Cold pressor test as a predictor of the severity of hypertension.

This report examines the cold pressor test (CPT) as it relates to the severity of hypertension. A total of 123 hypertensive patients were studied by physical examination, retinal funduscopy, chest roentgenogram, electrocardiogram, blood urea nitrogen measurement, and urinalysis. Causal and valid basal resting blood pressure determinations were made, followed by immersion of one hand in ice water for 2 minutes. All 21 patients with arteriosclerotic, 78 with essential, and 24 with renal hypertension had hyperreactive responses to the CPT (> 20/20 mm Hg) as compared with the normotensive subjects. The CPT-induced increase in diastolic pressure was significantly higher in hypertensives with left ventricular hypertrophy (LVH). CPT responses were also greater in hypertensives with higher degrees of retinopathy. These findings indicate that the diastolic rise on cold pressor testing can be used as a measure of severity of hypertension, especially in the presence of LVH and severe retinopathy. The CPT is inexpensive and noninvasive and can aid the clinician in managing the hypertensive patient. The CPT may also be useful as a predictor of complications of hypertension in selected individuals.