Evaluation of Pharmacologic Interventions for Weight Management in a Veteran Population
Background: Veterans are disproportionately impacted by weight-related morbidity: 40% of veterans are categorized as obese and an additional 38.5% are overweight. Medications are recommended as an adjunct to lifestyle and dietary changes. Guidelines recommend 7 weight management medications, including orlistat, liraglutide, phentermine, phentermine/topiramate, lorcaserin, and naltrexone/bupropion.
Methods: A single-center, retrospective chart review was conducted for patients who started weight management medications at Veteran Health Indiana in Indianapolis. The primary outcomes included total weight loss and weight loss as a percentage of baseline weight at 3, 6, 12, and > 12 months of therapy. Secondary outcomes included weight loss of 5% from baseline, rate of successful weight maintenance after initial weight loss of 5% from baseline, adverse drug reaction monitoring, and use of weight management medications across clinics at this site.
Results: The absolute weight difference over 12 months of weight management medication therapy was 15.8 kg. At each time point, weight loss was found to be statistically significant when compared with baseline ( P < .001). Average weight change was greatest with orlistat (−25.9 kg) and naltrexone/bupropion was associated with a gain of 2.1 kg over the duration of the study. A majority of the patients analyzed lost the guideline-recommended 5 to 10% from baseline while taking weight management medication.
Conclusions: Weight management medications in a veteran population produced initial weight loss consistent with previous studies. However, there is room for improvement in follow-up strategies to promote greater weight maintenance after initial weight loss. Considering the high health care costs, personal burden, and potential long-term complications associated with obesity, efforts to promote continued development of programs that support weight management and maintenance are imperative.
Comorbidities and Medication Use
Hypertension (66%), hyperlipidemia (64%), and psychiatric diagnoses (50%) were most common comorbid conditions. Substance use (23%) and T2DM (40%) were the most common comorbidities influencing medication choice. Substance use evaluation included amphetamines and cocaine for this analysis.
Phentermine/topiramate is the preferred first-line agent unless patients have contraindications for use, in which case naltrexone/bupropion is recommended, based on guidelines for weight management medications within the VHI system. However, for patients with comorbid T2DM, liraglutide is preferred because of its beneficial effects for both weight loss and blood glucose control.2 Most patients at VHI were started on liraglutide (44%) or phentermine/topiramate (42%), which was in line with recommendations. Our sample included ≥ 1 prescription for each medication available at our facility, although the number of patients on each medication was not equal. Of note, the one patient taking lorcaserin at the time of study discontinued therapy in response to recent FDA guidance.9
Medications for comorbid conditions could contribute to weight gain. Of the patient sample, β blockers (n = 24) and anticonvulsants, including gabapentin and pregabalin (n = 22) were the most common Other medications that could have contributed to weight gain included sulfonylureas (n = 5), antipsychotics (n = 4), tricyclic antidepressants (n = 2), and hormone replacement therapies (n = 2).
Primary Outcomes
The mean weight of participants dropped from 129.9 to 114.2 kg over the 12 months of weight management medication therapy for a absolute difference of 15.8 kg (Figure 1 and eTable 1 available at doi:10.12788/fp.0117). Weight loss was recorded at 3, 6, 12, and > 12 months of weight management therapy. At each time point, weight loss was statistically significant (P < .001) compared with baseline (Table 2), even though not every patient had weight loss records at each time point.
When classified by medication choice,
Secondary Outcomes
More than one-half of the patients analyzed lost 5 to 10% from baseline while taking weight management medication.
Among patients who lost at least 5% from baseline, we performed further analysis to assess weight maintenance of 3 to 5% from baseline for 12 months.
We found that most of our prescriptions (n = 50) were entered by the endocrinology department in conjunction with the MOVE! program (eTable 3 available at doi:10.12788/fp.0117). All 4 of our primary care clinics prescribed weight loss medication; however, 1 clinic prescribed the most. Other prescriptions came from community-based outpatient clinics or other specialties, including gastroenterology, orthopedics, and sleep medicine.
Nineteen (18%) patients experienced an adverse event (AE) that led to medication discontinuation, which was recorded in their chart (eTable 4 available at doi:10.12788/fp.0117). Most common AEs were GI upset with liraglutide or orlistat or dull aching and pain with phentermine/topiramate. Two severe AEs occurred: One patient experienced a change in mental health status and suicide attempt with naltrexone/bupropion; and 1 patient discontinued phentermine/topiramate because of a change in neurologic status.
Primarily medications were stopped because of inadequate weight loss (n = 13), and most patients tried additional medications. However, 1 medication failure resulted in sleeve gastrectomy. Other reasons for medication discontinuation included missed MOVE! appointments, patient lost to follow-up, and patient-elected discontinuation.
