Panel explores gender differences in prevalence, presentation of obstructive lung diseases

Recent data suggest that gender differences exist in epidemiological and phenotypic manifestations of obstructive lung diseases—differences that can potentially delay diagnosis and impact treatment responses. In a Monday, October 19 session, a panel of experts reviewed the latest science regarding gender differences in three of the most common of these conditions encountered in clinical practice.

The session, Obstructive Lung Diseases in Women—Is There a Difference?, will soon be available for on-demand viewing on the virtual CHEST 2020 meeting platform through January 18, 2021, for registered attendees. Navitha Ramesh, MD, MBBS, FCCP, pulmonary and critical care physician at UPMC Pinnacle health system, served as chair and moderator for the session.

Mariam Louis, MD, FCCP, associate professor of medicine, division of pulmonary, critical care, and sleep medicine at the University of Florida College of Medicine – Jacksonville, opened the presentations with a discussion of COPD in women.

Regarding the prevalence of COPD, Dr. Louis cited a recent study suggesting a global prevalence of 6% for women compared to 9% for men. The prevalence of COPD in women was found to be slightly higher—7% in North America, she said, noting that the prevalence appears to increase with age.

“For example, in women over the age of 70, the prevalence of COPD is close to 16%. That number is quite alarming because in the US, COPD remains the leading cause of death among female smokers, and the third leading cause of death amongst all women,” Dr. Louis said. “With that said, COPD remains underdiagnosed in women. It’s estimated that female smokers are one-third less likely to be diagnosed with COPD compared to their male counterparts, which raises the concern that we may be underestimating the exact burden of COPD in women worldwide.”

Looking at COPD risk factors, Dr. Louis said that, like men, smoking remains the highest risk factor for COPD in women worldwide; however, she noted that a large percentage of women who have COPD are nonsmokers, approximately 25% to 45%.

“The main risk factor for that is exposure to biomass smoke. Worldwide, 50% of households and 90% of rural households use biomass fuels and women, who traditionally do more cooking and are the gatekeepers of the home, tend to be much more exposed to biomass fuels,” she said. “This is an important point, because as we take a history from our patients, we want to really try to get as detailed a history as possible so that we can try to mitigate or minimize the risk factors these women are potentially exposed to.”

Next, Vandana Seeram, MBBS, FCCP, associate professor and medical director of the Pulmonary Function Lab at the University of Florida College of Medicine – Jacksonville, reviewed some of the gender differences between men and women with asthma.

In younger children, she said, there appears to be a slightly higher prevalence of asthma in male children; however, as children reach puberty, females begin to show an increased prevalence, suggesting that the development of increased female sex hormones increases risk factors for asthma.

“So, among children, boys will be worse upfront because of the allergic component compared to girls. And then by adulthood, the prevalence is greatly in favor of women compared to men,” Dr. Seeram said. “There are multiple factors that affect sex disparity and asthma, not just in childhood, but throughout life—genetics, epigenetics, immune responses, and obesity, which is probably the most important environmental factor.”

In the final presentation, Nauman Chaudary, MBBS, FCCP, professor of medicine and director of the Adult CF Center, Virginia Commonwealth University, discussed gender differences in non-CF bronchiectasis.

“As we all know, women possibly tend to do worse when they have bronchiectasis. They show earlier colonization of pseudomonas, increased conversion of mucoid state or more resistant state, and then also increased inflammation as well as increased morbidity associated with bronchiectasis,” Dr. Chaudary said.

Age appears to be associated with prevalence, he said, noting that by the age of approximately 75 years, men have a slightly higher prevalence but women tend to have a higher disease severity.

“There are several possibilities that are thought to underlie these important differences,” Dr. Chaudary said. “Non-CF bronchiectasis is a complex multifactorial pulmonary disease, and it can get affected by the disease microbiology by certain pathogens, as well as the host immunologic response and underlying inflammation that follows that can be influenced by the sex steroid hormones and gender.”