[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.