Adherence to the Mediterranean Diet and Urinary Sodium Excretion in people at high risk of dementia

Abstract Background Both adequate sodium intake and adherence to the Mediterranean Diet (MedDiet) are largely described as important factors for the prevention and control of hypertension and cerebrovascular diseases. However, data regarding sodium intake in the MedDiet is scarce. This study aims to quantify the association between the MedDiet adherence and sodium excretion. Methods This cross-sectional analysis was carried out under the MIND-Matosinhos randomized controlled trial, a community-based program for Portuguese adults at high risk of dementia. The adherence to the MedDiet was assessed through the Portuguese version of the Mediterranean Diet Adherence Screener questionnaire, and a score ≥10 indicated a high adherence. A 24h urine collection was used to evaluate creatinine and sodium excretion. Excessive sodium excretion was defined as ≥ 2000 mg/day. Sociodemographic, lifestyle and health-related data were obtained through structured questionnaires. The association between the adherence to the MedDiet and urinary sodium excretion (recoded into two categories by the median) was quantified by calculating Odds Ratios (OR) and respective 95% Confidence Intervals (95% CI) using a binary logistic regression. Results A total of 126 individuals (24 to 83 years old; median age of 70.0) was included in this study (58.7% female). High adherence to the MedDiet was observed among 15.9% of the sample whereas excessive sodium excretion was reported by 84.1%. After adjusting for confounders, participants with high adherence to the MedDiet showed a higher sodium excretion (OR = 4.05; 95% CI: 1.33-12.37). Conclusions A high adherence to the MedDiet was associated with a higher sodium excretion. Thus, an increased adherence to this dietary pattern seems to have limited effects on the adequacy of sodium intake. This highlights the importance of public health measures to reduce sodium intake when following a MedDiet namely by improving consumer empowerment. Key messages • Despite the well-known protective effect of the Mediterranean Diet on hypertension and cerebrovascular diseases, the role of sodium intake within this dietary pattern is still understudied. • The Mediterranean Diet can be an important source of hidden sodium, which enhances the need to invest in public health measures to reduce sodium intake, namely through culinary medicine education.