1. The presence of autoantibodies and the histocompatibility leucocyte antigen (HLA) antigen B15 was studied in relation to vascular complications (WHO III) in 148 patients with essential hypertension.
2. Nine of 36 patients with WHO stage III hypertension had autoantibodies, compared with seven out of 78 normotensive controls.
3. The frequency of B15 was 36·1% in hypertensive patients with stage III hypertension and 14·8% in controls. Nine of 18 patients with cerebral complications had B15 and four out of 18 with cardiac complications had B15.
4. The relative risk of vascular complications was 3·4 times higher in B15-positive patients with essential hypertension compared with B15-negative patients.
5. This study suggests that B15-positive patients with essential hypertension represent a subgroup with a higher risk of vascular complications. Long-term studies are needed to determine whether B15 might serve as predictor for vascular complications.
6. The study adds further support to suggestions of a genetic and possibly HLA-linked connection between essential hypertension, diabetes and autoimmunity.