Incomplete small bowel capsule endoscopy: risk factors and cost-effectiveness of real-time viewing

Aims. International guidelines recommend real-time viewing (RTV) in capsule endoscopy for gastric emptying monitoring, yet it is often overlooked in clinical practice. We aim to assess risk factors for incomplete small bowel capsule endoscopy (SBCE) and evaluate the clinical relevance and cost-effectiveness of RTV implementation. Methods. We included consecutive SBCEs from 2013 to 2020. RTV was not applied per local protocol. We used multivariate logistic regression to identify risk factors for incomplete SBCE, including prolonged gastric transit time (GTT) and prolonged small bowel transit time (SBTT). Results. Analysing 858 SBCEs, we observed a completion rate of 94.6%. Prolonged GTT and SBTT were present in 4.9% and 18.2% of complete SBCEs, and in 13% (p=0.03) and 10.8% (p=0.24) of incomplete SBCEs, respectively. Only 0.7% (6 out of 858) had incomplete SBCE with prolonged GTT. In both univariate and multivariate analysis, a modifiable (prolonged GTT [OR 2.9; 95% CI 1.1-7.5]) and two unmodifiable risk factors (inpatient status [OR 2.3; 95% CI 1.1–4.5] and history of incomplete SBCE [OR 4.2; 95% CI 1.3-13.7]) were independently linked to higher incomplete SBCE rates. The pretest completion probability was 90.5% and 95.8% in patients with and without unmodifiable risk factors, respectively (p<0.01). The direct cost of systematic RTV adoption and prokinetics administration would be €5059, aiming to identify and treat each case of prolonged GTT associated with incomplete SBCE. Conclusions. Modern devices make incomplete SBCE rare, usually not tied to prolonged GTT. In a low-incidence scenario, widespread RTV use brings high costs and uncertain effectiveness.