Autonomic nerve function in patients with systemic scleroderma using heart rate variability analysis

We examined autonomic nerve function in patients with systemic scleroderma (SSc) using power spectral analysis of heart rate variability. In the SSc group, both in nighttime (0:00a.m.-5:00a.m.) and daytime (10:00a.m.-5:00p.m.), HF elements, a parasympathetic nerve index, were lower and LF/HF ratios, a sympathetic nerve index, were higher than in the control group. This suggests that in SSc patients, sympathetic nerve activity was increased and parasympathetic nerve activity was decreased throughout the day.