Relationships of Chronic Kidney Disease and Thyroid Dysfunction in Non-Dialysis Patients: A Pilot Study

Patients with chronic kidney disease (CKD) usually manifest with disorder of thyroid hormone; however, the correlation is unknown.

The study was designed to explore the relationships between CKD and thyroid dysfunction.

A total number of 905 non-dialysis participants were collected at Nanjing First Hospital from August 2009 to October 2012 according to the case records system. Patients were grouped via the estimated glomerular filtration rate (eGFR) according to the KDIGO guideline. Levels of thyroid hormone and biomarkers in different CKD groups were compared by ANOVA. Prevalence of different thyroid diseases was calculated by χ2 test.

We found that FT3 or T3 became more prevalent with increasing eGFR with the lowest level in CKD5 (p < 0.01). No significant differences were found between groups in FT4, T4, or TSH (p > 0.05). Frequency of euthyroid sick syndrome (ESS) in CKD groups was high, especially in CKD stage 5 (69.1%, p < 0.01). eGFR had positive correlation with T3 and FT3 (r = 0.239, p = 0.0001; r = 0.292, p = 0.0001). ESS had correlations with prealbumin, β2-microglobin, eGFR, and C-reactive protein (r = 0.095, p = 0.004; r = -0.12, p = 0.001; r = 0.091, p = 0.007; r = -0.096, p = 0.008; r = 0.154, p = 0.001). After adjustment for prealbumin, uric acid, HbA1c, age, gender, eGFR, and β2-microglobin, binary regression revealed that hemoglobin, C-reactive protein, and albumin were independent influence factors of ESS (p = 0.016, r = 1.014; p = 0.023, r = 1.007; p = 0.029, r = 0.996).

CKD patients have a high morbidity of ESS, mainly low T3 syndrome. Anemia, inflammation, and malnutrition may contribute to ESS in CKD.