July 21 (UPI) — A major study conducted by Swedish medical researchers on more than 4,000 patients with obesity has discovered that those who underwent weight loss surgery were 2.5 times more likely to develop a non alcohol-related substance use disorder compared to those who received standard obesity care.
The Swedish Obese Subjects prospective study, published in the journal Obesity on Friday, compared the outcomes of 2,010 patients who underwent appetite-suppressing bariatric surgeries (gastric bypass, vertical banded gastroplasty, or gastric banding) with a matched control group of 2,037 subjects.
The study, known as the SOS study, aimed to investigate the evidence linking weight loss surgery to prescription and illicit drug misuse. It involved 25 Swedish public surgical departments and 480 primary health care centers, and followed the two groups over a span of 24 years.
Lead author Professor Per-Arne Svensson of Gothenburg University’s Department of Molecular and Clinical Medicine stated, “The current study shows that non-alcohol substance use disorder was 2.5 times more common after gastric bypass surgery compared with controls receiving usual obesity care, but the total number of patients having non-alcohol substance use disorder was overall low. Healthcare professionals should consider the risk of non-alcohol substance use disorder in the care of patients treated with gastric bypass surgery.”
The authors acknowledged certain limitations of the study, including the fact that the surgeries were performed between 1987 and 2001, making them less common in today’s medical landscape. Additionally, the surgery cohort was at higher risk than the control group due to factors such as age, weight, smoking history, and education level.
The control group consisted of fewer men, and the average Body Mass Index (BMI) was 40.1 kg/m2 for the control group compared to 43.8 kg/m2 for the surgery group.
Participants with certain conditions or histories, such as gastric or duodenal ulcers, previous bariatric surgery, recent heart attack or cancer, bulimia, psychiatric issues, or high drug/alcohol levels, were excluded from the study.
Follow-ups of patients in the three surgery groups revealed a significant reduction in BMI in the first year after surgery, followed by weight regain. However, after eight to ten years, the BMI stabilized. Meanwhile, changes in BMI among the control group during the follow-ups were minimal.
In a follow-up commentary, Professor James Mitchell from the University of North Dakota emphasized the need to consider both biological and psychosocial factors, as post-surgery medical comorbidities and lack of improvement in quality of life or physical mobility could be the mechanisms behind substance use disorders, rather than the surgery itself.
Mitchell concluded that candidates for bariatric surgery should be thoroughly informed about the risks and closely monitored for any developments. However, he expressed skepticism about the likelihood of this occurring due to the inadequate follow-up care that many of these patients receive.
