title: Adherence with single-pill amlodipine/atorvastatin vs a two-pill regimen.
abstract: While clinical trials demonstrate the benefits of blood pressure and cholesterol reduction, medication adherence in clinical practice is problematic. We hypothesized that a single-pill would be superior to a 2-pill regimen for achieving adherence. In this retrospective, cohort study based on pharmacy claims data, patients newly initiated on a calcium channel blocker (CCB) or statin simultaneously or within 30 days, regardless of sequence, were followed (N=4703). Adherence was measured over 6 months as proportion of days covered (PDC). At baseline, mean age was 63.0 years, 51.6% were female, and mean number of other medications was 7.8. Overall, 16.9% of patients were on single-pill amlodipine/atorvastatin, 15.6% amlodipine + atorvastatin, 24.7% amlodipine + other statin, 13.9% other CCB + atorvastatin, 28.9% other CCB + other statin. Percentages of patients achieving adherence (PDC >or= 80%) were: 67.7% amlodipine/atorvastatin; 49.9% amlodipine + atorvastatin; 40.4% amlodipine + other statin; 46.9% other CCB + atorvastatin; 37.4% other CCB +other statin. After adjusting for treatment selection and cohort differences, odds ratios for adherence with amlodipine/atorvastatin were 1.95 (95% confidence interval [CI], 1.80-2.13) vs amlodipine + atorvastatin, 3.10 (95% CI, 2.85-3.38) vs amlodipine + other statin, 2.06 (95% CI, 1.89-2.24) vs other CCB + atorvastatin, 2.85 (95% CI, 2.61-3.10) vs other CCB + other statin (all p<0.0001). Single-pill amlodipine/atorvastatin may provide clinical benefits through improving adherence, offering clinicians a practical solution for cardiovascular risk management.
authors.affiliation: MedImpact Healthcare Systems, Inc. San Diego, CA, USA.
authors.forename: Bimal V
authors.initials: BV
authors.lastname: Patel
authors.forename: R Scott
authors.initials: RS
authors.lastname: Leslie
authors.forename: Patrick
authors.initials: P
authors.lastname: Thiebaud
authors.forename: Michael B
authors.initials: MB
authors.lastname: Nichol
authors.forename: Simon S K
authors.initials: SS
authors.lastname: Tang
authors.forename: Henry
authors.initials: H
authors.lastname: Solomon
authors.forename: Dennis
authors.initials: D
authors.lastname: Honda
authors.forename: JoAnne M
authors.initials: JM
authors.lastname: Foody
mesh_terms: D000368:Aged; D017311:Amlodipine / Q000008:administration & dosage*; D000069059:Atorvastatin; D002121:Calcium Channel Blockers / Q000008:administration & dosage*; D004338:Drug Combinations; D005260:Female; D006538:Heptanoic Acids / Q000008:administration & dosage*; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage*; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance / Q000706:statistics & numerical data*; D011758:Pyrroles / Q000008:administration & dosage*; D012189:Retrospective Studies
chemical_list: D002121:Calcium Channel Blockers; D004338:Drug Combinations; D006538:Heptanoic Acids; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D011758:Pyrroles; D017311:Amlodipine; D000069059:Atorvastatin