It's been so bitter cold in New England this winter that it didn't surprise Dr. Mark R. Windt when one of his patients came in wheezing and complaining of shortness of breath.
The cold air had aggravated her asthma.
The daytime high temperatures sometimes weren't getting out of single digits.
"That is cold, COLD," said Windt, a specialist in allergies, immunology and pulmonology in North Hampton, N.H.
Scientists have attributed the frigid temperatures and historic snowfalls to storm tracks that have become stronger and more frequent because of increased greenhouse gas emissions that alter atmospheric conditions.
"There's no doubt climate change had an effect on my patient's asthma and is having an effect on the health of others," Windt said.
Windt and a majority of his colleagues in the American Thoracic Society who specialize in the treatment of respiratory illnesses are connecting some of their patients' disorders to climate change.
A recent survey by the society found that the majority of its members believe climate change is having a negative impact on the health of their patients. The survey was published in the February issue of the Annals of the American Thoracic Society.
The survey, which was conducted by the Center for Climate Change Communication at George Mason University, polled 5,500 U.S. ATS members and asked a series of questions about climate change and its effect on patients.
Nearly two-thirds of those responding to the survey reported that they have already observed symptoms among their patients they attribute to climate change.
The doctors, registered nurses and respiratory therapists who answered questions said they were seeing worsening of asthma associated with exposure to ozone or other pollutants, longer and more severe allergy seasons, and more cases of acute and chronic lung conditions.
The survey also showed the doctors are worried that four distinct groups will be disproportionately affected by climate change disorders: people with chronic diseases; the poor; children under 4; and adults over 60.
One of the authors of the study, Gary Ewart, senior director of ATS government relations, said the survey results will not only help medical professionals become better prepared to treat patients with climate-change-related illnesses but will bring additional attention to the need to address climate change.
Nearly 75 percent of survey respondents said they thought physicians should play a role in informing the public about climate change.
Ewart said the results also indicate a need for physicians and scientists to further prod national and international policymakers to address emissions of greenhouse gases.
A discussion on the mitigation of climate change also stirs talk about climate change as a public health issue, he said.
"Climate change must be taken seriously from a public policy standpoint and a public health standpoint," Ewart said. "One of the things this survey does is shows the importance of healthcare groups taking a stand on climate change, and educating their members and patients that climate change is a healthcare issue."
High temperatures can lead to elevated ozone levels that have been associated with the exacerbation of respiratory disease, including respiratory infections in children, and a worsening of asthma in children and adults.
Changing temperatures and rising carbon dioxide levels are lengthening the pollen season and increasing the production and allergic potency of pollen, the ATS points out in an analysis of the survey results. That may explain a recent increase in the frequency of allergic disease, according to the study.
Climate change also promotes the spread of insect-borne infectious diseases such as malaria and dengue fever, according to the study. It contributes to the destruction of housing and public health infrastructure through storms and floods that result in injuries and unsanitary conditions.
Back in New Hampshire, Windt prescribed medication for his patient's asthma and recommended that she wear a mask to lessen the harshness of the cold air entering her lungs.
As a doctor confronting climate change illnesses, Windt doesn't simply treat his patients' physical symptoms; he takes time to explain the connection of their sickness to wide-scale changes in Earth's climate system.
"It's really in the trenches where we need to talk about climate change," Windt said. "It's not some esoteric professorial discussion. People need to know how it affects them."