Here are four common non-modifiable risk factors of disease that have been associated to the development of dementia:
Non-Modifiable Risk Factors
The greatest risk factor for dementia is age. Although age increases risk, dementia is not a normal part of ageing, and ageing is not itself a cause of dementia.
Watch Dr Joshua Kua, a Geriatric Psychiatrist, answer whether dementia runs in the family:
Source: Agency for Integrated Care
There are more than 20 genes which affect a person’s risk of developing dementia. The gene APOE was the first known to increase a person’s risk of developing Alzheimer’s disease, which is the most common cause of dementia, and it is currently still the strongest risk gene known. There are also genes which directly cause dementia, but these deterministic genes (genes that guarantee the development of a condition) are rare – they are estimated to account for less than 1% of dementia cases, and cause young-onset forms in which symptoms usually develop before the age of 60.
Women are more likely to develop Alzheimer’s disease than men, even when the fact that women’s lifespans are on average longer than men’s is accounted for. The reasons for this are unclear.
In a 2008 study investigating the prevalence of dementia in Singapore, Malays were found to have twice the risk of developing Alzheimer’s Disease than Chinese, while Indians had more than twice the risk of developing Alzheimer’s Disease and Vascular Dementia than Chinese. The reasons for this ethnic difference require further investigation.1
- Sahadevan, S., Saw, S. M., Gao, W., Tan, L. C., Chin, J. J., Hong, C. Y., & Venketasubramanian, N. (2008). Ethnic differences in Singapore’s dementia prevalence: The stroke, Parkinson’s disease, epilepsy, and dementia in Singapore study. Journal of the American Geriatrics Society, 56(11), 2061-2068. doi: 10.1111/j.1532-5415.2008.01992.x.