Frailty as a Risk Factor for Alzheimer's Dementia
by Brain PostsSeveral traditional risk factors have been identified for the future development of Alzheimer's dementia. These include age, lower premorbid educational level, history of head trauma and family history of Alzheimer's. However, despite discovery of these risk factors they fail to completely explain the risk of developing Alzheimer's.A group of researchers from Dalhousie University in Halifax, Canada recently published a study exploring novel non-traditional factors that might influence risk of dementia and death. They constructed a roster of 19 variables linked to frailty but not previously linked to dementia. These variables included items such as:
- vision problems
- hearing problems
- arthritis
- dental problems
- bladder or bowel control problems
- stomach problems
A group of over 7,000 elderly Canadian subjects with normal cognitive function at baseline were rated on these 19 frailty variables and were followed for ten years. Risk for death and dementia in the sample were analyzed with attention to the association with the frailty variables.Individual frailty variables had limited association with risk for death or dementia. However, when combined to produce a frailty index important associations were found. Subjects with higher scores on the frailty index were much more likely to die in the ten-year followup period (65% risk of death in the high index score group compared to only 25% in the low index score group). Additionally, the risk of developing Alzheimer's disease in the ten-year followup period was elevated by higher frailty index scores (50% risk for higher frailty versus 15% for lower index subjects).The research group controlled for possible confounding effects of variables noted to be related to dementia, i.e. age and educational status. The effect of a higher frailty index on Alzheimer's dementia risk persisted after controlling for these variables.The authors note the potential important clinical and public health implications of their findings. Efforts to identify and treat general medical health conditions in the elderly may reduce the risk for incident Alzheimer's disease. Future research in the epidemiology of dementia will need to assess and examine the effect of general medical status.Source: http://brainposts.blogspot.ca/2012/04/frailty-as-risk-factor-for-alzheimers.html