Impaired sensitivity to thyroid hormones is associated with all-cause and cause-specific mortality among chronic kidney disease patients: results from National Health and Nutrition Examination Survey (NHANES) 2007-2012.

BACKGROUND: Resistance to thyroid hormone shows underlying mechanical link with chronic kidney disease (CKD) and is prevalent in CKD population. However, whether it attributes to mortality risk among CKD population is unknown. This study aimed to examine the association of thyroid hormone resistance (THR) with all-cause and cause-specific mortality among CKD individuals. METHODS: This study extracted CKD population from the National Health and Nutrition Examination Survey (NHANES) 2007-2012. Death outcomes were ascertained by linkage to National Death Index records through 31 December 2019. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence interval (CI) for mortality from all causes, cardiovascular disease (CVD). RESULTS: A total of 1,634 adults with CKD were included in the cohort, in which 663 deaths were recorded during an average follow-up of 8.72 years. After multivariate adjustment, resistance to thyroid hormone was significantly associated with higher all-cause and CVD mortality. There was an 18% and 31% increase in risks of all-cause and CVD mortality per-standard deviation (SD) increment in Parametric Thyroid Feedback Quantile-based Index (PTFQI) respectively. When PTFQI was analyzed as categorical variable (classified according to PTFQI percentiles), after adjusted for potential confounders and taking PTFQI ≤ P(5) as reference, the HRs and 95% CIs in category with PTFQI > P(95) for all-cause mortality and CVD mortality were 2.12 [1.10, 4.09] (p for trend 0.026) and 5.14 [1.81, 14.60] for (p for trend 0.018), respectively. CONCLUSIONS: Resistance to thyroid hormone, centered on variations in the typical pituitary response to thyroid hormones, may independently correlate with all-cause and CVD mortality in CKD patients.