Assessment of Glycemic Control at St. Luke’s Free Medical Clinic: Retrospective Chart Review (Preprint)

Abstract

A free clinic is a health care delivery model that provides primary care and pharmaceutical services exclusively to uninsured patients. With a multidisciplinary volunteer clinical staff, which includes physicians, social workers, dieticians, and osteopathic medical students, St. Luke’s Free Medical Clinic (SLFMC) cares for over 1700 patients annually in Spartanburg, South Carolina.

This study aims to measure the change, over time, in patient hemoglobin A_1c measurements at the SLFMC to quantify the success of the clinic’s diabetes treatment program.

A prospective-retrospective chart review of patients (n=140) enrolled at the SLFMC between January 1, 2018, and January 1, 2021, was performed. Patients were stratified as having controlled (hemoglobin A_1c<7.0, n=53) or uncontrolled (hemoglobin A_1c≥7.0, n=87) diabetes relative to a therapeutic hemoglobin A_1c target of 7.0, which is recommended by the American Diabetes Association. For both controlled and uncontrolled groups, baseline hemoglobin A_1c values were compared to subsequent readings using a Wilcoxon matched-pairs signed rank test. Results from the SLFMC population were compared to the published literature on hemoglobin A_1c from other free clinics.

Patients with uncontrolled diabetes experienced significant reductions in median hemoglobin A_1c at both 6 months (<i>P</i>=.006) and 1 year (<i>P</i>=.002) from baseline. Patients with controlled diabetes showed no significant changes. Black and Hispanic patients with uncontrolled diabetes experienced a 1.0% mean improvement in hemoglobin A_1c over the study window. The SLFMC’s wholly uninsured patient population showed a population rate of controlled diabetes (42%), which was similar to recent nationwide averages for adults with diabetes (51% to 56%), as reported by the National Health and Nutrition Examination Survey. The clinic’s Hispanic population (n=47) showed the greatest average improvement in hemoglobin A_1c of any ethnic group from baseline. Additionally, 61% of the SLFMC’s Black population (n=33) achieved a hemoglobin A_1c of <7.0 by the end of the study window, which surpassed the nationwide averages for glycemic control.

We present free clinic hemoglobin A_1c outcomes obtained through a retrospective chart review. Uninsured patients treated for diabetes at the SLFMC show a reduction in hemoglobin A_1c, which is comparable to nationwide standards, although average hemoglobin A_1c levels in this study were higher than nationwide averages. Black and Hispanic patients with uncontrolled diabetes showed a mean 1% improvement in hemoglobin A_1c levels. These results represent some of the first in the literature emerging from a free clinic that is not affiliated with a major medical school.