Early age at natural menopause is related to lower post-bronchodilator lung function: A longitudinal population-based study

Rationale: Poor lung function, a significant predictor of mortality, has been observed in postmenopausal women compared with those still menstruating. Menopausal age is a risk factor for several adverse health outcomes, but little evidence exists on the impact of menopausal age on lung function impairments, especially regarding post-bronchodilator lung function measures.

Objectives: To investigate the association between age at menopause and pre- and post-bronchodilator lung function outcomes.

Methods: During the sixth-decade follow-up of the Tasmanian Longitudinal Health Study cohort (mean age, 53 yr), information was collected on most recent menstrual period and menopausal status. Lung function was measured at age 7 years and again at 53 years. Multiple linear regression was performed to determine the association between age at menopause and pre- and post-bronchodilator spirometry, controlling for early and adult life confounders.

Results: Women reporting an early age at natural menopause (<45 yr) had lower post-bronchodilator forced expiratory volume in 1 second (-168 ml; 95% confidence interval, -273 to -63) and lower forced vital capacity (-186 ml; 95% confidence interval, -302 to -70) than postmenopausal women who experienced menopause at a later age (≥45 yr). No association was observed with forced expiratory volume in 1 second/forced vital capacity ratio. Adjustment for early-life confounders strengthened these associations.

Conclusions: This study provides new evidence that early menopause is associated with reduced lung function that is suggestive of restriction, but not obstruction, even after adjustment for early-life confounders. Given the important link between poor lung function and mortality, clinicians should be aware of the risk of diminished lung function in postmenopausal women who experience menopause at an early age.