Prevalence of Chronic Kidney Disease among older adults in urban Sri Lanka - Tip of the iceburg?

Abstract

INTRODUCTION: Prevalence of chronic kidney disease (CKD) is increasing worldwide, mainly due to increasing diabetes mellitus (DM) and hypertension (HPT) in aging populations. Although these diseases affect many, data on population prevalence of CKD in Sri Lanka is scarce. However, a CKD of uncertain aetiology (CKDu), mainly seen in the North Central parts of the country, receives much attention. The prevalence of CKDu among adults in the affected areas was estimated to be 15.3% in 2012. Our objectives were to identify the prevalence of CKD in an urban adult Sri Lankan population and compare that to the prevalence of CKDu. METHODS: Subjects were randomly selected from the Ragama Health Study (RHS), an on-going community based research project of the Ragama Medical Officer of Health area with 3012 adult participants. Data was obtained using an interviewer-administered questionnaire. Serum creatinine was tested and estimated glomerular filtration rate (eGFR) was calculated using the CKD-EPI formula. CKD was defined as eGFR <60 ml/min/1.73m2, using the KDIGO/KDOQI classifications. RESULTS: Of 301 participants with a mean age of 57.5 years (range 40-73 years), 178/301 (59.1%) were female. 43/301 had eGFR <60 ml/min/1.73m2, giving a CKD prevalence of 14.3% in our sample. 34/43 (79.1%) were in CKD Stage IIIA. 5/43 (11.6%) had only DM, 14/43 (32.6%) had only HPT and 13/43 (30.2%) had both DM and HPT, as probable aetiological factors for CKD. A cause of CKD could not be readily identified in 11/43 (25.6%). Patients with CKD were significantly older than 60 years (p<0.000), and were more likely to have DM (p<0.012), HPT (p<0.000), coronary artery disease (p<0.031) and hyperlipidemia (p<0.0230), compared to those without CKD. CONCLUSIONS: CKD prevalence in our sample was similar to the prevalence of CKDu in North Central Sri Lanka. As expected, DM and HPT were the primary associated co-morbidities. Most CKD patients were in stage IIIA, where early recognition and better control of co-morbidities are known to retard progression. CKD of known aetiology is under-recognized in Sri Lanka, and is probably as significant a problem as CKDu. Large population-based studies are needed to better understand the actual size of the problem.