DIetary Supplements, Executive funcTions and Vitamin D (DIET-D) (DIET-D)

DIetary Supplements, Executive funcTions and Vitamin D (DIET-D): a Double-blind Randomized Controlled Trial

The purpose of this study is to compare the effect after 12 weeks of the oral intake of Lecitone®Se + 200UI/day of D3 vitamin with the effect of a placebo on changes in cognitive performance in Trial Making Test score part B (this test evaluate executive functions of mental flexibility) in older adults with Mild Cognitive Impairment (MCI).

Current treatments for Alzheimer's disease (AD) are symptomatic and can only temporarily slow down AD without altering its natural evolution. The development of new therapies has primarily focused on preventing the progression of AD. This therapeutic strategy involves being interested in patients with an early stage of AD such as a mild cognitive impairment (MCI). We hypothesized that the combination of Lecitone®Se with 200 IU/day of vitamin D can slow or even improve cognitive decline, particularly executive functions. The primary objective of this trial is to compare the effect after 12 weeks of the oral intake of Lecitone®Se-Vitamin D3 with the effect of a placebo on changes in performance obtained in the TMT B in the older adults with a MCI. The secondary objectives of the study are as follows: To compare the effect after 12 weeks of the oral intake of Lecitone®Se-Vitamin D3 with the effect of a placebo on changes in executive performance in patients with a MCI. To compare the effect after 12 weeks of the oral intake of Lecitone®Se-Vitamin D3 with the effect of a placebo on changes in variability of stride time in patients with a MCI. To compare the effect after 24 weeks of the oral intake of Lecitone®Se-Vitamin D3 with the effect of a placebo and a delay phase of supplementation on changes in executive performance in patients with a MCI. To compare the effect after 24 weeks of the oral intake of Lecitone®Se-Vitamin D3 with the effect of a placebo and a delay phase of supplementation on changes in variability of stride time in patients with a MCI. To determine the compliance and tolerance of the oral intake of Lecitone®Se-Vitamin D3 in patients with a MCI.

80 participants start the oral intake of Lecitone®Se-Vitamin D3 the day after inclusion and during 24 weeks

80 participants in this arm start the oral intake of placebo the day after inclusion and during 12 weeks. Then, they start the oral intake of Lecitone®Se-Vitamin D3 12 weeks after inclusion until the 24th week.

Lecitone®Se-Vitamin D3 is a dietary supplement combining the active ingredients in Lecitone®Se and 100 IU of vitamin D3. This dietary supplement comes in capsule form. Participants take 2 capsules of Lecitone®Se -Vitamin D3 per day. The dose of vitamin D supplementation will not be adjusted except in case of an adverse event such as hypercalcemia. In this case, vitamin D supplementation is stopped and the participant is released prematurely from the study.

The comparator is represented by placebo capsules of identical appearance (same size, same color and same smell) that Lecitone®Se-Vitamin D3 capsules.

Inclusion Criteria: Age ≥ 60 years Memory complaints No dementia (DSM-IV, NINCDS-ADRDA negative) No depression (Geriatric Depression score ≤ 5/15) Ability to walk a distance of 15 meters unaided Diagnosis of MCI To have hypovitaminosis D (i.e. serum 25-hydroxyvitamin D [25OHD]concentration ≤ 30ng/mL) To have no hypercalcemia (defined as serum calcium concentration ≥ 2,65mmol/L) To have given and signed an informed consent to participate in the trial To be affiliated to French Social Security Exclusion Criteria: Others cognitive disorders (untreated thyroid dysfunction, chronic ongoing ethylism, history of syphilis, stroke, severe depressive symptomatology (Geriatric Depression score > 5/15), existence of dementia according to DSM-IV and NINCDS-ADRDA criteria at the time of inclusion) Vitamin D supplementation during inclusion Contraindications to vitamin D Unstable medical condition Enrollment in another simultaneous clinical trial Civil defense measures underway