SUMMARY To determine the usefulness of the cold pressor test as a predictor of hypertension, we compared the blood pressure recordings available from 142 patients in 1979 with readings obtained during performance of two cold pressor tests, the first in 1934 when these subjects were children, and the second in 1961. Forty-eight subjects were hyperreactors to the tests in either 1934 or 1961, and 94 were normoreactors. At last follow-up, blood pressures in 14 of the hyperreactors were between 140 and 160 mm Hg systolic or 90 and 100 mm Hg diastolic (Stratum 1) and in 20 exceeded 160 mm Hg systolic or 100 mm Hg diastolic (Stratum 2). Ten normoreactors had casual blood pressures in Stratum 1 and eight in Stratum 2. Hypertension had thus occurred in 71% of the hyperreactors and 19% of the normoreactors. Fifteen hyperreactors were receiving antihypertensive therapy, and this reduced the severity of the casual blood pressure elevation in most patients to Stratum 1. Antihypertensive therapy had been started in three normoreactors. The duration of follow-up, 45 years, and the mean age at follow-up, almost 57 years, were greater in this study than in any previously reported study. Early hyperreactivity was related to future hypertension in enough subjects to suggest that an abnormal response to an external cold stimulus may be useful as an indicator of future hypertension. (Hypertension 6: 301-306, 1984) KEY WORDS • cold stimulus • blood pressure • hyperreactivity A LMOST 50 years ago, Hines and Brown 1 proposed that a period of vascular hyperreactivity preceded the development of sustained hypertension. They further suggested that vascular hyperreactivity manifested by an excessive pressor response to an external cold stimulus was a potential predictor of hypertension. Subsequent investigators have used the cold pressor test but have disagreed about its usefulness as a predictor of hypertension.2 "
1We report here the results of a 45-year follow-up study of 142 subjects who were originally studied by Hines, in an attempt to determine the value of the cold pressor test as an indicator of future hypertension.
MethodsIn 1934, 300 Rochester, Minnesota, schoolchildren aged 7 to 17 years were studied by means of the cold pressor test. In 1961, 151 of the original subjects were again studied with use of a cold pressor test. 5 The Mayo Clinic records of the 151 subjects who had been given cold pressor tests in 1934 and 1961 were reviewed in 1979 without knowledge of the test responses. Casual blood pressure recordings made during routine office visits were abstracted from each patient's record. In most instances, more than two blood pressure readings were available for each patient during the last year of follow-up. In this circumstance an average blood pressure was determined.For the purposes of this study, a blood pressure level of less than 140/90 mm Hg is described as normotension. Higher pressures indicating hypertension were graded in the following manner: blood pressures of 140 to 159 mm Hg systolic or 90 to 99 mm Hg d...