title: Hyperglycemia in diabetics and non-diabetics: effect on the risk for and severity of pneumococcal pneumonia.
abstract: OBJECTIVE
  We sought to determine whether poor glucose control among diabetics is associated with increased risk for pneumococcal pneumonia and whether elevated admitting plasma glucose (APG) levels are associated with increased severity of this infection in diabetic and non-diabetic patients.
  
  
  METHODS
  We compared hemoglobin A(1c) (HbA(1c)) in diabetics who had pneumococcal pneumonia with diabetic case-controls who did not have pneumonia. In patients with pneumococcal pneumonia, we related APG to disease severity as determined by SMART-COP score, need for ICU admission, and mortality at 7 and 30 days.
  
  
  RESULTS
  Fifty-three of 233 patients with pneumococcal pneumonia (22.7%) were diabetic. Diabetics with pneumonia had poorer glycemic control than diabetic case-controls (HbA(1c) 8.2% vs. 7.2%, respectively, P<0.01). In pneumococcal pneumonia patients, SMART-COP scores, need for ICU admission, and mortality increased in proportion to the APG. These findings were attributable to the significant association between hyperglycemia and severity in non-diabetics.
  
  
  CONCLUSIONS
  Poor glycemic control predisposes diabetics to pneumococcal pneumonia but, among diabetics, the degree of hyperglycemia at admission is not associated with increased disease severity. In contrast, among non-diabetics with pneumococcal pneumonia, hyperglycemia is a marker for severe disease and increased mortality, perhaps reflecting massive release of cytokines and glucocorticosteroids in overwhelming infection.
authors.affiliation: Medical Service (Infectious Disease Section), Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX 77030, USA. adrianam.rueda@med.va.gov
authors.forename: Adriana M
authors.initials: AM
authors.lastname: Rueda
authors.forename: Mandy
authors.initials: M
authors.lastname: Ormond
authors.forename: Meghana
authors.initials: M
authors.lastname: Gore
authors.forename: Mahsa
authors.initials: M
authors.lastname: Matloobi
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Giordano
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Musher
mesh_terms: D000368:Aged; D048909:Diabetes Complications; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000150:complications*; D008297:Male; D008875:Middle Aged; D011018:Pneumonia, Pneumococcal / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology*; D012307:Risk Factors; D012720:Severity of Illness Index