Prevalence of Latent Tuberculosis Infection among Spouses and First-Degree Relatives of Pulmonary Tuberculosis Cases in South India.

BACKGROUND

A study was conducted to examine variations in latent tuberculosis infection (LTBI) risk factors among household contacts (HHCs) of tuberculosis (TB) patients.

OBJECTIVES

The objective of this study was to assess LTBI prevalence among first-degree relatives (FDRs) and spouses of TB patients and identify associated risk factors.

MATERIALS AND

METHODS

A cohort study at JIPMER under Regional Prospective Observational Research for TB India included HHCs of newly diagnosed pulmonary TB patients. Prevalence ratios with 95% confidence intervals (CIs) were calculated using generalized linear modeling.

RESULTS

Among 1318 HHCs of 548 TB patients, the mean ages were 45.2 (13.7) and 29.5 (16.1) years, respectively. LTBI prevalence was 58.1%, with 0.5% progressing to active TB. Spouses had a higher LTBI prevalence (64.2%) than FDR (55.8%), with a significantly elevated risk (PRR: 1.42, 95% CI: 1.11-1.83). Older age (40-59 and ≥60 years), bed-sharing, female gender, prolonged exposure, undernutrition, overweight/obesity, and alcohol use were linked to higher LTBI prevalence. Female spouses spent more time caring for index cases than male spouses.

CONCLUSION

Spouses had a higher LTBI prevalence than FDR. Screening programs should prioritize female spouses, undernourished individuals, overweight/obese individuals, and alcohol users to reduce TB transmission.