Effectiveness of a simple intervention for prevention of catheter-associated urinary tract infections on a medical hospital unit.

BACKGROUND: Urinary tract infections (UTI) are one of the most common hospital-acquired infections with 80% as a result of urinary catheterisation. AIM/OBJECTIVE: This study examined the impact of a simple intervention consisting of a daily chart reminder in patients with indwelling urinary catheters (IUC) on the duration of catheter use and the incidence of catheter-associated UTIs (CAUTIs). METHODS: The trial used a prospective pretest-post-test design with a control group over a six-month period conducted on two medical units of a community teaching hospital. We included all patients admitted to two medical units between 1 June and 30 November 2016 who had an IUC inserted at the study site. During the intervention phase, a sticker was placed in the charts of patients with urinary catheters reminding physicians to assess for catheter removal if not clinically necessary. RESULTS: A total of 195 patients participated in this study (112 control unit, 83 intervention unit). There was a decrease in the duration of IUC use on the intervention unit from 11.7 days to 7.5 days (P = 0.0028). There was a decrease in repeated catheterisation from 11.1% to 2.1% (P = 0.0882), and CAUTIs from 17.5% to 4.6% (P = 0.0552) but this did not reach statistical significance. DISCUSSION: The implementation of a daily IUC reminder sticker in patient charts was associated with a significant reduction in the mean duration of indwelling catheter use with a trend towards a reduction in the frequency of repeated urinary catheterisation and rate of CAUTIs.

Eliminating systematic bias from case-crossover designs.

Case-crossover designs have been widely applied to epidemiological and medical investigations of associations between short-term exposures and risk of acute adverse health events. Much effort has been made in literature on understanding source of confounding and reducing systematic bias by reference-select strategies. In this paper, we explored the nature of bias in the ambi-directional and time-stratified case-crossover designs via simulation using actual air pollution data from urban Edmonton, Alberta, Canada. We further proposed a calibration approach for eliminating systematic bias in estimates (coefficient estimate, 95% confident interval, and p-value). Bias check for coefficient estimation, size check and power check for significance test were done via simulation experiments to show advantages of the calibrated case-crossover studies over the ones without calibration. An application was done to investigate associations between air pollutants and acute myocardial infarction hospitalizations in urban Edmonton. In conclusion, systematic bias in a case-crossover design is often unavoidable, leading to an obvious bias in the estimated effect and an unreliable p value in the significance test. The proposed calibration technique provides an efficient approach to eliminating systematic bias in a case-crossover study.

BMI, annual blood pressure measurements, and mortality in patients with obesity and hypertension: a retrospective cohort study.

BACKGROUND/OBJECTIVES: In-clinic blood pressure measurement is recommended annually for all hypertensive individuals, but can be difficult to perform in obese patients. We aimed to examine a population-based cohort of obese hypertensive patients to determine whether: (a) BMI was inversely associated with annual blood pressure measurement and (b) performing annual blood pressure measurements was associated with reduced mortality independent of BMI. PATIENTS/METHODS: We carried out a retrospective cohort analysis in 4972 obese hypertensive patients from UK primary care. Multivariable binary logistic regression was used to examine the association between obesity class (class 1=BMI 30-34.9; class 2=35.0-39.9; class 3=40 kg/m or greater) and annual blood pressure measurement. An accelerated failure time multivariable model was used to examine the association between annual blood pressure measurement and mortality. RESULTS: The mean age of the patients was 52.3 ± 9.6 years, the mean BMI was 34.1 ± 4.8 kg/m, and the median follow-up was 13.5 (interquartile range 6.8-20.3) years. A total of 519 (10.4%) patients died. Annual blood pressure measurements were performed in 1605 (47.0%) patients with class 1, 429 (40.2%) with class 2, and 198 (41.1%) with class 3 obesity (P<0.001). Compared with class 1, the covariate-adjusted odds of annual blood pressure measurement was 0.85 [95% confidence interval (CI) 0.73-0.98] for class 2 and 0.87 (95% CI 0.71-1.07) for class 3. Annual blood pressure measurement was associated with an 18.9% (95% CI 9.4-28.3) increase in survival. CONCLUSION: Less than 50% of obese hypertensive patients underwent annual blood pressure measurements and measurements were less frequent in severely obese patients. Annual blood pressure measurement was associated with increased survival. Strategies to improve measurement frequency in obese patients should be implemented.