High blood pressure is very common

Worldwide, 26.4% of the adult population in 2000 suffered from hypertension (according to the following definition: average blood pressure ≥140/90 mmHg or use of antihypertensive medication, Kearney et al., 2005). In absolute numbers, 972 million adults had hypertension. These figures are predicted to increase by about 60% to 1.56 billion in the year 2025 (Kearney et al., 2005). As shown in Frequency of hypertension in people aged 20 years and older, the frequency of hypertension varies in different regions of the world and is lowest in parts of Asia and highest in established market economies, former socialist economies, and Latin America and the Caribbean. In established market economies such as Western European countries, North America and Japan, the prevalence of hypertension ranges between 20–50%.

Lack of routine monitoring and methodological differences restrict comparability of data

Comparable, representative and recent data on blood pressure and on the prevalence of hypertension for all EU member states are not available at present. Data on blood pressure are usually not collected in routine monitoring of health indicators, but rather in specific surveys which are often regional. Methodological differences in blood pressure measurement and data collection between countries also restrict the validity of comparing blood pressure data from surveys.

MONICA project shows substantial differences in the prevalence of hypertension between European countries

The most comparable data on blood pressure in different European countries are available from the WHO MONICA project. The project included representative, population-based samples from predefined regions. Blood pressure and other risk factors were assessed in a highly standardized way. The most recent data on blood pressure in the WHO MONICA project originate from the mid-1990s. As shown in Average systolic blood pressure among men and Average systolic blood pressure among women, the mean systolic blood pressure for the age group 35-64 varies considerably across countries and is generally lower in women than in men (WHO MONICA, 2003).

When a threshold of 140/90 mmHg is applied, prevalence of elevated blood pressure ranges from 19% to 60% among men and from 20% to 54% in women (Antikainen et al., 2006). Generally, blood pressure appears to be higher in North-Eastern European countries than in South-Western European countries.

Prevalence of hypertension in European countries is substantially higher than in North America

Whereas MONICA data use regional surveys, data presented in Prevalence of hypertension originate from population-based national surveys in England, Finland, Germany, Italy, Spain, Sweden, Canada and the United States that were conducted in 1988–1999 (Wolf-Maier et al., 2003). Participants in all but one of the surveys were aged 35-74 years (Spain: 35-65). The prevalence of hypertension in the European countries among men, based on the standard cut-off point of 140/ 90 mmHg or use of antihypertensive treatment, ranged from 45% in Italy and Sweden to 60% in Germany. Among women, the prevalence ranged from 31% in Italy to 50% in Germany. The respective data for North America (Canada and United States combined) indicate a much lower prevalence of hypertension in both men (30%) and women (25%). For a more detailed overview see Prevalence of hypertension. Across the whole age range, the Mean systolic and diastolic blood pressure is higher in the combined European countries than in North America.

The validity of the above comparisons between European countries is, however, limited, due to the differences in blood pressure measurement methods, age ranges, survey dates, participation rates and sampling methods (Wolf-Maier et al., 2003).

Blood pressure has declined in most developed countries over the last decades

As shown in the Spot maps of population changes in average systolic blood pressure, mean blood pressure decreased significantly between the mid-1980s and the mid-1990s in most of the 38 MONICA populations (WHO MONICA, 2003).

Individual populations differed considerably, but overall mean SBP (DBP) fell by 2.2 (1.4) mmHg in men and 3.3 (2.2) mmHg in women (Tunstall-Pedoe et al., 2006). Average declines were similar across the whole range of blood pressure readings and no differential fall in high readings attributable to more effective medication treatment was observed. Using the 160/95 mmHg and the 140/90 mmHg cut-off points, hypertension prevalence decreased in most of the MONICA populations (Antikainen et al., 2006).

Similarly, hypertension prevalence decreased in the United States until the beginning of the 1990s, but this trend was more recently reversed and the last available data from the NHANES 1999-2002 suggest increasing hypertension prevalence (Hajjar & Kotchen, 2003, Hajjar et al., 2006). There are no reliable recent trend summaries from Europe.

Awareness, treatment and control of hypertension in the population

Community surveillance that has been carried out in the field of hypertension offers the opportunity to evaluate the awareness, treatment, and control of high BP. Awareness is defined as reporting a diagnosis of high blood pressure. Treatment is defined as the use of antihypertensive medication. Control is defined as a blood pressure below a certain threshold, most commonly below 140/ 90 mm Hg. In national surveys from European countries (see above), awareness among those with BP ≥140/ 90 mmHg ranges from 36% in England and Germany to 52% in Italy (Wolf-Maier et al., 2004).

As shown in Hypertension awareness, treatment and control, the proportion of the population with a BP ≥140/ 90 mmHg receiving antihypertensive treatment varies between 25% in England and 32% in Italy. Overall control of hypertension among those aware of high BP amounts to 5% in Spain and up to 10% in England. Among those receiving antihypertensive treatment, control rates range from 19% in Spain to 40% in the England (Wolf-Maier et al., 2004). Compared to European countries, awareness, treatment, and control of hypertension appear to be substantially higher in the USA and Canada. In all countries, women have higher awareness, treatment and control rates than men. These data originate from 1986-1999 and blood pressure control may have increased since that time. The MONICA study shows that awareness, treatment and control of hypertension increased in the majority of study centres from the mid-1980s to the mid-1990s (Antikainen et al., 2006). More recent population-based investigations from Greece (Psaltopoulou et al., 2004), the Netherlands (Scheltens et al., 2007), and Portugal (Macedo et al., 2005) show awareness, treatment and control rates in the same order of magnitude.

Higher prevalence of high blood pressure among lower socio-economic groups

Analyses from eight nationally representative health surveys in Europe show that elevated blood pressure occurs more frequently in lower educated groups (as an indicator of socio-economic position) than in the higher educated population (Dalstra et al., 2005). This socio-economic difference in the prevalence of elevated blood pressure decreases in later life and is greater among women than among men. Also see EUphocus Health Inequalities.