TABLE 2—
Differences in Blood Pressure at Follow-Up and Risk Ratios for Blood Pressure Increases in the Highest Quintile Group: Cumulative Job Strain Categories Compared With the Never-Exposed Category: Quebec City, 1991–2003
| Systolic Blood Pressure, Adjusted (95% CI) | Diastolic Blood Pressure, Adjusted (95% CI) | |
| Difference in blood pressure at follow-up, mm Hg | ||
| Men | ||
| Never exposed | 119.7 | 77.7 |
| Exposed only at baseline | 1.0 (–0.0, 2.0) | 0.8a (0.0, 1.5) |
| Exposed only at follow-up | 1.5a (0.2, 2.8) | 0.6 (–0.3, 1.5) |
| Exposed at baseline and follow-up | 1.8a (0.1, 3.5) | 0.8 (–0.5, 2.0) |
| Women | ||
| Never exposed | 119.1 | 75.5 |
| Exposed only at baseline | 0.1 (–0.9, 1.1) | 0.3 (–0.5, 1.0) |
| Exposed only at follow-up | 0.2 (–0.9, 1.4) | –0.1 (–0.9, 0.8) |
| Exposed at baseline and follow-up | 0.5 (–0.8, 1.8) | 0.5 (–0.5, 1.4) |
| Risk ratio for blood pressure increase in highest quintile | ||
| Men | ||
| Never exposed | 1.0 | 1.0 |
| Exposed only at baseline | 0.98 (0.81, 1.18) | 1.06 (0.90, 1.24) |
| Exposed only at follow-up | 1.40b (1.14, 1.73) | 1.10 (0.92, 1.32) |
| Exposed at baseline and follow-up | 1.33b (1.01, 1.76) | 1.07 (0.84, 1.36) |
| Women | ||
| Never exposed | 1.0 | 1.0 |
| Exposed only at baseline | 1.10 (0.94, 1.29) | 1.08 (0.92, 1.28) |
| Exposed only at follow-up | 1.10 (0.91, 1.32) | 0.91 (0.74, 1.12) |
| Exposed at baseline and follow-up | 1.15 (0.93, 1.41) | 1.06 (0.85, 1.31) |
Note. CI = confidence interval. Adjusted models included the following covariates: age, body mass index, social support at work, living with a child, number of years working for the organization, and baseline systolic or diastolic blood pressure values. a Statistically significant difference (P < .05) compared with never-exposed group according to F and t statistics obtained from analysis of covariance. bStatistically significant risk ratio (P < .05) compared with never-exposed group according to overall χ2 statistic obtained from binomial regression analysis.