Benefits of Bariatric Surgery for Patients with Type 2 Diabetes

Managing obesity and type 2 diabetes puts a strain on the healthcare system. According to researchers, treatments for obesity focusing on dietary, pharmaceutical, and behavior modifications are associated with high rates of failure, and medical management of diabetes is difficult. The American Diabetes Association has recommended that patients with diabetes reach a hemoglobin A1c level of <7%; however, fewer than half of all patients achieve that goal. In the past 5 years, use of bariatric surgery as an intervention in obesity has increased 200%. Studies have shown that the surgery results in long-term weight loss, improved lifestyle, and decreased mortality, but studies of the effect of the intervention on type 2 diabetes and healthcare costs are limited. Researchers recently conducted a retrospective time-series study to determine the impact of bariatric surgery on the use of diabetes medication and on total healthcare costs. They reported results of the study in Archives of Surgery [2010;145(8):726-731]. The study analyzed data on 2235 patients with diabetes in 7 Blue Cross Blue Shield healthcare plans who underwent bariatric surgery in the United States between January 1, 2002, and December 31, 2005. The 7 states were in the Blue Cross Blue Shield Obesity Care Collaborative. The primary outcome measures were overall healthcare costs and use of medications for diabetes. Administrative claims were used to measure the use of diabetes medications at specified time intervals prior to and following surgery as well as total medical healthcare costs per year. Costs included hospitalizations, procedures, medications, outpatient visits, consultations, and other payments made by the insurer. Diabetes medications were classified as insulin, sulfonylureas, metformin, alpha-glucosidase inhibitors, thiazolidinediones, or meglitinides. Among the study population, mean length of enrollment in the same Blue Cross Blue Shield plan was 2.1 years per person; a total of 5566 person-years were observed in the analysis. Mean age of the patients was 48.4 years and 74.5% were women. Of the 2235 study participants, 85.8% (n=1918) were taking at least 1diabetes medication 3 months prior to surgery; mean number of diabetes medications per patient was 4.4. At 6 months, 1 year, and 2 years after surgery, use of any diabetes medication had decreased to 25.3% (n=566 of 2235), 19.4% (n=358 of 1847), and 15.5% (n=166 of 1072), respectively. Follow-up data on 288 patients revealed that 3 years following surgery only 13.9% were using a diabetes medication. Insulin use among the 2235 patients in the study population at 3 months prior to surgery was 24.6% (n=550 of 2235 patients); at 1 year after surgery, insulin use was 5.5% (n=101 of 1847 patients). The researchers reported similar decreases for the 6 classes of diabetes medications. The greatest decrease was in metformin use: 52.9% (1182 of 2235) 3 months prior to surgery compared with 8.4% (156 of 1847) 1 year following surgery. In 74.7% of patients (n=1669 of 2235), bariatric surgery was associated with complete elimination of diabetes medications at 6 months after surgery, 80.6% (1489 of 1847) at 1 year, and 84.5% (n=906 of 1072) at 2 years after surgery. Younger age, male sex, and Roux-en-Y gastric bypass were all independently associated with cessation of use of diabetes medications. In-hospital mortality was 0.3% overall; 7.5% of the patients were readmitted to the hospital within 30 days of initial discharge, and 21.2% were readmitted within 1 year of initial discharge. Median cost for the surgery and initial hospitalization was $29,959. Compared with baseline annual cost of $6376 per person, total annual healthcare costs in the 3 years following surgery increased by $616 (9.7%) in the first year, but decreased by $2179 (34.2%) in year 2, and by $4498 (70.5%) in year 3. The researchers summarized that “bariatric surgery is associated with reductions in use of medication and in overall healthcare costs in patients with type 2 diabetes.” They concluded by stating that “health insurance should cover bariatric surgery because of its health and cost benefits.”—Tori Socha