Risk Factors for Tuberculosis in Elderly: Prevalence and Population-attributable Risk

Undernourishment, alcohol use, smoking, diabetes, and HIV are the known risk factors for tuberculosis (TB) with a high population-attributable fraction. Of the total TB cases notified in India, one-fifth are among the elderly, and malnutrition is the most common cause. To estimate the prevalence of nutritional, behavioral, environmental, and clinical risk factors for TB among the elderly (>60 years) in selected rural areas of Puducherry, India.

A cross-sectional study was conducted among four villages of Puducherry in 2023. Risk factors for TB were captured as reported by the participant. The Mini Nutritional Assessment (MNA) Scale and Global Leadership Initiative on Malnutrition (GLIM) criteria were used to assess malnutrition. Household Food Insecurity Access Scale was used to assess food insecurity.

A total of 214 elderly were included; the mean (standard deviation) age was 68 (8) years. The prevalence of malnutrition using GLIM criteria and MNA was 20.1% (95% confidence interval [CI]; 15.2%-26.0%) and 11.2% (95% CI; 7.6%-16.2%), respectively. The prevalence of other risk factors like alcohol use, tobacco use, overcrowding, contact history, and diabetes was 6.1%, 30.2%, 46.2%, 2.8%, and 31.8%, respectively. Food insecurity was reported in 12.6% of the households. The population-attributable fraction was the highest for malnutrition by GLIM criteria (15%), followed by diabetes (11%).

One in three had more than three risk factors, and nine in ten had at least one risk factor for TB. Screening known risk factors for TB in the elderly helps in the early detection of TB and prevention.