Standard lab tests mislabel normal aging in Chinese adults

In an observational preprint, researchers analysed laboratory data from 4,392 healthy adults (1,894 men and 2,498 women) aged 18 to 91 in Beijing across four survey waves between 2010 and 2026. Examining age-dependent biomarker trajectories, they identified four turning points around ages 35, 50, 60, and 70 years. The inflection between ages 50 and 55 in peri-menopausal women was the most consistent. Standard reference intervals applied uniformly across all ages deviated substantially from these patterns: 42 of 160 indicator-sex-age groups (26.3%) had out-of-range rates above 20%, including cholesterol in 58.8% of women aged 50 to 59 years. In cross-year validation, new age- and sex-specific reference intervals achieved closer-to-target out-of-range rates in 60.9% of groups.