Muscle sympathetic nerve activity in frontotemporal lobar degeneration is similar to amyotrophic lateral sclerosis

To determine whether frontotemporal lobar degeneration (FTLD) is associated with similar cardiovascular autonomic dysfunction to that seen in amyotrophic lateral sclerosis (ALS), we compared cardiovascular parameters between ALS patients and patients with FTLD. In ten patients with FTLD (mean age +/- A SD: 71.6 +/- A 4.6 years) and 12 patients with ALS (mean age +/- A SD: 71.4 +/- A 4.6 years), MSNA (using microneurography), heart rate (HR), and blood pressure (BP) were recorded simultaneously. MSNA was significantly higher in both groups of patients compared with the controls (p < 0.01), while there were no significant differences in MSNA between the patients with FTLD and those with ALS. During head-up tilt, changes in HR, BP, and the frequency of MSNA bursts were smaller in the patients than in controls (p < 0.05 or p < 0.01). Patients with FTLD and ALS showed similar dysfunction of HR, BP, and sympathetic outflow to muscles.