The Effect on Medical Care Utilization of Extending Public Insurance to Low-Income Adults without Dependent Children

Thomas DeLeire, University of Wisconsin-Madison
Lindsey Leininger, University of Illinois at Chicago
Kristen Voskuil, University of Wisconsin-Madison
Donna Friedsam, University of Wisconsin-Madison

States’ decisions to expand Medicaid to low-income childless adults will depend, in part, on how this coverage may affect the use of medical care. In 2009, Wisconsin created a new public insurance program for low-income uninsured childless adults. We analyze administrative claims data spanning 2008 and 2009 on a population of 9,619 very low-income individuals who were automatically enrolled into this program in January 2009 using a case-crossover study design. In the 12 months following enrollment into public insurance, outpatient visits increased 29% and ED visits increased 46%. Inpatient hospitalizations declined 59% as did measures of preventable hospitalization. As other states expand coverage to childless adults, achieving these benefits while avoiding increasing emergency department utilization and its associated inefficiencies will depend on there being sufficient access to primary care.