title: Impact of Pill Burden on Adherence, Risk of Hospitalization, and Viral Suppression in Patients with HIV Infection and AIDS Receiving Antiretroviral Therapy.
abstract: OBJECTIVE
  To evaluate the impact of pill burden on outcomes in patients with human immunodeficiency virus (HIV) infection and acquired immune deficiency syndrome (AIDS) receiving antiretroviral therapy (ART) as a single-tablet regimen (STR) or multiple-tablet regimen (MTR).
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  South Carolina Medicaid medical and pharmacy paid claims data were obtained from the South Carolina Revenue and Fiscal Affairs Office; laboratory data were obtained from the South Carolina Department of Health and Environmental Control.
  
  
  METHODS
  A total of 2174 patients covered by South Carolina Medicaid who were dispensed a complete ART STR (580 patients) or MTR (1594 patients) lasting at least 60 days between January 1, 2006, and December 31, 2013.
  
  
  RESULTS
  Outcomes were ART adherence; risk of, time to, and total number of hospitalizations; and viral load suppression. Patients were followed from the index date (start date of their complete ART regimen) until the earliest date of one of the following: treatment discontinuation; treatment switch from MTR to STR, or vice versa; end of study period; last date of Medicaid eligibility; or death. Differences in outcomes were evaluated by using bivariate χ(2) and Wilcoxon rank sum tests, as well as multivariate regression models controlling for covariates measured during a 6-month baseline period. The STR and MTR cohorts were, on average, similar in terms of age at index date, Charlson Comorbidity Index score, sex, drug abuse, and mental health diagnoses, but they differed significantly in racial composition, index year of regimen, previous treatment, baseline viral load, and CD4 measures. The bivariate analysis revealed that the STR cohort was more adherent (p<0.0001), had a lower risk of hospitalization (p=0.0076), and had a higher proportion of patients with viral suppression (64.5% vs 49.5%, p<0.0001). In addition, multivariate regression models revealed that the STR cohort was more adherent and was associated with a lower risk of hospitalization (hazard ratio 0.71, 95% confidence interval 0.59-0.86), but no significant difference in viral load suppression was noted between the STR and MTR cohorts.
  
  
  CONCLUSIONS
  The STR was associated with higher adherence rates and a lower risk of hospitalization (both in the adjusted and unadjusted analyses) in South Carolina Medicaid patients with HIV infection and AIDS. A higher proportion of patients in the STR cohort had viral suppression during the follow-up period in the unadjusted analysis compared with the MTR cohort; however, no significant difference in viral suppression was observed when controlling for adherence.
authors.affiliation: Department of Clinical Pharmacy and Outcomes Sciences, University of South Carolina, South Carolina College of Pharmacy, Columbia, South Carolina.
authors.forename: S
authors.initials: S
authors.lastname: Scott Sutton
authors.affiliation: Health and Demographics, South Carolina Revenue and Fiscal Affairs Office, Columbia, South Carolina.
authors.forename: Joseph
authors.initials: J
authors.lastname: Magagnoli
authors.affiliation: Department of Epidemiology & Biostatistics, University of South Carolina, Columbia, South Carolina.
authors.forename: James W
authors.initials: JW
authors.lastname: Hardin
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy* / Q000628:therapy / Q000821:virology; D000328:Adult; D044966:Anti-Retroviral Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active / Q000009:adverse effects; D015331:Cohort Studies; D003131:Combined Modality Therapy / Q000009:adverse effects; D017281:Cost of Illness; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000188:drug therapy* / Q000628:therapy / Q000821:virology; D006760:Hospitalization; D006801:Humans; D008297:Male; D008484:Medicaid; D055118:Medication Adherence; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D013022:South Carolina; D000072230:Sustained Virologic Response; D013607:Tablets; D014481:United States
chemical_list: D044966:Anti-Retroviral Agents; D013607:Tablets
keywords: HIV; MTR; STR; adherence; hospitalization; multiple-tablet regimen; pill burden; single-tablet regimen