Investigation of autonomic dysfunction in primary Raynaud’s phenomenon with sympathetic skin response (SSR), R-R interval variation (RRIV) and composite autonomic symptom score (COMPASS)-31

Background: In this study, we aimed to investigate the autonomic dysfunction in patients with primary Raynaud’s phenomenon with using sympathetic skin response (SSR) as a neurophysiologic test, R-R interval variation analysis and composite autonomic symptom score (COMPASS)-31 questionnaire. Methods: Palmar SSR to median nerve electrical stimulation was recorded in 38 patients with 36 healthy age and sex-matched control subjects. The SSR was recorded from the palmar surface of both left and right hands for patients and control groups. The amplitudes and latencies formed as a result of electrical stimulation were calculated and compared between the two groups. Additionally, R-R interval variability was examined during normal breathing, deep breathing, standing up and Valsalva maneuver in both groups. Furthermore, we asked to complete the COMPASS-31 questionnaire, a validated tool to assess symptoms of autonomic dysfunction. And by calculating total COMPASS-31 scores, the relationship between the two groups was investigated. Results: The Raynaud’s phenomenon and control groups were similar in age (37.4 ± 11.6 vs. 34.9 ± 13.0 years), had identical gender ratios and similar body mass index (24.5 ± 6.1 vs. 25.7 ± 4.6%). Palmar SSR to median nerve stimulation of RP patients shows significantly delayed latency (1890 ± 146) (p=0.03). And no difference between amplitudes in comparison to the control group. In the patient and control groups, R-R interval measurements were evaluated during rest and deep breathing, standing up and Valsalva maneuver. When the R-R interval measurements of the patient and control groups at rest and deep breathing were compared, there was no statistically significant difference between the groups. In addition, COMPASS-31 questionnaire scoring system was applied to both groups. The mean COMPASS-31 score was higher in patient group (22.8 ± 13.8), than from healthy controls (8.9 ± 7.8) (p=0.02) Conclusions: Autonomic dysfunction plays a role in the etiology of Raynaud’s phenomenon, due to latency prolongation in the sympathetic skin response and significant difference between COMPASS-31 tests, and these tests can be used in the diagnosis stage of this disease.