Physical activity levels showed some differences, with lower activity linked to higher impairment, but these results were not crucial.
Published Sep 21, 2025 | 7:00 AM ⚊ Updated Sep 21, 2025 | 7:00 AM
Synopsis: A study in rural Kerala reveals 27% of elderly adults face cognitive impairment, with education and marital status as key protective factors. Higher education reduces impairment risk by 30 times, while marriage offers social support, lowering odds by 24 times. As India’s elderly population grows, addressing cognitive health is critical.
Education and marriage have long been recognised as pillars of social well-being, but new research suggests they may serve as powerful shields against cognitive decline in old age. While formal education builds mental resilience through lifelong learning, marriage provides the social connections that keep ageing minds sharp and engaged.
These protective factors have taken on new urgency as a groundbreaking study from rural Kerala reveals that nearly one in every four older adults is living with cognitive impairment — difficulties with memory, concentration, and decision-making that can affect everyday life.
The research, conducted in Njarakkal Grama Panchayat of Ernakulam district, found that 27 percent of elderly people surveyed showed signs of such decline, with education and marital status emerging as the strongest predictors of cognitive health.
The findings, published this week in the journal Cureus, shine a light on an emerging public health challenge in India’s ageing society. With over 300 million Indians projected to be over 60 by 2050, the study underscores the need to prepare communities and healthcare systems for age-related cognitive issues.
Researchers from Amrita Institute of Medical Sciences, Kochi, surveyed 175 residents aged 60 and above between June 1–14, 2024. Participants underwent cognitive tests using the Mini-Mental State Examination, a widely used screening tool that checks orientation, memory, attention, and language.
“The overall prevalence of cognitive impairment in the study population was 27 percent,” the researchers reported. Among the participants, 29.71 percent had high physical activity levels, 32.57 percent had medium activity levels, and 37.71 percent had low physical activity levels.
The study’s 27 percent prevalence is higher than earlier reports from rural Kerala, such as an 18.6 percent prevalence in a Trivandrum study.
“This elevated prevalence underscores the growing concern of cognitive impairment among rural elderly populations and may reflect gaps in awareness, underdiagnosis, or contextual differences in lifestyle and healthcare access,” the authors noted.
Educational level demonstrated the most striking association with cognitive function. Those with only primary or middle school education were nearly 30 times more likely to show impairment compared to those with a university degree. Only 4.8 percent of university-educated individuals experienced cognitive impairment, whereas the prevalence soared to 47.8 percent among those with only primary or middle school education.
“Individuals who had only primary or middle school education showing markedly higher odds of cognitive impairment compared to those with higher secondary or university education,” the multivariable analysis revealed.
The researchers explained that education builds what scientists call “cognitive reserve” — a mental resilience that helps the brain develop protection against age-related decline. This means that learning and mentally stimulating activities throughout life create a buffer against cognitive deterioration.
“Even a few more years of schooling may delay or reduce cognitive problems in later life,” the authors noted. Higher educational attainment contributes to greater cognitive reserve and improved performance in domains such as memory, attention, and reasoning. The findings collectively underscore the importance of lifelong learning and cognitive engagement in preserving mental acuity with aging.
Marital status emerged as the second most significant predictor of cognitive health. Elderly individuals who had never married were 24 times more likely to show decline than those who were married at least once. Unmarried individuals showed a higher prevalence of cognitive impairment at 52 percent compared to their married counterparts at 16.8 percent.
“Individuals who were never married had significantly higher odds of cognitive impairment compared to those who were ever married,” the multivariable analysis confirmed.
The protective effect of marriage stems from the regular social interaction and emotional support it typically provides, both of which keep the brain active and engaged. Studies worldwide have shown that loneliness and isolation accelerate mental decline, while companionship, shared activities, and family ties offer protection.
“Individuals who were ever married demonstrated a lower prevalence of cognitive impairment, highlighting the potential protective role of social support,” the researchers explained.
Marriage fosters cognitive health through companionship, emotional connection, and participation in mentally stimulating activities. Social isolation, emotional neglect, and reduced cognitive engagement — conditions more common among those living alone — are linked with a heightened risk of cognitive impairment.
The study revealed significant disparities across socioeconomic lines. People from below-poverty-line households, as marked by ration cards, showed higher rates at 39.7 percent compared to those above the poverty line at 19.6 percent.
However, after adjusting for other variables in the multivariable model, socioeconomic status was not found to be significantly associated with cognitive impairment.
Body mass index also showed initial associations with cognitive function. Half of underweight participants showed impairment, compared to 20 percent of overweight elders.
Underweight individuals exhibited a 50 percent prevalence of cognitive impairment compared to those who were of normal weight at 32.8 percent or overweight at 20 percent. However, BMI was not found to be significantly associated with cognitive impairment after adjusting for other variables.
The study found that male participants showed a higher prevalence of cognitive impairment at 76.3 percent compared to female participants at 61.6 percent. This finding was notable as men had higher rates than women, contrary to some expectations about gender differences in cognitive aging.
Physical activity levels showed some differences, with lower activity linked to higher impairment, but these results were not statistically significant.
Although physical activity is widely acknowledged for its role in preventing chronic diseases and reducing mortality, the study did not find a statistically significant association between physical activity and cognitive function.
“This discrepancy may be attributed to various factors, including the type, intensity, and consistency of physical activity, as well as genetic predisposition, socioeconomic conditions, behavioral traits, and age-related variations,” the researchers explained. While low-intensity or irregular activity may not substantially influence cognitive outcomes, it can still contribute to improved physical health and overall well-being.
Despite the lack of statistical significance, the observed trends suggest that physical activity remains a promising modifiable factor. Aerobic exercise has been shown to positively affect cognitive function in other studies.
In Kerala, which has the highest proportion of elderly citizens in India at 16.5 percent, the cognitive health challenge is particularly pressing. As life expectancy rises, the risk of dementia and related disorders also increases.
Cognitive impairment can range from mild forgetfulness to severe dementia. While mild cases allow people to remain independent, severe impairment can make even simple tasks — handling money, cooking, or holding a conversation — difficult.
“This study identified a 27 percent prevalence of cognitive impairment among older adults in rural Ernakulam, with significant associations observed for sociodemographic factors such as marital status and educational attainment,” the authors concluded.
“These findings underscore the growing burden of cognitive impairment among the elderly in rural Kerala, reflecting broader demographic and social transitions.”
(Edited by Amit Vasudev)
