Table 2. Incidence of Kidney Failure by Smoking Status in Singapore Chinese Health Study.

	All	Men ever smoker (years of smoking)				Women ever smoker(years of smoking)
		Never smoker	> = 40 years	20–39 years	< = 19 years	Never smoker	> = 40 years	20–39 years	< = 19 years
Persons	63163	11706	5491	8467	2243	32153	1290	1274	539
Person-years	774434.1	144629.2	56769.7	102753.7	27097.8	407116.6	14116.4	15498.4	6452.3
Median of follow-up	13.3	13.3	11.3	13.2	12.6	13.6	11.9	13.4	12.7
Kidney Failure (N)	674	116	72	89	27	327	15	21	7
Incidence rate per 1000 py	0.870 (0.805–0.936)	0.802 (0.656–0.948)	1.268 (0.975–1.561)	0.866 (0.686–1.046)	0.996 (0.621–1.372)	0.803 (0.716–0.890)	1.063 (0.525–1.600)	1.355 (0.775–1.934)	1.085 (0.281–1.889)