Prospective data on depressive symptoms and blood pressure (BP) are scarce, and the impact of age on this association is poorly understood.

The present study examines longitudinal trajectories of depressive episodes and the probability of hypertension associated with these trajectories over time.

Participants were 6,889 men and 3,413 women London based civil servants followed for 24 years between 1985 and 2009. The age of participants over the follow-up ranged from 35 to 80 years. Depressive episode (defined as scoring 4 or more on the General Health Questionnaire-Depression subscale or using prescribed antidepressant medication) and hypertension (systolic/diastolic blood pressure ≥ 140/90 mm Hg or use of antihypertensive medication) were assessed concurrently at five medical examinations.

In longitudinal logistic regression analyses based on Generalized-Estimating-Equation using age as the time scale, participants with depression trajectory characterised by increasing depressive episodes overtime had a greater increase in the likelihood for hypertension with advancing age; an adjusted-excess increase of 7% (95% CI 3-12, p < 0.001) for each five-year increase in age compared to those with a low/stable depression trajectory. In a model adjusted for relevant confounders, a higher risk of hypertension in the first group of participants did not become evident before age 55. A similar pattern of association was observed in men and women although the association was stronger in men.

This study suggests that the risk of hypertension increases with repeated experience of depressive episodes over time and materializes in later adulthood.