Creatinine height index in a sample of Japanese adults under sedentary activities

The value of creatinine height index (CHI), defined as milligrams of 24-h urinary excretion of creatinine divided by height in centimeters, was investigated on 21 healthy Japanese adults engaged in sedentary work. The average values were 10.58 in males and 6.68 in females. High partial correlation coefficients controlling sex were found among CHI, weight, fat-free mass, arm muscle area (AMA) and 24-h urinary excretion of creatinine. These indices had high loadings in the first factor of body size by principal component analysis. Regression of CHI on AMA differed in the intercept (i.e. the level of CHI at corresponding AMA) but not in the slope, from that studied under low-creatine diet in the U.S.A. Correcting AMA using arm bone area for Japanese and CHI with dietary factor, the relation between CHI and AMA in this study seemed to be in good agreement with that found in the U.S.A.