Depression, a prevalent mental disorder, frequently co-occurs with physical illnesses. It's recognized as a risk factor for cardiovascular diseases (CVD) and is associated with a poorer prognosis. This link is partly explained by the increased presence of CVD risk factors in individuals with depressive symptoms, such as obesity, poor diet, inactivity, smoking, and inadequate medication adherence. Furthermore, mental stress disrupts the autonomic nervous system (ANS) and adrenocortical hormone regulation, potentially contributing to CVD. Hypertension (HT), a significant risk factor for CVD, is also influenced by depression, anxiety, stress, and personality traits. However, the precise relationship between depression and HT remains unclear, with studies showing both positive and negative associations. A key reason for this inconsistency may be the reliance on office blood pressure (BP) measurements in many past studies. Office BP measurements can be less reproducible and less accurately predictive of cardiovascular diseases than home BP measurements. Home BP, measured in a familiar environment, is more reproducible and a better predictor of CVD. Home BP measurement also allows for both morning and evening readings, providing a more comprehensive picture of BP patterns. This study aimed to clarify the association between depressive symptoms and the development of home HT by using home BP measurements. The hypothesis was that a positive correlation exists between depressive symptoms and new-onset home HT. The study also assessed both research center BP and home BP to see if depressive symptoms impacted them differently.

The literature regarding the relationship between depression and hypertension is mixed, with some studies reporting a positive association and others reporting a negative association or no association. This inconsistency may be attributed to the use of office blood pressure measurements in many previous studies, which are known to be less reliable than home blood pressure measurements in predicting cardiovascular events. The authors cite several studies that support both positive and negative correlations between depression and blood pressure, highlighting the need for a more comprehensive investigation using home blood pressure monitoring.

This prospective cohort study utilized data from the Tohoku Medical Megabank Community-Cohort Study in Miyagi Prefecture, Japan. Participants (n=3082) with home normotension (SBP <135 mmHg and DBP <85 mmHg) at baseline were included. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale-Japanese version (CES-D) at baseline. A secondary survey, approximately 4 years later, evaluated the onset of home HT (SBP ≥ 135 mmHg or DBP ≥ 85 mmHg). Home BP was measured using an electronic upper arm cuff device (HEM-7080IC; OMRON Corp.) twice daily (morning and evening) for 2 weeks at baseline and 10 days at the secondary survey. Research BP was measured at a research center using a different device (HEM-9000AI; OMRON Corp.). Other data collected included demographic information, lifestyle factors (smoking, drinking, exercise), medical history, Athens Insomnia Scale (AIS) score, educational level, and the impact of the 2011 Great East Japan Earthquake. Statistical analyses included t-tests, Mann-Whitney U-tests, Chi-square tests, and multivariate logistic regression models to determine the odds ratios (ORs) of developing home HT (overall, morning, and evening) associated with depressive symptoms. Subgroup analyses were performed based on age, sex, BP pattern (normotension vs. white coat hypertension), and drinking habit. Sensitivity analyses were conducted excluding participants with treated HT at the secondary survey.

The study included 3082 participants (mean age: 54.2 years; 80.9% female). 23.7% had depressive symptoms at baseline. During the 3.5-year follow-up, 17.0% of participants with depressive symptoms and 16.5% of those without developed home HT. Multivariable adjusted odds ratios showed a significant positive association between depressive symptoms and the risk of developing home HT (OR 1.37, 95% CI 1.02-1.84), particularly evening HT (OR 1.66, 95% CI 1.17-2.36). The association between depressive symptoms and morning HT was not statistically significant (OR 1.18, 95% CI 0.86-1.61). Subgroup analyses showed that this association was consistent across different age groups, sexes, BP patterns, and drinking habits. For women and non-drinkers, the odds of developing home and evening HT were significantly increased in the presence of depressive symptoms. In participants with normotension at baseline, depressive symptoms were significantly associated with evening HT.

This study provides evidence of a positive association between depressive symptoms and the development of new-onset home HT, particularly evening HT, in individuals with home normotension at baseline. This finding is consistent across various subgroups and highlights the importance of considering depressive symptoms as a potential risk factor for HT development. The use of home BP monitoring, which offers higher reproducibility and predictive accuracy compared to office BP, strengthens the study's findings. The stronger association observed for evening HT suggests potential underlying mechanisms involving circadian rhythms and the influence of stress on BP regulation. These findings underscore the need for comprehensive assessment of both mental and physical health in individuals, particularly when considering the management of HT.

This prospective cohort study demonstrated a significant association between depressive symptoms and the increased risk of developing home hypertension, particularly evening hypertension. These findings suggest the importance of incorporating mental health assessments into routine hypertension screening and management, especially in individuals with home normotension. Further research is needed to investigate the underlying mechanisms of this association and to explore potential interventions to mitigate the risk of hypertension among individuals with depressive symptoms. The use of home blood pressure monitoring is recommended for early detection and intervention.

The study's limitations include the potential for residual confounding despite multivariable adjustment. The cross-sectional nature of the baseline data does not allow causal inference. The study's reliance on self-reported data may introduce biases, although validated instruments were used. The study population was predominantly Japanese, limiting the generalizability to other populations. Finally, the mechanisms underlying the observed relationship between depressive symptoms and hypertension were not directly explored, representing an area for future investigation.