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Research Briefs November 2016
Doxazosin Versus Prazosin in PTSD
Prazosin, used to treat symptoms of post-traumatic stress disorder (PTSD), has some drawbacks, say clinicians from Xavier University and George Washington University. They performed a compare–contrast review and concluded that prazosin’s me-too version, doxazosin, may be a better choice for several reasons.
For one, prazosin’s short half-life (two to three hours) and duration of action (six to 10 hours) mean patients need multiple daytime doses. Patients also need to take varying doses, a complication that can make it more difficult for them to stick to the regimen. In addition, the beneficial effects wear off within three hours, which can lead to nightmares in the latter half of regular sleep.
In contrast, doxazosin offers distinct advantages. One of the major benefits is a long half-life (16 to 30 hours), meaning it can be taken much less often than prazosin—even once daily. That pared-down regimen can help with medication adherence.
Research has shown doxazosin is safe and effective in patients with PTSD. The authors cite, for instance, a case report about a combat veteran who took 4 mg daily for eight weeks and had improved sleep quality, suffered fewer and less intense trauma-related nightmares, and was able to function better in the daytime.
Studies, although small, have found doxazosin significantly improved PTSD symptoms. One 12-week study of 51 patients found a significant drop in nightmares. Approximately 25% of the patients experienced full remission. Those researchers also found sleep recuperation improved within the first four weeks of treatment with doxazosin.
While prazosin compares well on certain adverse effects, such as dizziness and headache, doxazosin scores better on drowsiness, palpitations, anxiety, depression, and hallucinations. It also has an improved absorption profile, reducing the risk of hypotension.
Source: Psychiatric Annals, September 2016
Global Polio Vaccine Switch a Success
Type-2 circulating vaccine-derived polioviruses (cVDPV2s) have caused hundreds of cases of paralytic poliomyelitis since 2006. The type-2 component of oral poliovirus (OPV) vaccine was therefore scheduled for global withdrawal, and a synchronized switch was planned: from trivalent oral poliovirus vaccine (tOPV) to bivalent oral poliovirus vaccine (bOPV).
The 155 countries and territories that use OPV in their immunization programs have reported that they had completely stopped using tOPV by May 2016. (All manufacturers of OPV ended production of tOPV before the switch.) All countries not already using inactivated polio vaccine (IPV) have committed to introducing it. As of August 2016, 173 of 194 World Health Organization countries had introduced IPV into their programs—despite a global shortage of IPV.
The global cooperation in stopping tOPV use has gone smoothly and is “unprecedented,” according to the Centers for Disease Control and Prevention (CDC). But while it’s a milestone in the effort to eradicate polio, vigilance is still needed: Any tOPV found in a vaccine storage refrigerator or freezer should be destroyed. All remaining type-2 polio-viruses, including type-2 wild poliovirus, VDPV2s, and the type-2 Sabin polioviruses used in tOPV and monovalent OPV type-2 (mOPV2) should be destroyed or appropriately contained in certified poliovirus-essential facilities.
If type-2 poliovirus outbreaks do occur, the United Nations Children’s Fund has a global stockpile of approximately 36 million doses of mOPV2, with 100 million more to become available soon. Hundreds of millions of doses stored in bulk form are also available for conversion, the CDC says.
Ultimately, we won’t know how well the process went until we know the number of polio cases caused by cVDPV2s that arise after the tOPV withdrawal, the CDC says, “with fewer cases indicating a greater success.” As of August 31, 2016, no new circulating VDPV outbreaks had been identified in 2016.
Source: Morbidity and Mortality Weekly Report, September 2016
New Program Offers Medication Therapy Management Services to PCPs
Primary care physicians (PCPs) often don’t have the time to manage the complex medication needs of patients with chronic conditions, and PCPs working in federally qualified health centers (FQHCs) who care for low-income, at-risk patients face “particularly large barriers,” according to the Agency for Healthcare Research and Quality (AHRQ). But that lack of time can contribute to low patient adherence to medication regimens.
While clinical pharmacists can help, they may not be available to FQHCs, PCP offices, and other primary care settings—so innovators in Ohio established a statewide consortium or “shared learning community” that provides the resources for FQHCs to offer pharmacist-led medication therapy management (MTM) services to patients with diabetes or hypertension. The collaborating organizations include the Ohio Association for Community Health Centers, the Health Services Advisory Group, and six Ohio-based colleges of pharmacy.
The program’s developers, Jennifer Rodis, PharmD, BCPS, FAPhA, Assistant Dean for Outreach and Engagement at the Ohio State University (OSU) College of Pharmacy, and Barbara Pryor, MS, RD, LD, Manager of the Chronic Disease Section in the Ohio Department of Health (ODH), reported on the consortium’s program and successes in AHRQ’s Health Care Innovations Exchange.
Program leaders meet with participating pharmacists to orient them; those pharmacists then introduce the program to clinicians and staff at their respective practice sites. Every month, they check in with program leaders from the ODH, the OSU College of Pharmacy, and Ohio Association of Community Health Centers to give status updates and get guidance and troubleshooting advice.
The consortium has markedly increased the number of FQHCs offering pharmacist-led MTM services, as well as boosting awareness and interest in MTM. When the program began in 2013, very few of the 41 FQCHs in Ohio had pharmacist-led MTM programs, the AHRQ report says. Nine FQHCs now participate in the consortium.
During the first year, the three participating sites enrolled nearly 400 eligible patients with out-of-control hypertension or diabetes. By the end of that year, 68% of the hypertensive patients had controlled their blood pressure, and 45% of patients with diabetes were controlling their hemoglobin A1c. The pharmacists providing MTM addressed 75 adverse drug events and remedied 145 potential events.
Source: AHRQ, September 2016
Nurses’ Health Study Points to Risk Factors, Biomarkers for Some Cancers
Certain lifestyle, dietary, environmental, serological, and genetic factors may raise the risk of non-Hodgkin’s lymphoma (NHL), according to researchers who reviewed 40 years of follow-up data from the Nurses’ Health Study (NHS).
The researchers from Brigham and Women’s Hospital, Harvard University, and Boston University aimed to highlight the NHS’s contributions to epidemiologic knowledge of endometrial, ovarian, pancreatic, and hematological cancers. Among other things, they focused on findings that identified novel risk factors and markers of early detection, or helped clarify discrepant literature.
Because severe immune compromise is the “strongest, best-established risk factor” for NHL, the researchers say, they studied factors that might lead to subclinical immune dysregulation, such as diet, body mass index (BMI), and supplement use. They found a number of risk factors and biomarkers for NHL and the more than 35 distinct tumors in that category, including chronic lymphocytic leukemia (CLL). Trans fats and red meat, for instance, doubled the risk of NHL. The researchers also found a higher risk for women who reported long-term multivitamin use. However, they found no risk associated with diet or sugar-sweetened soda or aspartame, or with dietary intake of vitamin D.
Greater adiposity during childhood and adolescence was significantly associated with NHL. The researchers also observed a 19% increased risk of all NHL per 5-kg/m2 increase in BMI in young adulthood. Interestingly, taller women also had a higher risk of NHL.
The researchers conducted one of the first prospective studies to evaluate a putative inverse association of NHL risk with exposure to ambient ultraviolet radiation. They found, “contrary to expectation,” a 10% to 20% increased risk of NHL among women with the highest (versus lowest) ultraviolet-B exposure at baseline and birth, 5 years, and 30 years.
In investigating biomarkers, the researchers noted a “suggestive increase” in CLL risk associated with an Epstein-Barr virus antibody profile indicative of poor host immune control of the virus.
The researchers have established several working groups to study cancers such as NHL and multiple myeloma. They are also collecting archival tissue specimens for NHL, multiple myeloma, and Hodgkin’s lymphoma for better evaluation of factors related to the unique molecular subsets of hematological tumors.
Source: American Journal of Public Health, September 2016
Predicting Flu Epidemics
It’s easy to see there might be a seasonal link between “epidemic waves” of respiratory syncytial virus (RSV) infections and influenza. But forecasting seasonal patterns with accuracy isn’t so easy, due to the many varieties of flu and environmental factors.
Researchers from the Public Health Center of Valencia and University of Valencia in Spain say they have a way to predict an influenza epidemic three to four weeks in advance. And that could allow for more effective vaccination programs and influenza prophylaxis.
They used two epidemiologic surveillance systems: One (AVE), in use in Eastern Spain since 2004, collects real-time data from notifiable disease outbreaks and alerts. The second, RedMIVA, collects cases of RSV.
The researchers conducted a study that lasted from week 40 of 2010 to week 8 of 2014. During that time, 239,321 people reported cases of flu, and 19,676 cases of RSV were recorded, with 5,112 laboratory confirmed. Most (85%) of the RSV cases were children 1 year of age and younger.
Using the data from the surveillance systems, the researchers found that the peak of maximum activity of the influenza virus appears at least three weeks after the RSV peak.
They also found evidence suggesting that RSV infection has a short-term protective effect against type A (H1N1) influenza infection. The seasons with the highest number of recorded cases of RSV coincided with the lowest number of influenza cases. In both seasons, the predominant influenza virus was type A (H1N1).
Source: Epidemiology and Infection, September 2016