Study objective: To characterize the adverse cognitive effects of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins).
Design: Patient survey-based analysis.
Patients: One hundred seventy-one patients (age range 34-86 yrs) who self-reported memory or other cognitive problems associated with statin therapy while participating in a previous statin effects study.
Measurements and main results: Patients completed a survey assessing statin-associated, cognitive-specific adverse drug reaction (ADR) characteristics, relation of the ADR to specific statin and dose (or potency), and time course of symptom onset and recovery. Visual analog scales were used to assess the effect of the cognitive ADRs on seven quality-of-life domains. Demographic and clinical data were also collected. To target cognitive ADRs with a probable or definite causal relationship to statins, the Naranjo adverse drug reaction probability scale was used: 128 patients (75%) experienced cognitive ADRs determined to be probably or definitely related to statin therapy. Of 143 patients (84%) who reported stopping statin therapy, 128 (90%) reported improvement in cognitive problems, sometimes within days of statin discontinuation (median time to first-noted recovery 2.5 wks). Of interest, in some patients, a diagnosis of dementia or Alzheimer's disease reportedly was reversed. Nineteen patients whose symptoms improved or resolved after they discontinued statin therapy and who underwent rechallenge with a statin exhibited cognitive problems again (multiple times in some). Within this vulnerable group, a powerful relationship was observed between potency of the statin and fraction of trials with that agent resulting in cognitive ADRs (p<0.00001). Quality of life was significantly adversely affected for each of the seven assessed domains (all p<0.00000001).
Conclusion: Findings from the survey suggest that cognitive problems associated with statin therapy have variable onset and recovery courses, a clear relation to statin potency, and significant negative impact on quality-of-life. Administration of a patient-targeted questionnaire is a feasible approach that provides a useful complement to other ADR surveillance approaches.