Women and COPD: Suddenly Epidemic but Largely Underdiagnosed
Date: May 1, 2013
Until a few years ago, chronic obstructive pulmonary disease (COPD) was thought of as a disease mainly of middle-aged men. Literature reports of the progressive lung disease most often caused by cigarette smoking were predominantly done in males, and physicians trained into the 1990s were taught that it was a disease affecting men.
But over the last 10 to 15 years, the number of women presenting with COPD has sharply increased, says pulmonologist and COPD researcher Enid Neptune. Today, about 60 percent of COPD patients seen at Johns Hopkins and other centers are women, and more women than men die from COPD.
Smoking was uncommon among women until the 1930s, when tobacco companies began marketing to women. After the 1963 surgeon general’s report linking smoking to lung cancer, smoking in men began to decrease but stayed constant in women. In the 1970s, manufacturers marketed cigarettes to women as a means of weight control. COPD is one of several consequences, along with lung cancer and cardiovascular problems, that has developed in women from 20 to 30 years of cigarette smoking, Neptune says.
Thanks to history, however, “physicians are much less likely to make the COPD diagnosis in women,” Neptune says. “We want to make sure the pulmonary community understands this is an epidemic.”
Compounding the problem, COPD research has been underfunded, says pulmonologist Robert Wise, co-director of Johns Hopkins’ Center for Translational Research in COPD.
“There has been very little interest from the public in COPD as a women’s disease,” he says, “even though more women die from COPD than from breast cancer.” Because people think of COPD as a disease smokers bring on themselves, “there are no telethons, no disease-awareness ribbons or grocery products that give a portion of sales toward COPD research.” The most severe patients are “invisible” to the public, he says, homebound on oxygen.
With no cure for COPD, Hopkins investigators have taken on a few research projects to better understand and treat the condition. Wise is the principal investigator for two clinical trials, one of which is evaluating whether the antihypertensive drug losartan can stabilize or improve lung function in people with COPD. In a previous study in mice, led by Neptune, the drug helped prevent or reverse inflammation and lung damage.
Another trial is testing the potential of the broccoli sprout extract sulforaphane to stimulate Nrf2, a molecule that turns on numerous antioxidant and pollutant-detoxifying genes to protect the lungs from cigarette smoke. COPD patients have significantly lower levels of Nrf2 than nonsmokers. Additional studies are planned to explore the efficacy and mechanisms of sulforaphane to increase bacterial clearance and restore steroid sensitivity in COPD lung cells.
On the basic science side, Neptune wants to model the effects of cigarette smoking in women in an animal model, to better identify affected pathways and help with more targeted drug development or smoking cessation programs for women.
Studies have shown that women have a harder time quitting smoking, but when they do, they have a greater recovery of lung function than men. And, says Neptune, “There is no point in time in which you don’t get a life expectancy benefit from stopping smoking.”