Age and Ageing Advance Access published online on November 16, 2009
Age and Ageing, doi:10.1093/ageing/afp197
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Non-thyroidal illness syndrome and short-term survival in a hospitalised older population
1 Department of Internal Medicine, University of Pisa, Pisa, Italy
2 General Medicine IV Unit, Cisanello Hospital, Pisa, Italy
3 Department of Morphological and Biomedical Sciences, University of Verona, Verona, Italy
Address correspondence to: F. Monzani, Geriatric Unit, Department of Internal Medicine, University of Pisa, Pisa, Italy. Tel: +39-0509-93490; Fax: +39-0509-93585. Email: fmonzani{at}med.unipi.it
Background: non-thyroidal illness syndrome (NTIS) has been associated with an adverse clinical outcome.
Objective: to evaluate the prevalence of NTIS, its impact on patients’ survival and the possible pathogenic role of systemic inflammation.
Design: observational cross-sectional analysis.
Participants and setting: three hundred and one acutely ill older patients (156 women; median age 81 years, range 65–101) consecutively admitted to a primary care unit.
Methods: serum FT3, FT4 and thyrotropin levels as well as acute inflammation indexes were evaluated.
Results: the NTIS prevalence (specifically low T3 syndrome) was 31.9%. A significant association was found between NTIS and acute renal failure (P = 0.006), New York Heart Association classification (NYHA) IV heart failure (P = 0.003) and metastasised cancer disease (P = 0.0002). Serum FT3 values correlated inversely with serum C-reactive protein (P < 0.0001), lactate dehydrogenase (P = 0.0004), fibrinogen (P = 0.03) and erythrocyte sedimentation rate (P < 0.0001) values, and progressively decreased with increasing tertiles of age (P = 0.0004). The mortality rate was significantly higher (P = 0.0002) among patients with low T3 syndrome, which emerged as the sole predictive factor of death (odds ratio 4.3; 95% confidence interval 1.7–10.5).
Conclusions: low T3 syndrome is very common in the hospitalised older population, emerging as the most sensitive independent predictor of short-term survival. Serum FT3 determination should be included in the assessment of short-term prognosis of acutely ill older patients.
Keywords: thyroid hormones, cytokines, non-thyroidal illness syndrome (NTIS), survival, age, elderly
* Contributed equally to this study.
Received 14 April 2009; accepted in revised form 26 August 2009.