Here's an article that caught my attention about extracting more information from a diagnostic study than the ordering clinician was seeking (see: Chest CT Scans Predict Cardiovascular Event Risk). Pulmonologists will order a chest CT for various reasons such as follow-up of a standard chest x-ray, diagnosing the cause of lung symptoms such as shortness of breath, or a search for a lung tumor or pulmonary embolism (see: What Is a Chest CT Scan?). The authors of a study developed a prediction model for future cardiovascular disease for patients undergoing a chest CT based on information readily available to any radiologist interpreting the scan. These include patient demographics in addition to cardiac and vascular imaging findings. Below is an excerpt from the article:
A new study finds that, in addition to being used for diagnostic purposes, incidental chest computed tomography (CT) findings can help identify individuals at risk for future heart attacks and other cardiovascular events. Study authors...note that patients at high risk for cardiovascular events are currently identified through risk stratification tools based on conventional risk factors such as age, gender, blood pressure, cholesterol levels, diabetes, smoking status, or other factors thought to be related to heart disease. Their research, they say, provides “a different approach for cardiovascular disease risk prediction strictly based on information readily available to the radiologist....The final prediction model included age, gender, CT indication, left anterior descending coronary artery calcifications, mitral valve calcifications, descending aorta calcifications, and cardiac diameter. ...[T]his model was found to accurately place individuals into clinically relevant risk categories, and the results demonstrated that radiologic information “may complement standard clinical strategies in cardiovascular risk screening, and may improve diagnosis and treatment in eligible patients.” [The lead author] points out that the risk score the authors developed is based on incidental CT findings, adding that most diagnostic CT scans are ordered by medical specialists such as pulmonologists or surgeons, for example, rather than primary care physicians.
A question that occurred to me with regard to this article is whether it is appropriate to extract as much information as possible from a radiology study even if that information was unrelated to the reason for ordering the study in the first place and not asked for by the clinician To be more specific and in the case described here, a chest CT was probably ordered to assess pulmonary disease. The radiologist, in addition to diagnosing any lung disease. supplies additional information in the report about the likelihood of the patient developing cardiovascular disease in the future. This is both similar and different to the case of incidentalomas that I have discussed in previous notes (see: How to Avoid the Risks of a CT Incidentaloma; More (and Interesting) Discussion about Incidentalomas).
The case is similar to incidentalomas in that it involves the reporting of disease beyond that being sought by the clinician when the chest CT is ordered. The case is different than incidentaloma in that some benign lesions of the lung may be better undiscovered. The reporting of a probable benign lesion of the lung may result in added expense and mortality if the treating clinician feels pressured to confirm that the lung lesion is benign. In the case described here, a patient is always better off being informed that he or she may be at increased risk of future heart attacks and other cardiovascular events. The clinician and patient can then take steps to forestall such future events. In effect, greater diagnostic utility is being extracted from the relatively expensive CT chest scan than was intended at the time of the order.