British researchers say they have found a conclusive link between dementia and certain existing chronic illnesses in the cognitively impaired, a finding that lends more credible evidence associating co-morbidities with memory-related diseases and the positive results from early intervention.

Reporting in a recent issue of the American Journal of Psychiatry, University College London scientists said people with mild cognitive impairment are at higher risk of developing dementia if they have diabetes or psychiatric symptoms such as depression.

The scientists followed nearly 16,000 people across 62 different studies who were diagnosed with MCI, a state between normal aging and dementia in which a person’s mind is functioning less than expected for their age. MCI affects 19% of people aged 65 and over, and around 46% of people with MCI develop dementia within three years, compared with 3% of the general population.

Existing psychiatric conditions made those patients nearly twice as likely to develop dementia, while those with diabetes were 65% more likely to develop dementia, according to the researchers.

While treating diabetes and psychiatric symptoms won’t necessarily reduce an individual’s risk of developing dementia later on, lead author Claudia Cooper, BM, MSc, said lifestyle changes that improve diet and mood might help people with MCI avoid dementia.