Original Papers

Bacterial infections

A clinical prediction rule for urinary tract infections in patients with type 2 diabetes mellitus in primary care

L. M. A. J. VENMANS^a1, K. J. GORTER^a1 c1, G. E. H. M. RUTTEN^a1, F. G. SCHELLEVIS^a2, A. I. M. HOEPELMAN^a3 and E. HAK^a1

^a1 Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands

^a2 Netherlands Institute for Health Services Research NIVEL, Utrecht and Department of General Practice/EMGO Institute VU University Medical Center, Amsterdam, The Netherlands

^a3 Department of Medicine, Division of Internal Medicine and Infectious Diseases, University Medical Center Utrecht, The Netherlands

SUMMARY

We aimed to develop a prediction rule for urinary tract infections (UTIs) in patients with type 2 diabetes mellitus (DM2). A 12-month prospective cohort study was conducted in patients with DM2 aged 45 years to predict the occurrence of recurrent UTIs in women and lower UTIs in men. Predictors for recurrent UTI in women (n=81, 2%) and lower UTIs in men (n=93, 3%) were age, number of general practitioner (GP) visits, urinary incontinence, cerebrovascular disease or dementia. In women, renal disease was an additional predictor. The optimum corrected area under the receiver-operating curve (AUC) was 0·79 (95% CI 0·74–0·83) for women and 0·75 (95% CI 0·70–0·80) for men. Using a cut-off score of 4, women with a lower risk assignment had a probability of 0·3% for the outcome. For a cut-off score of 6, women with a higher risk assignment had a probability of 5·8%. For men these figures were 0·8 and 7·1 for a cut-off score of 2 and 4, respectively. Simple variables can be used for the risk stratification of patients.

(Accepted June 10 2008)

(Online publication July 17 2008)

Key Words:

• Diabetes;
• epidemiology;
• general practice;
• prognosis;
• urinary tract infection

Correspondence:

^c1 Author for correspondence: Dr K. J. Gorter, University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, HPNr. 6.131, PO Box 85500, 3508 GA Utrecht, The Netherlands. (Email: k.j.gorter@umcutrecht.nl)

Footnotes

This study was presented at the ECCMID Congress in Nice, April 2006 (oral presentation).