Is bronchial asthma a risk factor for chronic kidney disease?

Abstract

Introduction Bronchial asthma is a chronic, inflammatory lung disease with exacerbations. Patients with asthma have higher risks of coronary heart disease, diabetes mellitus, and hypertension, although the impact of asthma on other vital organs is not yet verified. Chronic kidney disease (CKD) is a major global problem. In addition to well-known risk factors of CKD, there might be other previously underestimated or unrecognized risk factors that are not yet discovered. Aim The aim of this study was to determine the frequency and factors associated with CKD among asthmatic patients. Patients and methods An analytical, cross-sectional study was conducted on 118 patients known to have bronchial asthma and 118 healthy individuals; all of them were subjected to spirometry. Glomerular filtration rate (GFR) was estimated using the Modification of Diet in Renal Disease study group equation. Results Development of CKD was significantly higher among asthmatic patients than in healthy individuals (17.4 vs. 0.8%, respectively). GFR was higher in the well-controlled asthmatic group than in the uncontrolled group (96.3±18.1 vs. 90.1±20.3), but this difference was statistically insignificant. Occurrence of CKD was significantly higher among those with asthma for 20 years or longer than those with asthma for less than 20 years (45.5 vs. 2.4%, respectively). GFR was negatively correlated to age, BMI, and disease duration with high statistical significance, and was positively correlated with all parameters of pulmonary function test (FVC%, FEV1%, FEV1/FVC, and PEFR%) and partial O2 pressure with high statistical significance. Significant predictors for the development of CKD among asthmatic patients were longer disease duration and higher BMI. However, high partial O2 pressure was protective for the development of CKD. Conclusion Bronchial asthma can be associated with CKD. Prolonged disease duration and higher BMI were the most common predictors for the development of CKD.