Table of contents
- Vitamin D supplementation and risk of stroke: A meta-analysis of randomized controlled trials
- VitaminDWiki Stroke category contains
- VitaminDWiki -
8 Stroke Meta-analyses - VitaminDWiki -
7 Stroke Interventions - 10+ types of problems with some meta-analyses:
Vitamin D supplementation and risk of stroke: A meta-analysis of randomized controlled trials
Front Neurol. 2022 Aug 18;13:970111 doi: 10.3389/fneur.2022.970111
Jia Fu 1 , Junfang Sun 2 , Chao Zhang 3Background: Previous observational studies have supported the hypothesis that vitamin D supplementation protects against stroke. However, several current intervention studies contradict this observation. Therefore, we conducted a meta-analysis to investigate further the association between vitamin D supplementation and the risk of stroke.
Methods: This meta-analysis was conducted in accordance with the PRISMA statement and included all the randomized controlled trials (RCTs) that analyzed the relationship between vitamin D supplementation and the risk of stroke. A literature search strategy was established, and the following Medical Search Terms (MeSH) were used: "vitamin D," "Calcitriol," "Calcifediol," "Cholecalciferol," "25-Hydroxyvitamin D 2," "ergocalciferols," "stroke," and stroke-derived terms. We searched for articles published before January 2022 in several databases, namely, PubMed, Web of Science, EMBASE, and The Cochrane Library. We also reviewed references included in relevant published meta-analyses and searched the http://www.ClinicalTrials.gov website for additional RCTs. The Q test and I 2 were utilized to assess the degree of heterogeneity among the studies. Review Manager 5.3 and STATA16.0 software programs were used to assess the literature quality and perform statistical analyses.
Results: In total, twenty-four RCTs (86,202 participants) were included. There was no statistical heterogeneity among the RCTs (I 2 = 0.0%, P = 0.94) included in this meta-analysis. We determined that vitamin D supplementation was not associated with a reduced risk of stroke compared with the placebo (RR = 1.02, 95% CI: 0.93-1.13, P = 0.65). In total, 10 studies only included women, and 14 studies included women and men among the 24 RCTs. Therefore, we performed a subgroup analysis based on sex. After the subgroup analysis, the effect remained statistically insignificant (mixed-sex group: RR = 1.06, 95% CI: 0.93-1.22, P = 0.37, women group: RR = 0.98, 95% CI: 0.86-1.13, P = 0.80). The results were generally comparable, based on age, body mass index (BMI), follow-up period, baseline 25-hydroxyvitamin D (25(OH)D) levels, the designated endpoint, latitude, vitamin D dosage, type of vitamin D administered, and an absence or presence of concurrent calcium supplementation (P > 0.05).
Conclusion: Our study revealed that additional vitamin D supplementation did not reduce the risk of stroke. Therefore, additional RCTs of similar design should not be encouraged to assess any association between vitamin D supplementation and reduced stroke risk.
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VitaminDWiki Stroke category contains
115 items in stroke category - see also Overview Stroke and vitamin D,
Overview Hypertension and Vitamin D Overview Cardiovascular and vitamin DStroke more likely if low Vitamin D
- Stroke 74% less likely if high vitamin D (7,295 women 20-50 years old) – July 2017
- Stroke is 13.5 X more likely if low vitamin D and high blood pressure – March 2015
- Ischemic stroke 17 X more likely if low vitamin D – April 2017
- Stroke is strongly associated with Calcification of cerebral arteries (perhaps low Vitamin D, Vitamin K, Mg…) – March 2018
- Ischemic Stroke 3X more likely if Vitamin D Receptor gene change (Fok 1) – Jan 2014
Post-Stroke worse if low Vitamin D
- Stroke risks increased if low Vitamin D: Death 3.6 X, recurrence 5.5 X – Meta-analysis Nov 2019
- Stroke outcome at 3 months was 3X worse if bad stroke and low vitamin D – Jan 2020
- Death after Ischemic Stroke 2.5 X more likely if less than 10 ng of Vitamin D – May 2019
- Vascular dementia (after strokes) 32X more likely in Hypertensives with low vitamin D – Oct 2015
- Depression following a stroke is 2.7 X more likely if low vitamin D – Sept 2018
- Stroke incidence not associated with low Vitamin D (but stroke outcome is) – Aug 2019
Post-Stroke better if add Vitamin D
- Post-stroke Vitamin D supplementation helped in 11 ways – May 2023
- Improved recovery from ischemic stroke with Vitamin D (300,000 IU injection) – RCT June 2018
- Better outcome following Ischemic stroke if injected with 600,000 IU of vitamin D – RCT Feb 2017
- Ischaemic stroke – Vitamin D doubled survival (Injection followed by monthly 60,000 IU) – RCT Aug 2016
- Stroke patients need more than 2,000 IU of vitamin D (found this time in Japan) – RCT June 2019
Post-Stroke better if Vitamin D actually gets to cells
- Resveratrol fights Parkinson, Alzheimers, Diabetes, Cardiovascular, ALS, Stroke, etc.– Nov 2018
- Stroke rehabilitation (and prevention) requires Vitamin D actually getting to cells – March 2020
9 studies in both categories Depression and Stroke
VitaminDWiki -
8 Stroke Meta-analyses This list is automatically updated
- Recurrent Stroke 5X more-likely if very low vitamin D - meta-analysis Feb 2023
- Ignoring dose size etc, meta-analysis concludes that Vitamin D does not help (stroke risk in this case) – Aug 2022
- Stroke 22 percent more likely if low Vitamin D – meta-analysis July 2021
- Stroke risks increased if low Vitamin D: Death 3.6 X, recurrence 5.5 X – Meta-analysis Nov 2019
- Ischemic Stroke risk reduced by 2.5 if have good level of vitamin D – meta-analysis Feb 2018
- Vitamin D associated with 50 percent less ischemic stroke – meta-analysis Aug 2012
- Cerebrovascular disease 40 percent less likely if high level of vitamin D – meta-analysis Sept 2012
- 50 percent fewer strokes with vitamin D, even though ignored dose size – meta-analysis March 2012
VitaminDWiki -
7 Stroke Interventions This list is automatically updated
- Post-stroke Vitamin D supplementation helped in 11 ways – May 2023
- Post-stroke fatigue cut in half by Vitamin D (just 600 IU daily in 3 months) – Nov 2021
- Stroke patients getting weekly 50,000 IU Vitamin D did better – trial March 2021
- Stroke not prevented by just 2,000 IU of vitamin D plus 840 mg Omega-3 (VITAL) – Feb 2020
- Stroke patients need more than 2,000 IU of vitamin D (found this time in Japan) – RCT June 2019
- Improved recovery from ischemic stroke with Vitamin D (300,000 IU injection) – RCT June 2018
- Ischaemic stroke – Vitamin D doubled survival (Injection followed by monthly 60,000 IU) – RCT Aug 2016
10+ types of problems with some meta-analyses:
- Assumes that as with drugs, the same dose size was given by all trials
Many Meta-analyses actually reject trials that vary the dose size with the person - Assumes that as with drugs, genes do not need to be considered
- Assumes that as with drugs, gut health does not need to be considered
- Assumes that as with drugs, skin-color does not need to be considered
- Assumes that as with drugs, obesity does not need to be considered
- Assumes that as with drugs, co-factors do not need to be considered
- Assumes that as with drugs, assumes daily dosing ( infrequent dosing is often better with Vitamin D)
- Assumes that as with drugs, the same substance was given by all trials
Treats as the same: D3, D2, Calcidiol, oral, injection, topical, nanoemulsion, etc. - Assumes that as with drugs, a loading dose was not even considered
- Assumes that as with drugs, the intervention will act quickly
thus the trial can be completed in a month or so (drugs) , rather 3-9 months (Vitamin D)
There is a big need to develop a meta-analysis for nutrients
Study conclusion: "Therefore, additional RCTs of similar design should not be encouraged to assess any association between vitamin D supplementation and reduced stroke risk".Ignoring dose size etc, meta-analysis concludes that Vitamin D does not help (stroke risk in this case) – Aug 2022835 visitors, last modified 05 Sep, 2022, This page is in the following categories (# of items in each category) - VitaminDWiki -