With the ageing population multimorbidity is a large and increasing public health concern. The health care for patients with multimorbidity is complex due to different treatment providers, different treatments and medication. Figures of multimorbidity are however scarce. Our objective is to present an overview of the prevalence of multimorbidity and comorbidity of chronic diseases in the Dutch population.
We used data of seven years of registration (2002 – 2008) of a large Dutch representative network of general practices (LINH), consisting of over 350,000 electronic medical records of patients. The analyses were performed for patients registered for three or more continuous years in a general practice registered in LINH. Multimorbidity was defined as registration of two or more of 29 chronic diseases in the electronic patient records. The prevalence of multimorbidity was calculated in the total population and for sex and age-specific groups. For patients of 55 years and older clustering of diseases was determined by logistic regression analyses adjusted for sex and age. Comorbidity (number of extra diseases) was calculated for the ten most prevalent chronic diseases for the aged: diabetes mellitus, coronary heart disease, arthritis, COPD, chronic neck- and back disorders, cancer, stroke, depression, heart failure, and anxiety disorder. In addition we explored the five most common combinations with the selection of ten chronic diseases.
Multimorbidity of chronic diseases was found in about 13% of the Dutch population and in 37% of patients older than 55 years. Among patients over 55 years with a chronic disease more than two-thirds had one or more extra chronic diseases. Most disease pairs occurred more frequent than expected based on independency of diseases (clustering). Diabetes mellitus, coronary heart disease, and arthritis were included in the five most common diseases for all ten chronic diseases. However, comorbidity was not limited to a few specific combinations of chronic diseases. About 70% of those with a chronic disease had one or more extra chronic diseases registered which were not included in the five most common diseases.
Over two-third of the aged with chronic diseases were registered with multimorbidity. Comorbidity encompassed many different combinations of chronic diseases. Recent changes in health care include disease-specific treatment programs (disease management programs) for some chronic diseases, which do not account for the large variety of multimorbidity. The finding that multimorbidity cannot be captured with a few common combinations of diseases represents a challenge for all disease-specific approaches. With the further ageing population multimorbidity should be taken into account for the organization of care, in scientific research and in health care policy.
This supplementary information is presented as submitted by the corresponding author. It has not been copy-edited by NTvG.