title: Prevalence of undiagnosed non-insulin-dependent diabetes mellitus and impaired glucose tolerance in a cohort of older persons with hypertension.
abstract: OBJECTIVE
  To determine the prevalence of undiagnosed non-insulin-dependent diabetes mellitus (NIDDM) and impaired glucose tolerance (IGT) in a cohort of older persons with hypertension. To examine the usefulness of screening for NIDDM in this study population.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  University of Tennessee, Memphis and the General Clinical Research Center (GCRC).
  
  
  METHODS
  Ninety-five participants in the Trial of Nonpharmacologic Interventions in the Elderly (TONE) study who agreed to participate in an ancillary study.
  
  
  METHODS
  A standard oral glucose tolerance test (OGTT) with insulin and C-peptide levels was performed before the beginning of the TONE intervention.
  
  
  RESULTS
  In this cohort, 43 participants (45.3%) had normal glucose tolerance (NGT), 41 (43.2%) had IGT, and 11 (11.6%) had undiagnosed NIDDM. The positive predictive value for NIDDM of a fasting glucose > or = 115 mg/dL in our participants was 57%. Hyperinsulinemia occurred in only one participant, a subject in the IGT group.
  
  
  CONCLUSIONS
  Our data demonstrate that undiagnosed NIDDM is common in our cohort of older persons who are being treated for essential hypertension and that impaired glucose tolerance may be more common than in the general population of the same age. Further, our data show that the vast majority of this older, obese, hypertensive cohort did not have fasting hyperinsulinemia. We also infer that a fasting glucose alone has a low positive predictive value for screening of NIDDM in our older cohort. As the prevalence of NIDDM and impaired glucose tolerance in older hypertensive patients in the general population is unknown, we believe that further investigation is needed to characterize the relationship of hypertension, glycemic status, and hyperinsulinemia in the general population.
authors.affiliation: Department of Preventive Medicine, University of Tennessee, Memphis 38105, USA.
authors.forename: K C
authors.initials: KC
authors.lastname: Johnson
authors.forename: M J
authors.initials: MJ
authors.lastname: Graney
authors.forename: W B
authors.initials: WB
authors.lastname: Applegate
authors.forename: A E
authors.initials: AE
authors.lastname: Kitabchi
authors.forename: J W
authors.initials: JW
authors.lastname: Runyan
authors.forename: R I
authors.initials: RI
authors.lastname: Shorr
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000175:diagnosis*; D005260:Female; D018149:Glucose Intolerance; D005951:Glucose Tolerance Test; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D015995:Prevalence