In the medium term, technological changes play a more important role in explaining growth. In the long run, risk factors, such as obesity, and changes in the prevalence of chronic diseases also enter the picture (Thorpe et al., Factors influencing the future trajectory of health spending include demand-side factors, such as ageing and the health status of a population, income growth, and consumers' behaviour; supply-side drivers, such as technological progress and changes in treatment practices, productivity, and health prices2; and regulatory factors, such as institutional characteristics of health systems and their financing'.