Utilization and Cost Analysis of a Chronically Ill, Newly Insured Indigent Population.

The Affordable Care Act expanded health insurance for low-income, uninsured individuals. Few longitudinal analyses have investigated how insurance expansion influences cost and utilization among adults with chronic conditions. This study conducted longitudinal analysis investigating time trends in utilization and cost among newly insured, chronically ill, low-income individuals using Generalized Estimating Equations models. For hospitalization, hospital outpatient services, emergency department (ED) visits, and primary care visits, two indicators were measured: the proportion of enrollees with services and the average number of visits among users. The average health expenditure per person was estimated using a gamma distribution. Results indicate that the number of individuals using inpatient or ED services was highest during the first six months following insurance coverage and decreased in subsequent periods, while primary care visits increased during the first year. Using six-month rather than annual measures of utilization and cost may be necessary to identify short-run changes following initial insurance coverage.