Improving the management of COPD in women

Introduction

• Chronic obstructive pulmonary disease (COPD) represents a substantial and growing health burden in women. COPD receives limited attention as a women’s health issue, despite growing evidence for gender-related differences in disease risk, progression and outcomes.
• In this review, the authors summarise key literature and provide their thoughts on how to improve the management of COPD in women worldwide.

Risk of developing COPD in women

• The prevalence of COPD and related deaths is growing more rapidly in women than in men,^1–7 with indirect evidence indicating that women may be more susceptible to developing COPD or progressing faster in the disease than men.^2,8–15
• The factors affecting susceptibility are unclear and require further research, but may include differences in genetic predisposition, physical differences, hormonal influences or second-hand risk exposure.
• Tobacco smoking is established as the leading cause of COPD in both genders.⁶
• Globally, the proportion of female smokers is predicted to rise to 20% by 2025.¹⁶ However, there is significant geographic variation, with prevalence plateauing or decreasing in some countries.^5,17–19
• A lag time may exist between smoking and COPD onset, therefore despite declining smoking prevalence in some regions, tobacco use by women is likely to be reflected in a high COPD burden for a number of years.²⁰
• Women represent the greatest proportion of lifetime non-smokers with COPD.²¹ In countries where there is a considerable reliance on biomass fuel for cooking and heating, women are often more likely to be exposed to biomass smoke than men due to a higher burden of domestic responsibilities.^21–25 This may result in clinical characteristics and prognosis similar to that of tobacco smokers.^24,26–29
• Women are also increasingly exposed to COPD risk factors in the workplace, particularly in unregulated ‘cottage industries’ (e.g. leather working, tobacco curing and brick making) in low- and middle-income countries.³⁰
• Living in low- or middle-income countries, and/or having low socioeconomic status itself also increases the risk of developing COPD and associated mortality.^31–33 This is particularly important for women, who are more likely to have lower socioeconomic status than men.³⁴
• Other potential risk factors for COPD in women include airway hyperresponsiveness (AHR) which may be more prevalent in women than men and detrimentally impact on decline in lung function and susceptibility to the effects of smoking.^35,36
• Key suggestion from authors: A multifaceted approach (including educational initiatives, practical steps to minimise risk exposure, political policies, and better treatment) is required to reduce risk exposure and mitigate COPD risk in women.

COPD characteristics and presentation in women

• Compared with men, women with COPD are generally younger, smoke less, have a lower socioeconomic status, and a lower body mass index.^37–42
• Biological differences may explain the gender variations in the presentation of COPD: women have smaller lumina and disproportionately thicker airway walls than men.^39,43
• While some studies have shown similarities in COPD symptoms between genders,^44,45 others have shown that women have more frequent and/or more severe exacerbations, a higher prevalence of acute AHR and higher levels of dyspnoea compared with men.^{22,35,36,38,41,43,46–48}
• Key suggestion from authors: Further investigation is required into the impact of gender-related differences on COPD symptoms and presentation. Physicians should be aware of likely differences in order to improve diagnosis and patient outcomes.

Interactions between women with COPD and healthcare providers

• Gender bias exists in physician awareness of COPD, resulting in a higher rate of mis- or delayed-diagnosis of COPD in women compared with men.^2,37,49,50
• Men and women may perceive the COPD care they receive differently, and the genders may differ in the coping strategies they employ.^50,51
• Key suggestion from authors: Prompt use of spirometry and careful history-taking could help to reduce gender bias in COPD diagnosis.

Focusing on the patient: how does COPD affect women?

• Many studies identify a poorer health status and quality-of-life in women with COPD compared with men.^{39,46,47,52–54}
• Women with COPD report higher levels of depression and anxiety (associated with an impaired quality-of-life and reduced treatment adherence^55,56) than men.^{44,52,57–59}
• COPD exacerbations are associated with prolonged respiratory, social, physical, and emotional impairments in patients. Although, rates of exacerbations have been shown to be higher in women versus men, evidence suggests that outcomes following acute exacerbations may be better in women than in men.^51,60
• More pronounced levels of dyspnoea occur at earlier stages of disease in women compared with men, which may be associated with poorer prognostic scores.⁴¹
• Key suggestion from authors: Further work is needed to elucidate the influence of gender on disease indicators in order to facilitate tailored intervention programmes.

Evidence for treating women with COPD

• Smoking cessation is an important aspect of COPD intervention and may result in greater benefits in women than in men (e.g. lung function improvements in the first year of smoking cessation).⁶¹
• Evidence suggests that women are less successful with long-term smoking cessation than men.⁶²
• Despite the apparent differences in COPD presentation and progression between genders, there is a lack of evidence to guide gender-focused treatment. Current guidelines for the pharmacological treatment of COPD are based on clinical trials that have recruited more men than women and have not compared outcomes between genders.^6,63,64
• Comorbidities associated with COPD vary between genders, and women experience a higher burden than men.^22,26,47,65 For instance, women are more susceptible to asthma, osteoporosis, anxiety and depression, although less likely to suffer from cardiovascular disease.^{26,41,44,46,54,65} The prevalence of these comorbidities may impact treatment choices.
• Key suggestions from authors: There is a need for more clinical data on the gender-specific effects of different interventions, response to treatment and comorbidities. Future trials should include more female participants and prespecified gender-specific sub-analyses.

Summary and future focus

• Better awareness of COPD in women within the healthcare community is important, in order to improve prevention, diagnosis and treatment strategies, with consideration of the biological and cultural differences between COPD in men and women.
• A multifaceted approach (encapsulating policy-makers, the research community, healthcare providers, employers, women, and caregivers) that examines risk avoidance strategies is required, and educational programmes should be put into place for women with COPD, in order to empower patients to manage their disease more effectively.