Life-Course Approach to Chronic Disease: The Active and Healthy Aging Perspective.

Abstract

To the Editor: Recently, there has been a dramatic increase in life expectancy in high-income countries, with a progressively aging population,1 that has been even more dramatic in the older ages, the population segment most exposed to the burden of multiple, simultaneously occurring, noncommunicable diseases (NCDs) (multimorbidity). The increase in life expectancy at age 80 in the last 30 years has been 8.7 years for men and 11.0 years for women. Unfortunately, a considerable portion of these years is still lived with disability; for each year of increase in life expectancy, the increase in healthy life expectancy was 0.75 years for men and 0.77 years for women aged 50 years old. The corresponding picture is a prevalence of disabilities of 30% in those aged 65–80% in those aged 85 and older.2 Chronic diseases and NCDs are a global health concern. Although most of them are preventable, 36 million people worldwide die from NCDs each year (63% of annual global deaths).3 Their treatment represents 70% of total healthcare costs: $6.3 trillion in 2010, projected to increase to $13 trillion by 2030. Progress in the prevention and management of NCDs—primarily in cardiovascular disease—and in therapeutic options has been the main contributor to the increase in life expectancy but also to the number of years lived with disability at older ages. For example, the significant decrease in fatality after a myocardial infarction has resulted in a progressive increase in the prevalence of heart failure. The life-course approach to NCD has become an increasingly popular concept.4, 5 Its core meaning is that opportunities to prevent NCD occur at different stages of life, targeting specific groups of subjects and with specific objectives at each stage. Basic prevention targets children in school to educate them about healthy eating and regular physical activity. The objectives of primary and secondary prevention—renamed milestones and put on the time scale of individual lifespan—are prevention of the rise in risk factors level and of NCDs. No focused attention has been placed on the prevention of disability after the clinical onset of NCD or on the identification of factors (biological and social risk or protective factors) that may affect the pace of the transition from a chronic condition to frailty and then disability.6 In the dominant paradigm, the life-course clock ends in middle age. This makes the current use of the life-course approach semantic, a trendy rewording of the traditional approach to NCD with no consideration of the challenges brought by an aging population.Active and healthy aging (AHA) refers to developing and maintaining the functional ability to maintain well-being into older age. The authors believe that the adoption of an AHA perspective on the life-course approach to NCD will require an understanding of the normal trajectory of physiological functions and the natural history of disease to old age. Research is needed to investigate and identify factors contributing to AHA at different stages of life, not only at younger ages and how exposure (or lack of exposure to protective factors) may differentially act at different stages of life, affecting functional reserve and rate of change of physiological factors with age (aging). Thus, the life-course approach should be based in a broader view than the dominant paradigm of simple “accumulation of risk” or the restriction of “critical time exposure” to early or intrauterine life.7 Arterial stiffness in the context of life-course approach to cardiovascular disease can be used as an example. Arterial stiffness can be quickly and noninvasively estimated in clinical practice in a highly reproducible manner as carotid–femoral pulse wave velocity. It is a continuum, consistently increasing with advancing age starting at age 20, largely independent of traditional cardiovascular risk factors (e.g., blood pressure, diabetes mellitus) and major independent predictors of cardiovascular disease.8 It is also a predictor of progression to cognitive impairment, a prevalent disabling condition “escaping” the interest of the traditional life-course approach to cardiovascular disease.9 Again, this is an example of the methodology the authors believe should replace current paradigms, not a unique example with accumulated evidence. The goal of a comprehensive and effective life-course approach to NCD is to identify and intensively follow subjects of any age with a greater than average rate of aging. This novel life-course approach to NCD offers a tremendous opportunity for effective prevention of events, preservation of functional reserve with advancing age, slowing disease progression, mitigating complications to optimize quality of life, and a decrease in demands on the healthcare system.10 In other words, the AHA perspective on the life-course approach to NCD considers heterogeneity in aging as an opportunity for personalized disease prevention and, consequently, to maximize the number of people who experience these positive trajectories of aging. Conflict of Interest: The authors declare no competing interests. Author Contributions: All authors contributed to this paper. Sponsor's Role: None.