Table 1

Characteristics of the study population

Characteristic	All interviewed (n=699)	All, high quality (n=659)	Without premonitory symptoms (n=399)	With premonitory symptoms (n=260)
Male	49.9	49.5	48.9	50.4
45–60 years	77.2	76.8	78.2	74.6
Married	76.3	76.3	78.2	74.2
Socioeconomic group
Manual worker	28.6	28.6	29.4	27.2
Non-manual	60.6	60.3	59.7	61.2
Self-employed	10.8	11.1	10.9	11.6
Hypertension1-150	31.7	31.3	30.3	32.9
Diabetes mellitus	14.5	13.7	12.7	15.4
Smoking1-151
Never	24.3	25.0	24.0	26.4
Former	28.4	28.5	28.4	28.6
Current	47.2	46.6	47.5	45.0
Obesity1-152	43.3	43.2	42.8	43.8
Physically inactive	53.2	52.5	51.8	53.9

Values are percentages.
↵1-150 Hypertension defined as systolic pressure ⩾ 170 mm Hg or diastolic pressure ⩾ 95 mm Hg.
↵1-151 Former smoker defined as having stopped smoking more than two years ago.
↵1-152 Obesity defined as a body mass index of ⩾ 27.