Reduced pain during screening colonoscopy with an ultrathin colonoscope: a randomized controlled trial

Background and study aims: Screening colonoscopy for colorectal cancer (CRC) is recommended in several countries, but uptake rates are often low. Fear of pain and also time-consuming costly sedation are barriers for colonoscopy, and thus development of colonoscopy equipment that decreases patient discomfort is worthwhile. This randomized controlled trial investigated the performance of an ultrathin colonoscope in CRC screening. Patients and methods: Consecutive participants in a colonoscopy screening trial were randomized to examination with an ultrathin prototype colonoscope or a standard colonoscope. The main outcome measure was pain during the examination. Participants rated pain (no, slight, moderate, severe) using a validated questionnaire. Results: From 187 enrolled participants (80 women [43%]), 162 (87%) responded to the questionnaire. The study groups were similar regarding baseline characteristics. Pain scores were significantly lower in the prototype instrument group compared with the standard group (78% vs. 29% of patients with no pain in prototype and standard groups, respectively; odds ratio [OR] 0.11; 95% confidence interval [CI] 0.06-0.23; P<0.001). Cecal intubation rate was 98% in the prototype group and 92% in the standard group (P=0.085). Sedation was used in 2% and 7% in the prototype and standard groups respectively (P=0.12). Adenoma detection rate was 13% in the prototype group vs. 24% in the standard group (P=0.052). Conclusion: The new ultrathin Olympus colonoscope decreases patient pain during screening colonoscopy. This feature may improve uptake and patient satisfaction in screening colonoscopy. Further study is needed to evaluate the lower adenoma detection rate.