Testing Helps Catch HIV Early, But Aggressive Use Of Antiretroviral Drugs In Asymptomatic Patients Could Breed More Resistant HIV

One of the most widely advocated strategies for dealing with HIV/AIDS could double the number of multi-drug-resistant HIV cases in the population of men who have sex with men (MSM) in LA County over the next 10 years, cautions a new study. 

In the United States, LA County has the largest incident population of HIV positive individuals. 

The so-called "test and treat" policy - which calls for universal testing for HIV as well as treatment with antiretroviral drugs for even those at the earliest stages of the disease - is popular because it has been shown to decrease the number of new HIV cases and deaths due to AIDS. 

The problem, according to the study, is that such aggressive and widespread use of antiretroviral drugs would also rapidly and dramatically increase the prevalence of multiple-drug-resistant HIV (MDR). 

"We're not saying that testing everybody and treating everybody is bad. All we're saying is that you should proceed with caution and closely monitor the prevalence of multi-drug-resistant HIV as you scale up the test and treat model," said lead author Neeraj Sood, associate professor at the USC Schaeffer Center for Health Policy and Economics. 

Sood collaborated with Zachary Wagner, also of the USC Schaeffer Center; USC Ph.D. student Emmanuel Drabo; and Raffaele Vardavas and Amber Jaycocks of the RAND Corporation. Their study received advance online publication by Clinical Infectious Diseases. 

Sood and his colleagues studied the MSM population in LA County, which accounts for 82 percent of people living with HIV/AIDS countywide. They tracked how the disease was treated from 2000 to 2009 and how the virus responded. 

Using data from the Centers for Disease Control and their own data, the researchers then generated a model of how the disease would respond under a more aggressive "test and treat" policy over the next 10 years. 

The model showed the prevalence of MDR jumping from 4.79 percent to 9.06 percent by 2023. 

A more cautious approach, Sood suggested, would be simply to aggressively test for the disease but to avoid prescribing antiretroviral drugs to asymptomatic patients. The modeling shows that strategy still making significant gains against HIV/AIDS, without the increase in MDR HIV. 

"Prior studies show a dramatic reduction in risk-taking behavior by individuals once they know their HIV-positive status," Sood said.

Source:http://www.medicalnewstoday.com/releases/257854.php

For Smokers, Low Levels of Vitamin D May Lead to Cancer

New research appearing online today in Clinical Chemistry, the journal of AACC, shows that decreased levels of vitamin D may predispose smokers to developing tobacco-related cancer. This study illustrates that simple vitamin D blood tests and supplements have the potential to improve smokers' health.

In the U.S. alone, cigarette smoking accounts for more deaths annually than HIV, illegal drugs, alcohol, motor vehicle injuries, suicides, and murders combined. It is the primary causal factor for at least 30% of all cancer deaths, and can lead to multiple kinds of cancer, including bladder, cervical, esophageal, head and neck, kidney, liver, lung, pancreatic, and stomach, as well as myeloid leukemia. According to the Centers for Disease Control and Prevention, the healthcare expenditures and productivity losses due to smoking cost the economy approximately $193 billion per year.

In this paper, Afzal et al. measured plasma vitamin D levels in blood samples collected in 1981-1983 from 10,000 Danes from the general population. Researchers then followed the study participants for up to 28 years through the Danish Cancer Registry. Of the participants, 1,081 eventually developed a tobacco-related cancer. The authors determined that the median vitamin D concentration among these participants was only 14.8 ng/mL, versus the higher 16.4 ng/mL median concentration found for all participants together.

These results show for the first time that the risk of tobacco-related cancers as a group is associated with lower concentrations of vitamin D. The data also indicate that tobacco smoke chemicals may influence vitamin D metabolism and function, while vitamin D may conversely modify the carcinogenicity of tobacco smoke chemicals. If further research confirms this, it would be consistent with previous studies demonstrating the anti-tumorigenic effects of vitamin D derivatives, as well as the correlation of vitamin D deficiency with favorable cancer-forming conditions and increased susceptibility to tobacco smoke carcinogens. Interestingly, though, low vitamin D levels were not connected with risk of other cancer types.

"Our analyses show that the association between lower concentrations of plasma vitamin D and higher risk of cancer may be driven by tobacco-related cancer as a group, which has not been shown before," stated author Børge G. Nordestgaard, MD, DMSc, in the paper. "This is important for future studies investigating the association between plasma vitamin D and risk of cancer."

Vitamin D May Lower Blood Pressure in Blacks

By Nicholas Bakalar

African-Americans have significantly higher rates of hypertension, and lower blood levels of vitamin D, than the rest of the population. Now a randomized trial suggests that vitamin D supplements may help lower blood pressure.In the three-month study, researchers randomly assigned 250 black men and women to one of four groups: one received a placebo, and the others received 1,000, 2,000, or 4,000 international units of vitamin D daily. The results were published online in the journal Hypertension.The effect was modest. While systolic blood pressure in the placebo group increased by 1.7 millimeters of mercury, it was lowered in the supplement groups: a 0.66 mm Hg decrease for those taking 1,000 international units a day; a 3.4 decrease in the 2,000-a-day group; and an average 4.0 decrease for those taking 4,000 units daily. “This degree of blood pressure reduction, if confirmed in future studies, would be considered clinically significant,” said the lead author, Dr. John P. Forman.Dr. Forman, an assistant professor of medicine at Harvard, said that the study did not specifically examine why this happens, but he added that vitamin D plays a role in the hormone system that helps regulate blood pressure, and “the activity of this hormone system may be more important in blacks.”