An Evaluation of the Effect of Vitamin D Supplementation on the Cognitive Function of Older Subjects With Low Levels of This Vitamin

Background: Ageing is associated with an increased risk of cognitive decline and depression. Vitamin D plays an important role in many of the symptoms and conditions related to advanced age, including impaired balance, falls and osteoporosis. Vitamin D also has a physiological effect on the function of the central nervous system, and studies have suggested a relationship between this vitamin and changes in affect and cognitive function in the elderly. The investigators propose a pilot study to examine the relationship between below-normal levels of Vitamin D to affective symptoms and specific cognitive functions in the elderly.

Methods: A total of 30 subjects of both genders older than 65 years with levels of 25-OH Vitamin D lower than 30 ng/ml on routine laboratory screening will be referred by the treating family physicianfor screening. Subjects will be required to provide written informed consent for inclusion in the study. Exclusion criteria will include any active or unstable medical condition as determined by the treating physician, known neurocognitive disorder, known affective disorder, the use of any class of antidepressant drugs, the use of supplements containing vitamin D in any dose, significant visual or hearing impairment not corrected by spectacles or hearing aids, and a level of literacy that limits cognitive ability. All subjects will undergo cognitive screening by use of the MoCA test, computerized cognitive assessment using the the Neurotrax (®Mindstreams) computerised cognitive assessment battery, and the 15-item Geriatric Depression Scale. All subjects will undergo repeat testing for level of 25-OH Vitamin D, and where below-normal levels are confirmed patients will receive a supplemental monthly oral dose of 60000 units Vitamin D administered by a nurse for a period of 3 months. At 3 months subjects will undergo repeat testing for level of 25-OH Vitamin D, and repeat computerized cognitive assessment using the Neurotrax Mindstreams battery and the 15-item Geriatric Depression Scale (GDS).

Background: Ageing is associated with an increased risk of cognitive decline and depression. Vitamin D plays an important role in many of the symptoms and conditions related to advanced age, including impaired balance, falls and osteoporosis. Vitamin D also has a physiological effect on the function of the central nervous system, and studies have suggested a relationship between this vitamin and changes in affect and cognitive function in the elderly. The investigators propose a pilot study to examine the relationship between below-normal levels of Vitamin D to affective symptoms and specific cognitive functions in the elderly.

Methods: A total of 30 subjects of both genders older than 65 years with levels of 25-OH Vitamin D lower than 30 ng/ml on routine laboratory screening will be referred by the treating family physicianfor screening. Subjects will be required to provide written informed consent for inclusion in the study. Exclusion criteria will include any active or unstable medical condition as determined by the treating physician, known neurocognitive disorder, known affective disorder, the use of any class of antidepressant drugs, the use of supplements containing vitamin D in any dose, significant visual or hearing impairment not corrected by spectacles or hearing aids, and a level of literacy that limits cognitive ability. All subjects will undergo cognitive screening by use of the MoCA test, computerized cognitive assessment using the the Neurotrax (®Mindstreams) computerised cognitive assessment battery, and the 15-item Geriatric Depression Scale. All subjects will undergo repeat testing for level of 25-OH Vitamin D, and where below-normal levels are confirmed patients will receive a supplemental monthly oral dose of 60000 units Vitamin D administered by a nurse for a period of 3 months. At 3 months subjects will undergo repeat testing for level of 25-OH Vitamin D, and repeat computerized cognitive assessment using the Neurotrax Mindstreams battery and the 15-item Geriatric Depression Scale (GDS).

Study Type: An open-label prospective pilot interventional study

Study Design: the one group pretest-posttest design.

Eligibility Criteria:
Inclusion Criteria:

* Adults aged 65 years and older.
* Level of vitamin D (25-OH vitamin D) is less than 30 ng / ml.
* Stable health status as assessed by the treating primary care physician.
* Do not take antidepressant medications.
* Do not take supplements containing vitamin D.
* Normal cognitive function as determined by MoCA Test screening and clinical assessment
* Adequate literacy to enable the performance of assessment instruments
* Provide informed consent as required by the Ethics Committee.

Exclusion Criteria:

* Age younger than 65 years
* Health status not stable as determined by the treating primary care physician
* Cognitive impairment or dementia
* Illiteracy
* Taking supplements containing Vitamin D
* Taking antidepressant medications
* Significant visual or hearing impairment not corrected by spectacles or hearing aids
* Impaired competency limiting the subject's ability to provide informed consent