Abnormal thyroid function tests are frequently observed in patients of chronic kidney disease. Kidneys plays a significant role in thyroid hormone metabolism by conversion of T4 to T3 (the active metabolite). Low plasma free T3 in ESRD is a marker of the inflammation and endothelial activation and is known to predict all cause mortality.
Aim & objective of the study: The present study was done look for the biochemical abnormalities of thyroid function tests in chronic Kidney Disease and to correlate the severity of CKD and alterations of thyroid indices.
Methods: In a cross-sectional study, thyroid function test [TT3, TT4, FT3, FT4, TSH] were estimated by CLIA in 60 patients of chronic Kidney Disease who were in various stages. Symptoms of hypothyroidism, thyroid hormone abnormalities and chronic renal failure patients with different CKD stage were analyzed using Chi square test and ANOVA tests.
Results: Among the mean age was 54.2 ± 12.5 years of which 45 were male and 15 females. The mean value of TT3 in CRF stage 3, 4, 5 were 110.6 ± 17.8; 94.9 ± 29.4; 77.9 ± 29.5 ng/mL respectively (p= 0.02 Significant). The mean value of FT3 in CRF stage 3, 4, 5 were 2.52 ± 0.31; 2.08 ± 0.54; 1.89 ± 0.61 pg/mL respectively (p=0.03 Significant). The mean value of TT4 in CRF stage 3, 4, 5 were 6.47 ± 0.67; 5.12 ± 1.16; 4.41 ± 1.52 µg/dL respectively (p=0.0 significant). The mean value of FT3 in CRF stage 3, 4, 5 were 1.19 ± 0.15; 1.02 ± 0.22; 0.98 ± 0.21 pg/dL respectively (p=0.07 Not significant).
Conclusions: Total T3, total T4 and free T3 were found to be progressively decreased as stage of CKD increased. There was no significant correlation between FT4 and CKD stage. There was a significant correlation between the prevalence of thyroid dysfunction and the stage of chronic kidney disease. Higher the degree of renal insufficiency, the higher was the prevalence of thyroid hormone abnormalities, the levels of thyroid profile i.e T3, T4 decreases and TSH increases as severity of renal failure increases. Thyroid hormone abnormalities could represent a risk factor for cardiovascular disease and might also be implicated in kidney disease progression.