Monday October 21 2013
Are you one of the ‘worried well’; a regular visitor to ‘Dr Google’?
“Cognitive therapy study hope for hypochondria patients,” reports the BBC News website.
The news is based on a UK randomised controlled trial of 444 people judged to have health anxiety, more commonly known as hypochondria.
Hypochondria is a mental health condition in which a person obsessively worries about their health, usually to the point where it causes great distress and affects their ability to function properly.
Participants were allocated to either receive five to 10 sessions of cognitive behavioural therapy (CBT) or standard care. The researchers were interested to see if there was a change in health anxiety at a follow-up of one year. They also assessed whether the interventions were similar in cost for up to two years afterwards.
The study found that after one year, CBT reduced self-reported health anxiety more than standard care. In terms of costs, they found that although the treatments did not cost the same, they were not significantly different.
Overall this study’s results are promising, though there remain some limitations. These include that the majority of eligible people with high health anxiety scores were unwilling to participate in the trial, which may mean the treated population is not representative. It is also unclear what the ‘standard care’ control involved and whether some people could have received other behavioural interventions.
Nevertheless, this was a good quality study that lends further support to CBT, already a well established treatment for many mental health conditions.
Where did the story come from?
The study was carried out by researchers from the Centre for Mental Health at Imperial College, the University of Bath and the London School of Hygiene and Tropical Medicine, among other institutions. It was funded by the National Institute for Health Research’s Health Technology Assessment Programme. The study was published in the peer-reviewed medical journal, The Lancet.
The story was picked up by the BBC News and The Times, who reported it appropriately.
What kind of research was this?
This was a randomised controlled trial (RCT) comparing a modified type of cognitive behaviour therapy (CBT) to standard care among a group of people with health anxiety in the hospital setting. The researchers were also interested in the cost-effectiveness of the modified CBT therapy. The trial was carried out in multiple centres in the UK.
An RCT is the best type of study design to determine whether a treatment is effective. It compares the effects of an intervention or treatment with another intervention or a control (such as a placebo). Participants are randomly allocated to which of these they receive, which should balance out any other differences between the groups which could otherwise confound the results.
The current study is said to follow the positive results of an earlier pilot trial.
What did the research involve?
Firstly, the researchers screened almost 29,000 people attending clinic appointments at six general hospitals in the following specialty areas:
- endocrinology (hormone related)
- respiratory medicine
To be included in the study, participants had to meet criteria for ‘excessive health anxiety’. This was initially assessed using a self-report form (Health Anxiety Inventory anxiety index [HAI]), and those scoring highly were further assessed using recognised criteria for diagnosis of hypochondria. Participants also had to be aged 16 to 75 years and live within the catchment areas of the hospitals.
Of the 5,769 people who scored highly on the HAI, 76% of them declined to participate in the trial.
The researchers then randomised the 444 people who met inclusion criteria and were willing to participate to receive either:
- modified cognitive behavioural therapy (CBT) consisting of a group of five to 10 sessions plus standard care (considered the active treatment) – 219 people
- standard care alone (considered the control treatment) – 225 people
‘Standard care’ was not further described by the researchers, so it is unclear what treatment these people may have received.
Therapists delivering the modified CBT were graduate research workers, nurses or other health professionals who were trained to deliver the intervention at two workshops.
The main outcome the researchers were interested in was change in health anxiety symptoms measured by the Health Anxiety Inventory (HAI) at one year follow-up.
HAI was also assessed at three and six months and at two years. The other main outcome of interest was whether the cost of the intervention was the same as health and social care costs over a two year period. The researchers collected ‘service use’ data for this economic evaluation at the beginning of the study, at six and 12 months and at two years.
Other assessments were made for anxiety and depression, health-related quality of life and social function and these assessments were carried out at six and 12 months and at two years.
Assessments were carried out by research assistants who were blinded to which intervention the participants were assigned.
The researchers then used appropriate statistical techniques to analyse their results for the comparison between treatments.
What were the basic results?
The main finding of the study was that after one year, people receiving modified CBT had a significantly greater reduction in health anxiety compared to people who received standard care alone (difference of 2.98 points on the HAI assessment tool, 95% confidence interval [CI] 1.64 to 4.33). Health anxiety was significantly reduced at all other assessments (three and six months and at two years) among the modified CBT group compared to the standard care alone group.
Other findings of the study included:
- After one year, 14% of the participants assessed who had received modified CBT had levels of health anxiety in the normal range (HAI score of 10 or less) compared with 7% in the group that received standard care alone (odds ratio 2.15, 95% CI 1.09 to 4.23).
- There was no significant difference in social functioning or health-related quality of life between the groups.
- People receiving modified CBT showed significantly better improvements in self-rated generalised anxiety and depression symptoms at six and 12 months compared to standard care alone. This remained significant at two years for generalised anxiety but not for depression.
- The average cost of the modified CBT intervention was £421.51 per person for an average of six sessions over a two year period.
- Equivalence in total two year costs of modified CBT compared to standard care alone was not achieved, but the difference in cost between the interventions was not significant (adjusted mean difference £156, 95% CI -1,446 to +1,758).
How did the researchers interpret the results?
The researchers concluded that this type of modified CBT is relatively cheap with an average of six sessions of treatment, and is effective in reducing health anxiety both in the short-term and up to two years after treatment, and also reduces generalised anxiety and depression. They said that health professionals with no previous training in the modified CBT treatment were shown in the study to be successful practitioners, and that the treatment could be generalised easily to hospital settings.
This study provides moderate evidence that after one year follow-up, a modified form of cognitive behaviour therapy reduced self-reported health anxiety more than standard care among a group of people attending hospitals for clinic appointments who met diagnostic criteria for hypochondria (health anxiety). It is not known whether these participants had other diagnosed mental health conditions.
This study had numerous strengths including its study design – a randomised controlled trial – the gold standard in evidence based medicine.
The main limitation of the study was that a large number of eligible participants declined to participate – of the 5,769 eligible based on their anxiety scores, three-quarters declined to participate.
So the treated population may have differed from those who declined to participate and may not be representative of the majority of people with health anxiety. For example, they may have improved awareness of their condition and be more willing to try behavioural therapies; denial about hypochondria may be common in people with the condition.
Another limitation worth noting is that the authors did not describe what the standard care involved. Though it is assumed that ‘standard care’ meant continued care for their health conditions without the specific CBT intervention being studied, it is not known whether some people in the control group may have received other behavioural or pharmacological treatments for anxiety or other mental health conditions.
Overall, this was a good quality study that lends further support to CBT, already a well established treatment for many mental health conditions. Read more about health anxiety (hypochondria)
Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter