WEDNESDAY, July 15, 2026 (HealthDay News) -- Bariatric surgery may increase the risk for alcohol problems, according to two studies published online June 17 in the International Journal of Obesity.
Magnus Strømmen, R.N., Ph.D., from Trondheim University Hospital in Norway, and colleagues conducted a retrospective, population-based cohort study involving 12,244 patients who underwent Roux-en Y gastric bypass (RYGB) and 5,556 who underwent sleeve gastrectomy (SG) between 2008 and 2018. The researchers found that 3.2 percent of patients had developed a new alcohol-related diagnosis by Dec. 31, 2018, an incidence rate of 6.34 per 1,000 person-years. For these diagnoses, the adjusted hazard ratio was 1.69 for those undergoing RYGB versus SG. Patients with versus without alcohol-related diagnoses had an adjusted hazard ratio of 2.08 for death.
In a second study, Strømmen and colleagues conducted a prospective study including 33 adults (14 with RYGB; 19 with SG) without histories of alcohol use disorder to compare ethanol pharmacokinetics before and after surgery. Maximum plasma concentration (Cmax), time to reach maximum concentration (Tmax), and area under the curve to the last measurable concentration (AUClast) were included as primary outcomes. The researchers found that after both surgical procedures, the ethanol uptake was bioequivalent for AUClast, but not for Cmax and Tmax. RYGB gave a 27 percent higher Cmax and 31 percent shorter Tmax than SG at 12 months. Profound and persistent alterations in ethanol pharmacokinetics were induced by both procedures during the three-year period, with an approximate doubling of Cmax and AUClast and a reduction in Tmax to about half the preoperative value.
"Patients should be educated about the mechanisms behind increased risk after surgery, and not least how to react differently to alcohol intoxication after surgery as a result of the sudden increase," Strømmen said in a statement.
