‘India better be prepared for the 16.9 million people who will live with dementia in 2036’

What was the study all about?

It’s a GoI project and was started in 2009 under the national programme for the healthcare of the elderly. This was a part of the main study and the second phase will begin soon. We analysed 32,000 subjects from the 60+ population and looked
at their brain ageing more intensely to understand the extent of dementia in India.

How did the study diagnose dementia in the sample population?

Dementia diagnosis is questionnaire-based and there is no gold standard like you do for diabetes or Covid and categorise the result as negative or positive. It’s a complex diagnostic process of mapping or examining various parts of brain function, speech capability, thinking capability and memory. Then the questionnaire makes a composite score and concludes that a person may have dementia or not.

As per the Longitudinal Ageing Study in India (LASI), a sample of adults over and above 60 were recruited and were subjected to a rich battery of neuropsychological tests and an informant interview between 2018 and 2020. The study was conducted state-wise, using the 2011 census listing directory of districts, sub-districts (tehsils), which were the primary sampling units. Researchers conducted door-to-door household interviews. For large states, a larger sample size proportionate to the population was considered. In addition, we oversampled individuals aged 65 and older to achieve a better representation of this group.

What were the causes behind dementia?

The number one cause of dementia is Alzheimer’s Disease but it was difficult to segregate it from vascular dementia or frontotemporal dementia as the study was largely based on field work. It doesn’t matter really because from a socio economic and care-giving point of view, all of them would require a similar disease management protocol.

Different levels of education led to differences in various dementia risk factors across states, such as under-nutrition, uncontrolled cardiovascular disease and exposure to indoor air pollution. If prevalence stays the same, the number of people with dementia is projected to reach 16.9 million in 2036 due to an increase in our older population.

What were the other important findings?

The cross-state variation in dementia prevalence was found to be considerable, with the lowest prevalence in Delhi at 4.5 per cent and the highest in Jammu and Kashmir at 11 per cent. According to the research, there were wide variations across
gender and geographical locations.

What are the differences between rural and urban areas?

The study showed dementia is much higher in rural areas, possibly because of low levels of education and awareness. And since the burden of dementia cases is unevenly distributed across states and sub-populations, control protocols might, therefore, require different levels of local planning and support.

What was the reason behind the higher prevalence rate in Jammu and Kashmir? Could post-traumatic stress disorder (PTSD) be the cause?

The Sher-e-Kashmir Institute of Medical Sciences was gathering samples but we are yet to find out the reasons behind the higher prevalence rate in Jammu and Kashmir. We will find answers during phase two of our study. But what I can tell you is that dementia is correlated with hypertension, hearing loss, visual impairment and nutritional deficiencies.

Why Dr Dey?

Dr A B Dey is Professor and Head, Department of Geriatric Medicine, former Dean (Research), Nodal Officer, National Centre for Ageing, AIIMS. He has authored many research papers and has been instrumental in establishing Geriatric Medicine as a sub-speciality in India. His findings have been the basis and evidence for policy formulation and action. He has had a role in the development of the National Programme for Health Care of older people. He has been Chairman of the committee to develop ICE material for the National Programme for Health Care of the Elderly, Ministry of Health and Family Welfare, GoI.