Thyroid hormone abnormalities in euthyroid type 2 diabetes mellitus with chronic kidney disease in Saudi community based hospital

Abstract

Background and objective: The interactions between kidney and thyroid functions are known for years. The present retrospective study was conducted to find out the thyroid hormone abnormalities in patients with chronic kidney disease (CKD) and type 2 diabetes mellitus (T2DM) in Saudi community based hospital. Design: We analyzed retrospectively 872 participants with T2DM whom are between the age 20 to 96 years. All patients were from the population of the Primary health centre at King Fahad Armed Forces Hospital, Jeddah, Saudi Arabia. All data were collected on the basis of a review of electronic medical data. Participants were defined as having T2DM according to self-report, clinical reports, use of antidiabetic agents and HbA1c (≥6.5). HbA1c was expressed as percentage. High performance liquid chromatography was used. Serums FT4 were estimated by radioimmunoassay and Serum TSH was estimated by Immunoradiometric assey. All patients in the present study fulfilled the revised National Kidney Foundation criteria for the diagnosis of CKD. The total numbers of cohort were separated on basis of age values into four groups: <40 years, 40-49 years, 50-59 years and ≥60 years. Results: 872 subjects with T2DM were included. There were 273 (31.3%) male and 557 (68.7%) were female with mean age 54.5±13.0. The mean HbA1c, TSH and FT4 value were 8.1±2.2, 2.0±1.1 mIU/l and 15.8±2.8 pmol/l respectively. Among cases of T2DM and CKD, there were 239 (61.9 %) female and 147 (38.1 %) were male with female to male ration 1.6:1.0, p<0.0001. Patients with CKD were significantly older than patients without CKD, 57.3±2.9 vs. 52.3 ±12.6 respectively, p<0.0001. Patients with CKD were significantly have higher HbA1c than patients without CKD, 8.7±2.3 vs. 7.7±2.1 respectively, p<0.0001. Patients with CKD were significantly have higher TSH than patients without CKD, 2.1±1.0 vs. 1.9±1.1 respectively, p=0.001. Patients with CKD were significantly have lower FT4 than patients without CKD, 15.5±2.8 vs. 16.1±2.9 respectively, p=0.03. Patients with CKD have higher TSH than patients without CKD across all age groups. Patients with CKD have lower FT4 than patients without CKD across all age groups except patients older than 60years. Conclusion: We conclude that despite the limitations of this hospital-based retrospective study, high TSH and low FT4 levels are highly prevalent in cohort of Saudis with CKD and T2DM. The majority of our patients in our finding were predominantly females. These two observations remain to be validated by population-based studies. In the absence of registry data, larger cooperative studies involving diverse population samples from multiple centers could help to provide further information on the true thyroid hormone abnormalities.