Thyroid Hormone Profiles in Patients With Chronic Kidney Disease at Kenyatta National Hospital

Abstract

Chronic Kidney Disease (CKD) is a disease spectrum characterized by progressive loss of renal function over a period of time. It has reached epidemic proportion in many countries with an incidence of approximately 11% among the adult population in the United States of America. There is no local data on CKD prevalence, however regionally a study done in Nigeria reports a prevalence of 12.4%. Early identification and management of CKD·has been shown to reduce the adverse outcomes which include kidney failure and cardiovascular disease. Thyroid dysfunction including hypothyroidism, hyperthyroidism and non-thyroidal illness has been reported in CKD patients. Non thyroidal illness or low T3 syndrome has been shown to worsen CKD by increasing cardiovascular morbidity and mortality and has been reported as an independent predictor of the cardiovascular mortality in these CKD patients. There is need to determine the thyroid hormone profiles in these CKD patients and thus prevent the adverse outcomes . . The study determined the thyroid hormone profiles in patients with chronic kidney disease at Kenyatta National Hospital. Descriptive cross-sectional study The study was conducted at the Renal Clinic at Kenyatta National Hospital, a tertiary and referral hospital in Nairobi, Kenya. Patients with chronic kidney disease who attended the renal clinic. Methods: A total of 137 study participants with CKD were recruited. Demographic and medical data were obtained from the participants using a questionnaire designed for this study. Estimation of glomerular filtration rate was done using the 4 variable Modification of Diet in Renal Disease (MDRD) formula with subsequent staging of chronic kidney disease. Thyroid Stimulating Hormone (TSH), Total Thyroxine (T4), Total Triiodothyronine (T3), Free triiodothyronine (fT3), and Free Thyroxine (fT4) were estimated using enzyme immunoassay on these patients with CKD. nata management: The data obtained included demographics, CKD stage and hormone Jevels. These were entered and analyzed using Epidata program version 3.1.

A total of 137 participants were recruited into the study. Eighty three (60.6%) of these were males and 54 (39.4%) were females. Majority of the participants 56 (40.9%) were in stage 4 ofCKD and only 2 (1.5%) were in stage 2. Forty one (29.9%) and 38 (27.7%) were in CKD stage 3 and stage 5 respectively. There were no participants in CKD stage 0 and 1 recruited. Diabetes mellitus and hypertension were the main primary disease processes leading to CKD. Majority of the participants (58%) were euthyroid, while 42% had abnormal thyroid results; of these, 13.9% had non-thyroidal illness and 15.3% and 12.4% had hypothyroidism and hyperthyroidism respectively. The difference in mean duration of CKD amongst the thyroid hormone categories was not statistically significant (p=0.345). The proportion of patients with non-thyroidal illness increased with increasing severity of CKD. This was statistically significant (P = 0.0004). In this study, abnormalities in the thyroid profile were found in 42% of the participants. The most common thyroid derangement was isolated low T3 values. Nonthyroidal illness was shown to increase with increased severity ofCKD. As the CKD patients in KNH have deranged thyroid profiles, regular thyroid hormone assays should be incorporated in their follow up. Prevalence of hyperthyroidism is higher in this study than reported in other literature. There is need to assay thyroid hormone profiles in patients with CKD stage 3 and above. Studies on thyroid hormone profile on lower CKD stages should also be done. There is need for further studies to evaluate the relationship between hyperthyroidism and CKD in Kenya.