Vitamin D status is associated with executive function a decade later: Data from the Women's Healthy Ageing Project

Alicia M Goodwill; Stephen Campbell; Steven Simpson Jr; Maria Bisignano; Cherie Chiang; Lorraine Dennerstein; Cassandra Szoeke

doi:10.1016/j.maturitas.2017.10.005

Vitamin D status is associated with executive function a decade later: Data from the Women's Healthy Ageing Project

Maturitas. 2018 Jan:107:56-62. doi: 10.1016/j.maturitas.2017.10.005. Epub 2017 Oct 4.

Authors

Alicia M Goodwill¹, Stephen Campbell², Steven Simpson Jr¹, Maria Bisignano³, Cherie Chiang³, Lorraine Dennerstein⁴, Cassandra Szoeke⁵

Affiliations

¹ Institute for Health and Ageing, Australian Catholic University, Melbourne, Australia; Department of Medicine (Royal Melbourne Hospital), University of Melbourne, Parkville, Australia.
² Australian Healthy Ageing Organisation, Parkville, Victoria, Australia; Melbourne Health, Royal Melbourne Hospital, Parkville, Australia.
³ Melbourne Health, Royal Melbourne Hospital, Parkville, Australia.
⁴ Department of Psychiatry, University of Melbourne, Parkville, Australia.
⁵ Institute for Health and Ageing, Australian Catholic University, Melbourne, Australia; Department of Medicine (Royal Melbourne Hospital), University of Melbourne, Parkville, Australia. Electronic address: cszoeke@unimelb.edu.au.

PMID: 29169581
DOI: 10.1016/j.maturitas.2017.10.005

Abstract

Objectives: Vitamin D deficiency has been associated with cognitive decline and dementia in older adults. However, there is a paucity of studies assessing whether this association manifests from midlife. Given the long prodromal stage of dementia, we investigated the association between midlife vitamin D and cognition 10 years later.

Study design: 252 participants (aged 55-67 years) from the Women's Healthy Ageing Project had baseline (2002) vitamin D and neuropsychological measures assessed. Of these, 170 (aged 65-77 years) had follow-up neuropsychological testing (2012).

Outcome measures: Serum 25-hydroxyvitamin D (25[OH]D) was measured using an automated chemiluminescence system. The neuropsychological tests used were: Consortium to Establish a Registry for Alzheimer's Disease (CERAD), California Verbal Learning Test Second Edition (CVLT-II), verbal fluency and Trail Making Test-B (TMT-B). Composite scores for verbal episodic memory (CERAD and CVLT-II) and executive function (verbal fluency and TMT-B) were obtained by summating standardized scores for each test.

Results: Analyses were adjusted for age, education and body mass index (BMI). Further adjustment for physical activity, depression, vascular risk factors, supplementation and APOE4-genotype did not materially change the results. At baseline, those with vitamin D>25nmol/L performed better on verbal fluency (β=2.46, 95%CI=0.53,4.40) and TMT-B time (β=-18.23, 95%CI=-32.86,-3.61), with higher executive function (β=1.40, 95%CI=0.44,2.37). These relationships persisted 10 years later for TMT-B (β=-15.38, 95%CI=-30.82,0.07) and executive function (β=1.05, 95%CI=0.14,1.95). There were no associations with tests of verbal episodic memory.

Conclusion: Midlife vitamin D>25nmol/L is associated with improved aspects of executive function in ageing. Findings highlight a potential therapeutic age window where midlife vitamin D repletion could be neuroprotective against cognitive decline.

Keywords: Ageing; Cognition; Executive function; Memory; Neuropsychology; Vitamin D.

MeSH terms

Aged
Cognition
Cognitive Dysfunction / prevention & control
Executive Function*
Female
Healthy Aging / blood*
Humans
Memory, Episodic
Middle Aged
Neuropsychological Tests
Vitamin D / analogs & derivatives*
Vitamin D / blood
Vitamins / blood*

Substances

Vitamins
Vitamin D
25-hydroxyvitamin D