OBJECTIVES: The burden of chronic diseases is an important parameter for financial resource allocation and health care system capacity planning. Future prevalence and distribution of chronic conditions depend on the development of population size and structure. The European population is expected to slowly grow and rapidly age in the next decades. Our contribution aims at evaluating the impact of demographic change on prevalence of hypertension in Europe. The use of projections to support long-term planning of health care resources will be discussed. METHODS: A prevalence-projection scenario was developed combining age-/sex-specific population projections with chronic disease prevalence rates. Population projections were taken from Eurostat statistics. Hypertension prevalence rates were estimated from the European Healthcare Access Panel (EHP, 2008), a representative health and healthcare utilization survey in five EU countries (Germany, UK, France, Italy and Spain). The weighted sample comprised 136.397 respondents aged 20-79. Multiplying projected population numbers with the respective age- and sex-specific hypertension rates from 2008 provided an estimate for the number of hypertensives by country in forthcoming years. RESULTS: As calculated from EHP data, in 2010, 15.9M Germans aged 20 to 79 years suffered from hypertension (10.4M in UK, 8.2M in France, 9.7M in Italy and 6.4M in Spain). For the year 2025, our model predicts the prevalence figures to increase to 17.3M in Germany, 12.3M in UK, 9.6M in France, 11.3M in Italy and 7.8M in Spain. For all five countries combined hypertension is calculated to increase by 15.3%, from 50.6M to 58.4M. CONCLUSIONS: The projections show a considerable increase in the prevalence of hypertension: the total population in the five biggest EU countries will grow only by 5.7% but the number of people with hypertension will increase by 15.3%. These data quantify the influence of ageing on disease burden and reflect an increased need for appropriate health care expenditure and capacities.