Frailty is common in elderly people with cardiovascular disease and goes along with elevated mortality. However, no consensus exists on the definition of frailty. Many scores have been developed to assess frailty and to make predictions on disease and mortality, but there is no gold standard. Dr Gloria Aguayo from the Luxembourg Institute of Health (LIH) and co-workers examined the predictive ability of 35 frailty scores for cardiovascular disease, cancer and all-cause mortality using data from the English Longitudinal Study of Ageing. The analysis, recently published in PLOS Medicine, reveals that all frailty scores are associated with future mortality, and that some are linked to cardiovascular disease but none to cancer. The study underscores that the comparative evaluation of strength of associations between health outcomes in elderly people provides a solid evidence base for researchers and health professionals.
In March 2018, the Open Access journal PLOS Medicine published a special issue on "Cardiovascular disease and multimorbidity". One of the featured research articles is that of Dr Gloria Aguayo, scientist at the Epidemiology and Public Health Research Unit in LIH's Department of Population Health, and her collaboration partners. In this study, the scientists analysed 35 frailty scores - identified by a systematic literature review - on their ability to predict mortality, cardiovascular disease and cancer. Data was used from 5,294 adults aged 60 years or more and followed up over a period of seven years within the English Longitudinal Study of Ageing.
The researchers observed that all frailty scores were associated with all-cause mortality, some were also associated with the incidence of cardiovascular disease, but none were associated with cancer events. In models adjusted for demographic and clinical information, 33 out of 35 frailty scores showed significant added predictive performance for all-cause mortality. Certain scores outperform others with regard to all-cause mortality and cardiovascular health outcomes in later life. The authors specify that multidimensional frailty scores may have a more stable association with mortality and incidence of cardiovascular disorders.
'This study addresses one of the most relevant issues in healthcare and research on aging populations: how to diagnose and assess frailty, given the availability of many different frailty scores and the lack of a gold standard', says Dr Aguayo. 'Our study provides a direct comparison of the most complete list of frailty scores examined to date, using an advanced and reproducible methodology, in a well-characterised cohort representing the general elderly population.'
The study highlights the vast heterogeneity in the composition and performance of existing frailty scores. Dr Aguayo believes that the findings of the study will help clinicians in choosing the most appropriate instrument to assess frailty and associated health outcomes for their purpose. Notably, this research work is the first to compare the performance of frailty scores with respect to cancer incidence.
The study is the result of a tight collaboration between the Epidemiology and Public Health Research Unit at LIH's Department of Population Health and researchers from LIH's Competence Centre for Methodology and Statistics, the University of Liège, the VU University Medical Centre in Amsterdam in the Netherlands, the University of Western Ontario in Canada and the Aarhus University in Denmark.