title: Medication utilization and adherence in a health savings account-eligible plan.
abstract: OBJECTIVE
  To evaluate the impact of a consumerdirected health plan with a health savings account (CDHP-HSA) on utilization of and adherence to medications among individuals with chronic disease.
  
  
  METHODS
  Pre-post comparison study with matched control group (difference-in-differences analysis).
  
  
  METHODS
  Data on workers and dependents with 1 or more of 5 chronic conditions--hypertension, dyslipidemia, diabetes, asthma/chronic obstructive pulmonary disease (COPD), and depression--were obtained from an employer that fully replaced its preferred provider organizations (PPOs) with a CDHP-HSA in 2007. A control group of participants from an employer that maintained its PPO throughout the 3-year study period (2006-2008) was created by matching on preperiod (2006) individual characteristics. Difference-in-differences estimates of the impact of the CDHP-HSA were derived by chronic condition for number of prescriptions, proportion of days covered (PDC), and an indicator for a PDC of 0.80 or higher.
  
  
  RESULTS
  During the first year after implementation, enrollees with hypertension, dyslipidemia, and diabetes had significantly less medication utilization (by 1-2 prescriptions) and lower adherence rates (by 0.05-0.09 in PDC; 0.04-0.13 in the proportion adherent). These reductions abated, yet remained, after 2 years among hypertension and dyslipidemia patients. The PDC was significantly lower in patients with depression by 0.07 and 0.05 after 1 and 2 years under the new plan, respectively. No statistically significant impacts were detected on enrollees with asthma/COPD.
  
  
  CONCLUSIONS
  A CDHP-HSA full replacement was associated with reduced adherence for 4 of 5 conditions. If this reduced adherence is sustained, it could adversely impact productivity and medical costs.
authors: Health Research and Education Program, Employee Benefit Research Institute, 1100 13th St, NW, Ste 878, Washington, DC 20005. E-mail: Fronstin@ebri.org.
authors: Paul
authors: P
authors: Fronstin
authors: Martin-J
authors: MJ
authors: Sepulveda
authors: M Christopher
authors: MC
authors: Roebuck
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002908:Chronic Disease / Q000188:drug therapy*; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D005260:Female; D006264:Health Benefit Plans, Employee / Q000191:economics; D006801:Humans; D008297:Male; D020402:Medical Savings Accounts; D008875:Middle Aged; D014481:United States; D016903:Drug Monitoring