Table 6. Crude and adjusted risk factors for isolation of NTM from sputum samples, Zambia, August 2002–March 2003*.
| Factor | Univariate analysis, OR (95% CI) | Multivariate analysis, OR (95% CI)† |
|---|---|---|
| Hospitalized | 1.1 (0.7–1.7) | NS |
| Age >25 y | 1.3 (0.8–2.5) | NS |
| Sex (female) | 1.1 (0.7–1.7) | NS |
| Underweight (BMI <18) | 1.6 (1.0–2.7) | 1.7 (1.0–2.9) |
| Mycobacterium tuberculosis infection | 1.1 (0.6–2.0) | NS |
| Previous treatment for TB | 1.7 (0.8–3.7) | NS |
| HIV positive | 1.3 (0.8–2.1) | NS |
| Used tap water | 2.2 (1.3–3.8) | 2.0 (1.1–3.5) |
| Used alcohol | 0.9 (0.4–1.9) | NS |
| Smoker | 0.6 (0.2–1.6) | NS |
| Used unboiled milk | 1.3 (0.7–2.3) | NS |
| Farmer | 1.0 (0.6–1.5) | NS |
| Chest radiograph compatible with TB but culture negative for M. tuberculosis | 4.7 (1.6–13.9) | NS |
*NTM, nontuberculous mycobacteria; OR, odds ratio; CI, confidence interval; NS, not significant; BMI, body mass index; TB, tuberculosis. †Stepwise backward elimination.