Figure 1.Differences in serum kynurenine and tryptophan levels and their ratio according to the phenotypic frailty status (A) before and (B) after adjusting for sex, age, and BMI. Phenotypic frailty is defined based on the Fried’s criteria. The estimated means with 95% confidence intervals were generated and compared using an analysis of covariance. Delta (Δ) indicates a change in the value of a variable between groups. Abbreviations: BMI, body mass index; Kyn, kynurenine; Tryp, tryptophan.
