title: Cost and consequences of noncompliance with osteoporosis treatment among women initiating therapy.
abstract: OBJECTIVE
  The objective was to evaluate compliance with osteoporosis (OP) treatments and determine the fracture and healthcare burden associated with noncompliance.
  
  
  METHODS
  This retrospective analysis of a US claims database identified women initiating an OP medication from 1 January 2002 to 30 June 2009. Patients were ≥55 years and had ≥1 pharmacy claim for a bisphosphonate or non-bisphosphonate (raloxifene, calcitonin, teriparatide); the index date was the first pharmacy claim. There were three study periods: baseline (12 months pre-index); compliance period (0-12 months post-index); and follow-up period (12-24 months post-index). Medication possession ratio (MPR) was calculated during the compliance period to differentiate two cohorts: compliant (MPR ≥ 80%) and noncompliant (MPR < 80%). Outcomes during follow-up were modeled by logistic regression (presence of fracture), Poisson regression (healthcare utilization incidence rate) and gamma regression (healthcare costs), all adjusted for patient demographic and clinical characteristics.
  
  
  RESULTS
  Overall, 685,505 women initiating OP therapy were identified and 57,913 (8.4%) met the inclusion criteria: only 23,430 (40.5%) were compliant and 34,483 (59.5%) were noncompliant. Mean age was 64 years. Noncompliance was associated with a 20% higher risk of any fracture (odds ratio: 1.20, 95% CI = 1.07-1.35), a higher incidence rate ratio (IRR) for inpatient utilization (IRR: 1.26, 95% CI = 1.19-1.34) and a lower rate of outpatient utilization (IRR: 0.97, 95% CI = 0.95-0.98). Noncompliant patients had 13% higher medical costs (cost ratio: 1.13, 95% CI = 1.06-1.21) than compliant patients.
  
  
  CONCLUSIONS
  Inclusion in this study required 36 months of continuous healthcare coverage. Thus, the results are primarily applicable to a stable, managed care population and may not be generalizable to other populations.
  
  
  CONCLUSIONS
  Noncompliance with OP therapy was associated with a higher risk of fracture, higher all-cause medical costs and a higher frequency of inpatient service utilization. Additional research is needed to identify barriers to compliance with OP therapy.
authors: Merck & Co. Inc. , Lebanon, NJ , USA.
authors: Ankita
authors: A
authors: Modi
authors: Ethel S
authors: ES
authors: Siris
authors: Jackson
authors: J
authors: Tang
authors: Shuvayu
authors: S
authors: Sen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003695:Delivery of Health Care / Q000191:economics; D004164:Diphosphonates / Q000191:economics / Q000627:therapeutic use*; D005260:Female; D017048:Health Care Costs; D006801:Humans; D016015:Logistic Models; D008329:Managed Care Programs / Q000191:economics; D055118:Medication Adherence; D008875:Middle Aged; D010024:Osteoporosis / Q000188:drug therapy* / Q000191:economics; D058866:Osteoporotic Fractures / Q000191:economics / Q000453:epidemiology*; D012189:Retrospective Studies; D019379:Teriparatide / Q000191:economics / Q000627:therapeutic use
chemical_list: D004164:Diphosphonates; D019379:Teriparatide
keywords: Adherence; Compliance; Fracture risk; Healthcare costs; Healthcare utilization; Osteoporosis