Table 2.

Age- and Season-Adjusted Incidence Ratios for Acute Myocardial Infarction (AMI) Occurring After Acute Respiratory Infection (ARI) Overall and by Sex, Age, Infarction Type, and History of Vascular Disease

Model	Adjusted Incidence Ratio (95% Confidence Interval), by Period of Infection Risk in Daysa
	1–3 (n = 52)	Pb	4–7 (n = 44)	8–14 (n = 48)	15–28 (n = 80)	29–91 (n = 262)	Baseline (n = 3441)
Overall	4.19 (3.18–5.53)		2.69 (1.99–3.63)	1.66 (1.24–2.23)	1.41 (1.12–1.77)	1.05 (.92–1.21)	1.00
Sex
Men	4.32 (3.02–6.19)	.82	2.01 (1.28–3.16)	1.28 (.83–1.97)	1.39 (1.03–1.89)	0.99 (.82–1.19)	1.00
Women	4.05 (2.62–6.27)		3.66 (2.45–5.46)	2.22 (1.50–3.29)	1.44 (1.01–2.06)	1.16 (.94–1.43)	1.00
Age, y
<60 y	1.46 (.47–4.55)		1.46 (.54–3.91)	1.88 (.97–3.65)	1.50 (.88–2.56)	0.84 (.59–1.21)	1.00
60–69 y	3.93 (2.15–7.18)	.13c	1.89 (.89–4.00)	1.09 (.51–2.30)	0.96 (.54–1.71)	1.03 (.77–1.38)	1.00
70–79 y	4.14 (2.47–6.95)	.1c	3.55 (2.18–5.78)	2.31 (1.45–3.66)	1.81 (1.23–2.65)	0.96 (.73–1.26)	1.00
≥80 y	5.94 (3.90–9.04)	.023c	3.18 (1.93–5.25)	1.40 (.79–2.48)	1.35 (.88–2.07)	1.31 (1.04–1.66)	1.00
Infarction type
STEMI	4.66 (3.04–7.15)	.53	1.76 (.97–3.21)	1.77 (1.12–2.80)	1.13 (.74–1.71)	0.98 (.78–1.23)	1.00
NSTEMI	3.89 (2.71–5.60)		3.25 (2.30–4.60)	1.60 (1.10–2.33)	1.58 (1.20–2.09)	1.10 (.93–1.31)	1.00
History of vascular disease
No	4.32 (3.10–6.02)	.73	3.00 (2.12–4.25)	1.68 (1.18–2.39)	1.37 (1.03–1.82)	0.99 (.83–1.17)	1.00
Yes	3.89 (2.35–6.42)		2.03 (1.11–3.69)	1.62 (.97–2.72)	1.49 (1.00–2.21)	1.19 (.95–1.51)	1.00

Data are for 8204 ARIs.

Abbreviations: NSTEMI, non–ST-elevation myocardial infarction; STEMI, ST-elevation myocardial infarction.

^a n values denote the no. of AMI events.

^b By the Cochran Q test for heterogeneity between the 2 strata, unless otherwise indicated, during days 1–3.

^c Compared with <60 y.