Conditions like psoriasis could flare and worsen during wildfire season, according to a recent study published by the Journal of the American Medical Association.
The study focused on the rate of dermatologist visits for psoriasis flares during and after wildfires in surrounding areas, noting an increase in flares in the weeks after a wildfire started. Eczema visits, on the other hand, increased during wildfires, accompanied by an increase in oral and injectable medications to treat it.
Author of the study, dermatologist and professor of dermatology at the University of California, Maria Wei, MD explains that the results show wildfires can have an impact on our skin. “We found that the air pollution from California wildfires were associated with an increase in patient visits to dermatologists for both eczema and psoriasis,” Dr. Wei says.
Near and Far: Wildfire Pollution Spreads
The results also indicate that you don’t have to be directly near a wildfire to experience the effects of one.
“One of the interesting things that we discovered is that wildfire air pollution can affect communities quite a distance from where the fires originate,” Dr. Wei explains. “The two fires we studied were 50 miles and 175 miles away from San Francisco, where the studies’ patient population was located.”
What Is Psoriasis?
Psoriasis is a chronic skin condition that causes rashes with itchy, scaly patches that form on the skin.
New York dermatologist Dennis Gross, MD explains that an overactive immune system causes psoriasis flares. “Normal, healthy skin cells grow and shed on their own,” Dr. Gross says. “However, with psoriasis, the T-cells from the immune system attack healthy skin cells. This causes the skin cells to grow back even faster and pile up on the skin’s surface instead of shedding. Once the cells start to build up, it causes this itchy, painful rash to form. “
There isn’t a cure for psoriasis, but it can be managed.
“Unfortunately, psoriasis is a life-long, chronic condition that can go through periods of remission and flare ups, but there are several treatment options that can help manage the symptoms and prevent them from reoccurring,” Dr. Gross explains.
What Typically Causes Flares?
It’s important to understand what can cause a psoriasis flare when you’re considering treatment.
Dr. Gross explains that flares can be caused by a variety of different things, including genetics and illness. “Psoriasis tends to run in families, so if your parents have it, you are much more likely to have the condition as well,” Dr. Gross says. “Certain infections are also known to cause flare ups because they impact the immune system.”
Smoking has also been linked to worsening psoriasis, by inducing oxidative stress and producing free radicals. Additionally, even minor skin injury can cause a flare.
“Any type of trauma to the skin can trigger the immune system to develop an overactive response and cause a flare up,” Dr. Gross says. “Injuries to the skin can even be as small as minor cuts, scrapes, sunburns, scratches or bug bites.”
Notably, the weather is known to have an impact on psoriasis symptoms as well.
“Psoriasis flare ups are more common during the fall and winter months when the humidity and temperature drops, as that climate exacerbates dry skin conditions,” Dr. Gross explains.
According to New York dermatologist Orit Markowitz, MD, one of the main triggers for psoriatic flares is stress. “Certainly, stress or anything harmful to the body will always flare up any skin diseases, psoriasis being one of them,” Dr. Markowtiz says. “You want to manage your stress, your diet, and apparently you want to manage your atmosphere, though I’m not so sure people are able to do that.”
How Could Air Pollution Cause Flares?
This comes a year after a 2022 study was published examining the relationship between air pollution and psoriasis flares. Over the course of seven years, researchers found that air pollution was worse in the two months before a flare, compared to the two months before the control. They concluded that short term air pollution exposure was associated with an increased likelihood of a psoriasis flare.
It is not known to what extent air pollution might affect the skin condition, but these studies indicate that the quality of our air could have significant impact on the health of our skin.
Wildfires release large amounts of carbon dioxide, carbon monoxide, and fine particulate and vegetation into the atmosphere. Those fine particles are so small that they can penetrate deep into the lungs, causing asthma attacks, reduced lung function, heart failure, and premature death. Skin that is suffering from conditions like psoriasis and eczema have disrupted skin barriers, which allows particles like air pollution to physically settle into deeper layers of the skin. Air pollutants also induce oxidative stress on skin cells, which can cause psoriatic flares just like smoking cigarettes can.
Our understanding of how this and other kinds of air pollution might affect skin conditions like psoriasis is rapidly expanding. It’s only in the past year that research has demonstrated a link between high quantities of air pollution and an increased risk of psoriasis flares.
But now that we know it could make psoriasis worse, what can be done about it?
Eagan, MN dermatologist Charles Crutchfield III, MD explains that treatment for psoriasis has come a long way. “Luckily, we’ve entered a new generation of treatments,” says Dr. Crutchfield. “By combining topical and systemic medications—including oral and injectables—and biologic agents, we’re able to achieve 95- to 100- percent clearing with most patients.”
There are over the counter options like lotions that include coal tar and salicylic acid, but a vast majority of psoriasis treatments will need to be prescribed or administered by a professional.
Dr. Markowitz explains that often, several treatments must be combined to see results. “Psoriasis is its own kind of disease entity,” Dr. Markowitz says. “We just kind of assume that if you put steroids on inflammation, that it will go down. But with psoriasis, when the scales and plaque are thick, sometimes you need to thin things out a bit so that topical solutions can get in there and work.”
Phototherapy is a common treatment to help slow down psoriasis.
“This is a type of light therapy that involves exposing your skin to ultraviolet (UV) light to help slow the growth of skin cells and reduce scaling,” Dr. Gross explains. “The key to this treatment is to be very cautious about your sun exposure and keep the unaffected skin protected with an SPF of 30 or higher.”
Sunlight can also help improve psoriasis, but it’s important to remain protected and cautious.
“Just remember, too much sun can have the opposite effect and cause sunburns, which will worsen your psoriasis symptoms,” Dr. Gross says.
Prescription drugs are often introduced when flares impact the joints in order to avoid damage caused by the inflammation.
“There are systemic therapies we use especially if the psoriasis is impacting the joints,” Dr. Markowitz says. Inflammation of the joints is painful and may also lead to permanent damage. “Patients aren’t just uncomfortable, but some of those changes are irreversible.”
Preventing a Weather– or Pollution-Related Flare
Neither the weather nor the presence of air pollution is within your control, but there are steps you can take to reduce your risk of developing a flare.
Dr. Wei noted in her published study that staying indoors may help. “We hypothesize that staying indoors during days with high levels of air pollutants and having an indoor air purifier can help,” she says.
You certainly can’t stay inside all the time, so it’s also important to do what you can to keep your skin barrier strong.
“The best way to prevent an environmental psoriasis flare up is to keep your skin moisturized and protected throughout the day,” Dr. Gross says. “I recommend looking for moisturizers or lotions that are fragrance-free, formulated for sensitive skin, and feature ingredients like hyaluronic acid or niacinamide which help to soothe and strengthen the moisture barrier, and reduce inflammation and redness.”
Despite improving with vitamin D and sunlight, it’s still extremely important to practice sun protection to keep your skin healthy and calm. Even a small sunburn can prompt a flare.
“For sun protection, I recommend incorporating a physical sunscreen into your daily routine, like the All-Physical Lightweight Wrinkle Defense SPF 30 ($42) that has broad spectrum protection from both UVA and UVB rays,” Dr. Gross explains. “This will act as a protective shield reflecting the harmful rays and free radicals away from your skin and preventing damage before it occurs.”