Observational Comparative Effectiveness of Pharmaceutical Treatments for Obesity within the Veterans Health Administration.

STUDY OBJECTIVE

To compare the effectiveness of weight-management medications used to assist with weight loss in real-world clinical practice in the Veterans Health Administration (VHA).

DESIGN

Retrospective, multicenter, observational cohort study.

DATA SOURCE

National VA Corporate Data Warehouse.

PATIENTS

A total of 66,035 VA patients aged 18 years or older with a body mass index of 25 kg/m or greater who had an initial fill for a study medication (orlistat [6153 patients], phentermine [304 patients], lorcaserin [298 patients], or phentermine-topiramate extended release [233 patients]) or participation in the VA's MOVE! weight-management program with at least three total visits in a clinic coded as a MOVE clinic in the subsequent 24 weeks (59,047 patients) between January 1, 2012, and July 1, 2016.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was the percentage change in weight from baseline to at least 20 weeks or later (i.e., closest weight to 6 months). Secondary outcomes were difference in the percentage of weight loss at 12 and 36 weeks; changes in blood pressure, hemoglobin A , high-density and low-density lipoprotein cholesterol and triglyceride levels; and percentage of patients who achieved at least a 5% and 10% weight loss at 6 months from baseline in each group after at least 20 weeks. For the primary outcome, the percentage decrease in weight from baseline after at least 20 weeks in the lorcaserin, phentermine-topiramate, phentermine, orlistat, and MOVE! groups were 3.6%, 4.1%, 3.6%, 2.1%, and 1.6%, respectively (phentermine-topiramate group vs. MOVE! group, p<0.05). Achievement of at least a 5% weight loss after at least 20 weeks differed significantly among groups, ranging from 26.2% for the MOVE! Program only group to 40.3% for patients in the phentermine-topiramate group.

CONCLUSION

In the VA population, the effectiveness of four available weight-management medications was similar. Patients receiving phentermine-topiramate had a greater proportion of weight loss after at least 20 weeks compared with those solely enrolled in the VA's MOVE! weight-management program.