Electronic Letters to:
|
|
eLetters: Electronic letters published:
-
![[Read eLetter]](/icons/misc/sectionDOWN.gif)
Reason for discontinuing clozapine:case-control comparison with risperidone long-acting injection
- Hafsa Sheik, Dr Bettahalasoor Somashekar, The Caludon Centre, Coventry and Warwickshire Partnership trust, coventry CV2 2TE (19 March 2009)
-
Reply to Drs H. Sheik and B. Somashekar
- Professor David M Taylor (30 March 2009)
-
Clozapine: A Whipping Boy!
- Preeti Parakh, Ashutosh Kumar, Gauri Shankar, Madhvi Rughoo, Ashish Nair and Abhishek Pathak (28 October 2009)
-
Response to Drs Preeti Parakh, Ashutosh Kumar, Gauri Shankar, Madhvi Rughoo, Ashish Nair and Abhishe
- David M Taylor (10 November 2009)
|
|
|||
|
Hafsa Sheik, Dr The Caludon Centre, Coventry and Warwickshire Partnership Trust, Coventry CV2 2TE, Dr Bettahalasoor Somashekar, The Caludon Centre, Coventry and Warwickshire Partnership trust, coventry CV2 2TE
Send letter to journal:
drhafsasheikh{at}yahoo.com Hafsa Sheik, et al.
|
We read this article by Taylor et al (1) with a deal of great interest. We would like to raise some concerns with regards to the methods and conclusions of the study. The author has adopted rather crude methods to address the research question. He failed to use any psychiatric rating scales to assess the severity of mental illness among the both groups. Similarly the author did not use any objective parameters for physical health. Though the author has reported both groups are matched by age and gender, however it is more than likely that Clozapine group have more severe and longer duration of mental illness. There is evidence to suggest that the prevalence of physical diseases is higher in patients with severe mental illness (2). Therefore both groups should have also been matched in physical health parameters such as hypertension, diabetes, hyperlipidemia, chronic obstructive lung disease, smoking, cerebro vascular disease and coronary heart disease. There is strong possibility that the higher physical morbidity in this study can be independent of use of colzapine We believe that wide ranges of confounding factors related to mental and physical health were not properly matched. Therefore the findings of this study are very misleading. The Author’s occlusion that Clozapine use in patients with severe mental illness is associated with significantly high risk of death compared with that of the general population appears to be unfounded We would like to seek clarifications from the author. Reference: 1. Taylor D M, Douglas P, Olofinjana B, Whiskey E, Thomas A. Reason for discontinuing clozapine: matched, case-control comparison with risperidone long-acting injection. British Journal of Psychiatry 2009; 194:165-167. 2. Phelan M, Stradins L, Morrison S. Physical health of people with severe mental illness. BMJ 2001; 322: 443-444 |
|||
|
|
|||
|
Professor David M Taylor, Chief Pharmacist Maudsley Hospital
Send letter to journal:
david.taylor{at}slam.nhs.uk Professor David M Taylor
|
The correspondents point out limitations of our study which were largely covered in the original paper. It is possible that the clozapine group had more severe and long-standing illness and therefore poorer physical health. Nonetheless, this study emphasises the need for close physical monitoring of people on clozapine whether it be because of their psychiatric illness, their physical health, the use of clozapine, or any combination of these factors. Our finding that patients taking clozapine had a significantly increased mortality is robust and in line with other findings. We were careful not to ascribe this increase to clozapine itself in the paper. |
|||
|
|
|||
|
Preeti Parakh, Junior Resident in Psychiatry Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, Ashutosh Kumar, Gauri Shankar, Madhvi Rughoo, Ashish Nair and Abhishek Pathak
Send letter to journal:
drpreeti9{at}yahoo.co.in Preeti Parakh, et al.
|
The article raised some queries in our minds. The authors state in the abstract that their aim is to compare the reasons for discontinuation of clozapine with that for risperidone long-acting injection. They, however, conclude that clozapine is associated with a significantly increased risk of death compared to that of the general population and that the common causes of clozapine discontinuation are death and adverse effects. Their conclusions not only seem unrelated to their stated aim but also are far-fetched considering their study design. None of the mortalities in the clozapine group occurred due to an established adverse effect of clozapine and the deaths could very well have been due to a concurrent physical illness or due to the poor hygiene and nutritional status often found in chronic schizophrenics or even due to the cumulative adverse effects of all the drugs the patient had been on prior to starting clozapine. The authors themselves have acknowledged that their failure to collect information on concurrent medical illnesses, smoking status and duration of illness could have confounded the results. Moreover, since schizophrenics are known to have a higher risk of death from natural causes than the general population, ascribing a contributory role for clozapine in the deaths, without even attempting to assess the other factors that could have affected the outcome, is not only precipitous but also imprudent. The patients who have to be put on clozapine are more likely to have a refractory illness than those on risperidone long-acting injection. Clozapine is also likely to have more disabling side-effects than long- acting risperidone. In spite of this, the clozapine group persisted longer (mean 12.3 months) with the treatment before discontinuation than the risperidone group (mean 5.9 months). This, in our opinion, is an important finding of the study, which has been ignored by the authors. This, along with the fact that the authors jumped the gun in attributing an increased mortality risk to clozapine, suggests a bias against clozapine. |
|||
|
|
|||
|
David M Taylor, Chief Pharmacist Maudsley Hospital
Send letter to journal:
david.taylor{at}slam.nhs.uk David M Taylor
|
Almost all of the points raised by your correspondents are discussed in the original paper. Three additional points need addressing. First, I see no reason to exclude incidental findings from a study report simply because they were not included in the original aims of the study. Second, it is not far-fetched to conclude that people with schizophrenia treated with clozapine have a higher mortality than the general population. Every other study in this area has found exactly the same outcome. Indeed, mortality is higher in schizophrenia than in the general population in people receiving any antipsychotic (1). Third, I do not believe there is any bias against clozapine in the paper. We simply reported our findings. 1.Tiihonen J, Lonnqvist J, Wahlbeck K et al. 11-year follow-up of mortality in patients with schizophrenia: a population-based cohort study (FIN11 study). Lancet 2009;Epub ahead of print-DOI:10.1016/SO140- 6736(09)60742-X. |
|||