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CARDIOLOGY
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Evidence indicates that
atherosclerosis is an
inflammatory condition.
Vitamin D deficiency leads to
a state of hyperparathyroidism
and inflammation documented
by increased levels of C-reactive
protein and increased levels of
Interleukin-10.
Vitamin D levels were
found to be low in mood
disorders and depression
is currently regarded as an
important risk for ischemic
heart disease, although this link
needs more study.
6
Vitamin D deficiency and
cardiovascular disease:
epidemiological studies
In many large observational
studies, at least 10, it was
shown that low vitamin D
levels were associated with
an increase in cardiovascular
disease. Recently two large
studies with long-term
follow-up were published.
In the Copenhagen City
Heart Study, 10 170 men and
women were followed for 29
years for heart disease. It was
demonstrated that low vitamin
The Specialist Forum | Vol. 17 No. 4
D levels were associated with a
64% higher risk for myocardial
infarction and a 57% risk of
early death. The authors added
this study to a meta-analysis
which showed a 40% increased
risk of heart disease associated
with low vitamin D levels.
In the Whitehall study, with
5409 older men followed for
13 years, it was shown that
low vitamin D levels were
linearly related to an increase in
heart disease.
They showed that doubling
of the vitamin D level was
associated with a reduction
of 20% in vascular mortality
and a reduction of 23% in
non-vascular mortality. They
also did a meta-analysis of
12 prospective studies which
showed that high levels of
vitamin D as compared to low
levels had a 21% lower vascular
mortality and a 28% lower
total mortality.
Vitamin D effects
of treatment
Autier et al. showed in a meta-
analysis of 18 randomised
controlled trials with a
observation period of 5.7 years
that vitamin D reduced all-
cause mortality by 7% (95%CI:1-
13%) but did not impact on
myocardial infarction or stroke.
In another meta-analysis by
Elamin et al. of 51 trials, vitamin
D therapy did not reduce death,
myocardial infarction, or stroke:
R.R 0.96 (95%CI: 0.93-1.00)
for mortality.
In a Cochrane meta-analysis
of 50 trials, it was shown that
all-cause mortality was not
reduced by vitamin D: Relative
Risk Reduction 3% (95%CI: 0
to 6%). However, vitamin D3
(cholecalciferol) did reduce all-
cause mortality by 6% (95%CI:
2 to9%) with number needed-
to-treat of 161(95%CI:107-481)
while vitamin D2 (ergocalciferol)
did not have an effect.
Future directions
A major double-blind
randomised placebo-
controlled trial is underway
and has enrolled 25 000 men
and women: the VITAL trial
(Vitamin D and OmegA-3 triaL).
Participants are to receive
2000IU of vitamin D or placebo
and 1gram per day of fish oil for
five years.
There is as yet no
randomised trial testing the
effect of vitamin D on heart
disease in the elderly.
Conclusions
1
Vitamin D is often deficient
in patients especially in
the elderly and in people with
myocardial infarction.
Vitamin deficiency
may contribute to
atherosclerosis through
several mechanisms.
Vitamin D deficiency is
common and is linked to
an increase in cardiovascular
disease worldwide.
Although treatment of
vitamin D deficiency is
relatively easy, there are
not enough randomised
clinical trials to advise
specific treatment in specific
dose of vitamin D for the
individual patient.
Sunlight every day for
ten minutes on the arms
and legs remains an effective
way to increase vitamin D
levels. SF
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May 2017
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