Subject(s)
Databases, Factual , Pharmacoepidemiology/organization & administration , Research/organization & administration , History, 20th Century , History, 21st Century , Humans , Medical Record Linkage , Pharmacoepidemiology/history , Prescription Drugs/therapeutic use , Research/history , SaskatchewanABSTRACT
PURPOSE: To estimate the risk (and determinants) of discontinuing cholinesterase inhibitors (ChEIs) in a population-based sample of Alzheimer's disease (AD) patients. METHODS: This is a retrospective cohort study based on linked de-identified administrative health data from the province of Saskatchewan, Canada. The cohort included all AD patients receiving a ChEI prescription during the first year of provincial coverage (2000-2001). Persistence was defined as no gap of 60+ days between depletion and subsequent refill of a ChEI prescription. Kaplan-Meier analysis was used to estimate the risk of discontinuation over 40 months. Cox regression with time-varying covariates was used to assess risk factors for ChEI discontinuation. RESULTS: The sample included 1080 patients (64% female, average age 80 +/- 7 years). Baseline mean (SD) Mini-Mental State Examination (MMSE) and Functional Activities Questionnaire (FAQ) scores were 20.8 (4.4) and 17.5 (7.7), respectively. Over 40 months, 84% discontinued therapy. The 1-year risk of discontinuation was 66.4% (95%CI 63.5-69.3%). Discontinuation was significantly more likely for females (adjusted HR 1.34, 95%CI 1.16-1.55) and among those with lower MMSE scores (2.52, 2.01-3.17 if <15), not receiving social assistance (1.25, 1.07-1.45), and paying at least 65% of total prescription costs (1.51, 1.30-1.74). It was significantly less likely for patients with frequent physician visits (0.78, 0.66-0.93, for 7-19 vs. <7 visits), higher Chronic Disease Scores (0.74, 0.61-0.89, for 7+ vs. <4), and FAQ scores of 9+ (0.82, 0.69-0.99). CONCLUSION: The likelihood of discontinuing ChEI therapy was high in this real-world sample of AD patients. Significant predictors included clinical, socioeconomic, and practice factors.
Subject(s)
Alzheimer Disease/drug therapy , Cholinesterase Inhibitors/therapeutic use , Aged , Aged, 80 and over , Cholinesterase Inhibitors/administration & dosage , Cohort Studies , Female , Humans , Kaplan-Meier Estimate , Male , Neuropsychological Tests , Proportional Hazards Models , Retrospective Studies , Risk Factors , Saskatchewan , Sex Factors , Socioeconomic Factors , Time FactorsABSTRACT
The study objective was to investigate a possible association between statin use and breast cancer (BRCA). An historical cohort design based on Saskatchewan's population health services databases was used. All eligible women with > or = 1 statin prescription from 1989 to mid-1997 and an age-sex-matched nonexposed group were followed up to 8.5 years (mean 4.2 years). Relative rates (RR) of BRCA were estimated and stratified by age, statin exposure time, and prior hormone use. Thirteen thousand five hundred ninety-two statin users and 53,880 nonexposed subjects were identified. Eight hundred seventy-nine incident BRCA cases were identified. Statins were not associated with BRCA risk in women < or = 55 years. Among subjects >55 years, the RR for BRCA was 1.15 (0.97, 1.37). Stratified analyses revealed increases in risk in short-term statin users and statin users with long-term hormone replacement therapy (HRT) exposure. More studies are needed to determine if short-term statin use and statin use with long-term HRT exposure increases postmenopausal BRCA risk. Published by Elsevier Science Inc.