Impact of Primary Care Worksite Health and Wellness Clinics on HbA1c Level Among Prediabetic or Diabetic Employees

Purpose: To determine whether the use of worksite health and wellness clinics reduced hemoglobin A1c (HbA1c) for prediabetic and diabetic employees. Design: Hemoglobin A1c values were compared between clinic users and matched non-users. Setting: The Wonderful Company's (TWC's) agricultural and packaging sites in Central California. Sample: TWC's 2016 to 2017 employees who used clinics (n = 445, defined below) and clinic non-users (n = 217) who had HbA1c screening and worked at TWC for 3 or more months each year. Intervention: A unique worksite health and wellness clinic that offers multidisciplinary primary medical care in synergy with TWC's overall wellness programs. Measures: Exposure was clinic use, defined by frequency and patterns of visits. Hemoglobin A1c was the outcome of interest. Analysis: Users and non-users were propensity score matched using the 2016 employee data including HbA1c, and then 2017 HbA1c values were compared between the 2 groups. Results: The 2017 HbA1c of diabetic employees was lower among clinic users compared to non-users (7.42 vs 8.53, P < .001). Differences in HbA1c among prediabetics or diabetics and prediabetics aggregated were not statistically significant, despite TWC's population-level data showing a reduction in prediabetes prevalence. The clinic impact results were robust to multivariate analyses and an alternative definition of utilization. Conclusion: The implementation of TWC's Health and Wellness clinics was associated with reductions in HbA1c among diabetics, but further research is needed on prediabetics.