title: Hypoglycemia after antimicrobial drug prescription for older patients using sulfonylureas.
abstract: OBJECTIVE
  Certain antimicrobial drugs interact with sulfonylureas to increase the risk of hypoglycemia.
  
  
  OBJECTIVE
  To determine the risk of hypoglycemia and associated costs in older patients prescribed glipizide or glyburide who fill a prescription for an antimicrobial drug.
  
  
  METHODS
  This was a retrospective cohort study of Texas Medicare claims from 2006 to 2009 for patients 66 years or older who were prescribed glipizide or glyburide and who also filled a prescription for 1 of the 16 antimicrobials most commonly prescribed for this population.
  
  
  METHODS
  We assessed hypoglycemia events and associated Medicare costs in patients prescribed 1 of 7 antimicrobial agents thought to interact with sulfonylureas, using noninteracting antimicrobials as a comparison. We used a repeated measure logistic regression, controlling for age, sex, ethnicity, Medicaid eligibility, comorbidity, prior emergency department visits for hypoglycemia, prior hospitalizations for any cause, nursing home residence, and indication for the antimicrobial. We estimated odds of hypoglycemia, number needed to harm, deaths during hospitalization for hypoglycemia, and Medicare costs for hypoglycemia treatment.
  
  
  METHODS
  Any hospitalization or emergency department visit owing to hypoglycemia within 14 days of antimicrobial exposure.
  
  
  RESULTS
  In multivariable analyses controlling for patient characteristics and indication for antimicrobial drug use, clarithromycin (odds ratio [OR], 3.96 [95% CI, 2.42-6.49]), levofloxacin (OR, 2.60 [95% CI, 2.18-3.10]), sulfamethoxazole-trimethoprim (OR, 2.56 [95% CI, 2.12-3.10]), metronidazole (OR, 2.11 [95% CI, 1.28-3.47]), and ciprofloxacin (OR, 1.62 [95% CI, 1.33-1.97]) were associated with higher rates of hypoglycemia compared with a panel of noninteracting antimicrobials. The number needed to harm ranged from 71 for clarithromycin to 334 for ciprofloxacin. Patient factors associated with hypoglycemia included older age, female sex, black or Hispanic race/ethnicity, higher comorbidity, and prior hypoglycemic episode. In 2009, 28.3% of patients prescribed a sulfonylurea filled a prescription for 1 of these 5 antimicrobials, which were associated with 13.2% of all hypoglycemia events in patients taking sulfonylureas. The treatment of subsequent hypoglycemia adds $30.54 in additional Medicare costs to each prescription of 1 of those 5 antimicrobials given to patients taking sulfonylureas.
  
  
  CONCLUSIONS
  Prescription of interacting antimicrobial drugs to patients on sulfonylureas is very common, and is associated with substantial morbidity and increased costs.
authors.affiliation: Sealy Center on Aging, University of Texas Medical Branch, Galveston2Department of Internal Medicine, University of Texas Medical Branch, Galveston3Department of Preventive Medicine, University of Texas Medical Branch, Galveston4Department of Community He.
authors.forename: Trisha M
authors.initials: TM
authors.lastname: Parekh
authors.affiliation: Sealy Center on Aging, University of Texas Medical Branch, Galveston2Department of Internal Medicine, University of Texas Medical Branch, Galveston3Department of Preventive Medicine, University of Texas Medical Branch, Galveston4Department of Community He.
authors.forename: Mukaila
authors.initials: M
authors.lastname: Raji
authors.affiliation: Sealy Center on Aging, University of Texas Medical Branch, Galveston2Department of Internal Medicine, University of Texas Medical Branch, Galveston3Department of Preventive Medicine, University of Texas Medical Branch, Galveston4Department of Community He.
authors.forename: Yu-Li
authors.initials: YL
authors.lastname: Lin
authors.affiliation: Sealy Center on Aging, University of Texas Medical Branch, Galveston2Department of Internal Medicine, University of Texas Medical Branch, Galveston3Department of Preventive Medicine, University of Texas Medical Branch, Galveston4Department of Community He.
authors.forename: Alai
authors.initials: A
authors.lastname: Tan
authors.affiliation: Sealy Center on Aging, University of Texas Medical Branch, Galveston2Department of Internal Medicine, University of Texas Medical Branch, Galveston3Department of Preventive Medicine, University of Texas Medical Branch, Galveston4Department of Community He.
authors.forename: Yong-Fang
authors.initials: YF
authors.lastname: Kuo
authors.affiliation: Sealy Center on Aging, University of Texas Medical Branch, Galveston2Department of Internal Medicine, University of Texas Medical Branch, Galveston3Department of Preventive Medicine, University of Texas Medical Branch, Galveston4Department of Community He.
authors.forename: James S
authors.initials: JS
authors.lastname: Goodwin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000009:adverse effects*; D002939:Ciprofloxacin / Q000009:adverse effects; D017291:Clarithromycin / Q000009:adverse effects; D004347:Drug Interactions; D011307:Drug Prescriptions; D005260:Female; D005913:Glipizide / Q000009:adverse effects; D005905:Glyburide / Q000009:adverse effects; D017048:Health Care Costs; D006801:Humans; D007003:Hypoglycemia / Q000139:chemically induced* / Q000191:economics* / Q000453:epidemiology; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D064704:Levofloxacin / Q000009:adverse effects; D016015:Logistic Models; D008297:Male; D006278:Medicare; D008795:Metronidazole / Q000009:adverse effects; D009017:Morbidity; D016017:Odds Ratio; D012189:Retrospective Studies; D012307:Risk Factors; D013453:Sulfonylurea Compounds / Q000008:administration & dosage / Q000009:adverse effects*; D013781:Texas; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000009:adverse effects; D014481:United States / Q000453:epidemiology
chemical_list: D000890:Anti-Infective Agents; D007004:Hypoglycemic Agents; D013453:Sulfonylurea Compounds; D008795:Metronidazole; D002939:Ciprofloxacin; D064704:Levofloxacin; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D017291:Clarithromycin; D005905:Glyburide; D005913:Glipizide