Marion Tomičić

Deep breathing: A simple test for white coat effect detection in primary care

Abstract Aim. White coat hypertension (WCH) is hard to differentiate from sustained hypertension without the use of 24-h ambulatory blood pressure monitoring (ABPM). This invaluable procedure is nevertheless cumbersome and expensive. A simple test of deep breathing over 30 s (DBT) was proposed as a method to unveil WCH. Methods. Two hundred and fourteen outpatients referred for the evaluation of uncontrolled hypertension (blood pressure, BP > 140/90 mmHg despite therapy) were enrolled in a controlled clinical trial. The examinees were randomly divided in two groups: control (n = 108; sequential standard BP measurement only) and intervention (n = 106; the same+DBT), using ABPM as the reference standard. Results. The relative decrease in BP was significantly larger in the intervention group than in the control group, by 15/4 mmHg (p = 0.005). The best detection of WCH was obtained at ≥ 15% systolic BP reduction following DBT, with a positive predictive value of 94.0% (95% CI 72.0–100.0). BP reduction of ≤ 8% may rule WCH out with a negative predictive value of 78.4% (95% CI 64.0 – 85.9). Conclusion. DBT is a reliable, inexpensive and fast test for the detection of WCH in primary care.

Salt intake is persistently reduced by emphasized warning: Long-term results of a controlled trial

Excessive salt intake is a major cardiovascular risk factor. The main source of sodium in transitional and developing countries is not the processed food but salt added during the cooking procedure or at the table. The objective of this trial was to examine the impact of home salt containers’ labeling on daily salt intake. A sample of treated hypertensives (N= 139) was randomized in two groups, one receiving just a leaflet about the harmful effects of excessive salt consumption (control, N= 69), and the other one receiving in addition self-adhesive warning stickers for household salt containers (intervention, N= 70). Blood pressure (BP) and 24-hour urinary sodium excretion (Na24) were measured in all the subjects at the start of the trial, and 1, 2 and 12 months later. The average starting Na24 was 211.1±78.7 mmol, similar in both groups. One, two, and twelve months later a significant decrease in Na24 was observed in the intervention group (to 183.5±51.6 mmol; P <0.001) as opposed to the control group (to 206.5±60.4 mmol; P= 0.19). Initial BP steadily decreased by some 5.7/2.2 mm Hg (P<0.001) in the intervention group, and by 0.8/0.5 mm Hg among the controls (P>0.286). It is concluded that a marked, long-lasting reduction in Na24 and BP may be achieved with warning labels on harmful effects of excessive salt intake. Correspondence to: Dr. Zvonko Rumboldt, MD, PhD, Split University School of Medicine, Šoltanska 2, 21000 Split, Croatia; Tel: +385 21 557828; Fax: +385 21 465304; E-mail: zr@mefst.hr