Mixed Results for Trials of Testosterone in Older Men
In older men with low testosterone, 1 year of testosterone treatment improved bone density and corrected anemia of both known and unknown causes, but also increased the volume of coronary artery plaque, according to results reported from the Testosterone Trials (T Trials). Testosterone treatment had no effect on memory or other cognitive function. The results were reported in two journals of the American Medical Association.
The T Trials were conducted at 12 sites across the country in 790 men age 65 and older with low levels of testosterone and symptoms to which low testosterone might contribute. The studies were funded primarily by NIA; NHLBI, NINDS and NICHD also contributed. Additional funding, and the study drug and placebo, were provided by AbbVie Pharmaceuticals.
“A number of older men have testosterone levels below those found in healthy younger men,” said NIA director Dr. Richard Hodes. “In most cases, these low levels are not due to diseases known to affect testosterone levels. Many of these men also have problems that could be related to low testosterone, including impaired cognition, anemia, cardiovascular disease, diminished sexual function, decreased mobility and fatigue. The T Trials were designed to determine if testosterone treatment might help alleviate these symptoms and conditions while monitoring for adverse effects.”
“The results on diverse outcomes indicate the potential trade-offs between benefits and risks of testosterone treatment in older men,” said Dr. Evan Hadley, director of NIA’s Division of Geriatrics and Clinical Gerontology. “However, clarifying the effects of testosterone on many major clinical outcomes such as cardiovascular events, fractures and disability will require longer, larger scale trials. The results also illustrate that decisions about testosterone treatment need to be individualized, taking into account each patient’s balance of risks for the various conditions that testosterone treatment could affect.”
Survival Rate Seen Improving For Extremely Preterm Infants
Very early preterm infants are more likely to survive than in previous years and the survivors are less likely to have neurological problems, according to an analysis of records from an NIH research network.
Researchers found that of the more than 4,000 infants born at 11 sites within the network from 2000 to 2011, survival rates increased from 30 percent to 36 percent. The proportion of survivors who did not have a neurological or developmental impairment increased from 16 percent to 20 percent. The authors theorize that these improvements are a result of advances in the care provided to expectant mothers and their newborns.
The study appeared in the New England Journal of Medicine.
“Our study provides important information for physicians and family members planning the care of these extremely fragile newborns,” said study author Dr. Rosemary Higgins, a program scientist at NICHD. The study was conducted by researchers in the NICHD-funded Neonatal Research Network.
Infants in the study were born between the 22nd and 24th week of pregnancy, far earlier than the 40 weeks generally expected for a pregnancy to reach term. Those born from 2008 to 2011 had the lowest death rate (64 percent). From 2004 to 2007, the death rate was 70 percent, unchanged from 2000 to 2003.
Higgins stressed that the results encompass trends for a large number of infants at multiple research sites, but they should not be used to predict the outcome for an individual child.
“Every individual is different, and no single source of information can precisely predict a baby’s chances of survival or disability,” she said. “But our study’s findings do provide important information that physicians and family members can consult to help determine treatment strategies.”
Providing care to infants born so early is often challenging. Physicians and family members can be reluctant to expose an infant to sometimes painful life-support procedures. Those offered active treatment may survive, but may have hearing loss, blindness, cerebral palsy and severe intellectual disability.
Experimental Malaria Vaccine Provides Protection Against Multiple Strains
An investigational malaria vaccine has protected a small number of healthy U.S. adults from infection with a malaria strain different from that contained in the vaccine, according to a study published Feb. 21 in the Proceedings of the National Academy of Sciences. NIAID sponsored and co-conducted the phase 1 clinical trial.
Malaria is transmitted to humans through the bite of infected mosquitoes, which inject immature malaria parasites called sporozoites into a person’s bloodstream. The parasites travel to the liver, where they mature, multiply and spread via the bloodstream throughout the body causing malaria symptoms including chills, fever, headache, nausea, sweating and fatigue.
According to the World Health Organization, 214 million people were infected with malaria globally in 2015 and 438,000 people died, mostly young African children. The species Plasmodium falciparum is the most common cause of malaria morbidity and mortality in Africa. In the United States, travel-related malaria is a concern for international tourists, aid workers and military personnel worldwide.
The PfSPZ vaccine used in this study was developed by Sanaria Inc., of Rockville. It contains weakened P. falciparum sporozoites that do not cause infection but are able to generate a protective immune response against live malaria infection. Earlier research at the Clinical Center with the vaccine found it to be safe, well-tolerated and protective for more than a year when tested in healthy U.S. adults against a single Africa-derived malaria strain matched to the PfSPZ vaccine.
“An effective malaria vaccine will need to protect people living in endemic areas against multiple strains of the mosquito-borne disease,” said NIAID director Dr. Anthony Fauci. “These new findings showing cross-protection with the PfSPZ vaccine suggest that it may be able to accomplish this goal.”