GAit, MEmory, Dietary and Vitamin D

Study Overview
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Brief Summary
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Gait and posture disorders are very common in subjects aged 65 and over, and result mainly from neuromuscular and cognitive disorders. Many studies have shown that 1) vitamin D deficiency is very common in women aged 65 and over, 2) individuals with hypovitaminosis D have lower muscle, gait and executive performances and are more prone to fail than individuals with no hypovitaminosis D, 3) the intake of vitamin D combined or not with calcium may improve muscle strength and cognitive performance. The investigators hypothesized that the daily intake of 2 yogurts containing 200 IU of vitamin D and 400 mg of calcium 1) can improve spatiotemporal gait parameters, posture and executive performance, 2) and that this improvement depends of the initial level of vitamin D deficiency.

Official Title
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Dairy Product, Calcium & Vitamin D Supplementation and Cognitive-motor Function

Conditions
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Memory Complaint Without Cognitive Decline

Intervention / Treatment
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* Dietary Supplement: Yogurt supplemented with vitamin D and calcium
* Dietary Supplement: Yogurt not supplemented with vitamin D and calcium


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Woman aged 65 and over 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) Ability to walk a distance of 15 meters unaided Ability to eat 2 yogurts per day Memory complaint without cognitive decline To have given and signed an informed consent to participate in the trial To be affiliated to French Social Security To have no vitamin D supplementation during inclusion Exclusion Criteria: Existence of dementia according to DSM-IV and NINCDS-ADRDA criteria and others cognitive disorders: untreated thyroid dysfunction, chronic ongoing ethylism, history of syphilis, stroke with sequelae, depressive symptomatology (Geriatric Depression Scale > 5/15) Osteoarticular diseases of the lower members and / or spine altering the biomechanical characteristics of the body. Vitamin D supplementation during inclusion Contraindications to vitamin D Unstable medical condition Dairy allergy Taste of dairy products not supported Enrolment in another simultaneous clinical trial Civil defense measures underway Refusal to participate of the subject

Ages Eligible for Study
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Minimum Age: 65 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Yogurt supplemented with vitamin D and calcium<br>20 participants take yogurt supplemented with vitamin D and calcium during 12 weeks | Dietary Supplement: Yogurt supplemented with vitamin D and calcium<br>* The product is a yogurt containing 200 IU of vitamin D and 400 mg of calcium. Participants take 2 yogurts per day.<br>|
| Active Comparator: Yogurt not supplemented with vitamin D and calcium<br>20 participants take yogurt not supplemented with vitamin D and calcium during 12 weeks | Dietary Supplement: Yogurt not supplemented with vitamin D and calcium<br>* The comparator is represented by a yogurt not supplemented with vitamin D and calcium.Participants take 2 yogurts per day.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in spatiotemporal gait, and in particular in the variability of stride time | Stride time variability is measured with spatiotemporal analysis of walking | This outcome is assessed at baseline and 12 weeks after oral intake. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in posture | Posture is evaluated with Time Up & Go, Five Time Sit-to-Stand and posture analysis with a platform. | This outcome is assessed at baseline and 12 weeks after oral intake. | 
| Change in grip strength | Grip strength is measured with a dynamometer. | This outcome is assessed at baseline and 12 weeks after oral intake. | 
| Change in executive performance | Executive performance is measured with Trial Making Test part B (TMT B) | This outcome is assessed at baseline and 12 weeks after oral intake. | 
| Change in other cognitive scores | Executive scores are assessed with digit span test (forward and backward), Trial Making Test part A (TMT A), Stoop test and Processing Speed Index | These outcomes are assessed at baseline and 12 weeks after oral intake. | 
| Change in the serum concentration of 25 OHD | This outcome is assessed with the serum concentrations of 25OHD | This outcome is assessed at baseline and 12 weeks after oral intake. | 
| Compliance to intervention | Compliance is measured by the number of yogurt capsules returned | This outcome is assessed 12 weeks after oral intake. |