A small set of common blood biomarkers predicts which older adults will develop specific combinations of chronic diseases – and how quickly, a new study from Karolinska Institutet published in Nature Medicine reports.

Living with several chronic diseases at once, what is known as multimorbidity, is common among older people and puts a considerable strain on both the individual and the healthcare services. A collaborative study led by researchers at the Aging Research Center of Karolinska Institutet has now identified a small number of blood biomarkers that can predict the risk of multimorbidity. The study included over 2,200 individuals from the general Stockholm population, Sweden, above the age of 60.

Reflect biological processes

The researchers analysed 54 biomarkers in the blood of the participants that reflect biological processes such as inflammation, vascular health, metabolism and neurodegeneration. They then examined the correlation between these markers and three measures of multimorbidity: total number of diseases, five common disease patterns, and how quickly the diseases accumulated over a period of 15 years.

“We found that certain blood biomarkers, especially those connected with metabolism, were strongly linked to both specific disease combinations and how quickly new diseases developed,” says the study’s first author Alice Margherita Ornago, doctoral student at the Aging Research Centre at Karolinska Institutet’s Department of Neurobiology, Care Sciences and Society.

Seven significant biomarkers

Seven biomarkers proved particularly significant. Five of them – GDF-15, HbA1c, Cystatin C, leptin and insulin – were consistently associated with all the multimorbidity measures considered in the study. Two others – gamma-glutamyl transferase and albumin – were specifically linked to the speed of disease progression over time. The results were corroborated in an independent cohort of 522 participants in the USA.

“Our study suggests that disturbances in metabolism, stress responses, and energy regulation are among the main drivers of multimorbidity in older people,” says the principal investigator Davide Liborio Vetrano, associate professor in the same department. “This opens up the possibility of using simple blood tests to identify high-risk individuals, enabling earlier intervention in the future.”

The researchers are now planning to track how these blood biomarkers change over time and study whether lifestyle changes or medication can affect the pathological process.

The study was conducted in collaboration with researchers at the Royal Institute of Technology and SciLifeLab in Sweden, the University of Brescia and the University of Milano-Bicocca in Italy, and the National Institute on Aging in the USA. It was financed by the Swedish Research Council, Karolinska Institutet’s strategic research areas in epidemiology and neuroscience and the National Institutes of Health (USA). There are no declared conflicts of interest.