Mumbai: Alzheimer’s cases in India could be up to five times higher than the projected number, as most cases go unreported, experts said during a webinar on World Alzheimer’s Day organised by Mahajan Imaging & Labs.
An estimated 8.8 million Indians older than 60 years have dementia, according to a 2023 study titled ‘Prevalence of dementia in India: National and state estimates from a nationwide study.’
But experts believe this number could be much higher.
Dr. Vinit Suri, Senior Consultant Neurologist, Apollo Hospital, said “India has about 8.8 million to 10 million dementia patients, out of which nearly 70 per cent are Alzheimer’s cases. These are only patients who have actually been registered in hospitals. There is a large number of patients in villages and small towns who have dementia but never get registered anywhere as we don’t have big registries. I think the real number is not 8.8 million, it’s probably even four to five times higher.”
As the Indian population ages, cases could only go up, Suri warned.
“The risk of Alzheimer’s increases with every five years of age. For example, the risk at 65 is about 2.5 per cent, while for those above 70 and 75 it is much higher. With an ageing population, and with people surviving cardiovascular disorders and strokes thanks to better management, we are going to see a rise in patients with both Alzheimer’s and non-Alzheimer’s dementia.”
Prevention begins with exercise and sleep
Even as India improves the management and diagnosis of Alzheimer’s, doctors stressed on the importance of prevention through maintaining a healthy lifestyle.Suri explained, “Physical exercise comes first, even ahead of mental exercise. Thirty to 45 minutes of exercise every day is the single most important step in preventing memory loss and the onset of dementia.
“Second, surprisingly, is sleep. Six to eight hours a night is extremely important, because studies have shown that the brain clears tau and amyloid (proteins that form tangles inside brain cells and plaques between them causing Alzheimer’s) deposits during sleep. People with poor sleep, sleep disorders or a disrupted circadian rhythm are likely to be affected.
“Third, are mental and social activity: learning new things and staying socially engaged. Elderly people who go to the club and play bridge every day are interacting, using their minds and learning, and that matters a lot.”
Blood tests and PET scans enable early detection
Beyond lifestyle changes, earlier detection is becoming possible with newer diagnostic tools.
Explaining the role of diagnostics, Dr. Harsh Mahajan, Founder & Chairperson, Mahajan Imaging & Labs and Mentor, FICCI Health, said, “Blood-based biomarkers can now tell us 15, even 20 years ahead, that a person may go on to develop Alzheimer’s. And an FDG [fluorodeoxyglucose] PET scan can show reduced metabolism, or hypometabolism, in certain parts of the brain while the person is still at the pre-Alzheimer’s stage. So even before any change in cognition, we can say this person is likely to develop mild cognitive impairment, or later Alzheimer’s.”
“These techniques are highly relevant, and key to treating Alzheimer’s,” Mahajan added.
Dr. Ritu Verma, Director – PET CT & Nuclear Medicine, Mahajan Imaging & Labs, added, “PET imaging provides a functional perspective that cannot be obtained from structural imaging alone. In selected patients, FDG PET can help identify patterns of altered brain metabolism associated with neurodegenerative disease. Its value is greatest when the findings are interpreted with the clinical assessment, MRI and biomarker results rather than viewed in isolation.”
The blood biomarker test, introduced in India in January this year, has also proved to be a non-invasive way of testing for Alzheimer’s, making assessment simpler and more accessible.
Dr. Shelly Mahajan, Lab Director, Mahajan Imaging & Labs, said, “The development of blood-based biomarkers is an important step in making Alzheimer’s-related biological assessment simpler and more accessible. From a laboratory perspective, the pTAU217/βAmyloid1-42 ratio provides a measurable indication of disease-associated pathology through a blood sample. When interpreted appropriately with the clinical and imaging findings, it can help bring greater clarity to the diagnostic process.”
