Blood Pressure and Vascular Reactivity to the Cold Pressor Test

Of 300 subjects who had cold pressor tests in 1934, 207, aged 33 to 46 yr, were restudied in 1961. The test was repeated in 151 cases; in others, current information was supplied by subjects' physicians. Thirty-one subjects, hyperreactive in 1934 and retested, remained hyperreactive; 21 previously normal reactors became hyperreactive. Of 40 hyperreactors in 1934, four became hypertensive, whereas none of 167 normal reactors did so. In 1961, the family histories were positive for hypertension for 19 of 27 subjects hyperreactive in 1934 and for 30 of 43 hyperreactive in 1961; for normal reactors, corresponding figures were 37 of 112 and 26 of 96. These findings support the concepts that transient vasoconstriction precedes development of hypertension and that vascular hyperreactivity is inherited and may predispose to hypertension.