Gender differences in COPD: are women more susceptible to smoking effects than men?

Abstract

BackgroundThe number of female smokers developing chronic obstructive pulmonary disease (COPD) is rapidly increasing, but whether or not there exists a differential susceptibility by gender remains controversial. Methods How smoking behaviour and subsequent lung function reduction differed by gender was examined in a study including 954 subjects with COPD and 955 subjects without COPD. The study focused on two subgroups: subjects with COPD <60 years of age (earlyonset group, n¼316) and subjects with COPD with <20 pack-years of smoking (low exposure group, n¼241). Results In the low exposure group, female subjects with COPD had lower forced expiratory volume in 1 s (FEV 1 ) % predicted (48.7% vs 55.8%, p¼0.001) and more severe disease (50.4% vs 35.6%, p¼0.020, in GOLD (Global Initiative for Chronic Obstructive Lung Disease) stage 3 and 4) than male subjects with COPD. Females also had lower FEV 1 % predicted (50.6% vs 56.0%, p¼0.006) and more severe COPD (41.7% vs 31.1% in GOLD stage 3 and 4, p¼0.050) in the early-onset group. Using multivariate regression, female gender was associated with 5.7% lower FEV 1 % predicted in the low exposure group (p¼0.012) and a similar trend was observed in the early-onset group (p¼0.057). The number of pack-years was not significantly associated with lung function in female subjects with COPD in this study, and the doseeresponse relationship between smoking and lung function differed by gender at lower levels of smoking exposure. Interaction analysis suggested that the effect of smoking on lung function might be different by gender (p¼0.027 in all subjects with COPD). Conclusions Female gender was associated with lung function reduction and more severe disease in subjects with COPD with early onset of disease or low smoking exposure. The findings may suggest a gender difference in susceptibility to the lung-damaging effects of cigarette smoking, but alternative explanations should be considered.For many years chronic obstructive pulmonary disease (COPD) was considered a disease of men, with higher global prevalence in men than in women. Today the number of women with COPD is rapidly increasing, and for the first time the number of deaths from COPD in women have surpassed those in men in the USA. 1 This development has been attributed to changes in the historical differences in smoking behaviour in men and women. Recent research has suggested that women may be more susceptible to the lungdamaging effects of smoking, but the findings are inconsistent. Several studies have indicated an increased female susceptibility to smoking-related decline in lung function, 2e7 whereas other studies have suggested an opposite gender effect.8 Whether or not there exists a differential susceptibility by gender remains controversial, and little is known about the mechanisms and implications of a possible gender difference in COPD.Maleefemale differences are often divided into sex-related (biological) and gender-related (environmental and socio-cultural) differences. 9 In this manuscript, w...

Factors influencing pharmacological treatment in COPD: a comparison of 2005 and 2014

“…Women are known to be more susceptible to developing COPD [29] and have less declining COPD-related mortality rates than men [30], but factors influencing sex differences in treatment are still an understudied area. Women have been reported to have more symptoms and more exacerbations in COPD [31], but as our analyses adjusted for both CAT and CCQ scores and for previous frequent exacerbations, difference in these factors should not explain the increased medication in women in 2014.…”

Burden of chronic obstructive pulmonary disease: Healthcare costs and beyond

“…10 The diagnosis of COPD in females increased in the United Kingdom as well as Canada, whereas rates of diagnosis have plateaued in males. 14,15 Recent studies have shown more severe disease than previously noted in both smokers and nonsmokers with a substantial prevalence (3%-11%) in life-long nonsmokers, most likely related to nontobacco environmental exposures or infectious etiologies. 16 As noted, COPD is under diagnosed and may be related to patients failing to recognize early symptoms and restrict activities to avoid symptoms.…”

Smoking cessation treatment for COPD smokers: the role of counselling

“…About 85-90% of cases of this disorder are due to tobacco consumption. Around 15-20% of smokers can develop COPD during their lifetime [1,2].…”