[Impact of the ExSel(®) test administration on the excessive salt consumption in hypertensive patients followed in general practice]

[Evaluation of the ExSel® self-questionnaire to screen for an excess salt intake in patients followed in a nephrology consultation]

AIM

To evaluate the reliability of the ExSel® self-questionnaire to detect an excess salt intake (≥12g/24h) in patients consulting for hypertension and/or renal failure.

METHODS

Results of the ExSel® self-questionnaire were compared to 24h sodium excretion using the Cohen's kappa test and a Chi² test. Sensitivity, specificity, VPP and VPN were calculated. A ROC curve was realized to find an accurate cut-off.

RESULTS

Mean characteristics of the 101 patients with reliable results were: age of 67±12 years, Body Mass Index 28.4±5.6kg/m², SBP/DBP 139±23/74±13mmHg (98% were hypertensives. Mean salt intake was 7.5±3.1g/24h and mean creatininuria was 13.9±20.1mmol/24h. An excess salt intake (≥12g/24h) was observed in 8% of the patients. The Kappa test at 0.17 and the Chi² at 0.66 signify that the agreement was very low. Sensitivity was 37%, specificity 90%, PPV 20% and NPV 94%. The AUC under the ROC curve was too low (0.665) to determine a threshold adapted to the renal patients.

CONCLUSIONS

The ExSel® autoquestionnaire is not adapted to outpatients, mainly hypertensives (98%) followed in a nephrology consultation to detect an excess salt consumption.