CHICAGO – More liberal lipid targets in elderly patients and lower statin doses might offset the risk of memory decline associated with statin use in these patients, Australian investigators suggested.
Dr. Katherine Samaras and her associates did neuropsychometric testing on 377 subjects 70-90 years old who had been on statins for 2-22 years, and 301 controls who had not taken the drugs. They then repeated the assessments at 2 and 4 years, and calculated composite, normalized z scores for various cognitive functions.
The team found a significantly greater decline in memory z score from baseline among statin users at both 2 and 4 years (4-year z score –0.27 vs. –0.07).
However, statin use was not associated with greater 4-year declines in language, processing speed, or visuospatial or executive functions. Also, metabolic syndrome was not associated with accelerated cognitive decline, Dr. Samaras reported at the joint meeting of the International Congress of Endocrinology and the Endocrine Society.
The analysis controlled for age, sex, education, smoking, the presence of hypertension, diabetes, heart disease, stroke, obesity, and the presence of apolipoprotein E e4 genotype (APOEe4), which increases the risk for Alzheimer’s disease.
Previous stroke was significantly associated with an even greater memory decline among statin users. Smoking and APOEe4 seemed to be, as well, but the trends were not significant.
The subjects were part of the Sydney Memory and Ageing Study, a longitudinal cohort of community-dwelling, well elderly from the affluent part of Sydney. None had dementia.
The findings add weight to the Food and Drug Administration's warning about statin use and memory loss in 2012.
This has "made me look very closely at who I prescribe statins for. People do report cognitive changes" if asked, said Dr. Samaras of the Garvan Institute of Medical Research and the University of New South Wales in Sydney.
To forestall memory loss, "I wonder if we should have a greater range of appropriate lipid targets for the elderly, just as we have for hemoglobin A1c," she said. For now, if an elderly person is "really tightly controlled and well under the benchmark we are trying to reach [with statins], then I reduce the dose," with appropriate follow-up, Dr. Samaras said.
Trials of lipid-lowering therapy should include formal cognitive measurements, as well. "As a prescriber, I’d like to know that data," she said.
The subjects in the study were about 80 years old on average, and about equally split between men and women. The average body mass index was 27.1 kg/m2, and the average fasting glucose level was 5.6 mmol/L. Sixty percent of statin users and 45.9% of nonusers had metabolic syndrome; 15.2% of statin users and 5.5% of nonusers had diabetes.
Australia’s National Health and Medical Research Council funded the work. Dr. Samaras and her colleagues said they had no disclosures.