No difference was found in the rate of memory or cognitive decline of elderly patients who took statins compared with those who had never used them, a recent study reported.
Researchers examined associations between changes in memory and global cognition and statin use by using brain volume studies from the Sydney Memory and Ageing Study, a longitudinal observational study of cognition in community-dwelling elderly Australians without dementia. Data were collected every two years over the six-year period by psychologists and nurses. Patients were categorized by statin ever use versus never use; continuous statin use during observation versus never use; use of simvastatin, pravastatin, and atorvastatin versus never use; and statin initiation during the study versus never use. Results were published by the Journal of the American College of Cardiology on Nov. 18.
The study included 1,037 participants, 395 statin never-users and 642 statin ever-users. On average, participants had been on statins for nine years. Researchers assessed memory and global cognition, defined as memory plus processing speed, language, visuospatial ability, and executive function, and used five memory tests to assess new learning and short and long-term recall using verbal and visual memory tasks. All participants were offered brain MRI at baseline; 529 patients accepted, and 408 had a repeated MRI two years later.
Statin ever-users and never-users were found to have similar total brain volume, as well as hippocampal and parahippocampal brain volumes, at baseline, with no significant differences noted two years later. The researchers found no significant difference in rate of decline in memory or global cognition between statin ever-users and never-users. Participants who took statins continuously over the study period had significantly higher baseline performance in memory and global cognition compared to never-users, with a similar rate of decline in memory and global cognition over the six-year observation period.
No associations between statin use and cognition were found overall between baseline and six years. In secondary analyses, logical memory decline was significantly faster in male statin users versus male never-users, but there was no significant difference between female statin users and female never-users. An apparent protective effect of statins was seen in the subgroup of patients with heart disease. In this subgroup, statin ever-users had a smaller six-year decline in the total learning memory test score versus never-users. However, in patients without heart disease, there was a comparable rate of decline between statin ever-users and never-users.
The authors wrote, “This study offers reassurance to consumers who hold concerns about harmful statin effects on memory and cognition.” An accompanying editorial agreed, adding, “These data support the view that worries about cognitive impairment should not limit statin use and raise the possibility that statins may favorably alter cognitive trajectories in a group of elders at high risk of Alzheimer's disease.”