Sex, gender differences impact asthma experiences and treatment

Sex and gender can influence the pathogenesis, clinical course, diagnosis, treatment and management of asthma, according to a review published in The Journal of Allergy and Clinical Immunology: In Practice.

Usually defined as male or female, sex is based on genetically determined anatomical and physiological attributes, Christine R. Jenkins, MBBS, MD, FRACP, head of the respiratory group at George Institute for Global Health in Sydney, Australia, and colleagues wrote.

Gender, which is more complex, encompasses socially constructed roles, behaviors and expressions of identity in girls, women, boys, men and gender-diverse people, the researchers continued, adding that there is no universally recognized definition of gender. Previous literature about asthma has been inconsistent in addressing sex and gender, the researchers continued, preventing accurate data interpretation and hindering research.

Effects of sex, gender on asthma risks

Asthma is more prevalent among males before puberty and more prevalent among females afterward due to fluctuations in sex hormones during its pathogenesis, the researchers wrote.

Testosterone could protect patients against inflammatory processes, whereas estrogen and progesterone directly modulate the immune pathways that are involved in the pathogenesis of asthma, the researchers explained.

During the menstrual cycle and pregnancy, women with asthma experience worse symptoms. Menopause has been associated with more severe asthma and an increased risk for new-onset asthma as well.

Anatomical differences also play a role. Bronchial airways and lung parenchyma grow proportionally in girls but not in boys, resulting in disproportionately fewer alveoli for the number of airways.

Yet males then develop airways with larger diameters, greater lung volumes, maximum expiratory flow and larger diffusion surfaces than females on maturation, which may drive differences in asthma experiences, the researchers wrote.

Occupational hazards may expose men and women to different asthma triggers based on the gender roles traditionally participating in those jobs, such as wood dust among carpenters and chemicals in hairdressing salons.

Tobacco smoke can trigger asthma symptoms, and more men than women smoke worldwide. But men also are more likely to engage in physical activity, which can improve asthma control and quality of life.

According to some studies, there are no significant differences in asthma severity between men and women, although others report more severe asthma as well as more morbidity and mortality, in addition to hospitalization, among women.

Chronic comorbidities with asthma are more common among women than men, including osteoporosis, obesity, anxiety and depression. Additionally, women with asthma are more likely to have dyslipidemia, type 2 diabetes and hypertension.

When women experience asthma symptoms, they perceive them as more bothersome than men, even if their severity and lung function are similar. The researchers acknowledged that the reasons behind these differences are poorly understood, though “female gender” and poor quality of life predicted increased perception of dyspnea.

Breathing difficulties associated with obesity and anxiety, which are more common among women, may be misattributed to asthma. Plus, men might be uncomfortable with reporting their symptoms due to expectations of their gender roles.

Differences in treatment, management

Health care professionals (HCPs) may play a role in differences too. Women often say that HCPs do not believe them when they report symptoms, preventing them from receiving adequate care. HCPs also may display more clinical inertia and provide fewer preventive interventions with their women patients, especially when the HCPs are men.

Also, women experience greater rates of physician office and ED visits due to their asthma and are less likely to get spirometry and specialist care, possibly due to provider or patient behavior, the researchers wrote.

Women are more likely to engage with their HCP when necessary, regularly use a peak flow meter and have an asthma management plan, the researchers continued, yet report lower quality of life even when they have the same forced expiratory volume test results as men.

Women HCPs may benefit both men and women, especially in shared decision-making, preventive interventions and lifestyle modification, the researchers wrote.

Noting conflicting results in the literature, the researchers called for more information on sex- and gender-based differences in response to interventions, although men appear to receive more aggressive treatment even when women report worse symptoms.

There seem to be differences in asthma management as well. For example, women are more likely to have psychological comorbidities, and patients with comorbid depression are less adherent to asthma treatment than patients without depression.

Also, men are more likely to be prescribed oral corticosteroids for asthma, and the prevalence and types of comorbidities associated with their use differ between men and women.

And although asthma control during pregnancy is critical, women may reduce or stop taking their asthma medication or stop breastfeeding because of perceived possible effects on their child, despite that inhaled corticosteroid use is safe during pregnancy.

The researchers caution that most large, randomized trials do not build sex and/or gender into their study design even though they have unique opportunities to do so. HCPs and patients alike need to be aware of these differences in diagnosis, treatment and management and take appropriate action based on evidence and not on preconceptions or biases, the researchers concluded.