Serum thyroid-stimulating hormone levels are not associated with exercise capacity and lung function parameters in...

Area of Science:

• Endocrinology
• Cardiorespiratory Physiology
• Public Health

Background:

• Thyroid dysfunction is linked to cardiovascular issues, potentially impacting cardiorespiratory function and exercise capacity.
• Previous research on thyroid dysfunction and exercise capacity is limited by small sample sizes.
• Investigating this association in a general population is crucial.

Purpose of the Study:

• To examine the relationship between serum thyroid-stimulating hormone (TSH) levels and lung function.
• To assess the association of TSH levels with cardiopulmonary exercise testing (CPET) parameters.
• To clarify the impact of thyroid function on exercise capacity in the general population.

Main Methods:

• Pooled data from two large, independent, population-based studies (SHIP and SHIP-Trend-0) involving 4206 participants.
• Thyroid function assessed via serum TSH levels; lung function measured by FEV1 and FVC.
• Cardiopulmonary exercise testing (CPET) performed using a modified Jones protocol; analyses adjusted for multiple covariates.

Main Results:

• Serum TSH levels, analyzed both continuously and categorically, showed no consistent association with lung function parameters.
• No significant association was found between serum TSH levels and key cardiopulmonary exercise testing (CPET) metrics.
• These findings held true across different categorizations of TSH levels, including clinical cut-offs and quintiles.

Conclusions:

• Thyroid dysfunction, as indicated by TSH levels, is not significantly associated with lung function in the general population.
• Cardiopulmonary exercise capacity does not appear to be influenced by thyroid dysfunction in this population.
• The study suggests thyroid function may not be a primary determinant of lung function or exercise capacity in community-dwelling individuals.