High Blood Pressure, Other Risk Factors and Longevity: The. Insurance Viewpoint

Abstract The 1960–1962 National Health Survey indicates that about 15 per cent of the population suffers from definite hypertension (systolic pressure 160 mm Hg or higher, or diastolic pressure 95 mm Hg or higher) and that a like proportion has borderline hypertension (systolic pressure 140 to 159 mm Hg or diastolic pressure 90 to 94 mm Hg). The frequency of hypertension rises with advancing age and is greater for men than for women up to about age 50 years, but at the older ages the reverse is true. Follow-up studies of insured persons carried out over nearly 50 years have established that untreated blood pressures in excess of 140/90 mm Hg are associated with significant extra mortality over a period of years; for instance, in men under 40 with casual pressures of 150/100 mm Hg mortality was approximately 325 per cent that of standard insured risks, whereas corresponding men aged 40 and over showed a mortality of about 225 per cent. Such excess mortality increases with rise in blood pressure and is greater in the presence of other impairments or complications. On the other hand, the blood pressures optimal for longevity are those below 110 mm Hg systolic and 70 mm Hg diastolic. At ages under 55, cholesterol levels of 260 mg and higher are somewhat more common than systolic pressures of 150 mm Hg and higher (or diastolic pressures of 90 mm Hg and higher), but the reverse is true for men at ages 55 to 64 years. The Framingham and other studies show that hypertension is by and large the most important risk factor in coronary heart disease. Elevated serum cholesterol levels as a risk factor in coronary heart disease is strong at the younger ages only. Insofar as death rates from all causes are concerned, systolic pressures in excess of 150 mm Hg have a distinctly more adverse effect on mortality than does serum cholesterol of 265 mg and higher, especially at ages 45 to 64 years. This is because hypertension affects not only death rates from coronary heart disease but also those from hypertensive heart disease, cerebral vascular disease and renal complications, whereas the major effect of elevated serum cholesterol is on mortality from coronary heart disease. Inasmuch as blood pressure levels among people with slight or moderate hypertension remain relatively stable for considerable periods of time in a high proportion of cases, one of the major challenges to the clinician is to identify those hypertensive subjects in whom the underlying pathologic process is most acutely progressive.