Oral anticoagulation does not affect the prevalence of asymptomatic microscopic haematuria: insights from a state-wide sample of patients undergoing elective non-urologic surgery
PrassannahSATASIVAM, Daniel LENAGHAN, Gausihi SIVARAJAH, Benny ZHANG, Jo-Lyn MCKENZIE, Peter CHOONG, Jeremy GOAD, Janelle BRENNAN
St Vincent’s Hospital, Melbourne
Posters Proudly Supported by:
- Urologists are increasingly involved in the management of patients taking oral anticoagulation (OA).
- In May 2012 the American Urological Association (AUA) released new guidelines for the evaluation and management of asymptomatic microscopic haematuria (AMH).
- These guidelines recommend full urologic (and/or nephrologic) evaluation for AMH regardless of the type or level of anticoagulant therapy. The evidence for this recommendation, however, is limited.
- There were 239 male and 357 female patients.
- The average age of patients was 68.4 years.
- Patients with a history of current or prior smoking (n = 245) were no more likely to have AMH than those who had never smoked (16% vs. 18%, p = 0.5).
- 36% of patients were taking OA (n = 216):
- 174 were taking aspirin alone or in combination with other agents
- 39 were taking warfarin
- 13 were taking clopidogrel
- 9 were on newer medications
1. To determine the prevalence of asymptomatic microscopic haematuria (AMH) by examining a cohort of patients undergoing elective non-urological surgery.
2. To determine whether patients taking oral anticoagulation (OA) were more likely to demonstrate AMH on routine urinalysis.
- 17% of patients (n = 104) had AMH.
- The prevalence of AMH was 15% (n = 59) among patients not taking oral anticoagulation and 21% (n = 45) among those who were.
- 596 consecutive patients from Dec ‘11 to Nov ’12.
- Elective hip and knee replacement surgery from ESAS program, chosen because:
- Patients have no known active urological disease
- Similar age group to patients with bladder cancer
- All patients received preoperative MSU
- State-wide coverage of ESAS program allows estimation of true population incidence
- AMH defined as > 100,000 RBCs per litre.
- Prospective data collection – age, sex, smoking status, type of oral anticoagulation if any.
- Statistical significance ascribed to p < 0.05 on Pearson’s Chi-square and Student’s t-tests.
- On multivariate analysis, there was no significant association between the use of any single anticoagulant or combination of agents with the risk of detecting AMH (p = 0.21).
The prevalence of asymptomatic microscopic haematuria is 17% among patients referred for elective joint surgery in the State of Victoria.
The use of oral anticoagulation does NOT increase the risk of asymptomatic microscopic haematuria.
- The prevalence of AMH ranges from 2.4% to 31.1%, based on population studies of over 80,000 individuals.
- Higher rates of AMH are seen in males > 60 years, and those who are current or past smokers.
- Malignancy accounts for only 2.6% to 4% of causes. Other common urological causes include BPH, infection and urinary tract calculi.
- 2012 AUA guidelines on AMH recommend full evaluation in patients on OA. Cuclasure et al (1994) showed no difference in the number of AMH episodes between OA patients (n = 69) and controls (n = 30).
- Our data reinforce the AUA recommendations.
- Davis et al, Diagnosis, Evaluation And Follow-up Of Asymptomatic Microhematuria (AMH) In Adults: AUA Guideline, May 2012
- Rodgers et al, Diagnostic tests and algorithms used in the investigation of haematuria: systematic reviews and economic evaluation. Health Technology Assessment 2006; Vol. 10: No. 18.