RESUMO
OBJECTIVES: To explore and quantify possible abnormalities in the autonomic cardiovascular regulation in presymptomatic stage of type 2 spinocerebellar ataxia (PS-SCA2). MATERIALS & METHODS: Heart rate variability (HRV) for 5-min series of RR intervals was analyzed in 48 PS-SCA2. Autonomic testing included resting recording, standing, Valsalva maneuver, and deep breathing. The results were compared with a group of sex- and age-matched controls. RESULTS: Time-and-frequency domain HRV indices were significantly different between PS-SCA2 and control groups. Using two standard diagnostic procedures were identified 4 (8.33%) subjects with severe and 8 (16.66%) subjects with early cardiac autonomic neuropathy in PS-SCA2. CAG index significantly correlated with age (-0.35) and HR (0.31). CONCLUSIONS: Our results confirm the presence of cardiovascular autonomic dysfunction in PS-SCA2 subjects.