Job strain and blood pressure in employed men and women: a pooled analysis of four northern italian population samples

OBJECTIVE: The extent to which psychosocial stress concurs to raise blood pressure is still uncertain. Here the association between job strain and office blood pressure in a pooled analysis of four population samples from northern Italy is assessed. METHODS: Four surveys assessing prevalence of major coronary risk factors were performed in 1986, 1990, 1991, and 1993 in area "Brianza" (Milan), a World Health Organization-MONItoring cardiovascular disease (WHO-MONICA) Project collaborating center. Ten year age- and gender-stratified independent samples were randomly recruited from the 25- to 64-year-old residents. The methods used to assess coronary risk factors strictly adhered to the MONICA manual, were kept constant, and underwent internal and external quality controls. Job strain was investigated through the administration to employed participants of a questionnaire derived from the Karasek model, assessing job demand/control latitude. Analysis was restricted to 25- to 54-year-old participants, untreated for hypertension (1799 men and 1010 women). RESULTS: Among men, there was a 3 mm Hg increase of systolic blood pressure (p<.001) moving from low to high strain job categories. This difference was independent from age, education, body mass index, alcohol intake, smoking habits, leisure time physical activity, and survey. No relevant differences among job strain categories were found in women and for diastolic blood pressure in both gender groups. CONCLUSIONS: These results carried out on a large population-based sample confirm previous findings obtained adopting ambulatory blood pressure measurements in more restricted samples of population or patients. Further research is needed to clarify the relationship between perceived work stress and blood pressure in women