Genetic causal assessment between major depression and hypertension: A two-sample bidirectional Mendelian randomization study.

Objective: The concurrent prevalence of major depression and hypertension represents a significant clinical concern. This study aims to investigate the potential causal relationship among these conditions from a genetic standpoint.

Methods: The genome-wide association studies (GWAS) summary data for major depression were obtained from the IEU OpenGWAS database. Concurrently, GWAS summary data for hypertension were sourced from the Finnish consortium. All the participants have European ancestry. A two-sample bidirectional Mendelian randomization (MR) study was conducted to examine the relationship between major depression and hypertension. To ensure the reliability of the results, several sensitivity analyses were performed, addressing heterogeneity, horizontal pleiotropy, outliers, the influence of individual single nucleotide polymorphisms (SNPs), and adherence to normal distribution assumptions.

Results: The findings revealed a significant positive genetic causal association between major depression and hypertension (P = 0.016, odds ratio [OR] = 1.160, 95% confidence interval [CI] = 1.029-1.308). Conversely, no genetic causal relationship was identified between hypertension and major depression (P = 0.670, OR = 1.004, 95% CI = 0.985-1.024). Our MR analysis indicated the absence of heterogeneity and horizontal pleiotropy, with no detected outliers. Additionally, the analysis was not influenced by any SNP and demonstrated a normal distribution.

Conclusion: The results of this study indicate that severe depression is a risk factor for hypertension of European ancestry. The conclusion of this study should be used with caution when applied to other populations. Clinically depressed patients should be closely monitored for the onset of hypertension.