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Individual Antiretrovirals Not Tied to Vitamin D Deficiency in London HIV Clinic - (average age 48, 50% vit D low/deficient, 40% osteopenia, 13% oseoporosis)
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XVIII International AIDS Conference, July 18-23, 2010, Vienna
Mark Mascolini
from Jules: there were a number of vitamin D studies presented at IAC, which are being reported on by NATAP. All of these studies found a high prevalence of vitamin D deficiency & severe deficiency, some reported on the percent of patients with osteopenia & osteoporosis and the percentages were high, and the average age in these studies is about 45 years old. It is misleading when some researchers say the percent of HIV+ individuals with deficient vitamin D levels is similar to the general population because HIV+ individuals are also experienced accelerated aging, early frailty, cognitive impairment, are taking concurrently often ARTs that appear to be associated with bone loss or reduced vitamin D levels, although 2 studies a t IAC found protease inhibitor use was not associated with low vitamin D levels. So, due to all these conditions HIV+ individuals are also experiencing (frailty, accelerated aging, neuropathy, mitochondrial loss, muscle wasting/insufficiency) this puts patients aging at greater risk for fractures. A study here from the VA in Southwestern Texas by Bedimo finds fractures associated with mortality in HIV+, but in the general population mortality has been associated with fractures, but I think this VA study is the first to report mortality & fractures associated in HIV. In addition, we do not know if vitamin D supplementation has a benefit in HIV or which regimen of supplementation might have benefit. Anecdotal reports are that standard vitamin D supplementation does not increase vitamin D levels in a sustained way, we don't know the safety of high does vitamin D supplementation (20,000 or 50,000 given ongoing or episodically, these questions must be studied. I fear & suspect increased mortality will start to emerge in patient populat ions as they start entering their 60s in larger numbers in the near future. NIH research commitment is sorely lacking regarding serious questions related to aging, bone, neurologic impairment, the question of whether HIV or immunosenescence accelerates aging in HIV+ individuals.
Unlike some previous analyses, a cross-sectional study from London's Chelsea and Westminster Hospital HIV clinic found no correlation between use of individual antiretrovirals and vitamin D deficiency [1]. Another study also presented at the International AIDS Conference linked efavirenz use to vitamin D deficiency in US Women's Interagency HIV Study (WIHS) participants [2], and previous work found an association between tenofovir and low D levels [3].
The Chelsea and Westminster study involved 312 consecutive patients seen in July 2009 at the HIV clinic, 274 of them (88%) men. The group had a median age of 48 years (range 25 to 83) and had been infected with HIV for a median of 12 years (range 0 to 26). Everyone studied was taking combination antiretroviral therapy. The investigators defined a normal vitamin D level as 25(OH)D above 70 nmol/L, low as 40 to 70 nmol/L, and deficient as below 40 nmol/L. (To convert to ng/mL, divide by 2.5.)
Median vitamin D concentration stood at 66 nmol/L (26.4 ng/mL) and ranged from below 10 to 221 nmol/L. While 109 people (35%) met the study definition of low D levels, 64 (21%) were rated deficient.
Univariate analysis identified only two factors related to vitamin D levels, gender and race. Average levels in women were 49.1 nmol/L, compared with 78 nmol/L in men (P < 0.001). D concentrations averaged 77.4 nmol/L in whites, 37.6 nmol/L in black Africans, and 58.3 nmol/L in others (P < 0.001).
CD4 count, viral load, hepatitis status, and alkaline phosphatase level did not affect vitamin D readings in the univariate analysis. Nor did use of any of the antiretrovirals studied, including any protease inhibitor, abacavir, didanosine, emtricitabine, lamivudine, tenofovir, zidovudine, efavirenz, etravirine, nevirapine, maraviroc, raltegravir, and enfuvirtide,
Clinic records showed that 103 people (33%) had bone scans in the last 6 months for reasons unrelated to this study. The scans showed that 49 people had normal bone mineral density, 40 had osteopenia, and 14 had osteoporosis. Vitamin D levels averaged 70.5 nmol/L in people with normal bone density, 71.7 nmol/L in those with osteopenia, and 58.2 nmol/L in those with osteoporosis, and these differences were not statistically significant (P = 0.638).
The Chelsea and Westminster team argued that "lack of association of low vitamin D levels with alkaline phosphatase level and bone mineral density findings call into question the study of these tests as part of routine HIV care." But because some research links low vitamin D to HIV disease progression [4], the investigators concluded that "optimization of the vitamin D level is essential in individuals living with HIV, in particular, women and those from ethnic minorities."
References
1 Rashid T, Devitt E, Mandalia S, et al. No association of vitamin D levels with individual antiretroviral agents, duration of HIV-infection, alkaline phosphatase levels nor bone mineral density findings. XVIII International AIDS Conference. July 18-23, 2010. Vienna. Abstract WEPDB105.
2 Adeyemi OM, Agniel D, French A, et al. High rates of vitamin D deficiency among HIV-infected at at-risk women in the United States. XVIII International AIDS Conference. July 18-23, 2010. Vienna. Abstract WEPDB101.
3. Wanner DP, Tyndall A, Walker UA. Tenofovir-induced osteomalacia. Clin Exp Rheumatol. 2009;27:1001-1003.
4. Villamor E. A potential role for vitamin D on HIV infection. Nutr Rev. 2006;64(5 Pt 1):226-233.
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