Reacción a "A global study shows that physical, social and political factors influence ageing"

This is a very thorough, high-quality study on the combined effects of the exposome, i.e. exposure to different environmental factors throughout life, on the ageing process in more than 160,000 people in 40 countries. The authors start from a little-studied concept, that of biobehavioural age gaps (BBAGs), which they define as the difference between chronological age and estimated biological age.

They operationalise this using different individual indicators, such as cognitive functioning, functional capacity and well-being of the people included in the study. Using data extracted from large population surveys conducted in the participating countries, they analyse the risk and protective factors in the ageing process and how they influence the speed of ageing, while exploring differences between countries and between different socioeconomic variables. The authors have found that, among the components of the exposome studied, physical factors such as air quality, social factors such as gender equality, and political factors such as the existence of free and democratic elections influence the healthy ageing process and explain the differences between countries.

There is abundant evidence on the main factors that contribute to healthy ageing and the prevention of chronic diseases, although most studies focus on analysing some of them individually. The value of this study lies in the combination and harmonisation of different indicators to analyse the phenomenon of ageing from an integrated perspective that can help us design interventions aimed at eliminating modifiable risk factors. Traditional indicators such as chronological age or biological markers of ageing, which are often costly and invasive to measure, do not adequately reflect the complex process of ageing, as this study highlights.

Another point that I find noteworthy in the article is the comparison between countries, as it provides a macro view that helps us understand the importance of reducing socioeconomic inequalities in promoting healthy ageing.

[Regarding possible limitations] The concept of the biobehavioural age gap is recent and there is insufficient evidence or consensus on how to measure it. The choice of indicators used in the study is determined by their availability in the different population surveys used, which means that some relevant factors such as social support or access to healthcare are not included, which may limit the conclusions of the study. In addition, lower-income countries generally have poorer data sets from which to extract the required information, which could prevent or limit their participation in this type of study. However, these limitations do not detract from the relevance of the article. On the contrary, these results reinforce the importance of promoting research on the influence of the exposome on ageing and the need for further studies to explore this issue in greater depth.