Association between depression and hypertension using classic and revised blood pressure thresholds

In a primary care population, the relationship between treatment of depression and hypertension (HTN) under the recently revised American College of Cardiology and American Heart Association HTN thresholds for diagnosing HTN is unknown.

To compare the association between changes in severity of co-occurring depression and HTN over time using the newly revised versus previous HTN guidelines.

In this retrospective cohort study, outpatients ≥18 years (n = 3018) with clinically significant depressive symptoms and elevated blood pressure at baseline were divided into a 'revised' guideline group (baseline blood pressure ≥130/80 mmHg), a 'classic' guideline group (≥140/90 mmHg) and a 'revised-minus-classic' group (≥130/80 and <140/90 mmHg). Depressive symptom change was assessed using the Patient Health Questionnaire-9 (PHQ-9). Correlations between changes in PHQ-9 scores and HTN levels by group over a 6- to 18-month observation period were assessed using robust regression analysis.

There were demographic and clinical differences between groups. A total of 41% of study subjects (1252/3018) had a visit during the follow-up period where additional PHQ-9 and HTN results were available. Depressive symptom change was unrelated to change in blood pressure in the revised and revised-minus-classic groups. The classic HTN group demonstrated a clinically insignificant change in systolic blood pressure for each unit change in PHQ-9 score (β = 0.23, P-value =0.02).

Although a statistically significant association between reduced HTN levels and improvement in depressive symptoms was demonstrated under classic HTN guidelines, there was no clinically meaningful association between treatment of depression and improved HTN levels under either guideline.