Adiponectin Trajectories Before Type 2 Diabetes Diagnosis Whitehall II Study

OBJECTIVEdThe role of adiponectin in the natural history of diabetes is not well character-ized. We set out to characterize prediagnosis trajectories of adiponectin in individuals who develop type 2 diabetes. RESEARCH DESIGN ANDMETHODSdIn a case-cohort study (335 incident diabetes case and 2,474 noncase subjects) nested in the Whitehall II study, serum adiponectin was measured up to three times per participant (1991–1993, 1997–1999, and 2003–2004). Multilevel models adjusted for age and ethnicity were fitted to assess 13-year trajectories of log-transformed adiponectin preceding diabetes diagnosis or a randomly selected time point during follow-up (year0) based on 755/5,095 (case/noncase) person-examinations. RESULTSdAdiponectin levels were lower in diabetes case than in noncase subjects (median 7,141 [interquartile range 5,187–10,304] vs. 8,818 [6,535–12,369] ng/mL at baseline, P, 0.0001). Control subjects showed a modest decline in adiponectin throughout follow-up (0.3%per year,P,0.0001) at higher levels inwomen than inmen (difference at year0: 5,358 ng/mL, P, 0.0001). Female case and early-onset case (age at diagnosis,52 years) subjects had a steeper decline than control subjects (slope difference21.1 % per year, P = 0.001 in females,21.6 % pe