Abstract
BACKGROUND: Tuberculosis (TB) continues to be a public health challenge in Saudi Arabia, particularly for the elderly. This study was conducted to estimate mortality per 1000 person-year among TB and resistant TB cases and to identifying factors associated with mortality. METHODS: This is a retrospective cohort study of 713 new TB cases at King Abdulaziz Medical City in Riyadh diagnosed between January 1, 2000, and December 31, 2016. Patient medical records and microbiology lab databases were used to identify TB cases. Through reviews were conducted of patients' medical records, including physician notes, physical examinations, radiology (scans and imaging), laboratory tests, and follow-up notes. Collected data include demographic information, clinical features, diagnoses, comorbidities, and death rates. RESULTS: Of the 713 TB patients included in this study, 110 died, giving an average mortality rate of 22 per 1000 person-years (PY; 95% CI: 18.2-26.4). Elderly patients (≥ 60 years) had a higher mortality rate of 36.5 per 1000 PY (95% CI: 28.9-45.5). As age increases by one year, the hazard of mortality increase by 2.4% (aHR: 1.024 [95% CI: 1.009-1.039, P = 0.002]). Higher hazard of mortality was found among males (aHR: 2.014 [95% CI: 1.186-3.418, P = 0.010]). Patients with respiratory and other types of comorbidities and cancer had a higher mortality hazard (aHR: 1.898 [95% CI: 1.005-3.582, P = 0.048]; aHR: 2.346 [95% CI: 1.313-4.192, P = 0.004]; aHR: 3.292 [95% CI: 1.804-6.006, P = 0.001]), respectively. Multidrug-resistant TB (MDR-TB) was found in 2 cases (0.28%) (95% CI: 0.08-1.02), 1.68% were resistant to only one antibiotic, 0.14% had rifampicine-resistant TB (RR-TB), 0.28% had MDR-TB, and 0.14% had extensively drug-resistant TB (XDR-TB). CONCLUSIONS: The mortality rate among TB patients was found to be 22 per 1000 person-year at our center. TB was associated with high mortality rates among males, the elderly, and patients with cancer, respiratory illness, and other comorbidities. Future clinical practice should include establishing an efficient TB diagnostic program and continued hazard assessment of TB treatment options.