title: Adherence to guidelines for creatinine and potassium monitoring and discontinuation following renin-angiotensin system blockade: a UK general practice-based cohort study.
abstract: To examine adherence to serum creatinine and potassium monitoring and discontinuation guidelines following initiation of treatment with ACE inhibitors (ACEI) or angiotensin receptor blockers (ARBs); and whether high-risk patients are monitored.
  
  
  
  A general practice-based cohort study using electronic health records from the UK Clinical Practice Research Datalink and Hospital Episode Statistics.
  
  
  
  UK primary care, 2004-2014.
  
  
  
  223 814 new ACEI/ARB users.
  
  
  
  Proportion of patients with renal function monitoring before and after ACEI/ARB initiation; creatinine increase ≥30% or potassium levels >6 mmol/L at first follow-up monitoring; and treatment discontinuation after such changes. Using logistic regression models, we also examined patient characteristics associated with these biochemical changes, and with follow-up monitoring within the guideline recommendation of 2 weeks after treatment initiation.
  
  
  
  10% of patients had neither baseline nor follow-up monitoring of creatinine within 12 months before and 2 months after initiation of an ACEI/ARB, 28% had monitoring only at baseline, 15% only at follow-up, and 47% both at baseline and follow-up. The median period between the most recent baseline monitoring and drug initiation was 40 days (IQR 12-125 days). 34% of patients had baseline creatinine monitoring within 1 month before initiating therapy, but <10% also had the guideline-recommended follow-up test recorded within 2 weeks. Among patients experiencing a creatinine increase ≥30% (n=567, 1.2%) or potassium level >6 mmol/L (n=191, 0.4%), 80% continued treatment. Although patients with prior myocardial infarction, hypertension or baseline potassium >5 mmol/L were at high risk of ≥30% increase in creatinine after ACEI/ARB initiation, there was no evidence that they were more frequently monitored.
  
  
  
  Only one-tenth of patients initiating ACEI/ARB therapy receive the guideline-recommended creatinine monitoring. Moreover, the vast majority of the patients fulfilling postinitiation discontinuation criteria for creatinine and potassium increases continue on treatment.
authors.affiliation: Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.|Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.|Department of Internal Medicine, Regional Hospital of Randers, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Schmidt
authors.affiliation: Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Kathryn E
authors.identifier: 0000-0002-2551-410X
authors.initials: KE
authors.lastname: Mansfield
authors.affiliation: Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Krishnan
authors.initials: K
authors.lastname: Bhaskaran
authors.affiliation: Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Dorothea
authors.initials: D
authors.lastname: Nitsch
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Henrik Toft
authors.initials: HT
authors.lastname: Sørensen
authors.affiliation: Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Liam
authors.initials: L
authors.lastname: Smeeth
authors.affiliation: Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Laurie A
authors.initials: LA
authors.lastname: Tomlinson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D057911:Angiotensin Receptor Antagonists / Q000627:therapeutic use*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D015331:Cohort Studies; D003404:Creatinine / Q000378:metabolism*; D048909:Diabetes Complications / Q000150:complications; D005260:Female; D058006:General Practice; D019983:Guideline Adherence; D006333:Heart Failure / Q000188:drug therapy; D006801:Humans; D006973:Hypertension / Q000188:drug therapy; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy; D011188:Potassium / Q000378:metabolism*; D017410:Practice Guidelines as Topic; D051436:Renal Insufficiency, Chronic / Q000150:complications; D012084:Renin-Angiotensin System / Q000187:drug effects; D012307:Risk Factors; D006113:United Kingdom; D028761:Withholding Treatment
chemical_list: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D003404:Creatinine; D011188:Potassium
keywords: GENERAL MEDICINE (see Internal Medicine); NEPHROLOGY