Effect of Vitamin D Supplementation on Exercise Adaptations in Patients on Statin Therapy
Status:
Completed
Trial end date:
2015-12-01
Target enrollment:
Participant gender:
Summary
Statins along with lifestyle modifications including exercise are commonly prescribed to
patients with type 2 diabetes. American diabetes association recommends using
moderate-intensity statin and lifestyle therapy for patients with diabetes aged ≥40 years,
even without additional cardiovascular disease(CVD) risk factors.. Myopathy is a well known
adverse effect of statins, which occurs in 1-7% of patients. The spectrum of statin-related
myopathy ranges from common benign myalgia to rare but life threatening rhabdomyolysis. Being
lipophilic, simvastatin diffuses nonselectively into extrahepatic tissues such as muscle,
leading to higher incidence of myopathy among statin users.
In addition, simvastatin attenuates the exercise-induced increase in cardiorespiratory
fitness, and reduces the skeletal muscle mitochondrial content and oxidative capacity in
humans. Impaired cardiorespiratory fitness and mitochondrial function is possibly due to
reduction in Coenzyme Q10, which is a component of the electron transport chain and is
indispensable for generation of adenosine triphosphate (ATP) during oxidative phosphorylation
in mitochondria. Statins or hydroxyl-methylglutaryl coenzyme A (HMA CoA) reductase inhibitors
interfere with the production of mevalonic acid, which is a precursor in the synthesis of
coenzyme Q10.
Mitochondrial dysfunction has also been reported in vitamin D deficient individuals which has
been attributed to intra-mitochondrial calcium deficiency or deficient enzyme function of the
oxidative pathway ( by direct effect of vitamin D on enzyme gene or protein expression).
Thus, vitamin D may improve the statin-mediated changes in cardiorespiratory fitness and
mitochondrial function by improving the enzymatic machinery involved in oxidative
phosphorylation which is blocked by statin. This study is being done to look for the effect
of vitamin D supplementation on simvastatin-mediated change in exercise-mediated
cardiorespiratory fitness and skeletal muscle mitochondrial content in adults with type 2
diabetes
Phase:
Phase 3
Details
Lead Sponsor:
Postgraduate Institute of Medical Education and Research
Treatments:
Cholecalciferol Ergocalciferols Hydroxymethylglutaryl-CoA Reductase Inhibitors Simvastatin Vitamin D Vitamins