Avaliação da reatividade cardiovascular em pacientes com esclerose múltipla

Abstract

Introduction: Multiple Sclerosis (MS) is a chronic inflammatory disease characterized by the presence of demyelinating, inflammatory, and degenerative multifocal central nervous system (CNS) lesions. MS is the most common non traumatic disease causing neurological sequelae in young adults, thus having a high social burden. Since there is a diffuse CNS involvement, it is expected that the areas related with the regulation of cardiovascular reactivity may be affected, thus impairing the autonomic reactivity to different stimuli. Studies have identified the presence of cardiovascular autonomic reactivity in MS patients; however, there are not previous studies evaluating the cardiovascular reactivity to cold and to mental stress. Objective: To evaluate cardiovascular autonomic reactivity to cold and mental stress in MS patients. Materials and Methods: This is a sectional, case-control study. Twenty three MS patients and twenty-three healthy volunteers were included. Patients and controls were submitted to the Beck depression and anxiety inventories (BDI and BAI), and two stress triggered autonomic reactivity tests: the Stroop test (reactivity to mental stress) and cold pressure test (CPT) (reactivity to cold stimulus). The variation of systolic blood pressure (SBP), diastolic (DBP), and heart rate (HR) were measured in rest and active phase which one and with two minutes. Mean and standard deviation were used for descriptive data. Normality verification was carried out with the Kolmogorov-Smirnov test. To compare means between groups the Student's t test was used. Analysis of variance of SBP, DBP and HR tests of patients and controls at different stages (rest, in active phase with 1 and 2 minutes) was performed using two-tailed ANOVA followed by Bonferroni multiple correlations test. Results: The mean age of patients was 34.39 ± 8.85 years, the mean EDSS was 2.409±0.97. The patients BDI index was 8.348 ± 4.783 and controls was 6.826 ± 3.798, with no statistical difference. Mean patients BAI was 12.57 ± 6.795 and controls was 10.17 ± 7.184, without statistical significant differences. The PAD (1 minute) minus the PAD (rest) of patients in the Stroop test was 10.39 ± 4.435. The PAD (1 minute) minus the PAD (rest) of controls on the Stroop test was 11.35 ± 11.06. This difference was significantly different (P = 0.01), being lower in patients. HR (1 minute) minus HR (rest) of patients in the Stroop test was -3.30 ± 16.96. HR (1 minute) minus HR (rest) of controls on the Stroop test was 11.23 ± 7.17. This difference was significantly lower in patients than in controls (P = 0.016). There were no statistical differences with the other comparisons. Conclusion: In our study, the cardiovascular response in MS patients was different from the controls with the Stroop test. This is an easy to perform and with negligible discomfort test. This finding is in line with previous data showing involvement of the cardiovascular reactivity in this disease. The presence of differences in the Stroop reactivity and not with CPT suggests that neurologic pathways exclusively related to the first, such as orbitofrontal, the insula, and the anterior cingulate cortex may be involved in MS. Also, this finding suggests that this test can be useful in the evaluation of patients at high cardiovascular risk, allowing more careful attention with the use of drugs with cardiovascular effects.