Free triiodothyronine in sera of acutely III general medical patients: A prognostic indicator?

Abstract

We measured free triiodothyronine (FT3), thyrotropin (TSH), and C-reactive protein (CRP) in sera of 39 acutely ill medical patients who died within three months of admission and 39 age- and sex-matched control patients selected at random from a total of 294 acute medical admissions. Serum FT3 in nonsurvivors (1.91 ± 1.51 pmol/L) was significantly lower than that in survivors (3.01 ± 1.3 pmol/L, P <0.01) and the CRP in nonsurvivors (54.6 ± 59.2 mg/L) was significantly higher than in survivors (43.6 ± 59.5 mg/L, P <0.05). There was no difference in plasma TSH between the two groups. The estimated odds ratio relating death to a plasma FT3 value <1.0 pmol/L on admission was 17 (highly significant: P <0.001). We conclude that plasma FT3 may be a useful prognostic indicator in acutely ill patients.