OBJECTIVES: In this study, we explore the associations of decreased thyroid 
hormone levels with inflammation, wasting and survival in biochemically 
euthyroid patients with end-stage renal disease (ESRD).
DESIGN: After exclusion of 23 patients with thyroid-stimulating hormone (TSH) 
values outside the normal range (0.1-4.5 mIU L(-1)), 187 clinically and 
biochemically euthyroid incident ESRD stage 5 patients starting dialysis were 
followed for a median of 20 (range 1-60) months. Measurements of total and free 
forms of thyroid hormones, s-albumin, hs-CRP, interleukin (IL)-6, vascular 
adhesion molecule (VCAM)-1 and insulin-like growth factor 1 (IGF-1) were 
performed at baseline.
RESULTS: In this population, 17 out of 210 patients (8%) were defined as 
subclinically hypothyroid. Multivariate analysis, according to receiver 
operating characteristic (ROC) curves, showed that mortality was best predicted 
by total triiodothyronine (T3). When using the cut-off levels derived from ROC, 
low T3 levels were associated with increased inflammation (higher hs-CRP, IL-6 
and VCAM-1) and lower concentration of both s-albumin and IGF-1. Finally, low T3 
but not low free triiodothyronine was associated with worse all-cause 
(Likelihood ratio = 45.4; P < 0.0001) and cardiovascular mortality (Likelihood 
ratio = 47.8; P < 0.0001) after adjustment for confounding factors.
CONCLUSION: This study showed that low T3 levels are independent predictors of 
all-cause and also cardiovascular disease mortality in biochemically euthyroid 
patients, perhaps due to an intimate association with inflammation. Based on 
these results, the use of T3 levels in studies assessing the relationship 
between thyroid dysfunction and mortality risk is recommended.