Prevalence of anemia and cardiovascular diseases in chronic kidney disease patients: a single tertiary care centre study

Abstract

Background: Chronic kidney disease (CKD) is recognized as a global health issue having high mortality and morbidity rates putting a substantial burden on global resources. CKD has become a recognised independent risk factor for several adverse health outcomes including cardiovascular disease (CVD). Anaemia is an anticipated consequence as renal function declines, and can develop at any stage of CKD. There is a strong association between anemia and cardiovascular complications in CKD patients and many studies have proven that anemia plays a key role in worsening CVD in CKD patients. The objective of this study was to study the prevalence of anemia and cardiovascular diseases in CKD patients and establish an association between them.Methods: This study was conducted between January 2008 and June 2008 for a period of six months at a Government tertiary referral institution in south India. During this period, all newly diagnosed cases of chronic kidney disease based on the National Kidney foundation definition were included in this study. All the patients were evaluated based on detailed history taking, clinical examination and laboratory investigations after an informed consent was obtained from them. Staging of CKD was done based on the national kidney foundation (NKF/KDIGO) staging system. GFR was estimated using the abbreviated MDRD (Modification of Diet in Renal Disease) formula.Results: Of the 333 newly diagnosed CKD patients, a large majority (264, 79.28%) of the patients in the study presented in stage 5 CKD. The mean Hb in the study was 8.42±2.20 g/dl. Anemia was present in 90.39% while 25.53% had an Hb of <7g/dl. The prevalence of anemia increased from stage 3 (66.6%) to stage 5 (94.7%) and this correlation was statistically significant (p<0.0005). 167 (50.15% ) were found to have some form of cardiovascular disease, of which 120 (71.86%) were males and 47 (28.14%) were females. 83.93% had left ventricular hypertrophy, 16.17% had ischemic heart disease and 7.78% had congestive heart failure. 56.3% of patients in the age group 41-60 years had cardiovascular disease. The correlation between cardiovascular disease and age was statistically significant (p = 0.04139). And it was found that cardiovascular disease was more common when the cause of CKD was Diabetic nephropathy (65.8%) and hypertensive nephrosclerosis (84.6%). The correlation between the cardiovascular disease and etiological diagnosis of CKD was statistically significant. (p<0.0005).Cardiovascular disease was present in 61.2 % of the study population with diabetes mellitus and in 56.4% of the study population with hypertension. The correlations between CVD and diabetes and hypertension were statistically significant. Cardiovascular disease was present in 61.2% of the study population with Hemoglobin <7 gm/dl, 41.7% with Hb between 7-11 gm/dl and the correlation between cardiovascular disease and the level of Hb was highly significant in CKD patients.Conclusions: Thus there is a strong association between the clinical trial of anemia, CKD and CVD and prompt identification and management of common risk factors and adequate correction of anemia is necessary to slow progression of CKD and prevent cardiovascular events.