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 s ystemic sclerosis (SSc) and mixed connective tissue disease (MCTD). Methods. Twenty-five patients with SSc (13 limited, 13 diffuse cutaneous di sease: disease duration 1-19 yrs) and 6 patients with MCTD (disease duratio n 1-10 yrs) were studied. Cardiovascular autonomic function was assessed us ing 5 standard tests and autoantibody status determined. Esophageal motor a ctivity and lower and upper esophageal sphincter pressures were recorded ma nometrically. Results. Five patients with SSc had definite, 7 borderline, and 13 no auton omic dysfunction; 23 had antinuclear, 9 anti-Scl70, 4 anticentromere, and 1 U1snRNP antibodies. Contraction amplitudes in the smooth muscle as well as the striated muscle esophagus and lower esophageal sphincter pressures wer e significantly lower and autonomic dysfunction more frequent in patients w ith than in those without anti-Scl70 (6 of 9 vs 6 of 16 patients); upper es ophageal sphincter pressures did not differ. All patients with MCTD had ant inuclear antibodies. 5 had definite autonomic dysfunction: their lower esop hageal sphincter pressures were significantly lower than in SSc patients wi thout anti-Scl70 and anti-U1snRNP. Conclusion. Esophageal motor dysfunction may be associated with the presenc e of anti-Scl70 and anti-U1snRNP autoantibodies and prevail in patients wit h cardiovascular autonomic neuropathy.