Tuberculosis in young adults and the elderly. A prospective comparison study.

OBJECTIVES

To compare the clinical, bacteriologic, and radiologic features of pulmonary and pleural tuberculosis in young adults and the elderly and determine if any differences exist between both groups.

DESIGN

Prospective recruitment of all patients diagnosed as having pulmonary and pleural tuberculosis in British Columbia, Canada.

SETTING

A population-based sample from a provincial control program TB registry.

PATIENTS

A total of 218 consecutive patients whose conditions were diagnosed between January 1990 and May 1991. We excluded 15 HIV-positive patients whose conditions were diagnosed during this study.

INTERVENTION

Standardized data collection of symptoms, bacteriology, and review of radiology by two readers blind to the clinical and epidemiologic data.

MAIN RESULTS

There were 142 young adult patients and 76 elderly patients. The young adults had a mean age of 41.2 years and the elderly group had a mean age of 75 years of age. Fever (p = 0.002) and night sweats (p = 0.02) were more common in young adults. In culture-proven disease, hemoptysis, fever, and cough were more common in young adult (p = 0.03, 0.02, and 0.01, respectively). There was no difference in the duration of symptoms between the two groups. The odds ratio for cancers other than lung cancer, 3.98 (confidence interval, 1.49, 10.65) in the elderly group was the only significant risk factor to differ between the two groups. Skin test responses to 5TU PPD were positive in 86.2 percent of young adults and 67.6 percent of elderly patients tested (p = 0.03). A total of 79.6 percent of young adults and 88.15 percent of the elderly patients (not significant) were culture positive. Comparison of radiologic findings in young adults vs elderly patients showed no significant differences apart from those with miliary TB 0.7 percent vs 6.7 percent (p = 0.04).

CONCLUSIONS

In this population-based study, young adults were more likely to have hemoptysis, fever, and cough and to have a positive PPD response. Cancer was significantly associated as a risk factor in the older age group. There was no difference in bacteriologically proven disease or radiologic findings between the two groups, apart from the more common occurrence of miliary TB in the elderly.