June 17, 2008 — The diagnosis of hypertension in patients aged over 50 years should focus exclusively on the systolic blood pressure, rather than using both systolic and diastolic as is current practice, according to three experts in the field .
In a Viewpoint, published online in the Lancet today to coincide with presentation at the International Society of Hypertension meeting in Berlin, Germany, Drs Bryan Williams (Leicester Royal Infirmary, UK), Lars Lindholm (Umeå University Hospital, Sweden) and Peter Sever (Imperial College London, UK), say: "We believe that systolic blood pressure should become the sole defining feature of hypertension and key treatment target for people over age 50 years.
"A renewed focus on systolic pressure will simplify the message for practitioners and for patients, will improve awareness and understanding of treatment objectives, and will ultimately lead to more effective treatment of high blood pressure. Such an initiative would have major public-health implications for the prevention of blood-pressure-related cardiovascular disease," they conclude.
They note that there has been confusion about the relative merits of targeting systolic vs diastolic blood pressure, which has led to poor recognition in the wider medical community of the importance of systolic pressure. "Distilling the risk imparted by high blood pressure into a single number will greatly assist in both the communication of an important public-health message to patients and policy makers and in the simplification of treatment targets and thresholds for the physician. The minds of drug innovators will also be focused to develop better ways to treat high systolic pressure. At the moment, high blood pressure in most affected people remains inadequately treated, and modern drug development remains focused on the wrong target," they comment.
They point out that while systolic pressure rises with age, diastolic pressure increases until around age 50 and falls thereafter. "The use of diastolic pressure for diagnosis and risk stratification in our aging populations has thus become illogical," Williams et al state.
They note that clinical trials and national surveys have consistently shown that systolic pressure is much more difficult to control than is diastolic pressure, with control rates for diastolic pressure approaching 100% but lagging at less than 50% for systolic pressure. "Thus, targeting diastolic pressure leaves most patients with uncontrolled systolic pressure. By contrast, if the focus of our treatment were on systolic pressure, there would hardly ever be a circumstance when diastolic pressure was not controlled," they observe.
The authors report that the risk of cardiovascular disease rises continuously as systolic pressure increases from 115 mm Hg, and most national and international guidelines advocate a target for systolic pressure treatment of below 140 mm Hg, and below 130 mm Hg for patients with diabetes and those at increased cardiovascular risk. Noting that while the targets for patients at increased cardiovascular risk have been established from clinical-trial evidence, there is a lack of evidence from prospective randomized clinical trials to define unequivocally the optimum target for systolic pressure in patients with uncomplicated high blood pressure, and such trials are much needed.
What About the Under-50s?
Williams et al acknowledge that among people under age 40 years, as many as 40% of patients with high blood pressure have isolated diastolic hypertension, and between ages 40 and 50 years, such disease accounts for a third of hypertension. So they recommend that in patients younger than 50 years a continued emphasis on both diastolic and systolic pressures remains appropriate. But they note that this much smaller group of patients should not dilute the key message regarding the overwhelming importance of systolic pressure for most patients with hypertension, adding: "Even for those younger than 50 years, although diastolic pressure should always be controlled, systolic pressure should always be the main target."
Williams B, Lindholm LH, and Sever P. Systolic pressure is all that matters. Lancet 2008; DOI:10.1016/S0140-6736(08)60804-1. Available at: https://www.thelancet.com.
Heartwire from Medscape © 2008 Medscape
Cite this: Sue Hughes. Hypertension: Just Focus on Systolic Pressure in Over-50sfrom Heartwire — a professional news service of WebMD - Medscape - Jun 17, 2008.