Background:
Niacin has proven lipid-modifying efficacy and cardiovascular benefit. Previous cross-sectional and retrospective studies have suggested that niacin-induced flushing (NIF) significantly limits patient adherence to therapy. We conducted a one-year ‘real-world’ prospective observational study to characterize the impact and severity of NIF symptoms in subjects newly prescribed extended-release (ER) niacin.
Methods:
Subjects were surveyed daily during week 1 of therapy and thereafter via telephone at weeks 5, 9, 13 and months 6, 9 and 13. Surveys included the Global Flushing Symptom Score (GFSS), Flushing Impact Questionnaire (FIQ), and Treatment Satisfaction Questionnaire for Medication (TSQM).
Results:
A total of 306 subjects were recruited of which 43.5% (n=133) discontinued ER niacin by the end the study. Among those who discontinued, the median duration of ER niacin use was 95 days (range 2-402 days). At discontinuation, 3 (2.3%) subjects were on 250mg, 71 (54%) on 500mg, 1 (0.8%) on 750mg, 27 (20.3%) on 1000mg, 6 (4.5%) on 1500mg, and 4 (3.1%) on 2000mg. Dose was not available for 21 subjects. Over half of the discontinuers experienced flushing symptoms; 82% reported moderate to extreme flushing (GFSS≥4) and 68% reported severe to extreme (GFSS≥7) prior to discontinuation. About 74% of the discontinuers reported that moderate was the greatest degree of flushing they could tolerate before discontinuation. Those who discontinued and reported experiencing flushing side effects reported high degrees of impact in the FIQ Irritation/Frustration domain: mean (SD) 3.0 (1.3) (0=not at all, 4=extremely) and high dissatisfaction due to side effects as measured by the TSQM Side Effect domain: mean (SD) 63.3 (33.8) (0=extremely dissatisfied, 100=extremely satisfied). In addition, subjects who reported moderate or greater flushing bother during week 1 were 3.3 times more likely to discontinue due to flushing than those who reported less bother (95% CI: 1.01-10, p<0.05).
Conclusion:
Results from this study suggest that in a “real-world” setting, flushing side effects are bothersome and have an impact on continuation of ER niacin therapy. Further research is needed into alternative methods for increasing ER niacin acceptability.