Educational Intervention for Sodium Restriction in Patients With Hypertension

The Effectiveness of an Educational Intervention for Sodium Restriction in Patients With Hypertension: Study Protocol for a Randomized Controlled Trial

This parallel, randomized clinical trial will include 120 participants. They will be allocated to a sodium restriction educational intervention or usual care groups. The educational intervention will be planned based on the DSRQ application and sessions will be conducted once a month for the period of six months. Both spot urine collection to estimate sodium intake and the DSRQ will be applied at the baseline, in the eighth week and at the end of the follow-up. Blood sample and 24-hour ambulatory blood pressure monitoring (ABPM) will be conducted at the beginning and at the end of the follow-up. Anthropometric measurements, blood pressure measurement and 24-hour food recall will be collected during follow-up.

This parallel, randomized clinical trial will include 120 participants. They will be allocated to a sodium restriction educational intervention or usual care groups. The educational intervention will be planned based on the DSRQ application and sessions will be conducted once a month for the period of six months. Both spot urine collection to estimate sodium intake and the DSRQ will be applied at the baseline, in the eighth week and at the end of the follow-up. Blood sample and 24-hour ambulatory blood pressure monitoring (ABPM) will be conducted at the beginning and at the end of the follow-up. Anthropometric measurements, blood pressure measurement and 24-hour food recall will be collected during follow-up. The study 'The effectiveness of an educational intervention to sodium restriction in patients with hypertension' is based on the results of the DSRQ application, whose objective is to evaluate aspects related to non-adherence to the recommendation of a low-sodium diet, identifying adherence barriers and facilitators, contributing to the planning of interventions for improving the adoption of a low-sodium diet and, consequently, better hypertension control.

Sodium restriction, Dietary sodium restriction questionnaire (DSRQ), Low-sodium diet, Adherence, Educational intervention

Participants assigned to the educational intervention group will have dietitian consultation to receive a dietary planning based on diet rich of fruits, vegetables, low fat, low processed foods and high nonfat dairy. During six months they will have monthly dietitian appointments including educational sessions to stimulate sodium restriction and enhance to follow the dietary planning. Each 15 days they will be contacted by phone to reinforce adherence to sodium restriction diet.

Participants assigned to the control group will have a dietitian consultation receiving general recommendations for hypertension, such as increasing the consumption of fruits and vegetables, reducing salt intake, avoiding processed and high-sodium foods, reducing body weight if BMI> 25Kg/m2 and limiting consumption of alcoholic beverages. They will be provided with an explanatory folder about hypertension. During six months, participants assigned to the control group will be monitored in monthly visits to the dietitian without modifying their usual care

The educational intervention sessions will be conducted face-to-face, one hour-long and with the aim to encourage and motivate the low-sodium diet adherence. The dietitian's approaches will provide individual skills to achieve the goals (sodium restriction), developing changes in behavior and monitoring the progress towards the skills needed to reduce patient's barriers and difficulties for sodium restricted diet adherence.

Participants assigned to the control group will have a dietitian consultation receiving general recommendations for hypertension, such as increasing the consumption of fruits and vegetables, reducing salt intake, avoiding processed and high-sodium foods, reducing body weight if BMI> 25Kg/m2 and limiting consumption of alcoholic beverages. They will be provided with an explanatory folder about hypertension. During six months, participants assigned to the control group will be monitored in monthly visits to the dietitian without modifying their usual care

Changes from baseline, after 8 weeks and 6 months in Dietary Sodium Restriction Questionnaire (DSRQ) score

Questionnaire sensitivity and specificity by the comparison of Dietary Sodium Restriction Questionnaire (DSRQ) scores to urinary sodium values

Inclusion Criteria: female and male individuals, ageing from 40 to 80 years old, in treatment and monitored at the hypertensive outpatient department of HCPA. Participants must not have been monitored by a nutritionist or followed a nutritional orientation for over than six months Exclusion Criteria: pregnancy or lactating; gastrointestinal tract disease; inflammatory disease; chemotherapy treatment; diabetes diagnosis; incapacity to follow an interview and/or to participate in the intervention program without the need of a third party involvement

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