Association of Blood Pressure with Suicide Attempt in First-Episode Drug-Naive MDD: Anxiety Mediates

This study investigated the relationships between blood pressure parameters and suicide attempt risk in first-episode, drug-naive major depressive disorder (MDD) patients, and examined anxiety's mediating role. Blood pressure parameters were measured in 1,718 first-episode, drug-naive patients with MDD. Relationships with suicide attempt risk were analyzed using logistic regression with curve fitting and threshold effect analysis. Mediation analysis assessed anxiety's role. A U-shaped relationship existed between pulse pressure (PP) and suicide attempt risk (inflection point: 43 mmHg). Below this threshold, each 1 mmHg PP increase was associated with 6.5% lower risk (OR = 0.935, 95% CI: 0.897-0.974); above it, each 1 mmHg increase was associated with 7.1% higher risk (OR = 1.071, 95% CI: 1.036-1.107). Systolic (SBP) and diastolic blood pressure (DBP) showed J-shaped relationships with suicide risk (inflection points: 132 mmHg and 77 mmHg, respectively). No significant associations existed below these thresholds, while above them, each 1 mmHg increase in SBP and DBP was associated with 21.9% (OR = 1.219, 95% CI: 1.144-1.299) and 9.0% (OR = 1.090, 95% CI: 1.049-1.132) higher suicide attempt risk, respectively. Anxiety partially mediated the effects of PP (29.34%), SBP (31.89%), and DBP (35.75%) on suicide risk. Blood pressure parameters, particularly elevated SBP and DBP, significantly predict suicide attempt risk in MDD patients, with anxiety playing a partial mediating role. These findings highlight the importance of blood pressure monitoring and anxiety management in suicide prevention strategies for MDD patients.