Thyroid Dysfunction in Patients with Chronic Kidney Disease: A Single-Centre Observational Study in The North Coastal Region of Andhra Pradesh

Background: Chronic Kidney Disease (CKD) is associated with several endocrine abnormalities, among which thyroid dysfunction is one of the most common yet underrecognized complications. Alterations in thyroid hormone metabolism occur due to impaired renal function, leading to abnormalities such as low triiodothyronine (T3) syndrome, subclinical hypothyroidism, and overt hypothyroidism. Early identification of these abnormalities may improve the clinical management of CKD patients. The objective is to determine the prevalence and pattern of thyroid dysfunction among patients with CKD and to assess the relationship between thyroid hormone abnormalities and the severity of renal dysfunction. Material and Methods: This hospital-based, single-centre observational cross-sectional study was conducted among 250 patients with CKD attending a tertiary care hospital in the North Coastal region of Andhra Pradesh. Demographic, clinical, and laboratory data were collected. Thyroid function tests including serum T3, T4, and thyroid stimulating hormone (TSH) were measured using chemiluminescent immunoassay. CKD staging was performed according to KDIGO guidelines using estimated glomerular filtration rate (eGFR). Statistical analysis was performed using SPSS version 26.0, and a p-value <0.05 was considered statistically significant. Results: Among the 250 study participants, 148 (59.2%) were males and 102 (40.8%) were females, with a mean age of 56.8 ± 14.2 years. Thyroid dysfunction was observed in 106 (42.4%) patients. Low T3 syndrome was the most common abnormality, affecting 61 (24.4%) patients, followed by subclinical hypothyroidism in 28 (11.2%) and overt hypothyroidism in 13 (5.2%) patients. A significant association was observed between declining renal function and low serum T3 levels (p<0.001). Serum T3 demonstrated a moderate positive correlation with eGFR (r=0.482, p<0.001). Conclusion: Thyroid dysfunction is highly prevalent among CKD patients, with low T3 syndrome being the most common abnormality. The prevalence of thyroid dysfunction increases with advancing CKD stage. Routine thyroid function assessment should be considered in CKD patients for early detection and appropriate management of thyroid abnormalities.

Keywords: Chronic Kidney Disease, Thyroid Dysfunction, Low T3 Syndrome, Hypothyroidism, eGFR, TSH, CKD, Thyroid Hormones.