Psychological effects of colorectal cancer screening participation: a randomised trial

Abstract

Background: Cancer is one of the largest threats to peoples’ health, and participating in screening for cancer might therefore cause anxiety. Participation might cause worries in the population contributing to outweigh the benefits of screening. The present study aimed to investigate the long-term psychological reactions towards participation in colorectal cancer screening (CRC) in Norway. Methods: In a prospective, randomized trial (Bowel Cancer Screening in Norway (BCSN) – a pilot project) participants were invited to either Flexible Sigmoidoscopy (FS) screening, Faecal Immunochemical test (FIT) screening, or no screening (control group) (1:1:1). Together with the invitations in the intervention groups and one year following study participants received a Health-related Quality of Life (HRQOL) questionnaire (The ShortForm-12) and an anxiety and depression questionnaire (Hospital Anxiety and Depression Scale) to complete and return by mail. A control group was invited to complete the questionnaires only. Results: Number of invited individuals and questionnaire response rates were; 7270 (28%) in the FS arm, 7024 (35%) in the FIT arm, and 7650 (25%) in the control arm, respectively. Screening participation (FS and FIT combined) was associated with a statistically significant increase in proportion of cases of anxiety from baseline (HADS score ≥8 11.4%) to one year follow up(13.4%), p<.01, as well as in mean anxiety score from baseline (M=3.36) to follow up (M=3.49), p<.01. Anxiety in control participants did not increase significantly during follow up. Screening- and control-participants showed a similar decrease in HRQOL. Conclusion: The results indicate that screening participation might cause anxiety in some individuals.