Healthy arteries are like long balloons that expand and contract with blood pressure variations. They should not be rigid pipes that do not distend. The balloon-like quality of arteries is called distensibility, and it is measured by ultrasound. In addition, ultrasound measures abnormal growth (hypertrophy) of the main pumping chamber of the heart, the left ventricle.
Recently, Turkish researchers, led by Doctor Osman Kuloğlu and 10 colleagues, working under the supervision of Professor Murat Çaylı, all of the Adana Numune Training and Research Hospital in Turkey, measured both aortic distensibility and left ventricular hypertrophy together with 25(OH)D levels in 136 newly diagnosed diabetics. They also measured high sensitivity C reactive Protein (CRP), a measure of inflammation.
Kuloglu O, Gür M, Seker T, Kalkan GY, Kirim S, Sahin DY, Harbalioglu H, Türkoglu C, Acele A, Elbasan Z, Ozaltun B, Cayli M.Serum 25-hydroxyvitamin D level is associated with aortic distensibility and left ventricle hypertrophy in newly diagnosed type 2 diabetes mellitus. Diab Vasc Dis Res. 2013 Jun 10.
In this cross sectional study, they grouped vitamin D levels in two categories, a group with levels higher than 20 ng/ml and a group with levels lower than 20 ng/ml. They found that vitamin D levels were independently associated with ventricular hypertrophy (p = 0.001), aortic distensibility (p < 0.001) and high-sensitive C-reactive protein (p = 0.002), with the higher the vitamin D group all fairing better.
When they looked at continuous vitamin D levels and aortic distensibility (rather than comparing those below 20 ng/ml to those above 20 ng/ml), there was a strong linear correlation between vitamin D levels and distensibility. The higher the vitamin D level, the better the distensibility, with an R value of .57.
Here you can see the graph of the data:
The authors concluded:
“Our study showed that low vitamin D level is independently associated with aortic distensibility as well as left ventricle hypertrophy and inflammation in newly diagnosed diabetic patients. Low vitamin D level may play a role in pathogenesis of impaired elastic properties of aorta and left ventricle hypertrophy in diabetic patients.”
Diabetic patients suffer from many complications, including increased risk of cardiovascular disease. Any new means of prevention or treatment to lower the risk would be welcome. Further research should be able to show the extent of benefit in being sufficient in vitamin D. In the meantime, there’s no reason for diabetic patients not to be sufficient in vitamin D.