Retrospective and Prospective Study Aimed At the Pharmacoeconomic Evaluation of the Cost/effectiveness Ratio of Physical Exercise on the Prognosis of Non-alcoholic Fatty Liver Disease (NAFLD)

Physical inactivity and poor dietary habits are associated with an increased risk of obesity and chronic disease (World Health Organization, 2019; Glanz and Bishop, 2010). Conversely, higher levels of total physical activity result in a reduced risk of cardiovascular disease, breast and colon cancer, and diabetes (Kyu et al., 2016). Similarly, consumption of the minimum recommended level (600 g per day) of fruit and vegetables is associated with a lower risk of cardiovascular disease and cancer (Ezzati et al., 2004). However, despite these recognized benefits, unhealthy diet and physical inactivity are still major contributors to poor health and rising health care costs. Worldwide, physical inactivity accounted for 13.4 million disability-adjusted life years (DALYs) in 2013 and cost $53.8 billion to health systems and an additional $13.7 billion in productivity due to deaths attributable to physical inactivity (Ding et al., 2016).

Pharmacoeconomics, or the economic evaluation of treatments aimed at maintaining the health of the population, is a set of evaluation models used to identify the value (convenience) and the overall economic impact of a possible treatment.

The results of economic evaluations help decision makers inform their choice. Their advantage is that the result is obtained by applying known and validated models, and everyone can know the basis of the decision (evidence-based decision making). The clinical-economic value and the overall financial impact must be compared with the willingness to pay the related costs.

Economic evaluations are a tool for defining the value of a medicine in terms of cost-opportunity, from the point of view of the patient, the NHS and society as a whole.

The definition of "value" is very broad, multidimensional and includes concepts from many disciplines, beyond economics. Specifically, economic evaluations that take into consideration new medicines, innovative or not, the value is given by the marginal utility that the patient, the NHS and/or society can obtain from its acquisition. In this regard, the measurement of years of life gained in full quality of life (QALY - quality-adjusted life years) is widely applied to medicines in various regulatory contexts, albeit with the awareness that it is not able to capture all the elements that contribute to value (Carletto, A et al.; Drummond, M. F)