Impact of US Medicare Coverage on Multimorbidity Accumulation Among Patients Seen in Community Health Centers

Context: Many studies show the negative impact of lacking health insurance and having coverage gaps on access to care and medication, and chronic disease management in the United States. Inadequately insured people are more likely to live in poverty and be from racial and ethnic minority groups. There is evidence, however, that gaining insurance is associated with receipt of preventive services, smoking cessation, improved health and survival, and diagnosis of previously undetected conditions. No previous study has assessed the impact of insurance coverage patterns on the multimorbidity burden among patients receiving care in community health centers (CHCs).

Objective: To assess the change in chronic disease levels pre- and post-Medicare age eligibility (65 years) among patients with different longitudinal insurance patterns.

Study Design: Retrospective observational cohort study.

Setting or Dataset: Electronic health record data from 989 CHCs in the Accelerating Data Value Across a National Community Health Center Network (ADVANCE) clinical research network.

Population Studied: Adults aged 62-68 years old (N=45,527) with ≥1 ambulatory care visit both pre- and post-Medicare eligibility and ≥1 documented chronic disease in 2014-2019.

Outcome Measures: Chronic disease indicators for 20 chronic diseases in the Health and Human Services Multiple Chronic Conditions (HHS MCC-20) framework.

Results: Pre-Medicare age, 76% of patients had continuous insurance and an average of 2 chronic diseases. Post-Medicare, 86% of patients had continuous insurance. Using difference-in-differences GEE Poisson regression, adjusted for patient sex, race/ethnicity, and federal poverty level, those gaining insurance via Medicare showed significantly greater accumulation of chronic disease than those continuously insured (RR=1.06, 95%CI=1.05-1.07), while those losing insurance had significantly less accumulation of chronic disease (RR=0.96, 95%CI=0.95-0.98).

Conclusions: Nearly one quarter of older patients with at least one chronic health problem in CHCs do not have continuous health insurance. Most have two or more conditions needing continuous chronic care management. The greater increase in the chronic disease accumulation among those who gain Medicare suggests that continuity of care may facilitate diagnosis and management of undetected health conditions. CHCs continue to be essential care providers for aging vulnerable adults with inadequate or absent health care coverage.