Research News

Cleveland Clinic researchers have developed a metabolic age clock that compares an individual's metabolic function to what’s typical for their age range. Using their clock, the researchers linked chronic obstructive pulmonary disease (COPD) with advanced metabolic age, supporting targeted anti-aging therapies for COPD. These findings are the first to link metabolic age to COPD.

Published in Metabolites by pulmonologist Russell Bowler, MD, PhD, the study advances our understanding of our biological age (how well certain organs or systems function) versus how long we’ve been alive in years (chronological age), and the role both features play in COPD.

“If you consider an individual’s unique background and features, you can tailor the parameters you look at when diagnosing and treating their conditions,” says Dr. Bowler, who is also Chair of Genomic Medicine. “We all know about how you can do this with a DNA test but our understanding of other factors like metabolic age are lagging behind.”

What is metabolic aging?

Someone with an advanced metabolic age has a slower metabolism than what’s typical for their chronological age. Metabolism is commonly used to refer to how efficiently we burn calories, but our metabolism controls far more than the process of burning energy. Cells use metabolic pathways to grow and divide, build and break down molecules and respond to stress.

Dr. Bowler hypothesized that an early decline in these pathways may contribute to a young person’s likelihood of developing “diseases of advanced age” like COPD.

"We lose about 50% of our lung function by the time we turn 75. Our metabolisms also slow down significantly,” he said. “If both metabolic and lung functions slow with age, it may be possible that an early decline in one could cause to early decline in the other.”

Dr. Bowler and his team aimed to use blood test results to quantify an individual’s metabolic age down to the decade – a metabolic clock. There was no accepted way to measure someone’s metabolic age beyond seeing how well they burn calories prior to this project, Dr. Bowler explains.

Dr. Bowler and his team analyzed lab results from almost 6,000 individuals aged 40-80 to identify metabolites where levels changed with age. Metabolites associated with inflammation, stress response and nutrition absorption showed changes as we age. Based on this data, the team determined a normal range of test values for each metabolic pathway for each decade of an individual’s life.

Establishing COPD as a disease of metabolic aging

Using their newly developed tool, Dr. Bowler’s team quickly found many metabolites associated with accelerated metabolic age in otherwise healthy individuals were also seen in individuals with COPD. The team also saw individuals with COPD and accelerated metabolic age had more severe symptoms and outcomes.

“Our findings suggest that diseases like COPD may be driven by the same pathologic processes observed in aging including energy production, amino acid deficiencies, stress responses, and more,” Dr. Bowler said. “They may help us understand why certain lung diseases like COPD are so strikingly associated with age and why lung function declines with age even in healthy individuals."

Dr. Bowler and his team are performing lab experiments to understand exactly how changes in cellular metabolism impact lung health and function. They are also working to develop age clocks for other biological processes including DNA methylation and protein expression.