Mental stress may lead to activation of the inferior frontal lobe in the brain leading to angina in patients with coronary artery disease (CAD), find researchers from Emory University, Atlanta. The study has been published recently in the journal Circulation: Cardiovascular Imaging.
The inferior frontal lobe plays a pivotal role in stress regulation. Increased activation of the lobe can incite a severe stress reaction.
The researchers conducted a study to find the correlation between activation of the inferior frontal lobe with stress and angina in individuals with CAD.
The study analysed 148 individuals with CAD. Individuals with stable coronary artery disease underwent acute mental stress testing using a series of standardised speech/arithmetic stressors in conjunction with high-resolution positron emission tomography imaging of the brain.
Blood flow to the inferior frontal lobe was evaluated as a ratio compared with the whole-brain flow for each scan. Angina was assessed with the Seattle Angina Questionnaire angina frequency subscale at baseline and 2 years follow-up. For every doubling in the inferior frontal lobe activation, angina frequency was increased by 13.7 units at baseline (P=0.008) and 11.6 units during follow-up (P=0.01) in a model adjusted for baseline demographics.
The inferior frontal lobe activation due to mental stress was positively associated with angina at baseline and follow-up. Mental stress-induced ischemia and activation of other brain pain processing regions like thalamus, insula, and amygdala accounted for 40.0% and 13.1% of the total effect of inferior frontal lobe activation on angina severity, respectively.
The researchers added that mental stress-induced ischemia and other pain-processing brain regions may also play a contributory role in the findings.