Table 3

Multivariate-adjusted HRs and 95% CIs of first CHD event, for HS versus no HS (reference category), among non-manual and manual workers only

	Non-manual workers				Manual workers
	N	#CHD	HR	95% CI	N	#CHD	HR	95% CI	p Value*
Job strain categories
All events in the entire follow-up period
No HS	1067	32	REF		1258	37	REF		0.7
HS	399	17	1.70	0.94 to 3.08	560	22	1.94	1.13 to 3.32	0.7
Events occurred after the first 3 years of follow-up
No HS	1058	27	REF		1247	34	REF		0.7
HS	394	14	1.68	0.88 to 3.23	553	20	1.95	1.11 to 3.43	0.7

MONICA Brianza, PAMELA and SEMM cohorts. Men were 25–64 years old and employed at time of recruitment.
HRs estimated from Cox regression models with age as the time scale, adjusted for study type (population-based vs factory-based), systolic blood pressure, total cholesterol, HDL cholesterol, diabetes and current smokers. Job strain categories are based on items of Psychological Job Demand and Decision Latitude.
*p Value for interaction test between occupational class and high strain (1 df Wald χ² test).
CHD, coronary heart disease; HDL, high-density lipoprotein; HS, high job strain; no HS, non-high job strain; PAMELA, Pressioni Arteriose Monitorate E Loro Associazioni; SEMM, Surveillance of Employees of the Municipality of Milan.