Cardiac disease was associated with increased risk, particularly for women, of non-amnestic mild cognitive impairment (naMCI), which may be a precursor of vascular and other non-Alzheimer dementias, according to a report published Online First by JAMA Neurology, a JAMA Network publication.

Mild cognitive impairment (MCI) is an important stage for early detection and intervention of dementia, according to the study background.

The study by Rosebud O. Roberts, M.B., Ch.B., M.S., and colleagues at the Mayo Clinic, Rochester, Minn., evaluated 2,719 participants (who were 70 to 89 years of age) at baseline and then every 15 months using a neurological evaluation and a neuropsychological testing. Of 1,450 participants with follow-up, 348 developed incident MCI and 18 developed incident dementia over a median of four years. Of the 348 patients with incident MCI, 231 (66.4 percent) had amnestic mild cognitive impairment (aMCI, which is thought to progress to dementia due to Alzheimer disease), 93 (26.7 percent) had naMCI and 24 (6.9 percent) had MCI of unknown subtype.

"In our population-based elderly cohort, a history of cardiac disease was significantly associated with an increased risk of naMCI. The association varied by sex; men with cardiac disease had the highest risk of naMCI. However, hazard ratio (HR) for the association of cardiac disease with naMCI within the same-sex group was greater among women than men. These findings suggest that cardiac disease is an independent, modifiable risk factor for naMCI in older persons, particularly in women," the authors note.

Cardiac disease was associated with an increased risk of naMCI in men and women combined (hazard ratio, 1.77), however the association varied by sex. Cardiac disease was associated with an increased risk of naMCI (HR 3.07) for women but not for men (HR 1.16). Cardiac disease was not associated with any type of MCI (combined aMCI and naMCI) or with aMCI, according to the study results.

"Cardiac disease is an independent risk factor for naMCI; within-sex comparisons showed a stronger association for women. Prevention and management of cardiac disease and vascular risk factors may reduce the risk of naMCI," the study concludes.

This research was supported by the National Institutes of Health and the Robert H. and Clarice Smith and Abigail van Buren Alzheimer's Disease Research Program and was made possible by the Rochester Epidemiology Project.