141. Heart rate variability in spinocerebellar ataxia type 2

Abstract

Ninety seven SCA2 patients, who had genetic positive test results, were submitted to the standardized clinical autonomic Scale for Outcomes in Parkinson’s disease (SCOPA-AUT) and to HRV testing (resting condition). Time and frequency domain HRV measures were obtained; all indexes were compared (tStudent, p < 0.05) with those of 97 healthy subjects (age and sex matched) used as a control group. SCA2 patients showed significantly more symptoms than subjects in the control healthy group, mainly referred to gastrointestinal and urinary systems. HRV measures in the time domain (mean cardiac period, range, standard deviation, root mean square of successive differences and the triangular index of RR intervals) and frequency domain indexes (spectral power density of the low [LF], medium [MF] high [HF] and total frequency range) were significantly lower in SCA2 patients. The autonomic stress index and the frequency LF/HF ratio were increased in SAC2 patients. On the other hand, normalized measures of the power spectral density (%) showed that the main reduction in the 0.04–0.15 spectral frequency range was observed for frequencies in the 0.1–0–15 range, intimately related with the arterial pressure Mayer waves. Detected differences in all cases were statistically significant for p level < 0.001. We suggest a definite autonomic dysfunction in the group of patients. This report is the first one showing autonomic dysfunction in SCA subjects genetically diagnosed.