Prevalence, determinants, and management of chronic kidney disease in Karachi, Pakistan - a community based cross-sectional study

BACKGROUND Chronic kidney disease (CKD) is increasing being recognized as a global public health problem. However, there is dearth of information on the prevalence, determinants, and management of CKD from low- and middle-income countries. The objectives of the study were to determine the 1) prevalence of CKD; 2) socio-demographic and clinical factors associated with CKD; and 3) the existing management of these patients with regards to blood pressure control, and use of antihypertensive medications. METHODS We conducted a cross-sectional study on 2873 participants aged ≥ 40 years in 12 representative communities in Karachi, Pakistan. The primary outcome was clinically significant CKD defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 estimated by CKD-EPI (CKD Epidemiology Collaboration) Pakistan equation (0.686 × CKD-EPI1.059) or urinary albumin to creatinine ratio ≥ 3 mg/mmol (i.e. KDOQI CKD stage G3, A2 or worse). RESULTS The overall prevalence (95% CI) of CKD was 12.5% (11.4 - 13.8%). The factors independently associated with CKD were older age, hypertension, diabetes, elevated systolic blood pressure, raised fasting plasma glucose, raised triglycerides, and history of stroke (p<0.05 for each). About 267 (74.4%, 69.5 - 78.8%) adults with CKD had concomitant hypertension. Of these, 130 (48.7%, 42.6 - 54.9%) were on antihypertensive medications, and less than 20% had their BP controlled to conventional target of ≤ 140/90 mm Hg, and only 16.9% (12.6 - 21.9%) were on blockers of renin-angiotensin system alone or in combination with other drugs. CONCLUSIONS Clinically significant CKD is common among Pakistani adults. The conventional risk factors for CKD and poor control of blood pressure among patients with CKD highlight the need to integrate CKD prevention and management in the primary care infrastructure in Pakistan, and possibly neighbouring countries.