[The effect of age on in vitro thyroid function tests in adult patients on a chronic hemodialysis program]

The research was designed to investigate in vitro thyroid function tests (TT4, TT3, FT4, FT3, rT3 and TBG) in 14 patients on regular haemodialysis (RHD) and 15 healthy, euthyroid subjects aged 40-59 years and in 17 patients on RHD and 14 subjects aged 60 years and more. Group of older subjects had significantly lower (p less than or equal to 0.01) levels of TT4, TT3 and TBG than group of younger, but those differences were lost between patient groups. Group of older patients had significantly lower level of FT3 than group of younger. Both groups of patients had significantly lower levels of TT3, FT4 and FT3 than both control groups and there was no significant difference in rT3 levels. Age structure markedly influenced difference in TT4 levels and there was also some influence on TBG level. Serum TT4 concentration was significantly lower in both patient groups than in younger subjects group but similar to the level in group of older subjects. The only difference in TBG levels between four groups was significantly lower (p less than or equal to 0.05) TBG level in group of younger patients than in group of younger subjects.