It Begins...

So for the last 6 years or so, I have struggled with an unidentified infection which runs on a cycle. At first, it was a 3-4 week cycle and included very significant strep-like symptoms. In 2008, I underwent a tonsillectomy which was supposed to 'fix' me. It did for 6 weeks, but then my infection returned on a 6-week cycle. The symptoms weren't always as bad, and if I slept 10 hours a night for several nights prior to the infection, I could delay it a day or two and speed up my recovery but they were always inevitable. My third (or fourth?) otolaryngologist decided to go ahead and take my adenoids, which had somehow been left by my first otolaryngologist. I'm not surprised. I saw him once and couldn't pick him out of a lineup. It was an assembly-line tonsillectomy. The adenoidectomy made for an awful recovery but I made it, and this time my infections weren't even delayed. They still happen every 6 weeks, almost to the day. My last infection ran from May 23 through May 31 and it looks like Day 1 is here since I popped a 99.6-degree fever over lunch.

I found it important to share because it explains why I will probably take tomorrow off and spend it sleeping/reading/updating.

Now, the much-anticipated summary of several of my articles so far...

1. Estimated Leisure-Time Noise Exposure, Hearing Thresholds, and Hearing Symptoms of Finnish Conscripts. Lt Col (Med) Toivonen. Military Medicine (2005)
This article didn't provide a whole lot of useful information aside from a formula for weighted weekly and lifetime exposure to noise. Over 1000 young adults were in the study (obligatory military service) and the most frequent activities were, "watching television, listening to a home stereo, and going to night clubs and pubs." In addition, "The conscripts considered festivals and concerts, shooting firearms, playing in a band, and using tools indoors and outdoors to be the 'loudest' leisure-time activities." What's unfortunate about this is that those activities are more frequently outdoors and done on a more short-term basis as opposed to home stereo systems and television sets which are more frequently indoors and still set to a relatively high level.
Another scary statistic is that, "When the group with actual hearing loss was compared with the self-reported hearing loss, 79% of the conscripts with hearing loss did not know or disclaimed their hearing loss, and only 18% knew their hearing was not normal." For this study, 'loss' was defined as beginning at thresholds elevated at least 20dBHL.
One other thing I felt worth mentioning was that the author stated, "On a whole, the young adults were more active in several noisy activities and used more hours during the week in noise activities than the adults did." As the other articles have pointed out, young ears are less fragile than 'old' ears, so if the young ears are those exposed to this extra noise, then it shouldn't affect them much. But where does it end? At what point do we say, "That's just wanton disrespect for your ears"?


2. Can a hearing education campaign for adolescents change their music listening behavior? Viktor Weichbold and Patrick Zorowka. Int'l Journal of Audiology (2007)
This article, another foreign one based in Austria, was aimed at educating young adults. The subjects were those who attend discotheques, rock concerts, noisy pubs/parties, and those who listen to loud music or play in a band. They held classes for the students, "...four 45-minute sessions spread over three days and includ[ing] a variety of didactic approaches to make the topic of hearing conservation as attractive as possible: multimedia presentations... demonstrations of ear protection devices and hearing aids, role-play, questionnaire survey, creative group work... and a discussion with a hearing-impaired person or tinnitus sufferer."
The program offered Regeneration Breaks as an option instead of dampening ear protection... just taking a break and sitting in a quiet area before returning to the noise. Those breaks seemed to be much more popular than wearing earplugs. After the campaign, the majority of students had changed their opinion about the loudness levels in the discotheques, and believed they should be reduced, whereas the minority then regarded them as fine. The authors explained, "This is an im0portant result of the campaign (hopefully) -- not because it will motivate adolescents to go to the discotheques less frequently or to use earplugs from now on -- but because it will make them open-minded towards sound level reduction in discotheques." And then later, the authors suggested possible financial subsidies be offered to clubs which will voluntarily limit their sound level. I thought that was a fantastic idea!

3. Age and noise-induced hearing loss. Esko Toppila et. al. Scandinavian Audiology (2001)
This study looked at age and noise exposure as factors in high-risk occupational noise environments. The goal was to determine significant factors to susceptibility. What the researchers found was that age is the most-correlated factor, but also significant were the factors of elevated cholesterol levels and use of analgesics (greater than 20 pills per month). Unfortunately (or maybe fortunately in the larger picture), the article states that, "The inner ear in older subjects seems to be more vulnerable to noise than those in younger ones." This is good for young people in the larger picture but it puts a cramp in the style of this research because it insinuates that young people can afford to ravage their ears when they simply can't!


4. Young people: Their noise and music exposures and the risk of hearing loss. Thais C Morata. Int'l Journal of Audiology (2007)
This editorial piece discussed both sides of the young adults and noise exposure argument. On the one hand, noise is everywhere and it's only getting louder. Morata states, "...ever increasing intensity levels during concerts and at nightclubs has made music exposure the most studied source of excessive sound exposure to children and youths in several countries." But Morata also intimates that some researchers believe that there is a, "...possibility of a toughening protective effect of such exposures..." (Fleisher and Muller, 2005, an article I'd love to read).
Morata cites another study by Fleisher and Muller that found that, "...orchestra musicians, despite their exposure, had the best hearing thresholds among several occupations and non-exposed groups."
But I wonder, are good thresholds the chicken or the egg? It could be that people who are in orchestra are more likely to have better thresholds in the first place and/or tougher, more responsive ears which bolsters their talent. The author also mentions that, "The prevalence of high frequency hearing loss has decreased over the twenty-year period, while the prevalence of audiometric 'notches' remained constant... Is it too soon to detect the effects of more recent technology? Possibly yes, since the findings from the study do not demonstrate any systematic, measurable effect on entrance audiograms."
I agree that it's too soon to tell. Twenty years is a long time, I wonder what the statistics would show if the author had looked at only the last five or ten years, when the 'bigger, badder, louder' culture started to arise. Lastly, a positive finding, "This evidence suggests that long term school-based programs can effectively increase the use of hearing protection among students, and sheds some light on approaches that ought to be considered for increasing awareness of the value of hearing and means of preventing disorders." This gives me hope that if we discover something that can be utilized in a long-term prevention program, students may be affected!

5. Music exposure and Audiological findings in Brazilian disc jockeys. Lorayne Santos et. al. Int'l Journal of Audiology (2007)
This article was mildly distressing. Forty Brazilian disc jockeys were studied in their work environments, which happened to be 93.2-109.7 dBA for approximately 8 hours at a time. 74% of the DJs reported tinnitus, and only 33% indicated that they used hearing protection at all. 27% of the participants already had thresholds above 25 dB and TEOAE testing showed that their exposure was dangerous. However, despite the information, the authors reported, "Even when the DJs learned about the test results, they indicated that they did not think the situation needed any change. They indicated they would like to learn more about flat attenuation ear plugs, but did not anticipate starting to use them." That is distressing because one would imagine that in an environment where hearing is so important to the occupation, employees would take steps to preserve what they have left. Will young adults feel the same way about their exposure, seeing that they are not exposed to quite as much noise as Brazilian disc jockeys?


6. Influence of music and music preference on acceptable noise levels in listeners with normal hearing. Susan Gordon-Hickey and Robert E Moore. Journal of American Academy of Audiology (2007)
This article described the ANL (Acceptable Noise Level) as the "maximum level of background noise that an individual is willing to accept while listening to speech." A previous article had listed music as the least-accepted noise, requiring 14.47 dB of gain for speech before listeners reported being comfortable with listening to a long narrative without getting lost. For this study, however, participants reported being comfortable at a significantly higher level of music (lower S:N ratio) at 6.25 dB gain of speech over music.
Some of the discussion hinted that the ANL may differ across genres based on preference or lyrical content, or other factors. The previous study (Nabalek et al, 1991) had used Muzak whereas the present study used contemporary rock music. Also worth mentioning is that the present study utilized young adults (mean age 23.54 years) and stated, "This group may be less distracted by and more accepting of background noise composed of music," because they're more likely to encounter background music in their lives. However, it's important to note that, "The results of this ANOVA (removing participants who recognized the music's artist/song name and redoing the statistical analysis) were the same, suggesting that familiarity may not influence ANL to music."