J Am Coll Cardiol. 2016 Jun 7;67(22):2593-603. doi: 10.1016/j.jacc.2016.03.508.
Witte KK1, Byrom R2, Gierula J2, Paton MF2, Jamil HA2, Lowry JE2, Gillott RG3, Barnes SA3, Chumun H2, Kearney LC2, Greenwood JP2, Plein S2, Law GR2, Pavitt S4, Barth JH5, Cubbon RM2, Kearney MT2.
- Many studies consider daily Vitamin D supplementation to plateau by 2 months
- This is one of several studies which show plateauing does not occur until 3-6 months
- Wonder if a quick (2 month) plateau is only associated with one of the following
- Healthy adults
- Young adults
- Vitamin B6 sufficient
(B-6 deficiency slowed the response to vitamin D repletion - 1990)
- Response time is very important for pregnancy supplementation studies
- VitaminDWiki recommends a loading dose to plateau in about a week instead of 12-20 weeks
Overview Loading of vitamin D
- Bone health not improved in 2 months of Vitamin D (need 6 months or loading dose) – RCT April 2017
- 4,000 IU of Vitamin D daily is safe, but takes a year to plateau (Best-D) – RCT Dec 2016 age >65, probably with osteoporosis
- Heaney 2003: 38 years old, healthy, men
Download the Heany 2003 PDF from VitaminDWiki
Patients with chronic heart failure (HF) secondary to left ventricular systolic dysfunction (LVSD) are frequently deficient in vitamin D. Low vitamin D levels are associated with a worse prognosis.
The VINDICATE (VitamIN D treatIng patients with Chronic heArT failurE) study was undertaken to establish safety and efficacy of high-dose 25 (OH) vitamin D3 (cholecalciferol) supplementation in patients with chronic HF due to LVSD.
We enrolled 229 patients (179 men) with chronic HF due to LVSD and vitamin D deficiency (cholecalciferol <50 nmol/l [<20 ng/ml]). Participants were allocated to 1 year of vitamin D3 supplementation (4,000 IU [100 μg] daily) or matching non-calcium-based placebo. The primary endpoint was change in 6-minute walk distance between baseline and 12 months. Secondary endpoints included change in LV ejection fraction at 1 year, and safety measures of renal function and serum calcium concentration assessed every 3 months.
One year of high-dose vitamin D3 supplementation did not improve 6-min walk distance at 1 year, but was associated with a significant improvement in cardiac function (LV ejection fraction +6.07% [95% confidence interval (CI): 3.20 to 8.95; p < 0.0001]); and a reversal of LV remodeling (LV end diastolic diameter -2.49 mm [95% CI: -4.09 to -0.90; p = 0.002] and LV end systolic diameter -2.09 mm [95% CI: -4.11 to -0.06 p = 0.043]).
One year of 100 μg daily vitamin D3 supplementation does not improve 6-min walk distance but has beneficial effects on LV structure and function in patients on contemporary optimal medical therapy. Further studies are necessary to determine whether these translate to improvements in outcomes. (VitamIN D Treating patIents With Chronic heArT failurE [VINDICATE]; NCT01619891).