Vitamin D Fails Again to Affect CV Mortality

December 15, 2011

December 15, 2011 (Aberdeen, Scotland) — A new British study is the latest in a long line of research that has failed to find any impact of vitamin D on cardiovascular-disease mortality [1]. The results also showed no benefit of vitamin D on cancer incidence or mortality, say Dr Alison Avenell (University of Aberdeen, Scotland) et al.

"We don't have the evidence yet to say that this dose of vitamin D can prevent deaths from heart disease or cancer," Avenell told heartwire . She and her colleagues report the long-term follow-up from the placebo-controlled Randomised Evaluation of Calcium or Vitamin D (RECORD) trial online November 23, 2011 in the Journal of Clinical Endocrinology & Metabolism.

Vitamin D has become somewhat of a panacea lately, following the failure of many other vitamins to have any impact on CVD morbidity or mortality, with many patients taking vitamin-D supplements and/or doctors prescribing it, without any real evidence of benefit. One expert has previously told heartwire the situation resembles "a massive uncontrolled experiment."

Avenell agrees with other physicians in the field that the results of large, ongoing trials are needed before any definitive recommendation can be made regarding vitamin-D supplementation. One is the 20 000-patient US Vitamin D and Omega-3 Trial (VITAL) study, results of which won't be available until 2016 or 2017, and the second is the UK Vitamin D and Longevity (VIDAL) trial, which is currently enrolling 1600 patients but plans, in the long run, to recruit as many patients as VITAL, says Avenell.

RECORD Adds to Body of Evidence on Vitamin D: No Benefit on CV Mortality

The RECORD study was conducted in over 5000 people aged 70 or older with a previous low-risk fracture, 85% of whom were women. Participants were randomly allocated into one of four groups: daily vitamin D3 (800 IU), calcium carbonate (1000 mg), both, or placebo for 24 to 62 months, with a follow-up of three years after intervention. The main outcome measures were all-cause mortality, vascular-disease mortality, cancer mortality, and cancer incidence.

Daily vitamin-D supplementation did not significantly affect all-cause and vascular-disease mortality or cancer incidence and mortality in the intention-to-treat (ITT) analysis.

Supplementation with calcium also had no significant effects, in contrast to a systematic review published in 2010, which included earlier data from RECORD that showed an increased risk of MI with calcium, says Avenell.

In a post hoc analysis adjusting for compliance, thus with fewer participants, trends for reduced mortality with vitamin D and increased mortality with calcium "were accentuated, although the results remain nonsignificant," she and her colleagues say.

Hazard Ratio for Mortality, Vascular-Disease Mortality, and Cancer Mortality and Incidence for Vitamin D and Calcium, Compared With Placebo

Outcome With vitamin D or calcium (% with event) Without vitamin D or calcium (% with event) HR, ITT p
Vitamin D        
All deaths 31.6 33.3 0.93 0.132
Vascular deaths 13.2 14.2 0.91 0.175
Cancer deaths 5.7 6.7 0.85 0.157
Cancer incidence 12.8 11.9 1.07 0.376
Calcium        
All deaths 32.9 32.0 1.03 0.46
Vascular deaths 14.2 13.3 1.07 0.333
Cancer deaths 6.6 5.8 1.13 0.249
Cancer incidence 12.6 12.1 1.06 0.485

"Our results add to the body of evidence on nonskeletal benefits from supplementation with vitamin D and calcium and are consistent with the view that, at least for vascular disease and cancer, conclusive evidence for such benefits is absent," they state.

Vitamin-D Supplements to Prevent Osteomalacia in the Housebound

Avenell says she would recommend vitamin-D supplementation in people who are housebound or have little exposure to sunlight, "but this is primarily to prevent osteomalacia." Advice would vary depending upon where in the world the individual is and whether foodstuffs there are fortified with vitamin D, she says.

Coauthor Dr RM Francis (University of Newcastle, UK) has received lecture fees from Shire Pharmaceuticals; all other authors have no relevant conflicts of interest.

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