Table 3.

Risk of breast cancer by the age group, observation period and cumulative olanzapine equivalent dose

	Events	Person-Years	Incidence rate (per 100,000 person-years)	HR (95% CI)	pvalue
Age group (yr)
18−44	861	1,035,905	83.12 (77.66−88.86)	1.03 (0.95−1.12)	0.43
45−64	1,509	886,104	170.30 (161.81−179.11)	1.17 (1.09−1.24)	< 0.001
65−79	544	733,384	74.18 (68.07−80.68)	0.93 (0.85−1.03)	0.18
Observation period (yr)
< 3	1,240	1,262,169	98.24 (92.85−103.87)	1.02 (0.95−1.09)	0.66
3 to < 6	848	799,583	106.06 (99.04−113.44)	1.06 (0.97−1.15)	0.18
≥ 6	826	593,641	139.14 (129.81−148.96)	1.24 (1.14−1.35)	< 0.001
Cumulative olanzapine equivalent dose (mg)
< 10,000	2,496	2,394,130	104.25 (100.20−108.43)	1.05 (1.00−1.11)	0.03
≥ 10,000	418	261,263	155.99 (145.02−176.09)	1.29 (1.14−1.46)	< 0.001

HR, hazard ratio; CI, confidence interval.