UUN: s1259324

CRITICAL APPRAISAL- DIABETES AND ENDOCRINOLOGY

Introduction

This critical review discusses the article Effectiveness of a diabetes education and self management programme (DESMOND) for people with newly diagnosed type 2 diabetes mellitus: three year follow-up of a cluster randomised control trial in primary care by authors Kamlesh Khunti, Laura J Gray, Timothy Skinner, Marian E Carey, Kathryn Realf, Helen Dallosso, Harriet Fisher, Michael Campbell, Simon Heller, Melanie J Davies. It is published in the British Medical Journal and funded by a grant from Diabetes UK. The authors declare no conflict of interest and have received ethical approval by the Huntingdon local research ethics committee.

Importance of the study

This study addresses newly diagnosed patients of Diabetes mellitus type 2 and whether or not diabetes education and self-management programmes provide benefits after 3 years. Considering the fact that diabetes type 2 accounts for approximately 90% of people with diabetes and that the number of people with diabetes has increased from 1.4 to 2.6 million since 1996,i the study is an important one although, it is not clear why the authors decided to go with DESMOND alone and why they chose three years for follow-up. However, it is worth knowing if these programmes are benefitting patients and whether these benefits persist in the long run.

Title and study design

The title chosen is self-explanatory and outlines clearly what the study is about. It mentions which programmes they have focussed on – DESMOND and the population they are looking at – newly diagnosed people with Diabetes Type 2. It also mentions that it is a three-year follow up of patients in primary care settings. It is a cluster RCT and the abstract mentions that it involves 207 general practices in 13 primary care units in the UK.

Originality of the study

The authors have mentioned what the study adds and what we already know about the subject in a table on page 6. They say that no study up until then had evaluated the long term impact of these self-management programmes and therefore it can be seen why this study was needed. There are still some aspects, however that need evaluation and this study is somewhat one-dimensional. They have said that the “optimum interval and contact time” needs further evaluation. Their study concludes the fact that these programmes do not help much in the long run except in illness beliefs. They outline the meaning of illness beliefs in page 3 and in table 1 as coherence, timeline, personal responsibility, seriousness and impact score and say that this had differed significantly over three years. However, one has to wonder if the difference in these illness beliefs may be due to the fact that the patients’ have had the disease for a considerable time and simply living with diabetes gives

a greater understanding of it and clears false perceptions or whether it really was the effect of the self-management programmes. The positive conclusion that the authors have made about illness beliefs may or may not be linked to the education programmes.

Population and the inclusion-exclusion criteria

In the “Methods” section, the authors have mentioned that the participants were referred within six weeks of diagnosis in the original trial and within 12 weeks of diagnosis in the intervention arm. They excluded people who were aged less than 18 years, had severe and enduring mental health issues, were not primarily responsible for their own care, were unable to participate in a group programme or were participating in another research. The inclusion criterion is not very clear and they may have excluded too many people with the resulting group being too similar and therefore resulting in bias.

Randomisation

Randomisation is described in the “Methods” section and it seems that the details have been mentioned in another report which was done at the 12 months follow up. The randomisation technique seems to be quite good. It was done first at the general practice level and then randomised using a Random log at the University of Sheffield. A local coordinator oversaw the trial, recruited, trained and maintained contact with the practice. However, there may have been some degree of bias at the coordinator level as they were monitored only once a year and received all the biomedical data before forwarding it on. The study was not blinded which is acceptable considering the relatively objective nature of both the primary and secondary outcomes.

The Intervention Group

The intervention group is well described and detailed. They had a written curriculum and the programme was delivered through trained staff for six hours in one day or divided into two days. Although, it seems as though DESMOND delivers a six hour programme in one full day rather than two and it is not clear whether this has had an effect on the result in favour of the intervention arm. Participants were sent a questionnaire by post two weeks before the follow up date.

They have not described the control arm clearly. The abstract section mentions that the intervention was delivered by “health care professional educators compared with usual care” and similarly in “The intervention” they mention that it was “integrated into routine care” but it is not clear what that is.

Primary and Secondary Outcomes

The primary outcome was glycated haemoglobin levels and the secondary outcomes included blood pressure, weight, smoking status etc. The writers report improvement across all the areas, with no significant difference (-0.02 with 95% confidence interval -0.22 to 0.17) between the two groups after adjusting for baseline and clustering. The only significant difference was in some of the illness beliefs in which the intervention group scored

significantly higher. Depression, quality of life and other such scores showed no difference. The non-smokers showed significant difference in the intervention arm at 12 months but this improvement was not sustained at three years. The reason for this is unclear and may be detailed elsewhere. However, reading a little about the changes that were seen at four, eight and twelve months and comparing them to those at three years would have been interesting.

Statistical Analysis

The researchers used standard deviation of glycated haemoglobin to calculate the sample size required for a clinically significant difference of 1% at 12 months with 90% power at 5% significance level. After assuming that 20% would not consent and 20% would dropout, they required 500 participants in each arm. They also used the intention to treat protocol and approximately 80% of the participants should be and were accounted for at the end of the trial (last table on page 12- followed up at 3 year 79.3% of the control and 85.6% of the intervention). The greater number of participants in the intervention arm may have resulted in bias.

Clinical Relevance and Importance of the Result

The main point of what the study set out to determine was answered in the statement in the “Discussion” section – After three years the impact of a single structured education intervention delivered to people with newly diagnosed type 2 diabetes mellitus was not sustained for biomedical and lifestyle outcomes, although some changes in illness beliefs were still apparent. This basically tells us that these self-management programmes are not achieving their goals in having benefits in the long run. It is not clear if further down the line, the improved illness beliefs will remain consistent. However, these self-management programmes can figure out a way to reinforce the message after a period of time using these studies. The authors mention this in the last paragraph of “Discussion”- The findings of these studies will help to determine the optimal contact time and frequency of education sessions required…

The authors also say in the same paragraph that a key aspect of the study was to show at what point any benefits of the intervention begin to diminish and they have not managed to address this issue.

As far as clinical relevance is considered, it is not a study that will help all settings. Many clinical settings do not deal with, refer or even have self management programmes in their respective areas and therefore it is only helpful for places where these programmes and/or services are promptly and easily available.

Other Aspects of the Study

The authors have compared their study and how it is different from others conducted on the various self-management programmes and it is nicely done. Reading about how the other studies differ from the current one and what differences there are between these education programmes in a brief way, makes it easier to understand why they did this

research in the first place. The first line of “Comparison with other studies” highlights this point- Evidence of long term impact of structured education interventions in people with diabetes is currently lacking.

The authors have highlighted, in an honest and concise way, the strengths and limitations of their study under a separate heading. In brief, the strengths included:

- cluster randomised control trial (missing data has less impact)- reasonably well matched participants in both arms- minimising contamination- intention to treat analysis- good response rates after three years- reproducible and fairly generalizable

and the limitations of the study included:

- underpowered (type 2 errors)- selection bias (participants at follow up were older, healthier and less depressed)

Grammar and Style of the Study

The study was grammatically good but the style was a little haphazard. It was not hard to read but it felt like there was a lack of flow to it. However, the use of headings was good and clear. The tables could have been incorporated into the paper instead of at the end.

Summary

This article manages to highlight some important issues with the current strategy used by diabetes education and self-management programmes, specifically focussing on DESMOND. Diabetes mellitus type 2 is a growing concern all over the world and programmes like DESMOND aim to reduce some of the general misconceptions about the disease and ease newly diagnosed patients into it by giving them important information. Some illness beliefs were found, by this study, to have lasted three years on but the rest of the biomedical and psychosocial impacts had not. Perhaps, further studies on how to improve and reinforce the message of these programmes are required, for example, at what point do patients start to forget the message and when and how a reinforcement message will help. This study does fill in the blank to a certain extent.

Rapid Critical Appraisal of an RCT [online]. The National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) South West Peninsula. Available from: http://clahrc-peninsula.nihr.ac.uk [Accessed 06/04/2014].

REF

(1) http://www.diabetes.org.uk/Documents/Reports/Diabetes_in_the_UK_2010.pdf(2) http://clahrc-peninsula.nihr.ac.uk/includes/site/files/files/CDM%20website%20material/2011-10-14_Critical_Appraisal_of_an_RCT%5B1%5D.pdf(3) Appraisal of an RCT using a critical appraisal checklist, Spink MJ, et al. Effectiveness of a multifaceted podiatry intervention to prevent falls in community dwelling older people with disabling foot pain: randomised controlled trial. BMJ 2011; 342: d3411. Available from: http://clinicalevidence.bmj.com [Accessed 06/04/2014].

i March 2010. Diabetes in the UK 2010: Key statistics on diabetes [online]. Diabetes UK. Available from: http://www.diabetes.org.uk [Accessed 06/04/2014].