Trait anxiety is associated with blood pressure and muscle sympathetic nerve activity

Abstract

Heightened anxiety is associated with an increased risk for cardiovascular diseases such as coronary heart disease and hypertension. While hyperactivity of the sympathetic nervous system has been suggested to mediate this relationship, direct measures of muscle sympathetic nerve activity (MSNA) in people with elevated anxiety have indicated little, if any, alterations in baseline sympathetic function. However, studies examining anxiety and MSNA have been limited by small sample sizes and lack of detail on anxiety severity, limiting the ability to investigate subtle interactions. The present study assessed associations between trait anxiety, mean arterial pressure (MAP), and MSNA using a large, representative sample of healthy young men and women, with an exploratory assessment of sex-specific interactions. We hypothesized that heightened trait anxiety would be associated with elevated resting MAP and MSNA. Trait anxiety was assessed using the Spielberger Trait Anxiety Inventory (STAI) in 97 healthy adults (52 male, 45 female; 25±1 years; 26±1 kg/m 2 ). In each participant, the average of three seated brachial blood pressures was recorded and used in subsequent analysis. All participants underwent an autonomic function test that simultaneously assessed heart rate (HR), beat-to-beat blood pressure, MSNA burst frequency (BF) and incidence (BI) during 5-10 minutes of supine rest. MSNA recordings were captured in 91 participants. Multiple regression was used to test the relationship between STAI, MAP, MSNA, and HR while accounting for age and sex. Sex-specific interactions were explored with correlations controlling for age. The regression model significantly predicted MAP (R 2 =.196, P<0.001), BF (R 2 =.136, P=0.005), and BI (R 2 =.150, P=0.003), but not HR (R 2 =.055, P=0.155). STAI scores were independently associated with MAP (β=.207, P=0.029), BF (β=.245, P=0.016), and BI (β=.224, P=0.027). In males, STAI was correlated with MAP (R=.277, P=0.049), BF (R=.363, P=0.009), and BI (R=.346, P=0.013), but not HR (R=.140, P=0.326). In contrast, STAI was not associated with MAP (R=.174, P=0.260), BF (R=.094, P=0.574), BI (R=.069, P=0.681), or HR (R=.226, P=0.141) in females. In a large sample of healthy adults, our results highlight the relationship between the severity of trait anxiety, resting blood pressure, and sympathetic outflow, with a more pronounced relationship in males. Support: NIH (AA-024892, 1R15HL140596-01, AG064038-01A1, U54GM115371; P20GM103474, 2TL1 TR002318). This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.