Fixed-dose combinations improve medication compliance: a meta-analysis.
BACKGROUND
Compliance with treatment is a sine qua non for successful treatment of chronic conditions like hypertension. Fixed-dose combinations are designed to simplify the medication regimen and potentially improve compliance. However the data on comparison of fixed-dose combination with free-drug regimen to improve patient's medication compliance is limited.


METHODS
We conducted a MEDLINE search of studies using the words fixed-dose combinations, compliance and/or adherence. The inclusion criteria were studies which involved fixed-dose combination versus free-drug components of the regimen given separately. Only studies which reported patient's compliance were included.


RESULTS
Of the 68 studies on fixed-dose combinations, only 9 studies fulfilled the inclusion criteria. Two studies were in patients with tuberculosis, 4 in the hypertensive population, 1 in patients with human immunodeficiency virus (HIV) disease and 2 in the diabetic population. A total of 11,925 patients on fixed-dose combination were compared against 8317 patients on free-drug component regimen. Fixed-dose combination resulted in a 26% decrease in the risk of non-compliance compared with free-drug component regimen (pooled relative risk [RR] 0.74; 95% confidence interval [CI], 0.69-0.80; P <.0001). There was no evidence of heterogeneity in this analysis (chi(2)=14.49, df=8; P=.07). A subgroup analysis of the 4 studies on hypertension showed that fixed-dose combination (pooled RR 0.76; 95% CI, 0.71-0.81; P <.0001) decreased the risk of medication non-compliance by 24% compared with free-drug combination regimen.


CONCLUSIONS
Fixed-dose combination decreases the risk of medication non-compliance and should be considered in patients with chronic conditions like hypertension for improving medication compliance which can translate into better clinical outcomes.
Department of Medicine, Division of Cardiology, St. Luke's-Roosevelt Hospital and Columbia University, New York, NY 10025, USA.
Sripal
S
Bangalore
Gayathri
G
Kamalakkannan
Sanobar
S
Parkar
Franz H
FH
Messerli
D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000008:administration & dosage; D000959:Antihypertensive Agents / Q000008:administration & dosage; D000995:Antitubercular Agents / Q000008:administration & dosage; D002908:Chronic Disease / Q000188:drug therapy*; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000188:drug therapy / Q000453:epidemiology; D019468:Disease Management; D004338:Drug Combinations; D015658:HIV Infections / Q000188:drug therapy; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000453:epidemiology; D007004:Hypoglycemic Agents / Q000008:administration & dosage; D008875:Middle Aged; D010349:Patient Compliance; D019338:Polypharmacy; D014376:Tuberculosis / Q000188:drug therapy
D019380:Anti-HIV Agents; D000959:Antihypertensive Agents; D000995:Antitubercular Agents; D004338:Drug Combinations; D007004:Hypoglycemic Agents