Table 3

IR of ischaemic heart disease per 1000 person-years, for patients with and without COPD, per age category

Age	Without COPD				With COPD				IRR	95% CI
Age	IR	95% CI	Cases	Person-time	IR	95% CI	Cases	Person-time	IRR	95% CI
Males
≤64	4.91	4.61 to 5.21	1019	207 717.3	11.17	8.40 to 14.57	51	4565.8	2.28	1.79 to 3.02
65–74	12.88	11.82 to 14.01	543	42 166.7	16.56	12.56 to 21.45	54	3260.7	1.29	1.21 to 1.42
≥75	15.17	13.27 to 17.26	222	14 638.3	21.08	14.99 to 28.87	36	1707.4	1.39	0.98 to 1.98
Females
≤64	2.50	2.30 to 2.72	523	209 338.7	11.33	8.72 to 14.48	60	5295.4	4.56	3.47 to 5.92
65–74	7.58	6.86 to 8.36	396	52 235.4	13.90	10.43 to 18.18	50	3596.5	1.83	1.37 to 2.46
≥75	10.01	8.75 to 11.40	219	21 876.3	12.62	8.19 to 18.63	23	1822.9	1.26	0.82 to 1.94
Total study population
≤64	3.70	3.52 to 3.89	1542	417 056.0	11.26	9.30 to 13.50	111	9861.1	3.04	2.51 to 3.69
65–74	9.95	9.33 to 10.60	939	94 402.1	15.17	12.45 to 18.30	104	6857.1	1.53	1.25 to 1.87
≥75	12.08	10.99 to 13.24	441	36 514.6	16.71	12.84 to 21.41	59	3530.3	1.38	1.06 to 1.82

IR per 1000 person-years. Person-time in years.
COPD, chronic obstructive pulmonary disease; IR, incidence rate; IRR, IR ratio.