The challenge posed by the phenomenon of growing ageing populations is a real priority for many countries around the world. Not only in fully developed countries, but also in those with middle and low income economies, where the speed at which the ageing phenomenon is occurring exceeds all forecasts.
This is not new news; we have been hearing about the inversion of the population pyramid in the media for many years. In fact, the ageing of the population began in the 18th century with the structural and cultural reforms that conditioned a greater equity in the distribution of wealth and a greater secularisation of thought. Initially, there was an increase in the size of the population and later a stabilisation and modification of its structure by age and sex.
The birth rate, mortality and migratory movements (demographic transition) condition the size and structure, while changes in disease patterns (epidemiological transition) lead to greater longevity of the population. Infections, communicable and acute, are replaced by non-communicable and chronic diseases.
In this scenario, the World Health Organisation (WHO), in its “World report on ageing and health“, introduced new concepts not only from the biomedical field, but also from a sociological, moral, political and economic perspective, of great interest to those responsible for the care of the elderly.
These include Intrinsic Capacity, understood as the set of physical and mental capacities of an individual, which is marked by a series of conditioning factors ranging from genetic inheritance to the health characteristics of the individual (healthy behaviours and habits, physiological changes of ageing, risk factors, illnesses and injuries, etc.) and certain personal characteristics ranging from sex and race to those reflecting social norms, including work activity or the role of women in different cultures.
This intrinsic capacity endows the subject with functional abilities that should allow him or her to face the challenges that the environment generates. When this is not possible, disability appears which, consequently, is nothing more than the end result of a dialectic relationship between the subject and the environment.
The greater the distance between our intrinsic capacity and the challenges of the environment, the greater will be our functional reserve to face the growing challenges of that environment and, consequently, the greater will be our resilience, a term that has recently become very fashionable but which, as can be seen, is nothing more than the terminological modernisation of the old functional reserve.