Table 4. Multivariate model for risk of admission for children (5–17 years) and for adults (18–75 years).

	Children (5–17) Na=6,853			Adults (18–75) Na=28,992
	OR	95% CI	P value	OR	95% CI	P value
Gender
Male (ref)	1			1
Female	1.36	(0.98–1.89)	0.07	1.34	(1.03–1.75)	0.03
Age	0.85	(0.81–0.90)	<0.00	0.98	(0.97–0.99)	0.00
Ethnicityb
White (ref)	1			1
South Asian	1.47	(0.83–2.62)	0.19	1.83	(1.36–2.47)	<0.00
Black	1.21	(0.61–2.40)	0.58	2.30	(1.64–3.23)	<0.00
Flu immunisationc
No (ref)	1			1
Yes	1.01	(0.75–1.38)	0.93	1.03	(0.74–1.43)	0.85
Currently smoking
No (ref)	NA			1
Yes	NA	NA	NA	0.83	(0.61–1.12)	0.23
COPD diagnosis
No (ref)	NA			1
Yes	NA	NA	NA	0.99	(0.59–1.68)	0.98
SABA inhalers prescribed
1–3 (ref)	1			1
0	1.03	(0.25–4.36)	0.96	0.81	(0.37–1.78)	0.60
4–12	1.66	(1.13–2.43)	0.01	1.71	(1.20–2.46)	<0.00
13+	4.09	(2.01–8.34)	<0.00	3.22	(2.04–5.07)	<0.00
Asthma severity
Step 1 (ref)	1			1
Step 2	1.30	(0.76–2.24)	0.33	1.24	(0.79–1.97)	0.35
Step 3	2.73	(1.41–5.28)	<0.00	2.90	(1.79–4.69)	<0.00
Step 4/5	5.54	(1.50–20.51)	0.01	9.42	(5.27–16.84)	<0.00
GP consultation rate per patient
0–1 (ref)	1			1
2–6	1.32	(0.92–1.90)	0.13	1.59	(0.99–2.57)	0.06
>6	2.58	(1.43–4.66)	<0.00	2.80	(1.70–4.63)	0.00

Adjusted for IMD2010 quintile, total ICS+COMBI inhalers and practice clustering.

Abbreviations: CI, confidence Interval; COMBI, combination inhalers (ICS and long-acting β₂-agonist); COPD, chronic obstructive pulmonary disease; ICS, inhaled corticosteroid; OR, odds ratio; NA, not applicable; SABA, short-acting β₂-agonist.

^aN=cases contributing to the model.

^b'Other' and 'unknown' ethnicity categories not shown.

^cFlu immunisation in the past year.