Respiratory effect of beta-blockers in people with asthma and cardiovascular disease: population-based nested case control study

Table 2 Incidence rate ratios for the association between beta-blocker exposure and asthma exacerbations by dose

	Cardioselective beta-blockers						Non-selective beta-blockers
	Exposed	Exposed	Crude	Adjusted			Exposed	Exposed	Crude	Adjusted
	cases^a	controls^a	IRR	IRR	95% CI	P value	cases^a	controls^a	IRR	IRR	95% CI	P value
Any exposure
Severe exacerbation	27	466	0.72	0.87	0.57–1.35	0.540	9	51	1.29	1.66	0.53–5.35	0.398
Moderate exacerbation	357	3956	0.89	0.97	0.85–1.11	0.658	35	309	1.33	1.41	0.95–2.08	0.088
Low dose
Severe exacerbation	23	388	0.70	0.85	0.53–1.36	0.501	8	44	1.04	1.19	0.31–4.53	0.799
Moderate exacerbation	283	3256	0.87	0.96	0.83–1.10	0.544	29	271	1.19	1.24	0.80–1.91	0.336
High dose
Severe exacerbation	4	82	0.85	0.96	0.33–2.84	0.943	1	7	5.00	12.11	1.02–144.11	0.048
Moderate exacerbation	79	733	0.99	1.08	0.82–1.42	0.600	6	39	2.50	2.67	1.08–6.62	0.034

^aExposed cases/controls, exposed within the 60 day risk window
IRR Incidence Rate Ratios
Adjusted for asthma medication use in the 90 days prior to the index date; respiratory tract infection in the 90 days prior to the index date; prior hospitalization for asthma; type of CVD medicine use in the year prior to the index date; exact age; smoking status; body mass index; social deprivation; Charlson comorbidity index; and primary care asthma review in the year prior to the index date

ISSN: 1741-7015