Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT02775071 |
| Other study ID # |
823735 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
March 3, 2016 |
| Est. completion date |
December 31, 2021 |
Study information
| Verified date |
May 2024 |
| Source |
University of Pennsylvania |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
This study will evaluate the relationship between psychopathology, disordered eating, and
impulsivity (measured by clinical interview, self-report measures, and objective testing) on
changes in weight and psychosocial status in the first two years after bariatric surgery.
Participants will be 300 adults who plan to undergo bariatric surgery. Participants will
complete four assessments over a two-year period, one at baseline (before surgery) and 6, 12,
and 24 months after surgery. Each assessment will include computer tasks, surveys, clinical
interview, urine test, waist circumference and height/weight measurement. The investigators
will track how psychopathology, disordered eating, and impulsivity are related to changes in
weight and psychosocial status following bariatric surgery.
Description:
Psychosocial Status and Psychopathology in Candidates for Bariatric Surgery:
Extreme obesity is associated with a significant psychosocial burden, including impairments in
quality of life, body image, sexual behavior and other areas of psychosocial functioning.
While this distress is believed to contribute to the decision to have bariatric surgery, its
impact on postoperative outcomes is less clear. At present, little is known about the
physiological and behavioral contributions to success or failure of bariatric surgery.
Regardless, weight regain after bariatric surgery is frequently attributed to preoperative
psychosocial and behavioral factors. More specifically, there has been a great deal of
interest in the presence of formal psychopathology in bariatric surgery patients and its
potential contribution to postoperative outcomes. At least six studies have described rates
of psychopathology in candidates for bariatric surgery using structured diagnostic
instruments. Lifetime rates of any psychiatric diagnoses ranged from 36.8%-72.6%, higher than
those reported in most studies of the general population. Mood disorders were the most
frequent diagnoses, seen in 22.0%-54.8% of patients. Substance use disorders (SUDs) were
found in up to 35.7% of patients and alcohol abuse or dependence in up to 33.2%. Binge eating
disorder (BED), defined as eating an unusually large amount of food within a short period of
time coupled with a loss of control over eating, has been diagnosed in 4.6% to 27.1% of
patients. Current diagnoses (as compared with lifetime) were less common, reported in
20.9%-55.5% of candidates for surgery. Mood disorders were diagnosed in up to 31.5%. BED
ranged from 3.4%-41.9%. Current substance use was seen in less than 2% of patients. (Note.
The lower percentages of those with current psychopathology, as opposed to lifetime
psychopathology, are expected.) While studies of the psychosocial characteristics of
bariatric surgery candidates have been informative, they are not without limitations. Many
studies have suffered from methodological concerns, including small sample sizes or lack of
an appropriate comparison group. Further, establishing psychiatric diagnoses prior to
bariatric surgery is challenging. Perioperative guidelines suggest that patients undergo an
evaluation with a mental health professional prior to surgery and most third party payers
require these evaluations. However, most programs do not use structured clinical interviews
to establish diagnoses for clinical purposes. Several studies have suggested that candidates
for bariatric surgery engage in impression management prior to surgery, in which they
minimize reports of psychopathology to present themselves to the bariatric team in the most
favorable light. To address this issue, assessment of psychiatric symptoms for research
purposes is recommended to occur independently from the required clinical evaluation, as the
investigators will do in the proposed study. Nevertheless, studies focusing on the
relationship between specific diagnoses and postoperative outcomes may fail to account for
other psychological constructs that may be shared across diagnoses. Mood disorders, BED, and
SUDs all share the common psychological construct of impulsivity, considered an important
aspect of executive functioning. A lack of impulse control may contribute to the excessive
weight gain seen in extreme obesity and may impact the results of bariatric surgery.
Disinhibition and Impulsivity among Persons with Extreme Obesity; Studies have suggested that
individuals with obesity, and in particular those with extreme obesity presenting for
bariatric surgery, show some deficits in executive functioning. For example, candidates for
bariatric surgery have shown deficits in working memory, mental flexibility, motor speed and
complex attention.These deficits could impact comprehension and retention of information
presented to patients during the preoperative consultation process and, thus, negatively
impact the ability to adhere to the dietary and behavioral changes required for an optimal
postoperative outcome. At the same time, metabolic dysregulation, such as insulin resistance
or hyperglycemeia seen in type 2 diabetes, also is associated with cognitive deficits,
suggesting a potential physiological mechanism for the relationship. Dietary disinhibition,
defined as a loss of control over eating, plays a central role in the overconsumption of food
and, subsequently, the development of obesity. Disinhibition is similar to impulsivity, the
term more commonly used in the substance use and smoking cessation literatures. Impulsivity
is a multi-faceted construct and refers to the absence of the ability to inhibit an automatic
behavior (otherwise known as response inhibition) and the tendency to discount future
consequences in favor of more immediate outcomes (known as delay discounting). Similar to the
role of disinhibition in obesity, impulsivity contributes to the development of and relapse
with SUDs. Indeed, response inhibition and delay discounting are associated with both SUDs
and obesity. Both also predict response to treatment for both SUDs and obesity. Chronic
overeating and binge eating share several neurobiological and behavioral similarities with
SUDs. In this regard, both may be viewed as behavioral disorders, in which intake (of food,
alcohol, and/or drugs) escalates to a rate that is unhealthy and maladaptive. Nevertheless,
the specific nature of the relationship between binge eating and substance use remains to be
fully elucidated. There are similarities between binge eating and addictive disorders,
including craving for the desired substance (drug or highly palatable food), a sense of loss
of control when using, repeated attempts to control use despite clear adverse consequences,
and the dedication of much time in obtaining and using the substance. Thus, the disinhibition
observed with obesity and binge eating, the impulsivity seen with substance use disorders,
and the emotional dysregulation associated with mood disorders all likely share commonalities
that may both contribute to the development of extreme obesity and also may be associated
with weight loss and changes in psychosocial status after bariatric surgery.
Psychosocial Status and Psychopathology after Bariatric Surgery:
In general, individuals who undergo bariatric surgery report dramatic improvements in
psychosocial status and functioning postoperatively. The vast majority of patients report
significant reductions in symptoms of depression and anxiety in the first postoperative year.
They also report significant improvements in health and weight-related quality of life.
Patients also report improvements in body image, sexual functioning, and relationship
satisfaction. The relationship between preoperative psychopathology and postoperative
outcomes is less robust. Livhits and colleagues reviewed this literature and concluded that
the preoperative factors of BMI, BED, and the presence of personality disorders provided the
strongest negative associations with postoperative weight loss. At least two studies have
suggested that preoperative psychopathology, particularly mood and anxiety disorders, is
associated with smaller weight postoperative weight losses. The relationship between BED and
postoperative weight loss is unclear; some studies have found a relationship between
preoperative BED and postoperative weight loss while others have not. Additionally, two
studies have suggested that a history of substance abuse is associated with larger weight
losses following bariatric surgery. The interpretation of this counterintuitive finding is
that the self-regulation skills that help patients maintain their sobriety also help patients
adhere to the demands of the recommended postoperative diet.
Disinhibition and Impulsivity following Bariatric Surgery Encouragingly, studies have shown
that there are improvements in executive functioning in persons with extreme obesity in the
first two years after bariatric surgery. Postoperatively, patients typically report decreases
in disinhibition and hunger, as well as increases in cognitive restraint. The physical
aspects of bariatric surgery typically prevent individuals from eating the objectively large
amount of food necessary to meet the diagnostic criteria of BED. However, many individuals
continue to report the feeling of loss of control over their eating.The self-reported
inability to control these impulses postoperatively is associated with smaller weight losses
and greater emotional distress in the first few postoperative years. There is additional
evidence that patients have difficulty with impulse control after surgery. A number of studies
have suggested that there is an increased risk of substance abuse following bariatric
surgery. King and colleagues, in their seminal investigation, found an increased rate of
alcohol use disorder in the second postoperative year as compared to the year prior to
surgery or in the first postoperative year. Other recent studies also have found increases in
alcohol or composite substance abuse (drug, alcohol, or cigarettes) in the first two years
after bariatric surgery. Postoperative substance use has been associated with smaller
postoperative weight losses, postoperative nocturnal eating, and subjective hunger. Patients
at greatest risk for new onset SUDs were more likely to report problems with high sugar/low
fat food before surgery, further suggesting the role of impulsivity in eating behavior and
substance use before and after surgery. This increase in substance abuse after surgery has
been described as addiction transfer and characterized as a modern example of symptom
substitution in which abuse of one substance (food) is replaced by another (alcohol or drugs)
when patients are unable to consume large amounts of food after surgery. A potential
contributor to addiction transfer may be emotional dysregulation. In general, symptoms of
depression typically improve within the first six months of bariatric surgery as patients are
in the period of most rapid weight loss. Within the first two postoperative years, the use of
anti-depressant medications also decreases; however, a substantial minority of patients
report using these medications two years after surgery. As most patients begin to regain
weight postoperatively, they also experience an erosion of the improvements in depressive
symptoms and quality of life. In addition, a higher-than-expected number of postoperative
suicides have been documented. A secondary aim of the proposed study will investigate the
relationship between changes in weight during the first two postoperative years and changes in
psychosocial status.
The proposed observational study will evaluate the relationship between measures of
psychopathology, disordered eating, and impulsivity, (each assessed preoperatively and in the
early postoperative period) and changes in weight and psychosocial status in the first two
years after bariatric surgery. All participants will complete assessments at baseline (before
surgery) and at 6, 12, and 24 months follow-up.
