Correlation Between Albuminuria and Thyroid Function in Patients with Chronic Kidney Disease

Introduction: Decreased renal function is a significant public health issue, increasing the risk of various adverse outcomes.Thus, identifying potentially modifiable factors associated with the onset of chronic kidney disease (CKD) is imperative.Although CKD has been demonstrated to impact thyroid function through various mechanisms; there remains insufficient and contentious data regarding the association between albuminuria and thyroid function in patients diagnosed with CKD.This study aimed to elucidate the association between albuminuria and thyroid function tests in patients with CKD.Methods: We conducted a cross-sectional analysis involving 232 patients with CKD.Patients were categorized on the basis of albuminuria levels, measured by the urinary albumin/creatinine ratio (ACR), following the KDIGO 2012 criteria: ACR1 <30 mg/gr, ACR2 30-300 mg/gr, and ACR3 >300 mg/gr.Thyroid stimulating hormone (TSH), free thyroxine (free T4), and free triiodothyronine (free T3) levels were measured to assess thyroid function. Results:The ACR among subjects ranged from 1.0 mg/g to 10260.0 mg/g, with a mean urinary ACR of 485.7±1250.9mg/g.Among the patients, 47.4% (n=110) had an ACR <30 mg/g, 25.4% (n=59) had an ACR 30-300 mg/g was, and 27.1% (n=63) had an ACR >300 mg/g.TSH levels ranged from 0.3 to 14 mU/L, free T3 ranged between 0.6 and 4.8 ng/L, and free T4 ranged from 5.5 to 17.8 ng/L.No significant differences were observed in TSH, free T4, and free T3 values among the ACR1, ACR2, and ACR3 groups (p>0.05).A significant positive correlation was found between glomerular filtration rate and free T3 (r=0.395,p<0.05), whereas a significant negative correlation was noted between ACR and free T3 (r=-0.264,p<0.05). Conclusion:Our findings suggest that albuminuria may contribute to a reduction in free T3 levels in patients with CKD.However, it is crucial for physicians to recognize that CKD patients with elevated albuminuria levels may exhibit abnormal thyroid function.