title: Low lung function and risk of type 2 diabetes in Japanese men: the Toranomon Hospital Health Management Center Study 9 (TOPICS 9).
abstract: OBJECTIVE
  To evaluate the effect of elevated fasting plasma glucose (FPG) and hemoglobin A(1c) (HbA(1c)) concentrations on lung dysfunction and to prospectively investigate whether reduced lung function would be independently predictive of diabetes.
  
  
  METHODS
  From January 6, 1997, through December 22, 2008, we observed 5346 men with no history of diabetes or lung dysfunction. Hazard ratios (HRs) for incident diabetes (FPG ≥126 mg/dL, HbA(1c) ≥6.5%, or self-reported clinician-diagnosed diabetes) were estimated for spirometry indices as continuous and categorical variables.
  
  
  RESULTS
  Elevated HbA(1c) concentrations within the normal range were significantly and more strongly associated with reduced forced vital capacity and forced expiratory volume in the first second after expiration (FEV(1)) than were FPG concentrations. During a 4.0-year follow-up, diabetes developed in 214 individuals. A 10-point decrease in percentage of FEV(1) predicted value was associated with an increased HR of 1.21 (95% confidence interval [CI], 1.09-1.34; P=.001) for diabetes after adjustment for demographic factors and body mass index. This association remained significant even after adjustment for metabolic factors, smoking status, and FPG or HbA(1c) concentrations but was attenuated substantially after adjustment for baseline HbA(1c) values (HR, 1.13; 95% CI, 1.01-1.26; P=.03). Lower quartile (Q) categories of percentage of FEV(1) predicted value were associated with increased risk of diabetes independently of known predictors including HbA(1c) (HR, 1.73; 95% CI, 1.14-2.62 for Q1; and HR, 1.76; 95% CI, 1.15-2.69 for Q2).
  
  
  CONCLUSIONS
  Reduced lung function was significantly related to chronic glycemic exposure within a normal range. Relatively low pulmonary function was an independent risk factor for diabetes in apparently healthy Japanese men.
authors.affiliation: Department of Internal Medicine, Niigata University Faculty of Medicine, Japan.
authors.forename: Yoriko
authors.initials: Y
authors.lastname: Heianza
authors.forename: Yasuji
authors.initials: Y
authors.lastname: Arase
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tsuji
authors.forename: Kazumi
authors.initials: K
authors.lastname: Saito
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Amakawa
authors.forename: Shiun Dong
authors.initials: SD
authors.lastname: Hsieh
authors.forename: Satoru
authors.initials: S
authors.lastname: Kodama
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Shimano
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Yamada
authors.forename: Shigeko
authors.initials: S
authors.lastname: Hara
authors.forename: Hirohito
authors.initials: H
authors.lastname: Sone
mesh_terms: D001786:Blood Glucose / Q000378:metabolism; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000453:epidemiology / Q000503:physiopathology*; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007564:Japan / Q000453:epidemiology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012129:Respiratory Function Tests; D012307:Risk Factors; D011795:Surveys and Questionnaires
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin