Exercise performance in young and middle-aged female patients with subclinical hyperthyroidism
Renata Boschi Portella1, Jefferson Luiz da Costa Silva, Márcia Branco Wagman
1Endocrine Clinic, University Hospital Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. portella@novanet.com.br
Thyroid : Official Journal of the American Thyroid Association
|August 17, 2006
Summary
Subclinical hyperthyroidism (SH) did not significantly impact exercise capacity in women. Treadmill tests showed no difference in oxygen consumption or anaerobic threshold between SH patients and controls.
Area of Science:
- Endocrinology
- Cardiovascular Physiology
- Sports Medicine
Background:
- Subclinical hyperthyroidism (SH) is associated with cardiovascular changes.
- Exercise performance may be impaired in individuals with SH.
Purpose of the Study:
- To evaluate the cardiopulmonary response to treadmill testing in patients with exogenous subclinical hyperthyroidism.
- To assess the impact of SH on exercise capacity in women.
Main Methods:
- 14 female patients with exogenous SH and 15 healthy euthyroid women underwent treadmill cardiopulmonary testing using the Balke protocol.
- Measurements included gas exchange (V(E), peak VO(2), peak VCO(2)), anaerobic threshold (AT), and electrocardiogram (ECG).
- Resting heart rate was higher in the SH group.
Main Results:
- No significant differences were observed between groups in peak oxygen consumption (peak VO(2)), anaerobic threshold (AT), peak heart rate, or exercise duration.
- Resting heart rate was significantly higher in patients with SH.
- No correlation was found between peak VO(2) and thyroid hormone levels or disease duration.
Conclusions:
- Exogenous subclinical hyperthyroidism does not significantly affect exercise capacity in young and middle-aged women.
- Cardiopulmonary exercise testing reveals preserved exercise performance despite SH.
- Further research may explore long-term cardiovascular implications.
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