Over diagnosis poses threat to health

Over diagnosis poses a significant threat to human health by labeling healthy people as sick and wasting resources on unnecessary care, a senior researcher at Bond University in Australia has warned. Over diagnosis occurs when people are diagnosed and treated for conditions that will never cause them harm and there's growing evidence that this occurs for a wide range of conditions. For example, a large Canadian study found that almost a third of people diagnosed with asthma may not have the condition; a systematic review suggests up to one in three breast cancers detected through screenings may be over diagnosed; and some researchers argue osteoporosis treatments may do more harm than good for women at very low risk of future fracture. Many factors are driving over diagnosis, including commercial and professional vested interests, legal incentives and cultural issues, said Ray Moynihan, Senior Research Fellow at Bond University, and co-authors, Professors Jenny Doust and David Henry. Ever-more sensitive tests are detecting tiny " abnormalities" that will never progress, while widening disease definitions and lowering treatment thresholds mean people at ever lower risks receive permanent medical labels and life-long therapies that will fail to benefit many of them. Added to this, is the cost of wasted resources that could be better used to prevent and treat genuine illness. But Moynihan argues that the main problem of over diagnosis lies in a strong cultural belief in early detection, fed by deep faith in medical technology. "Increasingly we've come to regard simply being 'at risk' of future disease as being a disease in its own right," he stated. A leading global authority on evidence-based practice, Professor Paul Glasziou from Bond University in Australia said: "As a side effect of our improving diagnostic technology, over diagnosis is a rapidly growing problem; we must take it seriously now or suffer the consequences of over treatment and rising health care waste." As Moynihan and colleagues write in a BMJ feature, concern about over diagnosis in no way precludes awareness that many people miss out on much needed healthcare. On the contrary, resources wasted on unnecessary care can be much better spent treating and preventing genuine illness, not pseudo-disease. "The challenge is to work out which is which, and to produce and disseminate evidence to help us all make more informed decisions about when a diagnosis might do us more harm than good," they concluded.