A recent study published in Renal Failure uncovered a substantial association between hypothyroidism and chronic kidney disease (CKD), highlighting the prevalence of urine protein in patients with both conditions. The investigation wanted to unravel the mechanisms linking thyroid hormones and urine proteins, providing critical insights into the complex interplay between hypothyroidism and CKD.
The study conducted from November 2016 to August 2018, included 99 Japanese CKD patients with proteinuria. Major parameters assessed here were thyroid function (serum free T3, free T4, and thyroid-stimulating hormone), kidney function (estimated glomerular filtration rate), thyroid antibodies, and albumin. The research also looked into a comprehensive urine examination, examining levels of total T3, total T4, TSH, Alb, preAlb, thyroid-binding globulin, and overall protein.

The participants were of 60 years in average, with a slight male predominance (50.5%). Notably, around 70% of the patients displayed thyroid dysfunction, with 51.5% experiencing overt or subclinical hypothyroidism, irrespective of antibody status. Also, 21.2% of patients were diagnosed with nephrotic syndrome with a significant association between hypothyroidism and this renal complication. The study found higher urinary levels of thyroid hormones in patients with nephrotic syndrome, suggesting a more severe form of hypothyroidism.
These underscore that urinary loss of thyroid hormones may be a crucial factor influencing hypothyroidism independently of autoimmune factors. This established a link between hypothyroidism and nephrotic syndrome emphasizes the need for a comprehensive understanding of thyroid-kidney interactions in clinical management.
The outcomes deepens our understanding of the intricate relationship between hypothyroidism and chronic kidney disease and also opens avenues for targeted interventions. As we look further into the complexities of these interconnected health issues, this study marks a significant stride forward in advancing personalized treatment strategies for patients grappling with both hypothyroidism and chronic kidney disease.
Source:
Yuasa, R., Muramatsu, M., Saito, A., Osuka, H., Morita, T., Hamasaki, Y., & Sakai, K. (2023). Urinary excretion of thyroid hormone in CKD patients: a proof-of-concept of nephrogenic hypothyroidism. Renal Failure, 45(2). https://doi.org/10.1080/0886022x.2023.2293224