In this issue of the Journal of Human Hypertension, Gasse and her colleagues report no progress in 10-year trends (1984/85 to 1994/95) in prevalence, detection, treatment, and control of hypertension in a German population studied with standardised methods of the collaborative WHO-MONICA Project.1 Prevalence of hypertension did not go down over the 10 years, and rates of detection, treatment, and control did not improve either. This report underscores the indispensability of such high-quality epidemiological surveys to evaluate effectiveness of hypertension control efforts in clinical and public health practice. Such surveys need to be organised as ongoing endeavours in every country. They have to be epidemiologically appropriate, ie, involving large enough samples from each age–sex stratum of general populations, and also of subpopulations of special concern (eg, lower socioeconomic strata, often with particularly adverse blood pressure (BP) distributions and prevalence rates of hypertension). High-quality standardised methods are essential, as are trained and certified staff. To establish trends over time, these surveys need to be repeated periodically—eg, at intervals of 5 to 10 years. Both main substantive findings of Gasse and colleagues—on lack of progress in Germany, (1) in reducing prevalence of high BP (HBP), and (2) in improving HBP detection, treatment, and control—merit thoughtful attention. In our judgment, the following are important challenges for future progress on these two fronts. Reducing prevalence of adverse BP levels throughout the populationThe data reported by Gasse et al1 show no decline in prevalence of hypertension and no change in average BP levels of this German population.1,2 Experiences in other industrialised countries indicate that progress can be made in this decisive area. Thus, as discussed by Gasse et al,1 their finding is in contrast with declines of hypertension prevalence in such countries as Belgium, Denmark, Finland, and the USA. For example, in the USA, age-adjusted prevalence of hypertension (systolic BP/diastolic BP 140/90 mm Hg) declined from 36.3% in 1971/74 to 20.4% in 1988/91; average values of SBP/DBP decreased from 131/83 mm Hg to 119/73 mm Hg, ie, a population-wide downward shift was achieved in the BP distribution (at least a portion of this decline was assessed to be real, and not artefactual).3 Available data from many populations show that frank HBP is the upper end of adverse BP levels prevailing for most people aged 35 and older, and leading to significant excess risk of sickness, disability, and death, particularly from cardiovascular diseases (CVD). Only a small minority have optimal SBP/DBP readings, ie,  120/80 mm Hg.4 Therefore, shifting the BP distribution downward for the whole population is the central strategic challenge. For this purpose, improving lifestyles, particularly improving eating and drinking patterns, is key—not pharmacologic therapy.5,6 In fact, drug treatment was estimated to account for no more than 5–6% of an approximately 10 mm Hg fall in population average DBP from 1972 to 1992 in Finland.7 This substantial BP reduction was assessed as resulting mainly from population adherence to advice to decrease salt intake and the ratio of Na to K in the diet. National recommendations and legislation in Finland include labelling salt content of commercially prepared foods and use of potassium-magnesium-enriched mineral salt instead of common salt in homes and the food industry. Improving nutrition can be accomplished by application of three complementary approaches: The first—a population strategy—involves the entire community, to prevent rise in BP with age and to achieve a downward shift in the entire BP distribution. This is 'primordial prevention' (the apt term from WHO)—primary prevention of this major risk factor from developing in the first place. It means progressive increase in proportion of the population with optimal SBP/DBP throughout life. It begins with conception and post-weaning, and continues throughout life. In fact, with population average SBP/DBP at ages 18–24 <120/<80 mm Hg for both men and women of many countries, epidemic adverse BP levels would cease with large-scale prevention of current common increases in SBP/DBP during adulthood. Even modest initial progress toward this goal is valuable. Thus, an US report estimated that a 2 mm Hg average reduction in population DBP results in a 17% decrease in prevalence of HBP.8 A second—complementary—arm of strategy involving better nutrition entails special attempts to lower BP through intense dietary counselling for those at greater risk of developing hypertension. This focuses on persons with BP in the high-normal range, with a family history of hypertension, the obese, those with especially unfavourable lifestyles. Estimates are that targeted intervention lowering adverse DBP (eg, high-normal—85–89 mm Hg) by as little as 1 to 3 mm Hg can reduce HBP incidence by 20% to 50%.9,10 A third component of strategy emphasising improved nutrition to lower BP has as its focus people who are already hypertensive. This is secondary, not primary, prevention of HBP, by non-pharmacologic means. With availability now of results from two DASH feeding trials,11,12,13 the possibility and practicality of this approach are greatly enhanced. Data from the most recent US National Health and Nutrition Survey (NHANES-III) indicate that lower prevalence of HBP in the US in 1988/91 can be accounted for in part by nutritional improvements made by people with a history of HBP who were non-hypertensive without antihypertensive drug at that survey.3,4 The impressive DASH data11,12,13—confirming that BP is influenced importantly by multiple dietary factors including salt—demonstrate directly and definitively the soundness of improving nutritional patterns for the primary and secondary prevention of HBP throughout the population. The DASH eating pattern that worked best, ie, the DASH combination diet and Na at 50 mmol/day, is the cornerstone of that strategy—along with calorie moderation to prevent and control obesity, and avoidance/correction of excess alcohol consumption. The DASH combination diet is high in fruits and vegetables, also in fat-free and low-fat dairy products, and reduced in total fat, saturated fats, cholesterol, and sweets.11 Compared to those randomised to usual American fare (including 150 mmol of Na/day), participants fed this combination diet with Na at about 50 mmol/day experienced average SBP/DBP reduction of 8.9/4.5 mmHg—7/4 mm Hg for non-hypertensives, 11.5/6 mm Hg for hypertensives.12,13 The combination fare and salt reduction contributed synergistically to the consistent BP fall. Na at 50 mmol/day had a greater BP lowering effect than at 100 mmol/day. This DASH eating pattern has two additional merits: (1) its dietary fat and fibre composition are, along with control of weight and alcohol intake, favourable also for prevention and correction of dyslipidaemia (an established major risk factor), and (2) its level of dietary total fat—<25% of kilocalories—enables consumption of hearty fare, replete with essential nutrients, but moderate in calories, ie, it can facilitate prevention and correction of obesity (along with regular frequent moderate exercise). Thus, the scientific data are now in hand making possible the progressive reduction in prevalence throughout the population of both major diet- dependent cardiovascular risk factors, adverse levels of blood pressure and of serum lipids. The challenge is the progressive application of this knowledge population-wide. Improving detection, treatment, and control of high BP throughout the populationLike many other countries, Germany has a National High Blood Pressure Programme (established in 1985) aiming to improve detection, treatment, and control of hypertension. This programme was reported to include worksite screening for hypertension, BP measurement training for nurses, and a telephone service for the public.14 The first two of these are for earlier detection; 80% of callers to the telephone service were reported to be patients with hypertension. Lacking detailed knowledge and experience with the German situation, we would be presumptuous to evaluate it and to offer specific suggestions for its improvement. That task is for our German colleagues in medical care and public health. However, we can note that—to the best of our knowledge—in every country the level of HBP control for hypertensive people is less than 50%, based on a goal of SBP/DBP <140/<90 mm Hg (still considerably above optimal SBP/DBP). Therefore, with such programmes in place since the 1970s and 1980s, every country faces a challenge—including those countries where much has been accomplished by implementation of a high-risk strategy. In the USA, the National High Blood Pressure Education Program—aware of this challenge and responding to it—recommends a renewed and extended national campaign.15 Obviously, for this decade at the very least, and probably for longer, there will continue to be tens of millions of people with frank hypertension worldwide—even with sizable advances in improving lifestyles and thereby preventing HBP. More effective approaches for the earliest detection, evaluation, treatment, and sustained control of epidemic HBP must therefore be a high-priority concern for medical care and public health in every country. These approaches must above all encompass enhanced therapeutic methods that utilise in optimum ways both the powerful nutritional-hygienic and pharmacologic tools available for sustained control of HBP. Perspective In noting this need to deal more effectively with implementation of high-risk strategy focussed on people with hypertension, we must at the same time emphasise the serious limitations of an exclusive focus on high-risk strategy, involving only detection, evaluation, and treatment (usually including drug therapy) of people with already established high BP. It is late, defensive, reactive (not proactive), associated with adverse effects (inevitable with drugs), costly, only partially successful (it rarely reduces HBP to optimal levels), and endless. It offers no possibility of ending the high BP epidemic. Also, it has no impact—and cannot have any impact—on the excess risks of BP-related CVD in non- hypertensive persons with BP above optimal. In fact, about 40% of all BP-related CVD occurs in non-hypertensive individuals with BP above optimal.16 Furthermore, for young adults with HBP, drug treatment is problematic; there are no clinical trial data, no trials ongoing, and—to the best of our knowledge—none planned involving young adults with HBP. Yet, as our 25-year follow-up data on men aged 18–39 make clear, BP above normal is significantly related to increased long-term CVD mortality and shortened life expectancy for this age group also. The large strata with high-normal BP and Stage 1 HBP accounted for 60% of all excess deaths from CVD and all-causes.17 To solve the problem of population-wide adverse BP levels, including frank HBP, high-risk strategy is not enough. Major emphasis must be given to primordial prevention by improving lifestyles—the top priority. The primary prevention of this major risk factor in the first place, throughout the population, is a strategy whose time has come.
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