We see many people who complain that they are losing hearing but their usual audiometric tests are normal. In most of these cases, it is felt that they are experiencing an age-related decrease in central auditory processing, which makes it more difficult to understand speech in the presence of background noise,. A recent study from Dr Gates at the University of Washington and described in US News & World Report may shed some light on this problem:
Memory Problems Tied to Sound Processing Disorder
Inability to filter out background noise may be indicator of mild impairment, study says
Posted July 22, 2008
TUESDAY, July 22 (HealthDay News) -- Mild memory impairment may be associated with a sound processing disorder called central auditory processing dysfunction, say U.S. researchers.
People with the disorder have difficulty hearing in complex situations with competing noise, such as making out what one person is saying while many people in a group are talking at the same time.
"Central auditory processing dysfunction is a general term that is applied to persons whose hearing in quiet settings is normal or near normal yet who have substantial hearing difficulty in the presence of auditory stressors such as competing noise and other difficult listening situations," according to background information in the study. "Central auditory testing is important in evaluating individuals with hearing difficulty, because poor central auditory ability, per se, is not helped by amplification and requires alternative rehabilitation strategies."
Previous research has found that people with Alzheimer's disease and other types of dementia have central auditory processing dysfunction.
This new study by Dr. George A. Gates, of the University of Washington, Seattle, and colleagues included 313 people, average age 80, taking part in a dementia surveillance program that began in 1994. Of the participants, 17 had been diagnosed with dementia, 64 had mild memory impairment, and 232 had no memory problems.
Three tests were used to assess the participants' central auditory processing. In one test, nonsense sentences were read over the background of an interesting narrative. In the other two tests, separate sentences or numbers were read into each ear simultaneously.
"These central auditory processing test paradigms evaluate how well an individual manages competing signals, a task that requires adequate short-term memory and the ability to shift attention rapidly," the researchers noted.
Participants with dementia and mild memory impairment scored significantly lower on the tests than those without memory problems. The findings were published in the July issue of the Archives of Otolaryngology -- Head & Neck Surgery.
"Central auditory function was affected by even mild memory impairment," the researchers wrote. "We recommend that central auditory testing be considered in the evaluation of older persons with hearing complaints as part of a comprehensive, individualized program to assist their needs in both the aural rehabilitative and the cognitive domains."
http://health.usnews.com/articles/health/healthday/2008/07/22/memory-problems-tied-to-sound-processing-disorder.html
Friday, July 25, 2008
Tuesday, July 8, 2008
HPV and Head and Neck Cancer Survival
Researchers at the University of Michigan Comprehensive Cancer Center have found a series of markers that indicate which patients are more likely to survive cancers of the base of the tongue and tonsils (Journal of Clinical Oncology, July 1, 2008).
Most notably, they found that cancers linked to HPV, or human papillomavirus, are the most responsive to current chemotherapy and radiation treatments, while tumors that express high levels of a certain growth factor receptor are the least responsive and most deadly.
The researchers call these and other markers a promising step in the direction of tailored, individualized treatment for a type of cancer that can have dramatic impact on essential abilities such as swallowing and speaking.
"The chemotherapy and radiation therapy we use to treat this type of cancer is very aggressive. If we can identify those patients most likely to respond, we could reduce the intensity of the therapy for those likely to have the best outcomes," stated Thomas Carey, PhD, professor and distinguished research scientist at the U-M Kresge Hearing Research Institute and co-director of the head and neck oncology program at the U-M Comprehensive Cancer Center. "At the same time, we hope to identify new treatments that specifically target those tumors that we know are not responding to current therapies." Dr. Carey was the senior author on both papers.
Cancers of the tonsils and the base of the tongue have increased in recent years, in what Dr. Carey calls an "epidemic" of HPV-induced head and neck cancer. This has occurred at the same time that declines in smoking rates have led to a decrease in the incidence of other types of head and neck cancers. HPV is the virus that can cause cervical cancer and is the target of a new vaccine.
"The biggest challenge is how best to treat patients with tumors that stem from tobacco and alcohol use as opposed to tumors linked to HPV. We now know they're two different cancers," said study author Francis Worden, MD, assistant professor of internal medicine at the U-M Medical School.
In this study, researchers treated 66 patients with advanced oropharyngeal cancer, which includes cancer of the tonsils and the base of the tongue. Study participants were given an initial course of chemotherapy to gauge the tumor's response. Those whose tumor was reduced by more than half of its original size received a full course of chemotherapy and radiation given simultaneously. Patients whose tumors did not respond were referred for surgery.
Fifty-four of the 66 participants responded to the initial chemotherapy. Of that group, 62 percent are alive today without evidence of cancer, and 73 percent fully preserved their organs.
Participants whose cancer did not respond to the chemotherapy and radiation went on to receive surgery. The researchers found that even with surgery, only 4 of 11 patients survived.
"For most patients, the chemoradiation was very effective. But a subset of patients still do not do well. Our next step was to look at the biomarkers to see if we could determine which patients were responding to treatment, based on the tumor biology," said Dr. Carey, who is also associate chair and professor of otolaryngology and pharmacology at the U-M Medical School.
By looking biopsies taken before treatment, the researchers found 64 percent of the tumors were positive for high-risk strains of HPV. Almost all of the HPV-positive tumors responded to initial chemotherapy and 78 percent of those patients survived with their organs preserved. Of the HPV-negative study participants, only four of 15 survived. In addition, the researchers found that patients whose tumor expressed a marker called EGFR had worse outcomes.
"The combination of markers was an important indicator. Patients whose tumors expressed high levels of EGFR did poorly. But those who had high EGFR and were also HPV-positive had some protection. Patients with high EGFR and low HPV fared the worst. This is a step in the direction of affecting future treatment," said Bhavna Kumar, a research laboratory specialist who was the lead study author.
The researchers also found that tumors with low expression of a protein called p53, combined with high expression of another protein, BCLXL, also had poor outcomes. These markers provide additional targets for potential new therapies.
About 35,300 Americans will be diagnosed with head and neck cancer this year, according to the American Cancer Society.
Additional study authors were Julia S. Lee, Gregory T. Wolf, Kitrina G. Cordell, Jeremy M.G. Taylor, Susan G. Urba, Avraham Eisbruch, Theodoros N. Teknos, Douglas B. Chepeha, Mark E. Prince, Christina I. Tsien, Nisha J. D'Silva, Carol R. Bradford, Huong H. Tran, Kun Yang, David M. Kurnit, Joshua A. Bauer, Nancy Wallace, Tamara Miller, and Heidi Mason.
http://speech-language-pathology-audiology.advanceweb.com/editorial/content/editorial.aspx?cc=117403
Most notably, they found that cancers linked to HPV, or human papillomavirus, are the most responsive to current chemotherapy and radiation treatments, while tumors that express high levels of a certain growth factor receptor are the least responsive and most deadly.
The researchers call these and other markers a promising step in the direction of tailored, individualized treatment for a type of cancer that can have dramatic impact on essential abilities such as swallowing and speaking.
"The chemotherapy and radiation therapy we use to treat this type of cancer is very aggressive. If we can identify those patients most likely to respond, we could reduce the intensity of the therapy for those likely to have the best outcomes," stated Thomas Carey, PhD, professor and distinguished research scientist at the U-M Kresge Hearing Research Institute and co-director of the head and neck oncology program at the U-M Comprehensive Cancer Center. "At the same time, we hope to identify new treatments that specifically target those tumors that we know are not responding to current therapies." Dr. Carey was the senior author on both papers.
Cancers of the tonsils and the base of the tongue have increased in recent years, in what Dr. Carey calls an "epidemic" of HPV-induced head and neck cancer. This has occurred at the same time that declines in smoking rates have led to a decrease in the incidence of other types of head and neck cancers. HPV is the virus that can cause cervical cancer and is the target of a new vaccine.
"The biggest challenge is how best to treat patients with tumors that stem from tobacco and alcohol use as opposed to tumors linked to HPV. We now know they're two different cancers," said study author Francis Worden, MD, assistant professor of internal medicine at the U-M Medical School.
In this study, researchers treated 66 patients with advanced oropharyngeal cancer, which includes cancer of the tonsils and the base of the tongue. Study participants were given an initial course of chemotherapy to gauge the tumor's response. Those whose tumor was reduced by more than half of its original size received a full course of chemotherapy and radiation given simultaneously. Patients whose tumors did not respond were referred for surgery.
Fifty-four of the 66 participants responded to the initial chemotherapy. Of that group, 62 percent are alive today without evidence of cancer, and 73 percent fully preserved their organs.
Participants whose cancer did not respond to the chemotherapy and radiation went on to receive surgery. The researchers found that even with surgery, only 4 of 11 patients survived.
"For most patients, the chemoradiation was very effective. But a subset of patients still do not do well. Our next step was to look at the biomarkers to see if we could determine which patients were responding to treatment, based on the tumor biology," said Dr. Carey, who is also associate chair and professor of otolaryngology and pharmacology at the U-M Medical School.
By looking biopsies taken before treatment, the researchers found 64 percent of the tumors were positive for high-risk strains of HPV. Almost all of the HPV-positive tumors responded to initial chemotherapy and 78 percent of those patients survived with their organs preserved. Of the HPV-negative study participants, only four of 15 survived. In addition, the researchers found that patients whose tumor expressed a marker called EGFR had worse outcomes.
"The combination of markers was an important indicator. Patients whose tumors expressed high levels of EGFR did poorly. But those who had high EGFR and were also HPV-positive had some protection. Patients with high EGFR and low HPV fared the worst. This is a step in the direction of affecting future treatment," said Bhavna Kumar, a research laboratory specialist who was the lead study author.
The researchers also found that tumors with low expression of a protein called p53, combined with high expression of another protein, BCLXL, also had poor outcomes. These markers provide additional targets for potential new therapies.
About 35,300 Americans will be diagnosed with head and neck cancer this year, according to the American Cancer Society.
Additional study authors were Julia S. Lee, Gregory T. Wolf, Kitrina G. Cordell, Jeremy M.G. Taylor, Susan G. Urba, Avraham Eisbruch, Theodoros N. Teknos, Douglas B. Chepeha, Mark E. Prince, Christina I. Tsien, Nisha J. D'Silva, Carol R. Bradford, Huong H. Tran, Kun Yang, David M. Kurnit, Joshua A. Bauer, Nancy Wallace, Tamara Miller, and Heidi Mason.
http://speech-language-pathology-audiology.advanceweb.com/editorial/content/editorial.aspx?cc=117403
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