If you are overcome by a sense of hopelessness, especially during your mid or later life, it could be a sign that you are heading for dementia — the mental decline caused by Alzheimer’s.

“Prevalence and costs of AD (Alzheimer disease) and other dementia are projected to rise dramatically during the next 40 years unless a prevention or a cure can be found,” write researchers from University of California, San Francisco.

“Therefore, it is critical to gain a greater understanding of the key risk factors and etiologic underpinnings of dementia from a population-based perspective,” the Archives of General Psychiatry journal quoted them as saying.

Some symptoms of early dementia are forgetting names, appointments, losing things, difficulty in driving, cooking, doing household chores, personality changes (becoming withdrawn), uncharacteristic behaviour, mood swings, and behaviour disorder.

Deborah E. Barnes from the university and the San Francisco Veterans Affairs Medical Centre and colleagues evaluated data from 13,535 long-term Kaiser Permanent members.

Barnes also examined depressive symptoms assessed in midlife (1964-73) and in late life (1994-2000) and risks of developing dementia.

Depressive symptoms were present in 14.1 per cent of study participants in midlife, 9.2 per cent in late life and 4.2 per cent in both.

During six years of follow-up, 22.5 per cent of patients were diagnosed with dementia and 5.5 per cent with Alzheimer disease.

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