Cognitive Performance: A Cross-Sectional Study on Serum Vitamin D and Its Interplay With Glucose Homeostasis in Dutch Older Adults

Abstract

This version is distributed under a non-commencial no derivatives Creative Commons (CC-BY-NC-ND) user license, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited and not used for commercial purposes. Further, the restriction applies that if you remix, transform, or build upon the material, you may not distribute the modified material. (25(OH)D) and cognitive performance was examined. Secondly, we assessed 6 whether there was evidence for an interplay between 25(OH)D and glucose 7 homeostasis in the association with cognitive performance. 8 9 Design, Setting and Participants: Associations were studied using cross-10 sectional data of 776 (3 domains) up to 2722 (1 domain) Dutch community-11 dwelling older adults, aged ≥65 years. Results: The overall median MMSE score was 29 synthesis, choline acetyltransferase activity, and amyloid clearance (reviewed 52 in 2-4 ). Finally, besides these direct pathways between vitamin D and cognitive 53 performance, one might also think of indirect pathways. For instance, vitamin 54 D deficiency has been associated with glucose intolerance 6 . Glucose 55 intolerance on its turn has been related to both vascular damage and 56 cognitive decline 7 . Accordingly, it may be that the potential favourable effect 57 of vitamin D on cognitive performance can be partially explained by its 58 beneficial effect on glucose tolerance. It may also be that glucose tolerance 59 biologically interacts with vitamin D. Therefore, it may be that the potential 60 association between vitamin D and cognitive function appears to be stronger 61 5 in persons with glucose intolerance than in their glucose tolerant counterparts. 62These possible pathways, however, have only been examined in a few 63 studies [8][9][10][11][12] . 64 65 So far, results from observational studies 1,[8][9][10][11][13][14][15][16][17][18] Biochemical analyses 142Blood samples were drawn in the morning when the participants were fasted 143 or had consumed a restricted breakfast. Samples were stored at -80 ˚C until 144 determination. Serum 25(OH)D was measured by isotope dilution -online 145 9 solid phase extraction liquid chromatography -tandem mass spectrometry 146 (ID-XLC-MS/MS) 28 . Plasma glucose concentrations were analysed using a 147 hexokinase method (Gluco-quant, Roche Diagnostics). Insulin levels were 148 determined using an immunometric assay (ADVIA Centaur immunoassay 149 system, Siemens Medical Solutions Diagnostics). Creatinine concentration 150 was measured using the enzymatic colorimetric Roche CREA plus assay. 151 152Covariates 153 Height was measured at baseline with a stadiometer to the nearest 0.1 cm. 154Weight was measured to the nearest 0.5 kg with a calibrated analogues scale. association with cognitive performance was tested. In case of significant 213 findings, data was also presented stratified. 214 12 A P-value of <0.05 was used to determine statistical significance. Analyses 215 were performed using the statistical package SAS, version 9.1 (S...

A Systematic Review and Meta‐Analysis of The Effect of Low Vitamin D on Cognition

“…5,7,8,16,27,[36][37][38][39][40][41] Eight studies reported vitamin D as a continuous variable, 5,6,10,27,29,36,39,42 27 as a categorical variable, and three reported both. Seventeen studies used a-priori cut offs 6,8,[14][15][16]28,34,35,37,41,[43][44][45][46][47][48][49] and 13 categorized into tertiles, 9,17,38,50,51 quartiles, 7,12,18,33 or quintiles. 13,40,52,53 The majority of studies analyzed serum 25OHD with four analyzing plasma 25OHD.…”

“…Ten studies classified cognition dichotomously (e.g. decline vs no decline) 9,11,12,17,18,33,43,45,51,53 and 28 reported cognition as a continuous score. Overall, 52 neuropsychological tests were used (Table 1).…”

“…Stroop color-word, 9,42,44,50 Digit Symbol Coding, 7,15,47,49 finger tapping, 7 Symbol Digit Modalities Test, 8,9,46 Trail Making Test A 9,11,27,34,42,47,49 and B, 9,11,18,27,29,33,34,42,44,47,49 Best Symbol-Digit Substitution Test, 16,17,27,28,34,36,39,40,42 serial reaction time, 32,40,42,50 choice reaction time, 30,42 switch-cost reaction time, 32 letter cancelation, 14 Go-no-Go. 44…”

“…Emerging evidence suggests vitamin D deficiency is an important marker of cognitive decline . While the involvement of vitamin D in musculoskeletal health is well‐established, associations with cognitive health have been identified . However, longitudinal evidence remains inconsistent, with some studies reporting cognitive decline related to vitamin D deficiency, whilst others failed to observe associations …”

“…3,4 While the involvement of vitamin D in musculoskeletal health is well-established, associations with cognitive health have been identified. [5][6][7][8][9][10] However, longitudinal evidence remains inconsistent, with some studies reporting cognitive decline related to vitamin D deficiency, [11][12][13][14] whilst others failed to observe associations. [15][16][17][18] Previous reviews and meta-analyses 3,4,19,20 support the association between low vitamin D, poor cognition and risk of cognitive impairment or dementia, 21 however conclusions have been drawn from a small pool of studies (n ≤ 12).…”