Asthma

Asthma is a chronic inflammatory disease of the airways in which the passages that carry air in and out of the lungs become swollen, narrowed, and clogged with mucus. This makes breathing difficult and triggers recurring episodes of wheezing, shortness of breath, chest tightness, and coughing. Asthma affects people of all ages and is one of the most common non-communicable diseases worldwide. While there is currently no cure, asthma can be effectively controlled with the right treatment and a clear action plan, allowing people with asthma to live full, active lives.

Asthma symptoms vary in frequency and severity. They often worsen at night or early morning, and are triggered by specific exposures. Common symptoms include: • Wheezing: a whistling or squeaky sound when breathing • Shortness of breath, especially with activity or at night • Chest tightness or pressure • Persistent cough: often worse at night or triggered by exercise, cold air, or allergens Signs of a severe asthma attack (emergency — seek care immediately): • Rapid worsening of shortness of breath despite using a reliever inhaler • Inability to complete a sentence due to breathlessness • Bluish discolouration of the lips or fingernails (cyanosis) • Rapid breathing with visible use of neck and rib muscles • Confusion or drowsiness • Silent chest (no wheezing on listening: airways so blocked that no air moves)

Asthma results from a combination of genetic predisposition and environmental exposures that cause chronic inflammation of the airways. The exact cause varies by person. Inflammation makes airways hypersensitive — they react to triggers by swelling, producing excess mucus, and going into bronchospasm (muscle contraction around the airways). Common triggers include: Indoor triggers: • House dust mites (in mattresses, pillows, carpets) • Pet dander (cats, dogs) • Cockroach droppings • Indoor mould and dampness • Cigarette smoke and cooking fumes Outdoor triggers: • Air pollution (vehicle exhaust, burning of biomass) • Pollen from grasses and trees • Cold air Other triggers: • Respiratory infections (colds, flu) • Exercise (exercise-induced asthma) • Strong emotions, stress • Aspirin or NSAIDs (in aspirin-sensitive individuals) • Workplace chemicals (occupational asthma)

• Family history of asthma or allergic conditions (eczema, hay fever) • Personal history of other allergic conditions (atopic dermatitis, allergic rhinitis) • Obesity • Smoking or exposure to second-hand smoke, especially in early childhood • Exposure to air pollution, traffic fumes, or indoor cooking smoke • Premature birth or low birth weight • Respiratory infections in early childhood (especially viral bronchiolitis) • Occupational exposures (painters, bakers, farmers, healthcare workers) • Low socioeconomic status and living in crowded or damp housing • African ethnicity: asthma tends to be more severe in Black populations

When asthma is poorly controlled over the long term, complications include: • Severe asthma attacks (status asthmaticus) requiring hospital admission, intensive care, or ventilation • Permanent narrowing of the airways (airway remodelling): fixed obstruction that does not fully reverse • Sleep disruption and daytime fatigue from nocturnal symptoms • Missed school or work days, reduced quality of life • Anxiety and depression related to chronic symptoms and activity limitation • Death: asthma deaths are largely preventable with proper management; most occur due to inadequate treatment or failure to recognise a severe attack

Asthma cannot always be prevented, but symptoms and attacks can be significantly reduced: Identify and avoid triggers: • Use dust-mite-proof mattress and pillow covers; wash bedding in hot water weekly • Keep pets out of the bedroom • Avoid smoke: cigarette smoke is particularly harmful • Keep the home well-ventilated and free of mould and damp • Monitor air quality forecasts and reduce outdoor activity on high-pollution days Medication adherence: • Take prescribed preventer (controller) inhaler regularly, every day: even when feeling well. Preventer inhalers reduce inflammation and prevent attacks; they are not the same as reliever inhalers. • Always carry a reliever (bronchodilator) inhaler for acute symptoms Have an asthma action plan: • Work with your doctor to create a written plan that outlines what to do when symptoms worsen • Monitor symptoms or peak flow readings regularly