Association Between Blood Pressure, Glomerular Filtration Rate, and Serum Thyroid-Stimulating Hormone Levels in Hypothyroid Patients: A Retrospective Single-Center Study

Background: Thyroid hormones have substantial effects on blood pressure (BP) and renal function as they influence the glomerular filtration rate (GFR). Maintaining healthy BP and preventing premature development of nephropathy necessitates taking steps. Objectives: The aim of this study was to explore the association between BP, GFR, and thyroid-stimulating hormone (TSH) levels in hypothyroid patients at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. Methods: A retrospective record review study of all hypothyroid patients from June 1, 2010 to June 6, 2020. The medical records of 1,181 adult patients were reviewed, and 157 met the criteria. All patients aged >18 years who were diagnosed with hypothyroidism and were on levothyroxine therapy, were included in this study. Results: More than half of the participants were female (83.4%). There was no significant correlation between TSH and systolic BP (P= 0.6), or TSH and diastolic BP (P=0.8), while there was a positive correlation between TSH and creatinine (r=0.4, P=0.001) and a negative correlation between TSH and GFR (r=−0.2, P=0.01). Conclusions: We found no association between BP and TSH, while creatinine correlated directly and GFR inversely with TSH. Follow-up renal function should be a target for physicians in hypothyroid patients to prevent premature complications.