Survival analysis of asthma patients attended to at Chitungwiza Central Hospital in Zimbabwe

Abstract Background Asthma is one of the leading global public health problems with an estimated 300 thousand deaths occurring annually worldwide. Deaths due to asthma in Zimbabwe reached 1 301 or 1.02% of total deaths in 2014. The association between asthma survival and socio-demographic and pathologic factors has not been done in Zimbabwe. We aimed to determine the survival of asthma patients at Chitungwiza Central Hospital in Zimbabwe over a period of 20 years. Methods Records for 158 asthma patients were analysed in this retrospective cohort study. The patient records were sampled from the computerised health information department at the hospital. Data were collected using a patient record checklist which was divided into four sections: (i) demographic information, (ii) clinical characteristics of asthma patients, (iii) health service utilization and (iv) asthma self-management. Descriptive data analysis was performed using the Kaplan Meier survival function curves. The Kaplan Meier survival curves were differentiated by the log-rank test, median survival times and mortality rates. Significant hazard ratios were used for multivariate cox regression model and a test on proportional hazards assumption based on Schoenfeld residuals was conducted. Results The total follow-up time was 2208 person years. The majority of the participants (60.7%) were female. The mortality rate was 61.4%. The median age at death was 25.5 years (IQR; 21-34). Smoking history [p=<0.001], presence of respiratory disease and cardiovascular disease [p=0.002] were significantly associated with higher mortality. Having an income level