Vitamin D deficiency is associated with
“silent” coronary artery disease, according to the results of a study involving
HIV-positive African Americans published in the online edition of Clinical Infectious Diseases. Other risk
factors included high blood pressure, long-term cocaine use and antiretroviral
“The study found that among cardiovascularly
asymptomatic African Americans with HIV infection, vitamin D deficiency was
independently associated with a greater than two-fold increase in the risk of
the presence of significant coronary stenosis [narrowing of the blood
vessels],” comment the authors.
African Americans have a high prevalence of
coronary artery disease. The exact causes are uncertain and traditional risk
factors do not appear to account for all this increased risk.
It is therefore significant that a number
of recent studies have suggested a relationship between vitamin D deficiency
and an increased risk of coronary artery disease.
Vitamin D deficiency is highly prevalent in
African Americans. As HIV-positive African Americans have an especially
increased risk of coronary disease, investigators from Johns Hopkins University
designed a study to assess a possible relationship between this illness and
vitamin D deficiency.
A total of 674 HIV-positive African
Americans adults were recruited to the study, which ran between 2003 and 2011.
None had diagnosed coronary artery disease.
The patients had a blood test to monitor
their vitamin D levels, and CT scans were performed to measure coronary stenosis.
Most of the patients (64%) were men and
their median age was 46 years. The median vitamin D level was 17.0 ng/dl. The
prevalence of vitamin D deficiency (below 10ng/dl) was 20%. The vast majority
of patients were assessed as having a low ten-year risk of cardiovascular
The CT scans revealed that 10% of patients
had significant coronary stenosis. “This rate is high, considering that almost
90% of the population was at a low risk based on Framingham risk score,”
comment the authors.
Prevalence of coronary stenosis among
patients who had used HIV therapy for less than six months was 6%. It was 11%
among those who had used HIV therapy for over six months. Prevalence of silent
coronary artery disease among patients who had been taking antiretroviral
therapy for over six months and who had vitamin D deficiency was 16%.
The prevalence of coronary stenosis also
differed according to cocaine use. It was 8% among those who had never used the
drug or had taken it for less than 15 years. Prevalence was 13% among longer-term
cocaine users, and was 19% among patients with 15 years or more of cocaine use
and vitamin D deficiency.
Overall 8% of patients who were not vitamin
D deficient had narrowing of the coronary artery compared to 15% of those who
had vitamin D deficiency.
The single most important risk factor for
coronary stenosis was vitamin D deficiency, which more than doubled the risk of
this manifestation of silent cardiovascular disease (aOR = 2.28; 95% CI,
1.23-4.21). The next most important risk factor was HIV therapy lasting over
six months (aOR = 2.26; 95% CI, 1.17-4.36).
“Our findings suggest that vitamin D
deficiency is independently associated with the presence of significant
coronary stenosis,” write the authors. “To our knowledge, this is the first
study to examine whether vitamin D deficiency is associated with silent
coronary artery disease in cardiovascularly asymptomatic African American
adults with HIV infection.”
A number of traditional risk factors were
also significant. These included male gender (aOR = 2.19; 95% CI, 1.17-4.10),
diastolic blood pressure above 85 mmHg (aOR = 1.94; 95% CI, 1.02-3.68), LDL-cholesterol
above 100 mg/dl (aOR = 1.95; 95% CI, 1.13-3.36) and cocaine use for over 15
years (aOR = 1.77; 95% CI, 1.01-3.10).
“Our results further underscore the need
for aggressive interventions directed towards these important risk factors,”
comment the investigators.
They conclude, “as compared with
identifying and successfully managing some traditional risk factors for coronary
artery disease, including cigarette smoking cessation, and maintaining optimal
blood pressure control, vitamin D deficiency may be much easier to screen for