Keeping the whole body as healthy as possible could be key to avoiding Alzheimer’s, a study has found.

A wide range of problems not usually associated with mental decline, such as arthritis and stomach complaints, influence the risk of dementia in later life, research has shown.

Scientists in Canada studied 7,239 people aged 65 and older who were free of Alzheimer’s or other forms of dementia. Each participant was asked questions about 19 health problems not previously linked to dementia and assessed at five and 10 years.

The problems included arthritis, trouble hearing or seeing, denture fit, chest, skin or bladder complaints, sinus issues, broken bones and feet or ankle conditions.

After 10 years, 2,915 participants had died, 416 had Alzheimer’s disease and 191 had other forms of dementia. A total of 883 were free from significant mental decline.

Each health problem increased the risk of developing dementia by 3.2 per cent.

Older adults who were generally healthy at the start of the study had an 18 per cent chance of being affected by dementia after 10 years. But for those who had eight and 12 health problems, respectively, the risk increased to 30 per cent and 40 per cent. The findings are published online in the journal Neurology.

Lead researcher Kenneth Rockwood, of Dailhousi University in Halifax, Nova Scotia, said: “Our study suggests that rather than just paying attention to already known risk factors for dementia, such as diabetes or heart disease, keeping up with your general health may help reduce the risk for dementia.”