Dosage, titration, and gaps in treatment with extended release niacin in clinical practice

ABSTRACT

Objective: To examine the dosage, titration patterns, and gaps in treatment of newly-initiated ER niacin in clinical practice.

Research design and methods: Historical cohort study using the Ingenix Lab/Rx database. Patients were at least 20 years old, received an initial, index ER niacin prescription between January 1, 2001 and June 30, 2003, and had no ER niacin use in the preceding 12 months. Follow-up data were collected for at least 6 months after the index date.

Main outcome measures: Average daily dosage (ADD) and titration patterns of ER niacin therapy at defined time points after the index prescription, and the incidence and timing of continuous gaps of ≥30 days in ER niacin therapy.

Results: A total of 14 386 patients initiating ER niacin were followed for a mean of 6.5 months after the index prescription. The ADD of the initial ER niacin prescription was ≤500 mg for 65 % of patients; most of the remaining patients (33 % ) initiated with an ADD of > 750 mg. Forty percent of patients experienced a ≥30-day gap in therapy immediately after the first prescription. Almost 80 % had at least one ≥30-day gap in therapy during the post-index period, and the ADD of the last prescription prior to discontinuation was ≤500 mg in 53 % of these patients. About half of the patients using ER niacin at 12 weeks and 39 % of patients using it at 24 weeks were still receiving ≤500 mg per day. Only 47 % of ER niacin users reached the recommended daily maintenance dose of ≥1000 mg and only 7.6 % reached the dose of 2000 mg.

Conclusions: A considerable proportion of new ER niacin users failed to reach recommended daily maintenance dosages in clinical practice. The main limitations of the study include its reliance on administrative data, inability to capture over-the-counter niacin use, and evaluation of reasons for suboptimal titration. Future research should determine the extent to which gaps in ER niacin therapy and failure to titrate to optimal dosages are due to poor tolerability, physician practice, or other factors.

Key words: :

• Compliance
• Coronary disease
• Drug therapy
• Hyperlipidemia
• Niacin
• Persistence

Acknowledgements

Declaration of interest: Financial support for this study was provided by Merck & Co., Inc. The authors appreciated the medical writing assistance of Melissa Stauffer, PhD, and Victoria Stern in collaboration with SCRIBCO.