What are Statins?
There could be a relationship between
two completely different entities – statin drugs used
in the treatment of high cholesterol levels and vitamin D, a
hormone that keeps our bones strong, suggests researchers.
Statins are a group of drugs that are
used to treat high blood cholesterol levels and include simvastatin,
lovastatin, atorvastatin, rosuvastatin, fluvastatin, pravastatin and
pitavastatin. These cholesterol-lowering medications
block HMG-CoA reductase, an important enzyme that mediates the
formation of cholesterol by the liver, thereby reducing the levels of bad
cholesterol or LDL (low density lipoprotein)-cholesterol in the blood.
Statins are used to prevent cardiovascular
diseases like heart attacks and certain strokes, either before they occur, or
after they occur to prevent further episodes. They should not be used during
pregnancy or breastfeeding, in those with an active liver disease or on those
who are allergic to the medications.
how to repair heart muscle damage
A serious statin-related side effect is damage to
muscles, termed as rhabdomyolysis, which can progress to acute kidney
failure. Statins may also cause liver dysfunction. They should be used with
caution along with other drugs which could precipitate the development of
rhabdomyolysis.
Vitamin D is a hormone that is produced by the skin
on exposure to sunlight and is also obtained from dietary sources. The active
form of vitamin D helps to absorb calcium and maintain strong bones. Deficiency
of vitamin D results in a condition called osteomalacia in adults and
rickets in children, which should be treated with vitamin D supplements.
The function of vitamin D is not only limited to bone formation. Deficiency of
vitamin D has been associated with conditions like cancers, depression,
inflammation and heart disease; although currently there is no adequate proof
that the deficiency causes these conditions for sure.
What is the Relationship between Statins and Vitamin D?
Current evidence indicates a
complex relationship between statins and vitamin D, with studies coming up with
conflicting results. Unless large and reliable studies are conducted to
specifically study the relationship, many questions, like the ones below, will
remain inadequately answered.
1. Do statins cause
vitamin D deficiency?
Cholesterol is required
to produce vitamin D by the skin in the presence of sunlight. Cholesterol is
converted into 7-dehydrocholesterol, which is then converted to the
active form of vitamin D in the presence of sunlight.
Taking the above into
consideration, since statins reduce cholesterol levels, they could interfere
with the formation of vitamin D and therefore cause vitamin D deficiency.
It is, however, interesting to
note that rosuvastatin increased vitamin D levels in
patients with vitamin D deficiency. On the other hand, another statin
fluvastatin did not produce a similar beneficial effect on vitamin D levels.
2. Do statins and vitamin
D have an additive beneficial effect on cardiovascular disease?
The beneficial effects of statins in
reducing atherosclerosis and
heart-related events are well known. Similar to statins, vitamin D also appears
to have an anti-atherogenic effect. There are several mechanisms that have been
suggested to be responsible for this benefit, which include the
triglyceride-lowering and the anti-inflammatory effects of vitamin D. Thus,
together with statins, vitamin D could possibly improve cardiovascular health.
3. Does vitamin D reduce the
side effects of statins?
Statins can cause
muscle-related side effects resulting in muscle aches, soreness and cramps. A
more serious form of muscle damage is called rhabdomyolysis, which is
characterized by breakdown of muscles. The breakdown products are excreted in
the urine, and can precipitate kidney failure.
Researchers have found
that deficiency of vitamin D has been associated with the development
of statin-induced myalgia. It has been suggested that vitamin D deficiency
results in a situation where more of an enzyme that is needed to breakdown
statins is used up for the activation of vitamin D. As a result, the statin
levels in the blood increase and cause the muscle-related adverse effects.
It is also interesting to
note that low vitamin D levels are independently associated with muscle pain.
Therefore, it may be necessary to treat patients with vitamin D deficiency with
supplements before taking statins to ensure that their vitamin D levels are
within the normal range.
4. Do statins complement the
action of vitamin D in improving bone density?
Statins appear to improve
vitamin D levels and bone density like vitamin D complements the effects of statins. Researchers
found a higher increase in bone marrow density in the lumbar spine, the femoral
neck and the forearm in patients taking statins. Possible mechanisms for an
increase in vitamin D levels are an increased synthesis of vitamin D or
prevention of breakdown. Statins may also increase the bone mineral density by
stimulating the proliferation and maturation of osteoblasts, the bone forming
cells thereby promoting the formation of new bone, or by inhibiting the
osteoclasts, the cells that resorb or eat up the bone.
Thus, initial reports
suggest that there exists a relationship between statins and vitamin D, though
these have yet to be proved through large and reliable studies. Till then, it would possibly be a good idea to
make sure that patients taking statins have normal vitamin D levels.
