Table 1. Prevalence of asthma in adults and children in studies from India

Region	No.	Age and setting	Method	Prevalence	Salient Features
Mumbai (Chowgule et al, 1998) 3	2,313	20-44 yrs Population based	ECRHS	3.5% by physician diagnosis	9-12% symptom prevalence without diagnosis of asthma
Chandigarh (Jindal et al, 2000) 4	2,116	>18 yrs Population based	IUATLD based questionnaire	3.9% (M) 1.3% (F) Equal in urban and rural	Questionnaire standardized against physician diagnosis
Chandigarh (Gupta et al, 2001) 5	9,090	9-20 yrs School based	IUATLD based questionnaire	2.6% (M) 1.9% (F)	Questionnaire standardized against physician diagnosis
Delhi (Chhabra et al, 1999) 6	18,955	5-17 yrs School based	Questionnaire on wheeze	3.4% (Past wheeze) 11.9% (Current wheeze) 12.8% (M) 10.7% (F)	2.1% (Exercise Induced Asthma) 2.4% (Cold Associated Asthma)
Ludhiana (Singh et al, 2002) 7	2,275	1-15 yrs Population based	Questionnaire on symptoms of asthma	2.6% (Rural)	Modified ATS criteria used for diagnosis
Lucknow (Awasthi et al, 2004) 8	6,000	6-7 and 13-14 yrs School based	ISAAC Questionnaire	6.2% and 7.8% (Wheeze) 2.3% and 3.3% (Asthma)	Part of multicentric (ISAAC III) trial
Multicentric (ISAAC Steering Committee, 1998) 9,10	37,171	6-7 and 13-14 yrs School Based	ISAAC Questionnaire	6.0% (Wheeze) 4.5% (Ever asthma)	Wide variations in different regions worldwide (including within India)
Multicentric (ICMR) (Jindal et al, Unpublished data) 11	73,605	>15 yrs Population based	IUATLD based Questionnaire	2.4% (1.7-3.5% range)	Questionnaire standardized against physician diagnosis

ATS American Thoracic Society, ECRHS European Community Respiratory Health Survey, ICMR Indian Council of Medical Research, ISAAC International Study of Asthma and Allergies in Childhood, IUATLD International Union Against Tuberculosis and Lung Diseases

Table 2. Role of tobacco smoke in asthma 19

Active Smoking	Passive Smoking (environmental tobacco smoke exposure)
Increased bronchial responsiveness	Aggravation and occurrence of increased prevalence of respiratory symptoms
Frequent bronchial irritation symptoms	Bronchial hyper-responsiveness in adults
Increased sensitization to occupational agents	Aggravation of asthma symptoms
Aggravation of acute episodes	Precipitation of acute episodes
Association with asthma severity	Risk factor for development of asthma (both children and adults)
Risk factor for asthma?
Exaggerated decline in lung functions
Role in development of fixed airway obstruction and chronic obstructive pulmonary disease?

Table 3 : Categorization of severity of asthma

	Mild	Moderate	Severe
Symptoms disturbing sleep	< Once per week	> Once per week	Daily
Daytime symptoms	< Daily	Daily	Daily
Limitation of accustomed activities	Nil	<1 per week	>1 per week
Use of rescue medication *	<1 dose per day	1-2 doses per day	>2 doses per day
FEV1	Normal	60-80%	<60%
Peak expiratory flow	Normal	60-80%	<60%

A patient should be placed in the highest category of severity based on any one of the clinical features or lung function test.

FEV1 Forced expiratory volume in first second

* Each rescue medication dose = 200 µg inhaled salbutamol = 500 µg terbutaline = 2 mg oral salbutamol = 2.5 mg oral terbutaline.

Table 4. Equivalent doses of inhaled corticosteroids (in micrograms/day)

Drug	Low-dose ICS		Medium-dose ICS		High-dose ICS
	Adults	Children	Adults	Children	Adults	Children
Beclomethasone	200-400	100-200	400-1000	200-400	>1000	>400
Budesonide	200-400	100-200	400-800	200-400	>800	>400
Fluticasone	125-250	50-125	250-500	125-250	>500	>250

Medication inserts for hydrofluoroalkane (HFA) preparations should be carefully reviewed for the correct dosage level. In general, the dose of dry powder inhalers with filler (such as lactose) is double than that of pressurized metered dose inhalers.

Table 5. Management of asthma in different stages

Stage	Daily controller medications	Other treatment options
Mild	Low-dose ICS*	Sustained-release theophylline or Cromones
Moderate	Moderate dose ICS + inhaled LABA** and/or LTRA	- Moderate dose ICS + either sustained-release theophylline or LTRA or oral LABA - High-dose ICS
Severe	High dose ICS + inhaled LABA plus one or more of the following if needed: sustained-release theophylline, leukotriene modifiers, oral LABA, oral glucocorticoid

At all steps of severity SABA can be added on as needed basis for symptom relief.
See text for additional details
* Inhaled LABA optional; ** Optional in children
ICS Inhaled corticosteroids; LABA Long-acting beta-2 agonist; LTRA Leukotriene receptor antagonists, SABA Short acting beta-2 agonists

Table 6. Dosages of different anti-asthma drugs

	Adult	Children
Long-acting beta-2 agonists
pMDI/DPI
Salmeterol	50-100 µg/day	50-100 µg/day (>5 years)
Formoterol	12-24 µg/day	12-24 µg/day (>5 years)
Oral
Bambuterol	10-20 mg/day	-
Systemic steroids
Prednisolone
For acute exacerbations	40-60 mg/day for 7-10 days in single or divided doses	1-2 mg/kg/day for 3-10 days in single or divided doses
For long-term control	Administer lowest dose required to control symptoms Preferably single a.m. dose; alternate day if possible	Administer lowest dose required to control symptoms Preferably single a.m. dose; alternate day if possible
Intravenous Hydrocortisone
For acute exacerbations	100 mg stat and 50 mg q6 hourly	4-8 mg/kg/day
Theophyllines	Starting dose 10mg/kg/day (max. 300 mg/day); usual maximum 600-800 mg/day	Starting dose 10mg/kg/day; usual maximum dose age > 1 year- 16 mg/kg/day age < 1 year- [0.2 (age in weeks) + 5] mg/kg/day
Leukotriene modifiers
Montelukast	10 mg/day	2-5 years 4 mg/day
		6-14 years 5 mg/day
Short-acting beta-2 agonists
Salbutamol
pMDI/DPI	100-200 µg/dose	100 µg/dose
Nebulized	2.5 to 5 mg q 4-6 hourly	0.05 mg/kg/dose, (min. 1.25 mg, max. 2.5 mg) q 4-6 hourly
Oral	2-8 mg q 6-8 hourly	1-4 mg q 6-8 hourly
Intravenous	3-20 µg/minute adjusted to bronchospasm and heart rate	0.1-0.2 µg/kg/minute adjusted to bronchospasm and heart rate
Subcutaneous	8 µg/kg	Not recommended
Terbutaline
pMDI/DPI	250 µg/dose	250 µg/dose
Nebulized	10 mg q 4-6 hourly	0.3 mg/kg/dose, (max. 10 mg/dose) q 4-6 hourly
Oral	2.5 mg q 6-8 hourly	0.25 µg/kg/dose q 6-8 hourly (Not recommended below 2 y of age)
Intravenous/Subcutaneous/ Intramuscular	0.25-0.5 mg q 4-6 hourly	10 µg/kg/dose (max. 300 µg)
Anticholinergic drugs
Ipratropium
pMDI/DPI	20 µg/dose	20 µg/dose
Nebulized	0.25 mg q 4-6 hourly	0.25 mg q 4-6 hourly
Tiotropium (pMDI/DPI)	12 µg/day

DPI Dry powder inhaler; pMDI Pressurized metered dose inhaler