A cross-sectional study on prevalence of cognitive impairment and its associated factors among the elderly in an urban area of Chennai, India

Rajesh J., Ramasubramanian R., Santhanam R. S.


Background: Elderly people often experience cognitive decline with aging. Existing longitudinal studies report that older adults with mild cognitive impairment (MCI) have a 10-15% annual risk of converting to probable Alzheimer’s disease (AD). Objectives were to determine the prevalence of cognitive impairment among the elderly in an urban area of Chennai and to assess the factors associated with cognitive impairment among the elderly.

Methods: This Community based Cross sectional study was conducted between July and October 2019 among 77 individuals aged 60 years and above from an urban area in Chennai, Pudupet. After the institutional ethics committee approval, subjects were interviewed with a pre-designed semi-structured questionnaire followed by administration of standardized mini mental state examination (SMMSE) tool and scoring. Data was analysed using relevant descriptive and inferential statistics with trial version of SPSS.v.25. and OpenEpi software.

Results: The overall prevalence (95% CI) of cognitive impairment was 35.06 % (25.35%, 46.20%). Its prevalence among males and females were 26.08 % (12.55%, 46.47%) and 38.88 (27.04%, 52.21%) respectively. The mean age (95% CI) of study subjects with cognitive impairment was 66.37 years (64.58, 68.16). Those subjects who led a solitary life, had less than 10 years of schooling, used kerosene as cooking fuel and consumed bore well water had significant association with cognitive impairment.

Conclusions: Usage of cooking fuel like LPG and consumption of filtered and purified water could minimize cognitive impairment. Early detection of cognitive impairment would improve the health care and quality of life of the elderly.


Cognitive impairment, Dementia, SMMSE, Elderly mental health

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