weight loss nor type of BS proved to be indicative.^{[5],[19],[25]} The greatest weight loss takes place during the primary year after BS.^{[5],[14],[16],[29]} Evidence of a phase of maintenance up to the 2^nd year postsurgery exists.^[14],[25] At some point, a phase of weight regain follows. This phase lasts until approximately 6 years post-BS.^{[5],[14],[25]} Only one study assessed weight with multiple follow-up times up to 10 years after BS. They documented another phase of weight stabilization which led to an average weight loss of 16% of the initial weight prior to surgery.^[5] A majority of found studies assessing the 1^st year after surgery yielded successful outcomes^{[5],[13],[14],[15],[16],[26],[27],[28]} but no supportive data remained by the interval between 6 and 10 years postsurgery.^{[5],[13],[19]} Kalarchian et al.^[20] found a correlation of weight loss and regain with anxiety symptomatology for up to 4 years after surgery. Beyond this point, weight and anxiety developed independently from each other for up to 10 years^[5] after BS. However, even the correlation for up to 4 years is not unanimous, since several other studies could not identify a correlation at 6 months,^[23] 2 years,^[17] and 4 years^[14] after BS.

Limitations and future directions

A majority of studies comprised a rather small sample size and therefore raised concerns about generalizability of results. Many studies did not mention when the participants underwent anxiety assessment before BS which could have led to elevated anxiety scores if assessed very shortly beforehand. It is likely that the general level of anxiety in the patient samples was artificially increased due to the limited time span between assessment and BS. The article only focuses on the outcome of anxiety symptoms, assessed by standardized questionnaires. Only a few studies supplied information on manifest/diagnosed anxiety disorders and their medication. Thus, we did not assess medication in any study. None of the studies mentioned psychological support since making use of it would falsify the outcome and no definitive effect of BS would be retraceable. Future studies could include medication and/or psychological support during weight loss, and/or after BS, this could lead to valuable insights and optimized outcomes for patients.

Conclusion

BS remains a promising option to reduce overweight in morbidly obese patients. It holds promising benefits for plenty of HRQOL criteria. However, it fails to display definite outcomes for anxiety. In early stages after BS, research suggests a rather beneficial effect for up to around 1 or 2 years after intervention. Yet, it fails to maintain this beneficial effect from approximately 4 up to 10 years after BS. No studies could be found assessing anxiety in BS patients after a time interval of 10 years postsurgery. Due to uncertain effects on anxiety, BS should not be considered the main therapy option for anxiety disorders. In case of considering BS in a morbidly obese patient with anxiety symptoms, improvement of anxiety can be experienced over short-term duration but should not be expected after several years.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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