A variety of reproductive factors, such as the age at which menstruation begins and the onset of early menopause, have been identified as contributing to an increased risk of Chronic Obstructive Pulmonary Disease (COPD), a collective term for progressive lung conditions such as emphysema and chronic bronchitis that lead to breathing difficulties. This connection was highlighted in research published in the journal Thorax, which also pointed out that miscarriage, stillbirth, infertility, and having more than three children can elevate the risk of developing COPD.
The study sheds light on the significant differences in how COPD affects men and women, noting that women are likely to experience severe COPD at younger ages compared to men. Despite smoking being a significant risk factor, a notable number of non-smoking COPD sufferers are women. This observation underscores the potential influence of female hormones on COPD risk, a topic previously explored but often limited by methodological challenges. To address these challenges and provide more comprehensive insights, the researchers leveraged data from the International Collaboration for a Life Course Approach to Reproductive Health and Chronic Disease Events (InterLACE) consortium, which pools data from over 850,000 women across 12 countries.
The study specifically focused on three groups of women, totalling 283,070 participants with an average age of 54, who had provided detailed information on their reproductive history and COPD status. These groups were drawn from the Australian Longitudinal Study on Women’s Health 1946–51, the UK Biobank, and the Swedish Women’s Lifestyle and Health Study. The analysis considered various factors, including ethnicity, education level, smoking duration, asthma history, and BMI, over an average monitoring period of 11 years, during which 4% of the participants developed COPD at an average age of 63.
Findings indicated that women with COPD were generally older, had less education, were more likely to be obese, and had a history of smoking and asthma. Interestingly, several reproductive factors were linked to COPD risk. Early menstruation (before age 11) and late menarche (after age 16) were associated with an increased risk of COPD, as was having more than three children compared to having two. Infertility and a history of multiple miscarriages or stillbirths also elevated the risk, as did menopause occurring before the age of 40.
While acknowledging the observational nature of the study and its limitations, including a lack of detailed information on hormonal contraception, hormone replacement therapy (HRT), and certain environmental factors, the researchers propose that oestrogen might play a significant role in the risk of COPD in women. They suggest that the effects of oestrogen on lung health may vary depending on the stage of reproductive life, with prolonged exposure to oestrogen potentially harmful in earlier stages but possibly offering protective benefits later on. Factors such as autoimmune diseases, air pollution, being underweight, and socioeconomic factors were also mentioned as potentially influencing the risk of COPD.
This research emphasizes the complex interplay between reproductive health and lung disease, suggesting that managing and preventing a greater understanding of these relationships may benefit COPD in women. The findings not only contribute to the growing body of evidence on gender differences in COPD but also highlight the need for further studies to explore the underlying mechanisms by which reproductive factors influence lung health.
More information: Chen Liang et al, Female reproductive histories and the risk of chronic obstructive pulmonary disease, Thorax. DOI: 10.1136/thorax-2023-220388
Journal information: Thorax Provided by BMJ
