Table 2.
Demographic and clinical characteristics associated with laboratory-confirmed tuberculosis among patients admitted with severe respiratory illness (acute and chronic) that were tested for tuberculosis and influenza at four sites in South Africa, June 2010- December 2011
| Characteristic | Laboratory confirmed tuberculosis n/N (%) | Unadjusted odds ratio (95% CI) | P value | Adjusted odds ratios (95% CI) | P value | |
|---|---|---|---|---|---|---|
| Age group (years) | 0-4 | 55/571 (10) | Reference | Reference | ||
| 5-24 | 47/270 (17) | 1.97 (1.3-3.0) | 0.001 | 1.36 (0.8-2.3) | 0.233 | |
| 25-44 | 249/1378 (18) | 2.1 (1.5-2.8) | <0.001 | 1.37 (0.9-2.06) | 0.120 | |
| 45-64 | 90/611 (15) | 1.6 (1.1-2.3) | 0.008 | 1.11 (0.7-1.7) | 0.628 | |
| 65+ | 16/129 (12) | 1.3 (0.7-2.4) | 0.348 | 0.94 (0.5-1.9) | 0.872 | |
| Site | Chris Hani Baragwanath | 141/1618 (9) | Reference | Reference | ||
| Mapulaneng & Matikwana | 23/144 (16) | 1.99 (1.2-3.2) | 0.005 | 1.4 (0.8-2.3) | 0.228 | |
| Edendale | 49/385 (13) | 1.5 (1.1-2.2) | 0.016 | 0.9 (0.6-1.4) | 0.668 | |
| Klerksdorp/Tshepong | 244/812 (30) | 4.5 (3.6-5.6) | <0.001 | 1.9 (1.4-2.6) | <0.001 | |
| Influenza status | Negative | 423/2650 (16) | Reference | |||
| Positive | 34/309 (11) | 0.7 (0.5-0.9) | 0.023 | |||
| HIV status | Negative | 89/862 (10) | Reference | |||
| Positive | 335/1877 (18) | 1.9 (1.5-2.4) | <0.001 | |||
| Underlying medical condition* | No | 426/2652 (16) | Reference | |||
| Yes | 31/307 (10) | 0.6 (0.4-0.9) | 0.007 | |||
| Duration of symptoms prior to admission | <7 | 190/1884 (10) | Reference | |||
| ≥7 | 255/1012 (25) | 3.0 (2.4-3.7) | <0.001 | |||
| Pneumococcal co-infection on PCR** | No | 400/2435 (16) | Reference | Reference | ||
| Yes | 18/214 (8) | 0.5 (0.3-0.8) | 0.003 | 0.5 (0.3-0.9) | 0.016 | |
| Oxygen therapy | No | 337/1869 (18) | Reference | Reference | ||
| Yes | 120/1086 (11) | 0.6 (0.4-0.7) | <0.001 | 0.7 (0.5- 0.9) | 0.007 | |
| Receiving TB treatment at time of admission | No | 25/158 (16) | Reference | |||
| Yes | 10/49 (20) | 1.4 (0.6-3.1) | 0.456 | |||
| Started on TB treatment | No | 205/2301 (9) | Reference | Reference | ||
| Yes | 251/647 (39) | 6.5 (5.2-8.0) | <0.001 | 4.6 (3.5-6.0) | <0.001 | |
| Duration of hospitalisation (days) | ≤7 | 279/1913 (14) | Reference | |||
| >7 | 174/1029 (17) | 1.2 (0.96-1.6) | 0.096 | |||
| Season | Summer | 57/366 (15) | Reference | |||
| Autumn | 78/449 (17) | 1.1 (0.8-1.6) | 0.492 | |||
| Winter | 178/1027 (17) | 1.1 (0.8-1.6) | 0.441 | |||
| Spring | 144/1117 (13) | 0.8 (0.6-1.1) | 0.194 | |||
| Died | No | 421/2757 (15) | Reference | |||
| Yes | 35/195 (18) | 1.2 (0.8-1.8) | 0.318 |
HIV – human immunodeficiency virus; ICU– Intensive Care Unit, TB-Tuberculosis, CI – confidence interval.
Analysis includes 2029 individuals with severe acute respiratory illness and 930 with severe chronic respiratory illness.
*Underlying conditions included any of the following: Asthma, other chronic lung disease, chronic heart disease (valvular heart disease, coronary artery disease, or heart failure excluding hypertension), liver disease (cirrhosis or liver failure), renal disease (nephrotic syndrome, chronic renal failure), diabetes mellitus, immunocompromising conditions excluding HIV infection (organ transplant, immunosuppressive therapy, immunoglobulin deficiency, malignancy), neurological disease (cerebrovascular accident, spinal cord injury, seizures, neuromuscular conditions) or pregnancy. Comorbidities were considered absent in cases for which the medical records stated that the patient had no underlying medical condition or when there was no direct reference to that condition.
**lyt A PCR positive for Streptococcus pneumoniae on blood specimen.
Other variables that were evaluated but not presented in the table because they were not significant on univariate analysis were sex, influenza type, concurrent bacterial infection, antibiotic prescribed on admission, admission to intensive care unit, and smoking and alcohol intake for patients ≥12 years.