The burden of comorbidity and the C‐reactive protein levels in nonthyroidal illness syndrome with metabolic syndrome and atherosclerosis‐related cardiovascular complications

Abstract

Thyroid hormones undergo significant modifications during severe illnesses, and the low T3 levels are the hallmark of nonthyoidal illness syndrome (NTIS), due to a reduced extrathyroidal conversion from T4. We examined 41 patients with NTIS by a modified cumulative illness rating scale (CIRS) and the measurement of FT3, FT4, TSH, and C-reactive protein (CRP) levels. Fifty-seven control subjects were enrolled. We observed reduced FT3 and increased FT4 levels in NTIS patients (P < 0.05). The CIRS scores (severity and comordity index) were inversely related to FT3 and positively related to FT4 levels (P < 0.05). The CRP and the FT4 concentrations were positively associated (P < 0.01). Our study showed that the reduced FT3 and increased FT4 levels were significantly related to the comorbidity and severity of systemic illnesses, probably as a result of impairment in the peripheral hormonal conversion. The CIRS scale and the CRP are useful tools for a better evaluation of these patients.