Clinical trial NCT02121457: Brazil Nuts Effects on Selenium Status and Cognitive Performance
Official title: Effects of Brazil Nuts Consumption on Selenium Status and Cognitive Performance in Older Adults With Mild Cognitive Impairment: a Randomized Controlled Pilot Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Mild Cognitive Impairment
Keywords: cognitive performance
selenium
brazil nuts
oxidative stress
Lead sponsor: University of Sao Paulo
Sponsor class: OTHER
First posted: 2014-04-23
Enrollment: 31
Sex: ALL
Minimum age (years): 60
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Some studies reported that selenium status is associated with cognitive function. However only a few reports have investigated whether selenium supplementation can benefit cognitive performance and in most of them selenium supplementation was not exclusive. Also, none of those reports have used foods rich in selenium as a source of supplementation. Thus, the aim of our study was to investigate whether the consumption of Brazil nuts improves cognitive function. We hypothesized that the daily consumption of Brazil nuts would have benefits on selenium status, increase antioxidant enzyme activity and improve cognitive function in older adults with MCI.

Detailed description: We enrolled older patients with MCI who attended the Memory and Aging Unit of the Geriatrics Division, University of São Paulo Medical School (Brazil). All participants fulfilled the criteria proposed by the International Working Group on Mild Cognitive Impairment (Winblad et al., 2004), which include the following: (1) the person is neither normal nor demented; (2) there is evidence of cognitive deterioration shown by subjective report in conjunction with objective cognitive deficits; and (3) activities of daily living are preserved and complex instrumental functions are either intact or minimally impaired. The diagnosis of MCI was based on a comprehensive neuropsychological assessment which included the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological battery (Welsh et al., 1994; Bertolucci et al., 2001). Participants were recruited from May 2011 to August 2012. Eligible subjects were aged 60 years or older, fluent in Portuguese, and free of any other significant neurologic or psychiatric diseases. None of them presented major depression or psychosis, had a regular intake of Brazil nuts, used supplements with selenium, or had intolerance to oleaginous food. An informed consent was obtained before the interview from all participants. The research protocol was approved by the Research Ethics Comittee of the Faculdade de Ciências Farmacêuticas da Universidade de São Paulo.

Eligibility criteria: Inclusion Criteria:

* aged 60 years or older,
* fluent in Portuguese,
* free of any other significant neurologic or psychiatric diseases

Exclusion Criteria:

Primary outcomes:
measure: Selenium level in plasma and erythrocyte
timeFrame: 6 months
Secondary outcomes:
measure: cognitive performance
timeFrame: 6 months
Other outcomes:
measure: Oxidative stress parameters
timeFrame: 6 months
Locations:
city: São Paulo
country: Brazil
facility: University Of são Paulo
state: SP
Study officials:
affiliation: University of Sao Paulo
name: Silvia F Cozzolino, PhD
role: STUDY_DIRECTOR
References: