[Development and evaluation of ExSel Test to screen for excess salt intake in hypertensive subjects]

Development of a test to screen excess salt intake (ESI) in hypertensive patients.

Hypertensive subjects living in Paris area have been included. A 24-hour urinary sodium collection has been performed the day before the visit for a day hospital. A food diary was completed on the day of the urine collection and validated after an interview with a dietetician. An ESI was defined by a urinary sodium ≥ 200mmol/d. Clinical or food characteristics associated to an ESI were retained for the ExSel Test variables. A ROC curve was performed to determine the optimal score for the ExSel Test in detection of ESI in hypertensive patients.

One hundred and forty-eight hypertensive patients have been included living in the Île-de-France area. ESI was observed in 19% with a higher frequency in men. Seven major determinants of ESI have been identified and are the questions that constitute the ExSel Test. A positive response assigns points: man (1); BMI > 30 (2); bread 4 or 5 pieces per day (1) or more than 6 pieces; cheese at least 1 time per day (2); charcuterie at least 2 times per week (2); use of processed broth or pilaf (1); food rich in hidden salt (pizza, cheeseburger, quiche, shrimp, potato chips, smoked fish, olive) at least 2 times per week (1). The ROC curve analysis shows that a score of 5 or more has the best Youden index with a sensitivity of 0.63, specificity of 0.95, PPV of 0.75, NPV of 0.92.

In hypertensive subjects, an excessive salt intake can be detected by the realization of the ExSel Test based only on a simple food-questionnaire and some clinical parameters. For a clinical use of the ExSel Test, an electronic version is available on http://www.comitehta.org.