Climate change and . . .
Impact: More allergies and bug bites
Think your plants are blooming earlier? You're not imagining things. One of the ways the U.S. Environmental Protection Agency (EPA) tracks climate change is by cataloging the spring blooms of honeysuckle and lilacs across the country. The evidence shows that “earlier dates appear prevalent in the last few decades."
Earlier blooms and grass growth have two measurable health effects. The first is more pollen in the air; pollen seasons in the U.S. are, on average, 20 days longer now than in 1990 — and the air is filled with 21 percent more pollen, according to a University of Utah study published in February in the Proceedings of the National Academy of Sciences. In counties where the pollen season was trending earlier (from 2002 to 2013), hay fever rates were 14 percent higher than in counties where spring arrived in the normal range, according to a 2019 University of Maryland study.
A second factor is the rise of dangerous bug bites. Cases of diseases carried by ticks, mosquitoes and fleas tripled in the United States between 2004 and 2016, according to a report from the U.S. Centers for Disease Control and Prevention. The CDC reports that the rate of Lyme disease alone doubled between 1991 and 2014, driven at least in part by climate change; disease-carrying deer ticks are most active in warmer temperatures — and their American habitat range is expanding.
Impact: Heat-related ailments
Yes, Los Angeles is known for its dry heat. But in September 2020, L.A. County recorded its highest temperature on record — 121 degrees — a few weeks after California's Death Valley reached what might be the highest temperature ever recorded on Earth: 130 degrees. In such conditions, going outside for mere minutes is treacherous for anyone, but especially for older people.
"As we age, our physiological responses to hot temperatures — such as sweating, releasing heat through dilated blood vessels at the surface of the skin, and thirst — diminish,” says Soko Setoguchi, M.D., professor of medicine and epidemiology at Rutgers University's Robert Wood Johnson Medical School and its School of Public Health.
Heat-related illnesses and hospitalizations are increasing. Says the EPA, which surveys health data as an indicator of climate change: “Relatively high hospitalization rates in the Southeast and Midwest suggest a connection between hotter and more humid summers and increased rates of heat-related illness, compared with other regions.” Hospital admissions and emergency room visits for kidney failure, urinary tract infections and other health problems have also increased for older adults during heat waves. It appears that our medicines don't help the situation. In a 2020 study of more than 375,000 older adults with chronic health conditions, Setoguchi found that drugs such as loop diuretics, ACE inhibitors/angiotensin II receptor blockers, and antipsychotics boosted the odds of hospitalization for heat-related problems by up to 33 percent.
Risk: Rising ozone levels
Impact: Increased lung disease
It's well known that smoking rates in America have been declining — from nearly 21 percent of adults in 2005 to 14 percent in 2019, according to the CDC. And so it would stand to reason that lung disease would also be declining. That may be true in many instances, but not for emphysema; rates of this breath-stealing ailment have remained generally steady, the American Lung Association says.
One culprit, scientists surmise, is rising levels of ground ozone, an invisible gas associated with automobile exhaust and factory emissions. The link to climate change is this: Heat and sunlight convert pollutants into ozone. (This is different from the Earth's “ozone layer,” which is 9 to 18 miles above the surface. That atmospheric ozone protects us against radiation from the sun, and is a good thing.)
In 2019, Joel Kaufman, a University of Washington physician and epidemiologist, released a study of 7,000 urban-dwelling midlife and older adults that found ozone was significantly associated with the progression of emphysema-like changes on lung scans and a decline in lung function. “I was very surprised,” says Kaufman of the lung scans that he examined. “Fractions of the pixels on the scans showed there was air where normal lung tissue should be. These emphysema-like changes in the lungs were as much in relation to outdoor ozone concentrations at people's homes as they were to smoking cigarettes."
Similarly, 1 in 4 Americans with chronic obstructive pulmonary disease (COPD) today are nonsmokers, a 2017 CDC study found.