SUBCLINICAL HYPOTHYRIDISM IN PATIENTS WITH CHRONIC KIDNEY DISEASE VISITING AT TERTIARY CARE HOSPITAL, KARACHI

Objective: To determine frequency of sub-clinical hypothyroidism in chronic disease patients. Patients and Methods: A cross sectional study conducted through non-probability purposive sampling from March to September 2010 in the Department of nephrology at Jinnah Postgraduate Medical College (JPMC), Karachi. Total 158 patients aged ≥18years with stage 3 to 5 chronic kidney who not on maintenance hemodialysis were included and patients with history of thyroid surgery, known thyroid disease and on treatment or neck radiation were excluded. Chronic kidney disease defined as lower glomerular filtration rate (stage III 30-59ml/min/1.73m2), stage IV (15-29 ml/min/1.73m2) and stage V (<15 ml/min/1.73m2). Sub-clinical hypothyroidism was defined as elevated thyroid stimulating hormone (TSH) level >4.05mIU/dl and normal thyroxine (T4) level (0.89-1.79ng/dl). Results: Mean age was 50.63 (range 19-85years), 76 (48%) were males and 82 (52%) were females. Sub-clinical hypothyroidism was found in 31 (20%) patients among patients with chronic kidney disease. Out of these, 16 patients (52%) were females and 15 (48%) were males (p=0.565). Most patients (52%) were aged between 45--59 years followed by 25% in ≥60yr and 23 % in aged 18-44years (p=0.371). Among severity of CKD patients; sub-clinical hypothyroidism was found in 38% in stage III CKD, 36% in stage IV CKD and 26% in stage V CKD (p=0.962). Among duration of CKD; sub-clinical hypothyroidism was found in 58% with less than 1year of CKD, followed by 39% between 1-2years and 03% of more than 2 years of CKD (p=0.107). Conclusion: Sub-clinical hypothyroidism is a common problem among patients with CKD and found in 20% of patients. SCH found in younger age group 45--59years and in patients with stage III and IV CKD. Key Words: Sub-clinical hypothyroidism, Chronic Kidney Disease, Glomerular filtration rate