Respiratory Allergies: What Is Changing?

Respiratory allergies are not simply becoming more common: they are changing. They now affect more people, last longer and often cause more severe symptoms than in the past.

Dr Davide Indellicati, Director of the Respiratory Medicine Department at ASL CN2, explains this trend: “Respiratory allergies are indeed becoming more common and today represent one of the most widespread chronic conditions, particularly in our part of the world and in more industrialised areas. When we talk about respiratory allergies, we are essentially referring to allergic rhinitis and allergic asthma. These are two very different conditions, but they are linked by a common thread. When the symptoms of these conditions are severe, they can significantly affect quality of life, including sleep quality and concentration at school or work. That is why they need to be properly treated and managed.”

Allergies on the Rise

There is no single explanation for the increase in respiratory allergies. Genetic predisposition continues to play an important role. However, genetics alone cannot explain why cases have risen so sharply in recent years or why symptoms have become more complex.

The answer appears to lie largely in the environment around us. “We hear a great deal about climate change and global warming. From the perspective of allergies, this means considering factors such as rising temperatures and milder seasons. As a result, plants produce larger quantities of pollen, begin flowering earlier and the pollen season lasts much longer,” explains Dr Indellicati.

Extreme weather events, including sudden thunderstorms, rapid changes in temperature and strong winds, also play a role. “These conditions can cause pollen grains to fragment into much smaller particles, allowing them to penetrate deeper into the airways. Cases of asthma attacks following thunderstorms have been well documented. This phenomenon is known as thunderstorm asthma,” he adds.

Air pollution is another important factor that increases the impact of allergens. “Some people mistakenly believe that living in a city means less exposure because there are fewer plants. In reality, the opposite is true,” continues Dr Indellicati. “We observe more severe and longer-lasting allergic symptoms in urban areas because of fine particulate pollution. On the one hand, pollution causes inflammation of the airways; on the other, it makes pollen more aggressive and allergenic.”

Allergies, the Common Cold, Sinusitis or Asthma?

Not every sneeze has the same cause, and distinguishing a respiratory allergy from the common cold or sinusitis is the first step towards appropriate treatment.

“Allergic rhinitis is characterised by repeated bouts of sneezing, a runny nose with clear, watery mucus and a sudden onset when a person comes into contact with the allergen to which they have become sensitised,” explains Dr Indellicati. “It also responds quickly to antihistamines. The hallmark symptom is itching. In addition to a runny nose, allergic rhinitis is associated with itching of the eyes, nose and palate.”

A runny nose caused by the common cold, on the other hand, results from a viral infection. Unlike allergies, a cold is usually accompanied by general malaise, a sore throat, fatigue and does not improve with allergy medication.

Sinusitis is different again. “It is an infection of the paranasal sinuses. The bones of our skull contain cavities that can become blocked with mucus. This mucus may become infected and inflamed, leading to sinusitis, which is characterised by severe nasal congestion, headache, pain over the affected sinus areas—typically the forehead and cheekbones—and may also involve loss of smell, sometimes loss of taste, fever and general malaise,” explains Dr Indellicati.

Asthma, by contrast, affects the lower airways, including the trachea and bronchi. According to Dr Indellicati, its symptoms include “shortness of breath, wheezing, coughing and a feeling of tightness in the chest. All of these symptoms can be triggered by allergies, but it is important to remember that not all asthma is allergic. There is also non-allergic asthma.”

You Can Develop Allergies as an Adult

More and more people are discovering they have allergies later in life, even after years without experiencing any symptoms.

“There is a long-standing misconception that allergic diseases are confined to childhood. In reality, that is not the case,” says Dr Indellicati. “An allergy is an abnormal response of the immune system to a substance that comes into contact with our body and that is harmless for the vast majority of people. However, in some individuals it is recognised as a threat. This can happen at any age because the immune system changes throughout life.”

This process can occur at any stage. “A person may have tolerated an allergen for years without any symptoms and then suddenly reach a threshold where the immune system recognises it as harmful and begins reacting in the same way every time,” he explains.

Although this discussion focuses on respiratory allergies, the same principle is even more relevant in the case of drug allergies. “For example, someone may have taken the same antibiotic several times during their life without any problems, only to develop an allergic reaction later because they have become sensitised to that substance.”

Towards More Personalised Treatments

In recent years, the treatment of respiratory allergies has advanced considerably. Today, the aim is not only to relieve symptoms but, whenever possible, to address the underlying cause of the condition and reduce its progression over time.

Dr Indellicati first distinguishes between symptomatic treatments and therapies that target the cause of the allergy.

“New-generation antihistamines are much more effective at controlling symptoms and have significantly fewer side effects. Many people still associate antihistamines with drowsiness, but this side effect has been greatly reduced in newer formulations.”

There are also corticosteroid nasal sprays. “The products currently available are very safe, with extremely low absorption into the body. They can therefore be used safely. They are more effective than antihistamines at relieving symptoms and provide longer-lasting relief,” reassures Dr Indellicati.

When it comes to treating the underlying cause of the allergy, allergen immunotherapy—commonly known as allergy vaccines—is the only treatment shown in clinical studies to modify the natural course of the disease. “It changes the allergy profile itself. Immunotherapy can be administered either sublingually or by injection. The duration of treatment depends on the patient’s clinical history and the specific allergen involved, so it cannot be generalised. Every allergen and every vaccine is different.”

For patients with allergic asthma who do not respond adequately to conventional treatments, biologic therapies are now available. “These treatments are effective provided the patient has been correctly classified according to the appropriate phenotype. Both immunotherapy and biologic treatments work when the patient has been carefully selected and the treatment is targeted at the underlying cause of the allergy.”

Prevention and Common Myths

When it comes to respiratory allergies, medication is important, but it is not the only available strategy. Daily habits can also make a significant difference, provided people first know exactly what they are allergic to.

“Every region has pollen calendars. We know that certain allergens, such as grasses, peak in May and June,” says Dr Indellicati. “Here in Piedmont, hazel pollen is particularly common, with peak flowering between February and March. Once we know which allergen is responsible, we know when we are most likely to experience symptoms and can adopt behaviours that help reduce exposure.”

He recommends avoiding outdoor running on windy days, when pollen levels are at their highest, and keeping car windows closed when driving near fields where allergenic plants are present.

If the allergen is perennial, such as house dust mites, management becomes more challenging because they are present all year round in homes and indoor environments. “It is advisable to reduce surfaces where dust mites accumulate, such as carpets, curtains and heavy blankets. Dust mites also thrive in warm, humid conditions, so keeping rooms well ventilated and airing them regularly can help.”

For people allergic to pets, it is not always necessary to part with their dog or cat. However, limiting exposure overnight can be beneficial by preventing pets from sleeping in the bedroom. “It is not an easy decision, but at night you are no longer enjoying the companionship of the animal while continuing to breathe in the allergens it releases into the room for seven or eight hours. This is especially true for cats, whose dander becomes airborne and is considered a particularly potent allergen.”