Asthma can range from a hassle to life threatening – it causes the airways to constrict and can make breathing uncomfortable, labored and sometimes impossible.
Experts are still trying to determine why there are so many adult cases of asthma today.
Hormones, sex, puberty
Asthma rates rose sharply between the 1960s and the turn of the 21st century, possibly due to greater awareness and recognition of the disease. The rise slowed in the early 2000s and prevalence has remained stable or slightly decreased since then, which may reflect better treatments for asthma control.
Although the causes of asthma – in childhood or in adulthood – remain unclear, research indicates that a family history of the disease, allergies, environmental factors and childhood respiratory infections put people at risk. higher risk. Doctors have also identified the characteristics of the disease based on the age of the person when the respiratory problems began.
“In children, asthma tends to be milder,” says Sally Wenzel, pulmonologist and Rachel Carson Chair in Environmental Health at the University of Pittsburgh. “In adults, it’s more unpredictable.”
There are other key contrasts.
Before puberty, asthma affects boys more than girls; in adulthood, the gender disparity is reversed and more women than men suffer from asthma.
The majority of asthma cases in children are related to allergies, but a minority of adult onset cases have this link. There are theories about these differences, such as the potential role of hormones in sex change after puberty, but much is still unknown.
Race, climate change risks
Race also plays a role. Black Americans, Puerto Ricans (but not other Hispanic groups), and Native Americans/Alaska Natives have the highest rates of asthma, and Black Americans die of the disease in disproportionate numbers, according to the Office of Minority Health from the Department of Health and Human Resources. Services.
The reasons are as complex as the disease itself. Officials from the Asthma and Allergy Foundation of America say environmental inequalities, such as those involving air pollution and housing, and health care disparities play a bigger role than genetics in the differences .
Some aspects of climate change have also contributed to the increase in plant allergens. The increased frequency and intensity of thunderstorms – another consequence of climate change – has also been linked to the rise of thunderstorm asthma triggered by changes in atmospheric pressure and storms lifting allergens into the air. After a thunderstorm in Melbourne, Australia, in 2016, for example, experts estimated that at least 9,000 more people than usual sought medical attention for asthma over three days.
Manage symptoms, avoid misdiagnosis
What experts know is that getting proper treatment is crucial when respiratory problems start – at any age.
Asthma management strategies include avoiding triggers – whether allergens, cold air, exercise or respiratory viruses – and using medications, which fall into two general categories .
Treatments that reduce the volume of airway hypersensitivity include corticosteroid inhalers (including Alvesco, Pulmicort, and Flovent) and pills (such as Singulair), which all target inflammatory mediators. The second category includes rescue inhalers (such as Proventil, Ventolin, and ProAir) that can interrupt an asthma attack in progress.
Shawn Aaron, a respirologist at the Ottawa Hospital Research Institute, noticed that many patients referred to him were not responding to treatment, leading him to question whether their diagnoses were correct.
“There are so many conditions that can mimic asthma — anything that causes shortness of breath, coughing, and wheezing,” says Aaron.
He designed a study to reassess the status of 613 adults who had been diagnosed with asthma by a physician within the previous five years. He used the gold standard lung function test, called spirometry, and found that one in three subjects failed to meet the diagnostic criteria for asthma. “And 50% of them have never had lung function tests,” he adds.
Spirometry measures how much air you forcefully exhale after taking a deep breath. For the asthma assessment, you take the test twice, the second time after using an inhaler that delivers bronchodilator medicine to open the airways.
“That’s the problem with asthma — you can breathe in, but you can’t breathe out,” says Wenzel, calling it “air entrapment.” If a patient’s exhalation improves after the bronchodilator, “then it’s asthma,” she says. “The characteristic criterion is an obstruction during the expulsion of air.”
GPs often make the diagnosis based on symptoms alone, Aaron says. Spirometry is not complicated. “It’s easy, cheap and takes 15 (to) 30 minutes,” he adds – but it’s not done by many labs and can be more difficult to access than other lab tests such as blood tests.
Subjects in Aaron’s study who were reclassified as not having asthma were later diagnosed with other conditions that affected their breathing, including allergies, reflux, anxiety or lung disorders chronic obstructive. Twelve patients suffered from serious cardiorespiratory disorders which had been misdiagnosed as asthma.
Misdiagnosis is a common problem, which doctors strive to resolve with more objective measures, such as spirometry, and by carefully excluding other contributing factors or conditions.
Aaron’s study also found that some people who received a proper diagnosis, i.e. with spirometry, no longer had asthma. Their condition had recovered.
Remission is less likely to occur in adults than in children, but that doesn’t mean it never happens. Treatment guidelines suggest tapering off asthma medications in people who have had good control for at least three months, as the disease can wax and wane.
Allergies, pneumonia, other triggers
A 2011 study found that many cases of asthma were associated with a recent respiratory infection. Adults with newly diagnosed asthma were about seven times more likely than those without a diagnosis to have had a lower respiratory infection – bronchitis or pneumonia – in the previous year, and about twice as likely to have had an illness upper respiratory tract like a cold or sinus infection.
A more recent study assessed past health events in 200 adults with newly diagnosed asthma. New allergies were identified in 11% of participants, pneumonia in 8% and upper respiratory tract symptoms in 22%.
This explains my situation. Several months after recovering from pneumonia, I still had rather disturbing bouts of shortness of breath. I followed up with a pulmonologist and was diagnosed with asthma.
Researchers believe that respiratory infections may cause persistent damage to the airways or trigger hypersensitive immune and inflammatory processes, although, as with many aspects of asthma, these hypotheses await further evidence and knowledge.