Seasonal variation in Hospitalisation for Respiratory Diseases in the Tropical Rain forest of South Western Nigeria

Abstract

The objective of this study was to determine the seasonal variation in hospitalisation for respiratory disease in a tertiary care centre in the tropical rain forest zone of South Western Nigeria. A retrospective analysis was performed to the determine the seasonal variation of respiratory diseases hospitalised in Federal Medical Centre in Ido-Ekiti, Nigeria from November, 2006 to October 2009. Data were extracted from the medical records of hospitalized patients who had acute exacerbation of chronic obstructive pulmonary disease (COPD), asthma, pneumonia and pulmonary tuberculosis (PTB). Two hundred and thirty three patients aged ≥ 15 years hospitalised for respiratory diseases were analysed, 68(29.2%) had PTB, 66(28.3%) had pneumonia, and 61(26.2%) had asthma while 38(16.3%) people had COPD. The mean age of the patients was 47.8 19.6 years. Monthly mean of hospitalisation for pneumonia (8.00 vs.3.86; p=<O. 001) and acute exacerbation of chronic obstructive pulmonary disease (4.60 vs.2.50; p=O.004) were significantly higher in dry season, while that of asthma (5.29 vs.4.80; p=0.338) and pulmonary tuberculosis (5.71 vs.5.60; p=0.898) were higher in the rainy (wet) season, although seasonality of asthma and PTB was less pronounced and not significant. The hospitalisation of asthma and pulmonary tuberculosis were higher during the rainy (wet) season while pneumonia and acute exacerbation of COPD were higher during the dry season. The outcome of this study may help to identify seasonal disease-modifying factors associated with hospitalisation of respiratory diseases. Furthermore, identifications of these variations are important for efficient allocation of health-care resources based on seasonal hospitalisation trend.