Abstract
Hands up who understands the measurement and interpretation of the cardiac QT interval. Just as I thought: pretty much nobody. We all know the value of the upper limit of normal (about 450ms, isn’t it?), but what does one do if a patient has a QT of 451ms? Or 500ms? If a drug prolongs QT by 10ms is that something or nothing to worry about? Vieweg and colleagues, in this issue, review QT prolongation with methadone and associated cases of torsades de pointes and make the point that predicting adverse outcomes by known effect of a drug or by QT changes in an individual is near impossible. This is because those patients developing arrhythmia are statistical outliers whose arrhythmia is a result of numerous contributing factors.
Also difficult to predict is which patients will take medication prescribed to them. In this issue, Higashi and co-workers from the Netherlands examine factors affecting compliance in schizophrenia alongside outcomes related to non-adherence. Perhaps predictably (for once) non-adherence is clearly linked to relapse and suicide. More surprising is the finding that non-adherence is driven by lack of insight, medication beliefs and substance misuse – and not to any great extent by adverse effects of medication. This doesn’t seem logical but nor does much in the field of medication adherence: patients claiming not to want to take medication for the rest of their lives often smoke, drink and use illicit substances, often for the rest of their lives. Of course one way of assuring adherence in schizophrenia is to use depot injections. Enrico Smeraldi and colleagues report on their comparison of depot risperidone with oral quetiapine. The depot showed improved efficacy over quetiapine in terms of remission and secondary efficacy measures.
Mitra Safa and Iranian colleagues also describe their study of adding omega 3 fatty acid to fluvoxamine in major depression. The addition of omega 3 seemed to improve response compared with fluvoxamine alone. In most countries, this specific use of omega 3 would be seen as ‘off-label’. This is a phenomenon thoroughly reviewed by Philip Sugerman and colleagues in this issue. The authors go so far as to recommend a new, more practical method of prescribing governance; one that is better able to encompass new uses of licensed drugs.