Evidence-Based Medicine This department uses the best available scientific findings to offer practice guidance on a wide range of conditions seen in primary care.The author, Alan Ehrlich, MD, is a deputy editor for DynaMed, Ipswich, Mass., and assistant clinical professor in Family Medicine, University of Massachusetts Medical School in Worcester. DynaMed (www.ebscohost.com/dynamed/) is a database that provides evidence-based infor- mation on more than 3,000 clinical topics and is updated daily through systematic surveillance covering more than 500 journals.The most important evidence identified is summarized here.
MULTIVITAMIN PLUS SELENIUM SUPPLEMENT MAY SLOW P ROGRESSION OF HIV IN TREATMENT-NAÏVE ADULTS IN LOW-RESOURCE SETTINGS Level 2: Mid-level evidence Micronutrient deficiencies are common in patients with HIV infection and may occur very early in the course of the disease, affecting immune function and disease progression. In low-resource settings where availability of antiretroviral therapy can be limited, other interventions to slow disease progression may be particularly valuable. Previous studies have suggested that micronutrient supplements may improve HIV markers in patients with advanced disease. A recent randomized trial in Botswana evaluated the effects of supplementation in 878 treatment-naïve adults with early, asymptomatic HIV infection ( JAMA. 2013;310:2154-2163). Patients with HIV infection subtype C were randomized to one of four daily treatments for two years: multivitamins plus selenium (in one tablet) vs. multivitamin only vs. selenium only vs. placebo. Vitamins included thiamin 20 mg, riboflavin 20 mg, niacin 100 mg, vitamin B6 25 mg, vitamin B12 50 mcg, folic acid 800 µg, vitamin C 500 mg, and vitamin E 30 mg. The selenium dose was 200 µg. All patients had a CD4 count >350/µL and no history of AIDSdefining conditions at baseline. The primary outcome was disease progression defined as CD4 count ≤250/µL, and the secondary outcome was a composite of disease progression, development of AIDS-defining conditions, and AIDS-related death. A total of 24.9% of patients were lost to followup or dropped out of the trial (with 7.5% discontinuing due to pregnancy). The incidence
Micronutrient supplements may be an inexpensive way to improve treatment for HIV patients in low-resource settings.
of the composite outcome (progression plus AIDS outcomes) was significantly reduced in the multivitamin plus selenium group (6.48 per 100 person-years) compared with placebo (10.95 per 100 person-years, p=0.04). Incidence in the other two groups was not significantly different from placebo. For the primary outcome of disease progression, incidence in both the multivitamin-plus-selenium group and the multivitamin-only group were significantly reduced compared with placebo. The rates of adverse events were similar among groups, and there were no significant differences in HIV viral load among groups. These results suggest an inexpensive way to improve treatment for HIV patients early in the course of the disease in low-resource settings. It remains to be seen whether the benefits would also be found in parts of the world where most patients have access to a diet that is more likely to supply all of the essential nutrients.
CLARITHROMYCIN MIGHT INCREASE ALL-CAUSE MORTALITY AND HOSPITALIZATION FOR ACUTE KIDNEY INJURY COMPARED WITH AZITHROMYCIN IN OLDER ADULTS RECEIVING CALCIUM CHANNEL BLOCKERS Level 2: Mid-level evidence Calcium channel blockers (CCBs) are metabolized by the cytochrome P450 3A4 (CYP3A4) enzyme. The macrolide antibiotic clarithromycin The quality of the evidence supporting each item is rated from Level 1 (highest) to Level 3 (lowest). Absolute risk reductions are presented as the number needed to treat (NNT) for one patient to benefit. Absolute risk increases are presented as the number needed to harm (NNH).
96 THE CLINICAL ADVISOR • FEBRUARY 2014 • www.ClinicalAdvisor.com
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