title: Loss of health insurance among non-elderly adults in Medicaid.
abstract: BACKGROUND
  Major policy efforts to expand health coverage to the uninsured are under consideration. Drop-out among children in Medicaid--due to annual renewal requirements--is well-documented, but the recent extent of this problem among non-elderly adults is unknown.
  
  
  OBJECTIVE
  To estimate the loss of health insurance over time among adults in Medicaid and identify risk factors for drop-out.
  
  
  METHODS
  Survival analysis of Medicaid enrollment, using Kaplan-Meier curves and Cox proportional-hazards regression. Data are from the nationally representative Medical Expenditure Panel Survey, 2000-2004. The sample consists of non-elderly adults (n = 4,992) and children (n = 8,559) in Medicaid. Insurance status after 12 months was measured for all individuals enrolled in Medicaid at the survey's outset. A survival analysis of disenrollment was then conducted for newly enrolled individuals.
  
  
  RESULTS
  Nationwide, 2 million adults leave Medicaid and become uninsured annually. Disenrollment was significantly higher among adults than children (hazard ratio 1.75, 95% CI 1.65-1.86). Respectively, 20%, 43%, and 55% of adults disenrolled within 6, 12, and 23 months of initial enrollment. Lost eligibility explained a small portion of disenrollment. Six months after disenrolling, 17% had reenrolled in Medicaid, 34% had other insurance, and 49% were uninsured. Men, younger adults, and Hispanics were more likely to drop out; those in Medicaid managed care or with disabilities were less likely. Overall health status and diseases, such as diabetes, heart disease, and depression, had no effect on drop-out.
  
  
  CONCLUSIONS
  Drop-out from Medicaid is a major problem among adults--even among those with chronic diseases--and contributes to the presence of millions of uninsured Americans. Policy efforts to expand health coverage must address poor Medicaid retention. Clinicians should be aware of this issue when caring for non-elderly adults in Medicaid.
authors.affiliation: Division of General Medicine and Primary Care, Brigham and Women's Hospital, Boston, MA 02115, USA. bsommers@post.harvard.edu
authors.forename: Benjamin D
authors.initials: BD
authors.lastname: Sommers
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D003625:Data Collection / Q000379:methods / Q000639:trends; D005260:Female; D006801:Humans; D019458:Insurance Coverage / Q000191:economics / Q000639:trends; D007348:Insurance, Health / Q000191:economics / Q000639:trends; D008297:Male; D008484:Medicaid / Q000191:economics / Q000639:trends*; D017057:Medically Uninsured; D008875:Middle Aged; D012307:Risk Factors; D012959:Socioeconomic Factors; D014481:United States; D055815:Young Adult