Nonthyroidal illness syndrome in severe chronic obstructive pulmonary disease exacerbations in the elderly

Introduction: Aging is often associated with decreased serum triiodothyronine levels. There is growing evidence that critical illness can cause thyroid dysfunction and nonthyroidal illness syndrome. Elderly patients with severe chronic obstructive pulmonary disease exacerbations may be more prone to thyroid function impairment. We evaluated nonthyroidal illness syndrome incidence in elderly patients with chronic obstructive pulmonary disease during severe exacerbations and the possible impact on short-term prognosis. Materials and Method: Elderly patients (≥65 years) admitted with a diagnosis of acute respiratory failure due to an acute exacerbation were included in the study. All patients were evaluated for thyroid function and its relationship with clinical outcomes. Results: Forty-four patients with a median age of 71.5 years were included. Nonthyroidal illness syndrome incidence was 65.9% (n = 29) and it was related with increased noninvasive ventilation failure rate (p=0.04). Compared with survivors, nonsurvivors had lower triiodothyronine levels (p=0.02). Only the Glasgow coma score and noninvasive ventilation failure were found to be independent predictors of hospital mortality in logistic regression analysis. Conclusion: In this study, nonthyroidal illness syndrome was found to be relatively common in elderly patients with chronic obstructive pulmonary disease having severe exacerbations. The presence of nonthyroidal illness syndrome in these high-risk patients may affect response to treatment, and eventually, outcomes.