BRIEFS | January 2014 HR

Research Roundup

Newer Vaccines Have Significantly Reduced Ear Infections Vaccine2

Otitis media—more commonly known as ear infection—is the leading cause of pediatric healthcare visits and the most frequent reason children are prescribed antibiotics or undergo surgery.

Researchers from the University of Texas Medical Branch (UTMB) at Galveston have discovered that, during recent years, several interventions have been introduced aiming to decrease the otitis media burden—and they’ve been successful.

The 11-year study, published online November 25 in the journal JAMA Pediatrics, examined the trends in otitis media-related healthcare use in the United States for the first 10 years that a new type of vaccine came into use. The researchers, led by Tasnee Chonmaitree, MD, looked at insurance claims data from a nationwide managed healthcare plan of 7.82 million children under age 6 visiting a healthcare provider for an ear infection or complication or surgical intervention related to ear infection. Data were taken from insurance claims between 2001 and 2011. The first pneumococcal conjugate vaccine was introduced in the United States in 2000.

The researchers found there was a downward trend in visits from 2004 to 2011, with a significant drop in children younger than 2 years that coincided with the advent of the 13-valent vaccine, or PCV-13, in 2010.

Chonmaitree, professor of pediatrics in the division of pediatric infectious diseases, noted that this is the first study to determine otitis media-related healthcare use trends since the marketing of PCV-13 in the United States.

During the previous decade, considerable medical progress had been made in otitis media prevention. Among the major interventions are conjugate vaccines against Streptococcus pneumoniae, a major pathogen of acute otitis media. In the United States, 7-valent pneumococcal conjugate vaccine, PCV-7, was licensed in 2000, and routine PCV-7 vaccination has been associated with a significant reduction in ear infections, as well as a decrease in tube insertion related to recurrent and chronic ear infections.

In March 2010, the PCV-13 was licensed for use among US children 6 weeks to 6 years old. It succeeded PCV-7 and expanded coverage by offering protection against six additional strains of the bacteria. Today, roughly 90% of children under age 2 receive the PCV-13 vaccine.

“Medical interventions in the past decade, especially with the introduction of new vaccines, have really reduced the burden of this common childhood disease,” said Chonmaitree.

How common? About 80% of children will have experienced one or more episodes of otitis media by their third birthday, and more than 40% will have had three or more episodes. 

In addition, 80% of visits resulted in an antibiotic prescription. Earlier this year, however, the American Academy of Pediatrics (AAP) updated their clinical practice guidelines to allow an observation option, without initial antibiotic treatment in children who do not have serious ear infections and are older than age 2, and in younger children with unilateral otitis media (infection in only one ear). 

Chonmaitree is a member of the committee that made the new AAP recommendations and said that overuse of antibiotics is a significant factor fueling antibiotic resistance.

“Otitis media has a high socioeconomic impact worldwide,” said Chonmaitree. “In the United States, an estimated $4 billion is spent every year on otitis media-related healthcare.”

Significant Improvement for Tinnitus Sufferers Using VNS-Tone Therapy

University of Texas Dallas researchers have demonstrated that treating tinnitus, or ringing in the ears, using vagus nerve stimulation (VNS)-tone therapy, is safe and brought significant improvement to some of the participants in a small clinical trial.

Sven Vanneste, PhD, and Michael Kilgard, PhD, of the School of Behavioral and Brain Sciences used a new method pairing VNS with auditory tones to alleviate the symptoms of chronic tinnitus. Their results were recently published in the journal Neuromodulation: Technology at the Neural Interface.

VNS has been approved by the Food and Drug Administration (FDA) for treating various illnesses, including depression and epilepsy. It involves sending a mild electric pulse through the vagus nerve, which relays information about the state of the body to the brain.

“The primary goal of the study was to evaluate safety of VNS-tone therapy in tinnitus patients,” Vanneste said. “VNS-tone therapy was expected to be safe because it requires less than 1% of the VNS approved by the FDA for the treatment of intractable epilepsy and depression. There were no significant adverse events in our study.”

The study, which took place in Antwerp, Belgium, involved implanting 10 tinnitus sufferers with a stimulation electrode directly on the vagus nerve. They received 2½ hours of daily treatment for 20 days. The participants had lived with tinnitus for at least a year prior to participating in the study, and showed no benefit from previous audiological, drug, or neuromodulation treatments. Electrical pulses were generated from an external device for this study, but future work could involve using internal generators, eliminating the need for clinical visits.

Half of the participants demonstrated large decreases in their tinnitus symptoms, with three of them showing a 44% reduction in the impact of tinnitus on their daily lives. Four people demonstrated clinically meaningful reductions in the perceived loudness of their tinnitus by 26 dB.

“In all, 4 of the 10 patients showed relevant decreases on tinnitus questionnaires and audiological measures,” Vanneste noted. “The observation that these improvements were stable for more than 2 months after the end of the one-month therapy is encouraging.”

According to Vanneste, more than 12 million Americans have tinnitus severe enough to seek medical attention, of which 2 million are so disabled that they cannot function normally. He said there has been no consistently effective treatment.

In addition, a larger study involving four different centers will soon begin in the United States.

Obesity Associated with Higher Risk of Hearing Loss in Women obese

New research from Brigham and Women’s Hospital (BWH), published online in The American Journal of Medicine, finds that a higher body mass index (BMI) and larger waist circumference in women are each associated with higher risk of hearing loss, while a higher level of physical activity is associated with lower risk of hearing loss.

“We often think of hearing loss as an inevitable part of the aging process, but these findings provide evidence that potentially modifiable risk factors, such as maintaining a healthy weight and staying physically active, may help in the prevention of hearing loss or delay its progression,” said Sharon Curhan, MD, ScM, lead author of the paper and a researcher in the Channing Division of Network Medicine at BWH.

Using data from 68,421 women in the Nurses’ Health Study II who were followed from 1989 to 2009, researchers analyzed information on BMI, waist circumference, physical activity, and self-reported hearing loss. The baseline and updated information was obtained through validated biennial questionnaires. The researchers found that women with a BMI of 30-34 had a relative risk for hearing loss that was 17% higher, and those with a BMI of 40 or more had a relative risk that was 25% higher when compared with those with a BMI of less than 25.

For women with a waist circumference 80-88 cm (31.5-35.5 in), the relative risk for hearing loss was 11% higher; with a waist circumference greater than 88 cm, the relative risk was 27% higher when compared with women with a waist circumference less than 71 cm (28 in).

Researchers also found that a higher level of physical activity was associated with lower risk. Compared with women who were the least physically active, women who were the most physically active had a 17% lower risk of hearing loss. Walking, which was the most common form of physical activity reported among these women, was associated with lower risk; walking 2 hours per week or more was associated with a 15% lower risk of hearing loss, compared with walking less than 1 hour per week.

This research was funded by grants DC010811 and CA50385 from the National Institutes of Health and from Vanderbilt University School of Medicine.

Original citation for this article: Research roundup. Hearing Review. 2014: January: 46-47.