Introduction: Though the prevalence of obesity is rising, little data exists on the real-world management of obese patients.
Methods: Adults in the Duke Primary Care system who had at least 2 body-mass index (BMI) measurements between 2013 and 2016 were included in this retrospective analysis. Patients were categorized according to baseline BMI: normal/underweight (BMI<25 kg/m2), overweight (BMI 25-29.9 kg/m2), obese I (BMI 30-34.9 kg/m2), obese II (BMI 35-39.9 kg/m2), obese III (BMI≥40 kg/m2). Baseline characteristics and weight loss medication use were assessed by BMI category. Change in BMI was modeled using a mixed model with random intercepts to capture patient-level variation and natural splines to capture non-linearities.
Results: Among 173,462 patients in our cohort, the majority were overweight (32%) or obese (overall 39%; obese I 21%, obese II 10%, obese III 8%). Obese patients were more likely than normal weight patients to be non-white, hypertensive, hyperlipidemic, diabetic, and with history of coronary artery disease or heart failure (p <.0001). Among obese patients, 9% were on metformin, less than 1% were on liraglutide or exenatide, and none were on the weight loss medications lorcaserin, pramlintide, phenteramine-topiramate, or bupropion-topiramate. Median (IQR) number of BMI evaluations/patient during 2 years of follow up was 5 (3, 11). BMI was generally unchanged over 2 years across all baseline BMI categories (figure). At two years, 15.8% of baseline obese III patients moved to the obese II category, but 15.2% of baseline obese II patients increased to the obese III category.
Conclusions: Even in a large, academic health care setting, prevalence of overweight and obesity is high, and pharmacologic therapy is under-utilized. Success with weight loss is limited, as most obese patients do not change weight categories over 2 years of follow-up. These data highlight opportunities for significant improvement in obesity care at a health system level.