Mortality Risk Much Higher for Elderly People With Dementia
But incidence of condition could be reduced by addressing various lifestyle factors
FRIDAY, Aug. 6 (HealthDay News) -- Elderly people with dementia have a much higher mortality risk than peers without the condition, but the risk of dementia may be reducible by addressing risk factors such as diet, preventable disease, and mental health, according to a pair of studies published Aug. 5 in BMJ.
Greta Rait, M.D., of the Medical Research Council General Practice Research Framework in London, and colleagues compared survival and mortality in 22,529 subjects (age 60 and older) with dementia and a matched cohort of 112,645 healthy subjects. Mortality risk was found to be much higher for those with dementia: relative risks, 3.68 in the first year after dementia diagnosis, easing to 2.49 in year two. The incidence of dementia over the study period was three to four per 1,000 person-years at risk.
In a second study, Karen Ritchie, Ph.D., of INSERM in Montpellier, France, and colleagues tracked a population of 1,433 elderly subjects (aged over 65) for seven years, during which time 405 developed mild cognitive impairment (MCI) or dementia. The researchers calculated the mean percentage population attributable fractions for MCI/dementia, including crystallized intelligence (18.11 percent), depression (10.31 percent), fruit and vegetable consumption (6.46 percent), diabetes (4.88 percent), and apolipoprotein E with an ε4 allele, a non-modifiable factor, (7.11 percent).
"Increasing crystallized intelligence and fruit and vegetable consumption and eliminating depression and diabetes are likely to have the biggest impact on reducing the incidence of dementia, outweighing even the effect of removing the principal known genetic risk factor," Ritchie and colleagues conclude.
The second study was partly funded by Novartis. Several study authors reported receiving technical support from Novartis.