Asthmatics harbor a special type of inflammation in the airways that makes them more responsive to a wide range of triggers, leading to excessive narrowing with consequent reduced airflow and symptomatic wheezing and dyspnea.
CAUSES ,RISK FACTORS AND TRIGGERS
- DIET-diets low in antioxidants such as vitamin C and vitamin A, magnesium, selenium, and omega-3 polyunsaturated fats (fish oil), Vitamin D deficiency
- DIET -high in sodium and omega-6 polyunsaturates
- AIR POLLUTION– sulfur dioxide, ozone, and diesel particulate and nitrogen dioxide ,Car Exhaust,
- ALLERGENS– House Dust Mites, centrally heated poorly ventilated homes with fitted carpets, Domestic pets, particularly Cats Fur, Dog Fur, Pigeon Droppings, Cockroaches, Rabbit, Grass Pollen, Ragweed, Tree Pollen, and Fungal Spores, Dust Mite, mould growth following water damage to a home.
- ODOURS-Body deodorant, Perfumes, Nail Polish,Talcum Powder,Beaching Powder, Paint sprayers, chemical fumes, gases , Hairdressing ,Hair Colouring ,Toilet Cleaners commonly develop asthma owing to exposure to aerosols
- DRUGS-paracetamol, aspirin, beta blockers anti hypertensive drug,anti-biotic
- FOOD -Food-Coloring Agent, Shellfish Crab Prawn,Nuts Almond, Brinjal,Tomato,Grapes,Pineapple,Milk products,Egg, Cold food,Ice cream, Sulfites and preservatives added to some types of foods and beverages, dried fruit, processed potatoes Finger chips, beer and wine
- LACK OF BREAST- FEEDING
- PREMATURITY AND LOW BIRTHWEIGHT BABY
- Lower maternal age
- Cigarette smoke exposure
- Cigarette smoking
- Tobacco chewing
- Betel nuts
- Oral Contraceptive Pill
- Exercise -sports such as cross-country running in cold weather, overland skiing, and ice hockey than in swimming.
- Laughter may also be a trigger.
- Cold and Hot weather and when the weather changes.
- Hyperthyroidism and hypothyroidism
- Gastroesophageal reflux
- Genetic Predisposition– genes on chromosome 5q, including the T helper 2 (Th2) cells interleukin (IL)-4, IL-5, IL-9, and IL-13, which are associated with atopy.
- Infections –Rhinovirus,Mycoplasma and Chlamydophila,respiratory syncytial virus infection in infancy
- Hygiene hypothesis– proposes that lack of infections in early childhood (lower levels of infection may be a factor in affluent societies )preserves the Th2 cell bias at birth, whereas exposure to infections and endotoxin results in a shift toward a predominant protective Th1 immune response.
- Atopy-Patients with asthma commonly suffer from other atopic diseases, particularly allergic rhinitis, , and atopic dermatitis (eczema).
- Use of INSECTICIDE,PESTICIDE,RODENTICIDE,WEEDICIDE in agricultureOrganophosphorus Poison(Op Poison)-Malathoin, Tetron, Parathion,Chlorthoin,Diazion(Tik 20)Organo Chlorines-Ddt,Aldrin,Endrin,Endosulfan,Benzene Hexa Chloride
Airway inflammation in asthma is associated with airway hyperresponsiveness (AHR), the physiologic abnormality of asthma, with variable airflow obstruction.
|Inflammatory cells –
Smooth muscle cells
AHR Structural changes
Effects of Inflammation
Epithelial damage may contribute to AHR in a number of ways,
a.including loss of its barrier function to allow penetration of allergens
b.loss of enzymes (such as neutral endopeptidase/ neprilysin) that degrade certain peptide inflammatory mediators like bradykinin
c.loss of a relaxant factor (so-called epithelial-derived relaxant factor)
d.exposure of sensory nerves, which may lead to reflex neural effects on the airway.
2.AIRWAY SMOOTH MUSCLE-Hypertrophy and hyperplasia of airway smooth muscle.
3.VASCULAR RESPONSES -There is increased airway mucosal blood flow in asthma, which may contribute to airway narrowing.
4.MUCUS HYPERSECRETION -Increased mucus secretion contributes to the viscid mucous plugs that occlude asthmatic airways. There is hyperplasia of submucosal glands that are confined to large airways and of increased numbers of epithelial goblet cells.
5.NEURAL REGULATION- Cholinergic pathways, through the release of acetylcholine acting on muscarinic receptors, cause bronchoconstriction and may be activated reflexly in asthma. Inflammatory mediators may activate sensory nerves, resulting in reflex cholinergic bronchoconstriction. Inflammatory products may also sensitize sensory nerve endings in the airway epithelium such that the nerves become hyperalgesic.
- Chest tightness
- Fear of impending doom
- Wheeze disturb sleep and have led to the use of the term ‘nocturnal asthma’.
- Cough may be the dominant symptom and the lack of wheeze or breathlessness may lead to ‘cough variant asthma’
- Feeble respiratory effort
- Inability to complete sentences in 1 breath
- Quit smoking
- Avoid alchol,beet nut
- Take plenty of deit rich in vitamin A,C,D
- Reduce salt intake
- Avoid playing with pet animals like cat ,dog
- Avoid Body deodorant, Perfumes, Nail Polish,Talcum Powder
- Avoid Sulfites and preservatives added to some types of foods
- Clean your room with wet mop
- Clean your air conditioner filter regularly
- Maintain ideal body weight
- Reduce our air air pollution
- Breast feed your children minimum 6 months.Avoid formulated artificial feed.
- Avoid chemical pesticides, chemical fertilizer for farming
- Avoid herbicides
- Avoid weedicides
- Avoid rodenticide
Lung Function Tests
Blood –CBC, Total serum IgE and specific IgE to inhaled allergens (radioallergosorbent test [RAST]).
Skin Tests -Skin prick tests to common inhalant allergens (house dust mite, cat fur, grass pollen) are positive in allergic asthma and negative in intrinsic asthma, but are not helpful in diagnosis.