Under-diagnosis of common chronic diseases: prevalence and impact on human health

The disability-adjusted life years (DALY) and its components, namely the years lived with disability and the years of life lost, are measures of the impact of disease on human health. Our impression was that several common chronic diseases responsible for many DALYs are frequently under-diagnosed.

We attempted to summarise data regarding the under-diagnosis of common chronic diseases of the developed world, which are associated with considerable mortality and/or disability. We searched PubMed and Current Contents to identify relevant studies (1980-2005). Two reviewers extracted data concerning DALYs and prevalence of under-diagnosis of common chronic diseases.

Studies regarding the first 15 diseases (or group of diseases) based on DALYs were reviewed. The under-diagnosis of common chronic diseases in the developed world ranges from about 20% for dementia and cirrhosis to 90% for depression and osteoarthritis. The delay in the prompt diagnosis and initiation of treatment is associated with increased morbidity and mortality for most of the reviewed diseases.

The available evidence suggests that the prevalence of under-diagnosis of common chronic diseases is considerable. Physicians should be aware of the prevalence of under-diagnosis of chronic diseases and its impact on human health.