Female reproductive history in relation to chronic obstructive pulmonary disease and lung function in UK biobank: a prospective population-based cohort study

Objectives: Sex differences in respiratory physiology and predilection for developing chronic obstructive pulmonary disease (COPD) have been documented, suggesting that female sex hormones may influence pathogenesis. We investigated whether aspects of female reproductive health might play a role in risk of COPD among women.
Design: Population-based prospective cohort study.
Setting: UK Biobank recruited across 22 centres in the United Kingdom between 2006-2010.
Primary and secondary outcomes measures: We examined a range of female reproductive health indicators in relation to risk of COPD-related hospitalisation/death (n=271 271) using Cox proportional hazards regression; and lung function (n=273 441) using linear regression.
Results: Parity >3 was associated with greater risk of COPD-related hospitalisation/death (adjusted HR 1.45; 95% CI: 1.16, 1.82) and lower FEV 1/FVC (adjusted mean difference -0.06; 95% CI: -0.07, -0.04). Any oral contraception use was associated with lower risk of COPD-related hospitalisation/death (adjusted HR 0.85; 95% CI: 0.74, 0.97) and greater FEV1/FVC (adjusted mean difference 0.01; 95% CI: 0.003, 0.03). Late menarche (age >15) and early menopause (age <47) were also associated with greater risk of COPD-related hospitalisation/death (but not lung function), while endometriosis was associated with greater FEV 1/FVC (not COPD-related hospitalisation/death). Early menarche (age <12 years) was associated with lower FEV 1/FVC (but not COPD hospitalisation/death). Associations with PCOS or ovarian cysts; any HRT use; hysterectomy-alone; and both hysterectomy and bilateral oophorectomy were in opposing directions for COPD-related hospitalisation/death (greater risk) and FEV 1/FVC (positive association).
Conclusions: Multiple female reproductive health indicators across the life course are associated with COPD-related hospitalisation/death and lung function. Further studies are necessary tounderstand the opposing associations of PCOS/ovarian cysts, HRT and hysterectomy with COPD and objective measures of airway obstruction.