title: Factors associated with time to follow-up of severe hyperkalemia in the ambulatory setting.
abstract: BACKGROUND
  Few studies have investigated the time it takes physicians to follow up abnormal outpatient laboratory results.
  
  
  METHODS
  Medical record review of all adult patients seen at a primary care practice between January 2002 and December 2005 with serum potassium results > or = 6.0 mEq/L. We used a proportional hazards model to assess factors associated with time to follow-up for episodes of hyperkalemia.
  
  
  RESULTS
  259 of 48,333 serum potassium results met inclusion criteria. The median follow-up time was 3 days; after 30 days, 10% of cases had no follow-up. Residing in the same zip code as the clinic (HR = 1.39; P = .029), degree of hyperkalemia (HR = 2.97; P < .001), and renal insufficiency (HR = 1.41; P = .015) were associated with decreased time to repeat testing. Conversely, African Americans (HR = .51; P = .007) had increased time to repeat testing.
  
  
  CONCLUSIONS
  Follow-up of abnormal laboratory results in outpatients is suboptimal and research is needed to better understand factors that delay follow-up.
authors.affiliation: Division of General Internal Medicine, Department of Medicine, Mount Sinai School of Medicine, New York, NY 10029, USA. carlton.moore@mssm.edu
authors.forename: Carlton
authors.initials: C
authors.lastname: Moore
authors.forename: Jenny
authors.initials: J
authors.lastname: Lin
authors.forename: Thomas
authors.initials: T
authors.lastname: McGinn
authors.forename: Ethan
authors.initials: E
authors.lastname: Halm
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000554:Ambulatory Care Facilities; D003266:Continuity of Patient Care; D005260:Female; D006801:Humans; D006947:Hyperkalemia; D008297:Male; D008485:Medical Audit; D008875:Middle Aged; D009519:New York City; D016016:Proportional Hazards Models; D012720:Severity of Illness Index