Role of Vitamin D in preventing heart disease in children both HIV-positive and HIV-negative

Begins enrolling children and young adults, HIV and non-HIV, in studies

While Vitamin D is essential for proper bone health, a number of research studies have linked it to guarding against cardiovascular disease and certain cancers. It is unique among vitamins in that it is made by the body in response to sunlight but is naturally present in very few foods. Recent studies have confirmed that vitamin D deficiency is common, even in sunny states such as Florida.

People who are HIV-positive, of all ages and all races, may be at particularly high risk of having vitamin D deficiency, in part, because certain HIV medications appear to lower vitamin D levels.

University Hospitals (UH) Rainbow Babies & Children's Hospital will be looking at the role of Vitamin D in preventing heart disease in children and young adults who are both HIV-positive and HIV-negative. The studies are being led by Grace McComsey, M.D., Division Chief, Pediatric Infectious Diseases, Rheumatology & Global Child Health at UH Rainbow Babies & Children's Hospital and a Professor of Pediatrics at Case Western Reserve University School of Medicine.

"In HIV-positive populations now, we have made great strides in helping patients live productive lives with the help of medications," said Dr. McComsey. "However, we are finding that patients are experiencing higher rates of heart disease and cancer."

While children and young adults with HIV may not yet experience outward symptoms of heart disease at their age, ultrasounds are already revealing abnormal vessel thickness or plaques compared to healthy youth. These kids are at a significantly higher risk than the general population for heart disease. In adults with HIV, research has shown that the risk of heart disease rises by 26 percent for every year of treatment. For these kids who will likely be on HIV medications for decades, heart disease is an important risk.

"The large success we have had in helping them live longer through HIV medications is now threatened by an increase risk of heart disease," said Dr. McComsey.

Dr. McComsey said the increased risk is due at least in part, to heightened inflammation in these patients and that several studies had indicated that deficiency in Vitamin D may increase inflammation and heart disease risk.

In two new UH Rainbow Babies & Children's Hospital studies, a total of 240 HIV-positive and 240 HIV-negative patients will be studied to understand how Vitamin D deficiency affects inflammation, immune system and risk of heart disease. Also, participants with low vitamin D levels will be randomly assigned to one of three oral dose levels of monthly vitamin D to determine which dose may be the best for reducing heart disease, inflammation as well as boosting the immune system and bone density.

Heart and bone disease, inflammation and immune system function will be measured through biomarkers found in blood and urine samples, and through ultrasound tests that can reveal blockage in arteries and measure thickness of bone. The researchers will also look at the effect of HIV medications on accelerating vitamin D deficiency.

"Vitamin D may present a safe opportunity to reverse the increased cardiovascular disease risk and immune co-morbidities in the HIV population," said Dr. McComsey. "Optimizing Vitamin D concentrations early in the course of HIV infection could offer a simple and cost-effective approach to minimize the risk of HIV-related heart disease and preserve immune function."

In the non-HIV study, researchers are hoping to also find an optimal level of Vitamin D that will help decrease heart risk and inflammation. That is because, similar to the case in HIV, data is also surfacing in the general population linking low vitamin D in the blood to higher risk of heart disease and cancer, both thought to be possibly the result of high inflammation and/or altered immune status.