Objective: To investigate the clinical differences between old and young patients infected with Mycobacterium tuberculosis in a developing country.
Design: Retrospective chart and chest radiograph review.
Setting: A university-affiliated teaching hospital.
Patients: The medical records of patients with documented tuberculosis (TB) from January 1990 through December 1991 were analyzed. Clinical assessment included sex, age, diagnosis at first visit, past history, symptoms and signs, laboratory data, X-ray findings, bacteriological examinations, outcome, time elapsed from first visit to initiation of anti-TB therapy and the major determinants for starting anti-TB therapy. Statistical significances were analyzed by Student's t test and chi 2 tests.
Results: Among 205 patients with culture-proven TB, 57 were 65 years of age and older (range, 65 to 91; mean, 73) and 148 under 65 years of age (range, 16 to 64; mean, 41). There was a higher incidence of previous TB (26.3% vs. 16.2%) and diabetes mellitus (24.5% vs. 14.3%) in the elderly patients. Initial diagnosis of TB at first visit was less frequent in the elderly than in the young group (38.6% vs. 47.3%), although symptoms and signs at first visit were similar in each of the age groups. Radiographic presentation with mass lesions was more frequently encountered in elderly patients (10.5% vs. 2.1%, P < .05). Elapsed time from the first visit to suspicion of TB and the initiation of anti-TB therapy was frequently delayed in elderly patients (22 +/- 23 vs. 13 +/- 20 days, P < .05). The incidence of drug-resistance (39% vs. 16%, P < .05) and unfavorable response to anti-TB therapy (17.5% vs. 3.4%, P < .05) were significantly higher in the older patients.
Conclusions: Although clinical presentation of TB in the elderly did not differ significantly from that in younger patients, this study showed that diagnosis and treatment were more often delayed in the elderly, and there was a higher incidence of treatment failure.