The session analysed some of the difficulties concerning methodology relating to endpoints in trials.
Dr F. Zannad, Nancy, FR discussed the difficulties in defining cardiac heart failure (CHF) in the different treatment trials in hyperlipidemia, hypertension and diabetes. The problem of defining heart failure is relevant in the prevalence (between 4 and 13.5%) and in the mortality rate. The definition varies in different studies (Europa, ACTION, PRO ACTIVE and UK-PAS etc). Something similar happens with the meaning of hospitalisation: sometimes it’s prevalent and other times, incidental. Considerable variability is produced when there are cut-off points in the ejection fraction, while maximum dispersion is observed in heart failure with preserved systolic function. Dr. Zannad proposes the use of criteria from the IX Cardiovascular Clinical Trialists’ Book.
Dr. Borer spoke about the cardiovascular safety of non-CV drugs. Drugs that are considered neutral from a CVD standpoint can, in certain cases, produce adverse CVD events. He stated how to minimise this problem by matching reasonable safety and maintenance of incentives for research and production in the pharmaceutical industry. After reviewing the definitions of serious adverse events (SAE) he affirms that before the labelling of new drugs, its effectiveness and acceptability must be tested. He reminded us that surrogate endpoints are certain conditions which statistically predict events, but only hypertension has shown this characteristic. Pathophysiological links must be found between non cardiovascular drugs and CVD effect. He also stated that designs used at present are not sufficiently effective to prove the benefits of these drugs.
Dr. Kjeldsen spoke about new onset diabetes (NOD) as a factor that significantly increases mortality rate, as well as the incidence of myocardial infarction and, in general, cardiovascular disease in a 5-year follow-up. The incidence of NOD in trials is between 5 and 15% (HOPE, LIFE, ALLHAT). He reviewed some important studies such as ARB, ASCOT, and VALUE, where he showed that the use of angiotensin-II blockers significantly reduced the relative risk of NOD, possibly through the improvement of peripheral sensitivity to insulin.
Dr. Hevey discussed whether quality of life (QoL) must be a new, valid target. The QoL concept is intuitive. There are more than 100 definitions. He promotes a QoL concept based on health-related QoL (HRQoL), which means wellness: functional, mental, social, and symptomatic. He challenged the normal endpoints (death, disease and dollars!) to other more complex endpoints related with QoL concepts, which are stated in the Scientific Advisory Committee of the Medical Outcome Trust. He recommends specific tools for peripheral disease, angina and heart failure.