Cost-effectiveness of follow-up of pulmonary nodules incidentally detected on cardiac computed tomographic angiography in patients with suspected coronary artery disease

Circulation. 2014 Aug 19;130(8):668-75. doi: 10.1161/CIRCULATIONAHA.113.007306. Epub 2014 Jul 11.


Background: Pulmonary nodules (PNs) are often detected incidentally during coronary computed tomographic (CT) angiography, which is increasingly being used to evaluate patients with chest pain symptoms. However, the efficiency of following up on incidentally detected PN is unknown.

Methods and results: We determined demographic and clinical characteristics of stable symptomatic patients referred for coronary CT angiography in whom incidentally detected PNs warranted follow-up. A validated lung cancer simulation model was populated with data from these patients, and clinical and economic consequences of follow-up per Fleischner guidelines versus no follow-up were simulated. Of the 3665 patients referred for coronary CT angiography, 591 (16%) had PNs requiring follow-up. The mean age of patients with PNs was 59±10 years; 66% were male; 67% had ever smoked; and 21% had obstructive coronary artery disease. The projected overall lung cancer incidence was 5.8% in these patients, but the majority died of coronary artery disease (38%) and other causes (57%). Follow-up of PNs was associated with a 4.6% relative reduction in cumulative lung cancer mortality (absolute mortality: follow-up, 4.33% versus non-follow-up, 4.54%), more downstream testing (follow-up, 2.34 CTs per patient versus non-follow-up, 1.01 CTs per patient), and an average increase in quality-adjusted life of 7 days. Costs per quality-adjusted life-year gained were $154 700 to follow up the entire cohort and $129 800 per quality-adjusted life-year when only smokers were included.

Conclusions: Follow-up of PNs incidentally detected in patients undergoing coronary CT angiography for chest pain evaluation is associated with a small reduction in lung cancer mortality. However, significant downstream testing contributes to limited efficiency, as demonstrated by a high cost per quality-adjusted life-year, especially in nonsmokers.

Keywords: comparative effectiveness research; computer simulation; coronary artery disease; cost-benefit analysis; health policy; pulmonary nodules, solitary; tomography, x-ray computed.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cardiac Imaging Techniques / economics*
  • Cardiac Imaging Techniques / methods
  • Chest Pain / diagnostic imaging
  • Chest Pain / economics
  • Comparative Effectiveness Research
  • Computer Simulation
  • Coronary Angiography / economics*
  • Coronary Angiography / methods
  • Coronary Artery Disease / diagnostic imaging
  • Coronary Artery Disease / economics*
  • Cost-Benefit Analysis
  • Female
  • Follow-Up Studies
  • Health Policy / economics
  • Humans
  • Incidental Findings
  • Lung Neoplasms / diagnostic imaging
  • Lung Neoplasms / economics*
  • Male
  • Middle Aged
  • Quality-Adjusted Life Years
  • Referral and Consultation / economics
  • Risk Assessment / economics
  • Solitary Pulmonary Nodule / diagnostic imaging
  • Solitary Pulmonary Nodule / economics*
  • Tomography, X-Ray Computed / economics*
  • Tomography, X-Ray Computed / methods