Treatment with statins in the elderly population is not associated with accelerated memory dysfunction, greater decline in global cognitive function, or brain volume changes over 2 years, according to study results published in The Journal of the American College of Cardiology.
While many guidelines recommend statin treatment to prevent cardiovascular and cerebrovascular morbidity and mortality, there are consumer concerns regarding the possible effect of this treatment on cognitive function, because memory and/or cognitive changes are the second most common reported adverse event with statins.
The goal of the study, the Sydney Memory and Ageing Study (MAS), was to investigate the changes in memory and global cognition associated with statin therapy over 6 years and changes in brain volume over 2 years.
The MAS was a longitudinal, prospective, observational, population-derived cohort of non-demented Australians aged 70 to 90 years at baseline. Data were collected every 2 years over a 6-year period.
The study cohort included 1037 patients: 395 were statin naïve and 642 had ever used statins. The mean duration of statin use at baseline was 9.1 years. At baseline, patients who had reported ever using statins were slightly younger, had higher body mass index, and had lower diastolic blood pressure than did never users. Over the observation period, 68% of patients who had used statin were continuous users.
The primary outcome measures included 2 end points: memory and global cognition, as assessed by neuropsychologic testing every 2 years. In a subgroup of 526 patients, magnetic resonance imaging was used to assess changes in total brain, hippocampal, and parahippocampal volume.
Over 6 years of observation, there was no significant difference in the rate of decline in memory and global function between patients who had ever used statins and patients who had never used statins. The trend was similar between continuous statin users and never users. Furthermore, there was no difference in rates of decline in memory and global cognition over 6 years between each statin subgroup (atorvastatin, simvastatin, and pravastatin) and the group of patients who never used statins.
Statin initiation was not associated with a change in global cognition performance or rate of decline, but was associated with an attenuation in the rate of decline of memory (P =.038).
Analyses to examine the possibility that statins may unmask memory difficulties in patients predisposed to cognitive impairment revealed no interaction between statins, risk factors for dementia, and changes over 6 years in memory and global cognition.
The researchers noted protective associations were found for some aspects of memory testing. Exploratory analyses of specific memory tests revealed a significant interaction between statin ever use and heart disease on decline in total learning. There was also evidence that supported apolipoprotein Eε4 carriage and slower decline in long-delayed recall in men who reported statin use compared with men who never used statins.
No difference in brain volume changes was found between statin users and never users.
The researchers acknowledged several study limitations, including its observational design, potential selection bias and survivor bias, as well as baseline differences between the groups for dementia risk factors. In addition, patients with advanced cognitive impairment were excluded from the study.
“This study offers reassurance to consumers who hold concerns about harmful statin effects on memory and cognition,” concluded the researchers.
Samaras K, Makkar SR, Crawford JD, et al. Effects of statins on memory, cognition, and brain volume in the elderly. J Am Coll Cardiol. 2019;74(21):2554-2568. doi:10.1016/j.jacc.2019.09.041