New clinical guidelines need to be developed to help doctors provide better care for people with more than one chronic illness, according to a research team led by the University of Dundee.
In an article published in the British Medical Journal, the research team - which includes the Universities of Dundee, Glasgow and Manchester and the National Institute for Health and Clinical Excellence (NICE) - say that existing guidelines which concentrate on individual diseases are not best serving clinicians or patients where a number of chronic conditions have to be treated.
"Doctors and other professionals often use guidelines to inform their clinical decision making, and clinical guidelines have played an important part in making healthcare more consistent, efficient, and systematic," said Professor Bruce Guthrie, of the Medical Research Institute at the University of Dundee.
"Through the National Institute for Health and Clinical Excellence and the Scottish Intercollegiate Guidelines Network (SIGN), the UK is a world leader in guideline methodology, and guideline development and implementation.
"Despite their success, clinical guidelines are almost always focused on making recommendations about the treatment of individual diseases, which can make their use in clinical practice problematic. This is because most people with long term conditions have more than one chronic illness, particularly older people in whom multiple chronic illnesses (multimorbidity) are the norm.
"For example, 93% of people with coronary heart disease (heart attacks or angina) have at least one other chronic condition, and a fifth have five or more other conditions.
"This creates a paradox - every individual guideline recommendation may be rational and strongly evidence based, but the cumulative effect of recommendations for multiple chronic conditions may not be appropriate as recommendations are contradictory or treatments recommended interact, or because the burden imposed on patients in terms of numbers of drugs, non-drug therapies (diet, exercise, physiotherapy and so on), and attendance for investigation or follow-up may be overwhelming and not feasible for some people with multiple conditions.
"There will of course be many situations where all guideline recommendations are non-contradictory and appropriate, but previous studies in the USA have shown that guidelines there only occasionally address multiple conditions and recommendations are frequently inconsistent or would produce undesirable drug interactions if implemented.
"Decision making in this situation is complex for both clinicians and patients, but existing guidelines are not ideal for supporting either in deciding the best course of action because they are disease based."
Working with colleagues at the Universities of Manchester and Glasgow, and NICE, Professor Guthrie is leading a research project to implement a new approach to guideline development to help address these problems, and examine its methodological feasibility.
Professors Katherine Payne and Matt Sutton, from the Centre of Health Economics at The University of Manchester, are leading the economic component of the study.
Professor Payne said: "Economic evidence is often used to inform the development of clinical guidelines to provide decision-makers with information on the relative cost effectiveness of the individual interventions included in the guidelines. This study aims to explore if, and how, it is feasible to generate economic evidence to support the development of clinical guidelines involving multiple interventions for people with multiple chronic conditions."
Professor Guthrie added: "This work is exploratory, but if successful will make guideline recommendations more relevant for people with multimorbidity."
The project follows on from previous research published in The Lancet earlier this year by Professor Guthrie and colleagues which showed that having two or more co-existing conditions is the norm for most people with chronic disease, and although the prevalence increases with age, more than half of all people with multimorbidity are under 65.
That paper claimed that health systems in the UK and other developed countries were not devised to deal with this scenario and must be radically changed to cope.