Cardiac Autonomic Reactivity Tests in Type A and Type B Personalities

BACKGROUND: A considerable link between personality types and cardiovascular diseases (CVDs) has been seen. Autonomic responses in both type A and type B personality individuals were found to be influenced by their personality traits. The study suggests further research on cardiac autonomic functions in larger sample sizes and the use of non-invasive screening techniques like cardiovascular reflex tests to stratify participants' risk of future illness. OBJECTIVE: This study aimed to assess autonomic stress reactivity tests in type A and type B personalities using cardiovascular reflex tests. METHODS: This study was conducted at the Department of Physiology, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi. The Hunter-Wolf Personality Questionnaire Scale was used to identify 60 adults, 30 of whom were classified to have type A personality and 30 have type B personality, from the psychiatry department. Autonomic function tests, such as the handgrip tests, cold pressor test, deep breathing test (DBT), lying-to-standing test (LST), and Valsalva maneuver, were performed and recorded for each subject. IBM SPSS Statistics for Windows, version 21 (released 2012; IBM Corp., Armonk, New York, United States) was used for the compilation and analysis of data. RESULTS: The E:I (expiration-to-inspiration) ratio and delta heart rate of the type A personality patients both significantly decreased (p = 0.000*) as compared to the type B personality patients (1.18 ± 0.03 versus 1.25 ± 0.77 and 1.18 ± 0.03 versus 1.25 ± 0.77). The Valsalva ratio of the type A personality patients decreased (1.38 ± 0.10) as compared to the type B personality patients (1.48 ± 0.18), which was statistically significant (p = 0.001*). The 30:15 ratio in the type A personality patients was significantly decreased (p = 0.03*) compared to the type B personality patients (1.12 ± 0.05 versus 1.15 ± 0.10). The handgrip test and cold pressor test results were statistically insignificant. CONCLUSION: Compared to the type B personality patients, which exhibited an increase in both parasympathetic and sympathetic reactivity, the type A personality patients exhibited a reduction in resting cardiovascular parameters and resting autonomic tone. Consequently, in order to stratify the participants' risk of future illness, we recommend employing non-invasive procedures, such as cardiovascular reflex tests, as a screening technique.