title: Long-range negative correlation of glucose dynamics in humans and its breakdown in diabetes mellitus.
abstract: Diurnal fluctuations in glucose levels continuously monitored during normal daily life are investigated using an extended random walk analysis, referred to as detrended fluctuation analysis (DFA), in 12 nondiabetic subjects and 15 diabetic patients. The DFA exponent alpha = 1.25 +/- 0.29 for healthy individuals in the "long-range" (>2 h) regime is shown to be significantly (P < 0.01) smaller than the reference "uncorrelated" value of alpha = 1.5, suggesting that the instantaneous net effects of the dynamical balance of glucose flux and reflux, causing temporal changes in glucose concentration, are long-range negatively correlated. By contrast, in diabetic patients, the DFA exponent alpha = 1.65 +/- 0.30 is significantly (P < 0.05) higher than that in nondiabetic subjects, evidencing a breakdown of the long-range negative correlation. It is suggested that the emergence of such positive long-range glucose correlations in diabetic patients-indicating that the net effects of the flux and reflux persist for many hours-likely reflects pathogenic mechanisms of diabetes, i.e., the lack of long-term stability of blood glucose and that the long-range negatively correlated glucose dynamics are functional in maintaining normal glucose homeostasis.
authors.affiliation: Graduate School of Education, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Ogata
authors.forename: Kumpei
authors.initials: K
authors.lastname: Tokuyama
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Nagasaka
authors.forename: Akihiko
authors.initials: A
authors.lastname: Ando
authors.forename: Ikuyo
authors.initials: I
authors.lastname: Kusaka
authors.forename: Naoko
authors.initials: N
authors.lastname: Sato
authors.forename: Akiko
authors.initials: A
authors.lastname: Goto
authors.forename: Shun
authors.initials: S
authors.lastname: Ishibashi
authors.forename: Ken
authors.initials: K
authors.lastname: Kiyono
authors.forename: Zbigniew R
authors.initials: ZR
authors.lastname: Struzik
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Yamamoto
mesh_terms: D000222:Adaptation, Physiological; D001786:Blood Glucose / Q000378:metabolism*; D002940:Circadian Rhythm; D003198:Computer Simulation; D003920:Diabetes Mellitus / Q000378:metabolism*; D005260:Female; D006706:Homeostasis; D006801:Humans; D007700:Kinetics; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D013223:Statistics as Topic; D013997:Time Factors
chemical_list: D001786:Blood Glucose