Utilization patterns of extended-release niacin in Canada: analysis of an administrative claims database.
OBJECTIVE
To evaluate utilization patterns with extended-release niacin (ERN) compared with those observed with other lipid-modifying drugs (LMDs).


METHODS
A random sample of 17% of patients who had at least one LMD dispensation between January 2004 and February 2007 was obtained from the administrative databases of the Régie de l'assurance maladie du Quebec. Primary outcomes included drug adherence, persistence and discontinuation with ERN and other LMDs, and daily maintenance dose attainment (1500 mg and 2000 mg) with ERN at one-year follow-up. Adherence was defined as the sum of days of all dispensations divided by the total number of days of follow-up. Persistence was defined as renewal of prescription before the end of dispensation plus a grace period (50% prescription duration).


RESULTS
Among 26,862 patients, the majority received statins (73.4%), whereas 867 (3.2%) received ERN. The mean age of ERN patients was 62 years and 75% were male. After one year, adherence with ERN was below that of statins (62.0% versus 74.9%), as was persistence (36.1% versus 46.7%), while discontinuation rates were higher (64.0% versus 53.3%). The median time until discontinuation for ERN was shorter than for statins (66 days versus 99 days). After one year, 5.8% of patients were taking 1500 mg or more and 3.2% were on 2000 mg.


CONCLUSIONS
In the present cohort of patients from regular clinical practice in Quebec, ERN use was associated with low prescription rates, inferior adherence and persistence compared with other LMDs, high discontinuation rates, and very low 2000 mg dose attainment.
Dorais
Marc
M
Centre Hospitalier de l'Université de Montréal, Quebec.
Chirovsky
Diana
D
Ambegaonkar
Baishali
B
Sazonov
Vasilisa
V
Davies
Glenn
G
Grant
Susan
S
Lelorier
Jacques
J
D000368:Aged; D015331:Cohort Studies; D003327:Coronary Disease / Q000188:drug therapy*; D016208:Databases, Factual; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D000960:Hypolipidemic Agents / Q000627:therapeutic use*; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D009525:Niacin / Q000627:therapeutic use*; D011792:Quebec; D012189:Retrospective Studies; D012494:Sampling Studies; D016896:Treatment Outcome
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D000960:Hypolipidemic Agents; D009525:Niacin