title: The impact of persistence with therapy on inpatient admissions and emergency room visits in the US among patients with multiple sclerosis.
abstract: OBJECTIVE
  Disease-modifying therapy (DMT) for multiple sclerosis (MS) can reduce relapses and delay progression; however, poor adherence and persistence with DMT can result in sub-optimal outcomes. The associations between DMT adherence and persistence and inpatient admissions and emergency room (ER) visits were investigated.
  
  
  METHODS
  Patients with MS who initiated a DMT in a US administrative claims database were followed for 1 year. Persistence to initiated DMT was measured as the time from DMT initiation to discontinuation (a gap of >60 days without drug 'on hand') or end of 1-year follow-up. Adherence to initiated DMT was measured during the persistent period and was operationalized as the medication possession ratio (MPR). Patients with an MPR <0.80 were considered non-adherent. Claims during the 1-year follow-up period were evaluated for the presence of an all-cause inpatient admission or an ER visit. Adjusted odds ratios (AORs) for inpatient admission or ER visit comparing persistent vs non-persistent and adherent vs non-adherent patients were estimated using logistic regression models adjusted for patient characteristics.
  
  
  RESULTS
  The final sample included 16,218 patients. During the 1-year follow-up period, 35.3% of patients discontinued their initiated DMT and 13.9% were not adherent while on therapy. During that same period, 10.0% of patients had an inpatient admission and 24.9% had an ER visit. The likelihoods of inpatient admission and ER visit were significantly decreased in persistent patients (AOR [95% CI] = 0.50 [0.45, 0.56] and 0.65 [0.60, 0.69], respectively) and in adherent patients (AOR [95% CI] = 0.83 [0.71, 0.97] and 0.86 [0.77, 0.95], respectively).
  
  
  CONCLUSIONS
  Persistence and adherence with initiated DMT are associated with decreased likelihoods of inpatient admission or ER visit, which may translate to improved clinical outcomes.
authors.affiliation: a a Genentech, Inc., Health Economics , South San Francisco , CA , USA.
authors.forename: Nina Parikh
authors.initials: NP
authors.lastname: Thomas
authors.affiliation: b b Truven Health Analytics, Health Economics , Ann Arbor , MI , USA.
authors.forename: Suellen
authors.initials: S
authors.lastname: Curkendall
authors.affiliation: b b Truven Health Analytics, Health Economics , Ann Arbor , MI , USA.
authors.forename: Amanda M
authors.initials: AM
authors.lastname: Farr
authors.affiliation: a a Genentech, Inc., Health Economics , South San Francisco , CA , USA.
authors.forename: Elaine
authors.initials: E
authors.lastname: Yu
authors.affiliation: a a Genentech, Inc., Health Economics , South San Francisco , CA , USA.
authors.forename: Dana
authors.initials: D
authors.lastname: Hurley
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D007345:Insurance Claim Review; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000188:drug therapy*; D010343:Patient Admission / Q000706:statistics & numerical data*; D012008:Recurrence; D012189:Retrospective Studies; D055815:Young Adult; D016903:Drug Monitoring
chemical_list: D007166:Immunosuppressive Agents
keywords: Disease-modifying therapy; Hospitalization; Multiple sclerosis; Relapse rate; Therapy adherence; Therapy persistence