Autoantibodies and vascular events in essential hypertension: a five-year longitudinal study.

The relationship between serum autoantibodies and vascular events was investigated in 140 patients with essential hypertension during a five-year period. The influence of time upon incidence of autoantibodies was assessed in 55 normotensive controls of roughly the same distribution of age and sex. Thirty-four patients experienced a vascular event, which was fatal in 10 cases (7.1%). Eight of these 10 patients had autoantibodies in serum before the events, and the presence of autoantibodies at entry to the study tripled the five-year relative risk for vascular events. Antinuclear antibodies (ANA) and smooth muscle antibodies (SMA) especially contributed to this increased risk. The vascular events were followed by a significantly increased occurrence of ANA. In the control subjects no events occurred and no significant increases in the presence of autoantibodies were found during the five years. ANA and SMA positive sera showed no significant complement fixing properties, and the autoantibodies studied seemed to be secondary to tissue damage. Despite this, they seemed to reflect an ongoing injury of the vascular bed.