Cut-Point for Satisfactory Adherence of the Dietary Sodium Restriction Questionnaire for Patients With Heart Failure

Introduction: The low or non-adherence to reduction of sodium intake has been identified among the main precipitating factors of heart failure (HF). The Dietary Sodium Restriction Questionnaire / Questionário de Restrição de Sódio (DSRQ/QRSD), developed in the United States and validated in Brazil for patients with HF, identifies factors that can interfere with adherence to this guidance. However, there is still no cut-point to define satisfactory adherence for patients who answer this questionnaire. Objective: To estimate the cut-point for satisfactory adherence to the DSRQ/QRSD for stable patients on an outpatient basis and decompensated patients in emergency rooms. Methods: Multicenter study. Adult patients diagnosed with heart failure and left ventricular ejection fraction (LVEF) reduced or preserved participate in the study. Patients with HF in outpatient treatment (compensated) and those treated in emergency services due to decompensated acute HF (decompensated) were included. For the cut-point definition, the DSRQ/QRSD scores were compared between compensated and decompensated patients. A ROC curve was constructed for each subscale to determine the best point of sensitivity and specificity regarding adherence. Results: A total of 301 compensated patients and 322 decompensated were included. The mean age was 64 ± 12 years, predominantly male (62%) and mean LVEF of 36 ± 13%. Compensated patients exhibited scores that showed higher adhesion in all subscales (all P < .05). It was determined to be indicative of satisfactory adherence scores ≥40 points from a total of 45 (higher, better adhesion) for the subscale of Attitude and Subjective Norm; ≤ eight of a total of 20 (lower, better adhesion) for Perceived Behavioral Control; and ≤ three of a total of 15 (lower, better adhesion) for Dependent Behavior Control. Conclusion: Based on the evaluation of patients in these two scenarios, it was possible to determine the cut-point for satisfactory adherence to the reduction of sodium in the diet of patients with HF. Countries with similar culture could use this cut-point, as other researchers could also use the results as a reference for further studies.