Friday May 25 2012
Could the sound of waves cure tinnitus? Not on its own.
People with tinnitus have been “advised to listen to the sea to cure ringing in ears”, according to Metro, the free commuters’ newspaper. Its story, which may seem comforting only to sailors and fishermen, is based on a new study that explored how best to help patients with tinnitus, a common distressing condition that causes a constant ringing or other noise in the ears.
The yearlong Dutch trial gave adults with tinnitus a standard package of care or a programme which added cognitive behavioural therapy (CBT) to elements of standard therapy for tinnitus. CBT is a type of therapy that challenges people’s negative assumptions and feelings to help them overcome their worries. Compared with those given usual care, the group receiving specialised treatment reported improved quality of life, and reduced severity and impairment caused by tinnitus.
This well-designed study found that using CBT alongside elements of standard therapy can help patients with tinnitus of varying severity. However, the differences in outcomes between the two groups were quite small, and this technique can only help manage tinnitus rather than curing it, as some papers implied. Also, the patients in the study were followed for only 12 months, so it is unclear whether this approach can help in the longer term.
Nevertheless, this is a promising step towards more effective management of this troubling condition.
Where did the story come from?
The study was carried out by researchers from Maastricht University in the Netherlands, the University of Leuven in Belgium, Bristol University and Addenbrooke’s Hospital in Cambridge. It was funded by the Netherlands Organisation for Health Research and Development (ZonMW). The study was published in the peer-reviewed medical journal The Lancet.
Many of the press headlines mentioned that listening to the sound of the sea could help tinnitus, with the Metro claiming this could cure the condition. However, sound therapies that try to neutralise tinnitus using soothing sounds, such as waves or birdsong, are not new, but are part of standard treatments for this condition. Also, the report in the Lancet did not state what kind of sounds were used as therapy. Sound therapy was not the only treatment approach used, but was given as part of a specialised treatment programme delivered by expert health professionals.
What kind of research was this?
This randomised controlled trial (RCT) compared a multidisciplinary approach for tinnitus that combined standard tinnitus retraining therapy with CBT. CBT is a talking treatment in which patients are taught to combat negative or “catastrophic” thinking.
The researchers point out that up to one in five adults will develop tinnitus, a distressing disorder in which people hear buzzing, ringing and other sounds from no external source. Tinnitus can occur in one or both ears, and is usually continuous but can fluctuate. A randomised controlled trial is the best way of assessing the effectiveness of an intervention.
There is currently no cure for tinnitus. However, people who have tinnitus may be offered:
- sound therapy, in which neutral, natural sounds are used to distract them from the condition
- counselling sessions
- retraining therapy, in which people are taught to “tune out” their tinnitus
The authors of the new study say there is little evidence for any of the treatments offered when given in isolation, that treatment is often fragmented, and people with tinnitus are often told they have to “put up with it”.
CBT could potentially help people with tinnitus deal with fears that their tinnitus might be caused by brain damage or might lead to deafness. During CBT, they might learn that the condition is common and that it is not associated with brain damage or deafness. They might also be exposed to the sound in a safe environment, so that it has less of an impact on their daily life. CBT also involves techniques such as applied relaxation and mindfulness training.
What did the research involve?
Between 2007 and 2011, the researchers recruited 492 Dutch adults who had been diagnosed with tinnitus. The patients had to fulfil several criteria, including having no underlying disease that was causing their tinnitus, no other health issues that precluded their participation, and to have received no treatment for their tinnitus in the five previous years. Some 66% of adults originally screened for the study participated after screening.
The patients were assessed at the start of the study for their hearing ability and the severity of their tinnitus. The researchers assessed the degree of severity using established questionnaires, which looked at health-related quality of life, the psychological distress associated with tinnitus and how far it impaired their functioning. Using this information, researchers divided participants into four groups ranked on the severity of their condition.
Participants were then randomly assigned one of two forms of treatment. This was carried out using a computer-generated method of randomisation. Neither patients nor researchers knew which treatment participants had been assigned.
One group of 247 patients received standard (usual) care for tinnitus. This included audiological checks, counselling, prescription of a hearing aid if indicated, prescription of a “masker” if requested by the patient (a device that generates neutral sounds to distract from the noise of the tinnitus), and counselling from social workers when required.
The treatment group (245 patients) received some elements of standard care (such as a masking device and hearing aid if needed), but also received CBT. The CBT included an extensive educational session, sessions with a clinical psychologist and group treatments involving “psychological education” explaining their condition, cognitive restructuring, exposure techniques, stress relief, applied relaxation and movement therapy.
In both groups, a stepped approach was taken to care. This is where the level of care provided is based on individual need, with a gradual increase in the intensity of care as required. Step 1 and 2 in both groups were completed by 8 months, and followed by a no-contact period of 4 months before a follow-up assessment at 12 months.
The researchers assessed the participants before treatment, and at 3, 8 and 12 months after treatment began. The main outcomes they assessed were:
- health-related quality of life, as assessed on a 17-item questionnaire which considers aspects including vision, hearing, speech, ambulation, dexterity, emotion, cognition, and pain or other complaints
- tinnitus severity on the Tinnitus Questionnaire, which consists of 52 items rated on a 3-point scale and assesses the psychological distress caused by tinnitus
- tinnitus impairment on the Tinnitus Handicap Inventory, which is described as a 25-item instrument which assesses tinnitus-related impairment on three domains: functional, emotional and catastrophic
They compared outcomes between the two groups using standard statistical methods.
What were the basic results?
After 12 months, patients in the specialised care group receiving CBT had slightly greater improvement in health-related quality of life compared with those in the usual care group (between-group score difference 0.059, 95% confidence interval [CI] 0.025 to 0.094).
The results were calculated using a measure called “effect size”, which is a way of quantifying the size of the difference between the two groups. For the difference in quality of life scores between groups, the effect size was calculated to be 0.24. This can be interpreted as a “small” effect. In other words, treatment including CBT gave a small improvement in quality of life compared with usual care.
After 12 months, patients in the specialised care group also had reduced tinnitus severity (score reduction compared with the standard care group -8.062 points, 95% CI -10.829 to -5.295) and reduced tinnitus impairment (score reduction compared with the standard care group -7.506 points, 95% CI -10.661 to -4.352).
For the differences in severity and impairment scores between groups, the effect size was calculated to be 0.43 and 0.45 respectively. These can be interpreted as a “moderate” effect. In other words, the intervention gave a moderate improvement in tinnitus severity and impairment compared with usual care.
The researchers further reported that the specialised treatment seemed effective irrespective of the patients’ initial degree of tinnitus severity, and there were no adverse events.
However, the drop-out rate by 12 months was quite high: 86 (35%) patients in the usual care group and 74 (30%) in the specialised care group.
How did the researchers interpret the results?
The researchers said that specialised treatment of tinnitus based on cognitive behaviour therapy is more effective than standard care. They concluded that “specialised treatment of tinnitus based on cognitive behaviour therapy could be suitable for widespread implementation for patients with tinnitus of varying severity.”
This well-designed study found that a multidisciplinary approach which combines elements of standard therapy with a form of talking therapy called CBT can help patients with tinnitus of varying severity.
This study has several strengths. It included a relatively large number of patients, reducing the possibility of bias by “masking” which treatment patients received, classifying participants according to the severity of their tinnitus and using highly standardised interventions. Also, the researchers used established scales to measure the severity of tinnitus and its impact on quality of life.
However, the multidisciplinary approach based on CBT is not a “cure for tinnitus”, as implied in some papers, but rather a system for managing its symptoms and effects on people’s lives. The differences in outcomes between the treatment and usual care groups were quite small, with the multidisciplinary approach giving a small improvement in quality of life compared with usual care, and moderate improvements in tinnitus severity and impairment. Also, less than 70% of participants completed the trial to 12 months, and this could have affected the reliability of the study’s overall results. Furthermore, as the patients in the study were only followed for 12 months, it is uncertain whether this approach can help in the longer term.
The multidisciplinary approach required input from many different professionals including audiologists, psychologists, speech therapists and physical therapists. Which particular care elements of the intervention had the greatest effect is unknown. A multidisciplinary approach such as the intervention trialled here may have resource implications if it were introduced into standard clinical practice.
Nevertheless, this is a promising step towards more effective management for this troubling condition.