Cardiovascular autonomic function, autoantibodies, and esophageal motor activity in patients with systemic sclerosis and mixed connective tissue disease.

OBJECTIVE: To study cardiovascular autonomic nerve function and presence of autoantibodies in relation to esophageal motor activity in patients with systemic sclerosis (SSc) and mixed connective tissue disease (MCTD).
METHODS: Twenty-five patients with SSc (13 limited, 12 diffuse cutaneous disease; disease duration 1-19 yrs) and 6 patients with MCTD (disease duration 1-10 yrs) were studied. Cardiovascular autonomic function was assessed using 5 standard tests and autoantibody status determined. Esophageal motor activity and lower and upper esophageal sphincter pressures were recorded manometrically.
RESULTS: Five patients with SSc had definite, 7 borderline, and 13 no autonomic dysfunction; 23 had antinuclear. 9 anti-Sc170, 4 anticentromere, and 1 U1snRNP antibodies. Contraction amplitudes in the smooth muscle as well as the striated muscle esophagus and lower esophageal sphincter pressures were significantly lower and autonomic dysfunction more frequent in patients with than in those without anti-Sc170 (6 of 9 vs 6 of 16 patients); upper esophageal sphincter pressures did not differ. All patients with MCTD had antinuclear antibodies, 5 had definite autonomic dysfunction; their lower esophageal sphincter pressures were significantly lower than in SSc patients without anti-Sc170 and anti-U1snRNP.
CONCLUSION: Esophageal motor dysfunction may be associated with the presence of anti-Sc170 and anti-U1snRNP autoantibodies and prevail in patients with cardiovascular autonomic neuropathy.