Overdiagnosis and overtreatment: An epidemic hiding in plain sight

The remarkable advances in modern medicine have transformed once-fatal conditions into survivable illnesses. Yet, alongside such triumphs lies an under-appreciated epidemic: overdiagnosis and overtreatment. Increasingly, medicine is doing too much, too often and too soon – yielding little value and occasionally great harm. This phenomenon, while long recognised in high-income settings, is now gaining attention in LMICs (Low- and Middle-Income Countries), where scarce resources magnify its consequences.^1,2

Overdiagnosis is officially defined as the diagnosis of a condition that would never cause symptoms or death: it means unnecessary investigations, with subsequent inevitable overtreatment and thus avoidable harm in terms of complications, cost and psychological trouble. ³ Overtreatment includes the overuse of diagnostic imaging, cancer screening, unnecessary laboratory testing, random use and overuse of antibiotics and other medication, low-value surgical procedures, unnecessary ICU care and defensive medicine which divert huge resources away from essential care. A scoping review revealed that in nearly every clinical field this scourge of overdiagnosis exists, with oncology leading (50%), followed by mental health, infectious diseases and cardiovascular disorders. ³ Imaging technologies have expanded detection of incidentalomas, many of which pose no clinical threat but trigger cascades of testing and interventions. More recently, the rise of AI (Artificial Intelligence)-based interpretation of radiological imaging has introduced an additional layer to this already burgeoning conundrum of overdiagnosis, with leading experts cautioning against its potential to amplify detection of clinically irrelevant findings. ⁴ For LMICs, the cost of overdiagnosis is devastating. A BMJ Global Health review across 55 LMICs documented overuse of imaging, serological tests and tumour markers, with consequences ranging from unnecessary treatment to catastrophic household expenditure. ⁵ Few examples are as shocking as malaria overdiagnosis in Sudan which led to wastage of $86 million in 1 year – while exposing thousands to unnecessary treatment. ⁵

Overdiagnosis, however, remains poorly defined and therefore hardly understood and inconsistently communicated, while healthcare professionals themselves often lack awareness of its magnitude. Cancer screening exemplifies the paradox of benefit and harm. Screening reduces cause-specific mortality but simultaneously leads to significant overdiagnosis. ⁶ Thyroid cancer overdiagnosis, for example, has been described as a global epidemic, with rates >70% in some Asian countries. ⁷ Defining overdiagnosis, particularly in cancer screening, cannot be directly measured, but best practices emphasise clear definitions, transparent estimation and patient-centred communication ⁶ ; however, the overdiagnosis epidemic rages on, with striking gaps in health professionals’ understanding of this problem. ⁸ Indeed many clinicians conflate it with false positives and underestimate its harm.

In primary care, overdiagnosis is amplified by broad disease definitions and cultural beliefs. The inclusion of individuals not at risk of death within the normal follow-up period artificially elevates survival statistics, thereby creating a misleading impression of benefit. This inevitably promotes additional testing and exacerbates overdiagnosis. ⁹ The consequences are profound: psychological distress, unnecessary follow-up, time wasted and an extra financial burden. Such cascades are doubly harmful in LMICs where resources are limited.

Unnecessary Caesarean section is the single largest contributor to low-value surgery, with rates between 12% and 81%; its annual cost in China alone exceeds $3.2 billion. ¹⁰ Routine ‘prophylactic’ cholecystectomy for asymptomatic gallstones and axillary dissection for early breast cancer despite sentinel node biopsy options are other examples, quite apart from non-essential cosmetic surgery. ¹¹

ICUs (Intensive Care Units) epitomise high-cost care. A scoping review identified effective strategies to reduce low-value interventions such as the routine of daily chest radiographs and routine blood tests. ¹²

Overuse of medications is rampant in LMICs; with prevalence ranging from 7% to 98%; inappropriate antibiotic use particularly leads to an alarming frequency in antibiotic resistance. ¹³ Amazingly, absolutely no adherence to surgical prophylaxis guidelines was found in an Egyptian study! ¹⁴ Defensive medicine (ordering tests to avoid litigation) fuels cascades of irrelevant diagnoses. ¹⁵ Social media misinformation further pressures patients into demanding unnecessary tests, with most electronic posts presenting promotional rather than evidence-based information. ¹⁶

But what can be done?

Awareness of the new science of de-implementation is the first step to choose wisely; thereby it is possible to make evidence-based comparisons.^17–19 Smarter pre-operative testing interventions can reduce waste and improve efficiency. ²⁰ Mandatory second opinions, guideline enforcement and opinion-leader education can all reduce unnecessary surgical intervention.^21,22 De-implementation is a Global Health priority. Overdiagnosis and overtreatment are neither inevitable nor benign but cause active clinical, financial, psychological and environmental harm. For LMICs, antibiotic stewardship, smarter pre-operative testing and systemic reforms re-aligning incentives with value are essential. Minimising harm and waste is part and parcel of providing high-quality health services. Balanced effort to curb overdiagnosis and overtreatment may actually address the underuse of evidence-based care, and is crucial to achieving more equitable and higher-value healthcare.