Characterizing Obesity in a Large Health Care Delivery System

Objectives:To characterize the prevalence of obesity and associated health care use within an integrated health care system in California.

Study Design:Cross-sectional study using electronic health records.

Methods:Primary care patients 18 years and older receiving care at Sutter Health between 2015 and 2020 were included in the study. Obesity was classified and health care utilization was ascertained at index and during the follow-up periods. Differences in prevalence by demographic and clinical characteristics among patients with and without obesity were assessed. Logistic regression was used to estimate the relationship between obesity class and health care utilization (outpatient encounters).

Results:Of the 1,094,790 primary care patients included in the analysis, 35% were classified as having obesity, defined as a body mass index of 30 kg/m2 or more or 25 kg/m2 or more for Asian individuals. Obesity prevalence was greater in Hispanic patients (46%) than in non-Hispanic White patients (30%). Patients without obesity had fewer outpatient visits (mean [SD], 3.7 [3.8]) than those with class 1 (4.1 [4.0]), class 2 (4.6 [4.4]), and class 3 (5.2 [4.8]) obesity. In the fully adjusted regression model, the odds of being a high utilizer among patients with obesity were 1.1 (class 1), 1.2 (class 2), and 1.3 (class 3) times that of patients without obesity (P < .001).

Conclusion:Obesity prevalence is high among patients in the Sutter Health system, varying by race/ethnicity, and was associated with increased outpatient visit utilization. There is a need for greater awareness of the impact of obesity and the specific patient populations affected by the disease.