Thyroid dysfunction and dyslipidemia in chronic kidney disease patients

BACKGROUND Chronic kidney disease (CKD) is becoming a serious health problem; the number of people with impaired renal function is rapidly rising. Progression of CKD is associated with having a number of complications, including thyroid dysfunction, dyslipidemia and cardiovascular diseases. This study was conducted to investigate thyroid function and lipid profile in CKD patients. METHODS A cross-sectional study was conducted among 360 chronic kidney disease patients at B P Koirala Institute of Health Sciences, Dharan, Nepal. Demographic features (age and sex) and medical history of diabetes mellitus, hypertension and cardiovascular diseases of each patient were noted, and blood samples (5 ml) were analyzed for serum urea, creatinine, glucose, free triiodothyronine (T3), free thyroxine (T4), thyroid stimulating hormone (TSH), total cholesterol, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol and triglyceride. RESULTS Thyroid dysfunction was found in 38.6 % CKD patients, the most common being subclinical hypothyroidism (27.2 %), followed by overt hypothyroidism (8.1 %) and subclinical hyperthyroidism (3.3 %). Hypercholesterolemia, low HDL cholesterol, undesirable LDL cholesterol and hypertriglyceridemia were observed in 34.4, 34.1, 35 and 36.6 % patients respectively. Stage 4 and 5 CKD patients had significantly higher risk of having thyroid dysfunction as compared to stage 3 patients. Significant risk factors for cardiovascular disease in CKD patients included presence of diabetes mellitus, hypercholesterolemia, undesirable LDL cholesterol and being in stage 4 and 5 (as compared to stage 3). CONCLUSIONS Thyroid dysfunction, hypercholesterolemia, low HDL cholesterol, undesirable LDL cholesterol and hypertriglyceridemia are common in CKD patients. Progression of CKD is accompanied by rise in hypothyroidism and cardiovascular disease.