Sarcopenic obesity is the co-existence of obesity and sarcopenia in individuals aged 40-75 years. The Japanese Working Group on Sarcopenic Obesity has developed diagnostic criteria tailored for the Japanese population, considering their unique characteristics compared with European populations.

Our algorithm consists of two steps: screening and diagnosis. The screening of obesity mandates using waist circumference and/or body mass index (BMI) based on national standards, while screening for sarcopenia involves the "finger ring test" in addition to the Asian Working Group for Sarcopenia 2019 criteria.

The final diagnosis of sarcopenia involves handgrip strength for low muscle strength, the five-times chair stand test for low physical function, and limb skeletal muscle mass (corrected for BMI) for low muscle mass. Obesity is assessed by visceral fat area or body fat percentage.

Sarcopenic obesity is then categorized into Stage I, with muscle weakness/loss of function, loss of muscle mass, and obesity; or Stage II, which includes complications. Further clinical validation is needed to refine the consensus and age range.

Geriatr Gerontol Int 2024; ••: ••-••.