Summary
At this time there is insufficient evidence to confidently conclude that statins can cause or contribute to clinically meaningful cognitive impairment. The current evidence demonstrating an association between statins and cognitive impairment has several limitations, including: failure to establish a cause-effect relationship, inability to account for all confounders, lack of controls, inconsistent assessments of cognition, and generally healthy study populations that do not necessarily reflect typical statin users in practice. When balanced with the established vascular benefits of statins and the evidence demonstrating either neutral or possibly beneficial effects on cognition (note that statins are not FDA- or Health Canada–approved for treatment or prevention of cognitive impairment), the risk of cognitive impairment should not change current practice with respect to statin use.
The aforementioned facts notwithstanding, if statin-associated cognitive impairment is suspected, confounding factors, such as concomitant medications, medical conditions, or risk factors for cognitive impairment, should first be assessed. If the statin is still suspected, a trial withdrawal period of 1–3 months is recommended and the patient can be reassessed for symptom resolution. Switching to a hydrophilic agent (eg, pravastatin or rosuvastatin) may be an option for patients who experience cognitive adverse effects while receiving a lipophilic statin. Other lipid-lowering agents may also be considered as viable alternatives in persistent statin-associated cognitive impairment. Routine neurocognitive testing is not recommended for patients taking statins, nor are changes to current practice with respect to statin use.