Anxiety and colonoscopy: approaches to minimise anxiety and its adverse effects
Potential adverse outcomes associated with anxiety[edit source]
While the literature on colonoscopy is extensive, few studies explore its association with anxiety. In a study investigating the procedural experience of patients undergoing endoscopic procedures, researchers assessed 88 consecutive patients undergoing colonoscopy (n = 55) or gastroscopy (n = 33) 1 week prior to the investigation, while awaiting procedure commencement and 24-72 hours after recovering from sedation post procedure. Before the procedure, the colonoscopy group anticipated significantly more pain and had significantly lower pre-procedural acceptance than the gastroscopy group. However, the colonoscopy group reported lower pain and significant decreases in endoscopy concerns and anxiety after the procedure. Despite this, their acceptance of the procedure did not significantly improve after the procedure, while there was near-universal acceptance of the test in the gastroscopy group. Anticipated pain was the strongest predictor of pre-test acceptance of colonoscopy. The concern of pain associated with colonoscopy needs to be addressed by the practitioner.
Target groups for interventions to minimise anxiety[edit source]
The evidence suggests two target groups for interventions to minimise anxiety: those with low socioeconomic status (SES) and those who generally tend to be anxious. In addition, women have been identified as more anxious than men in intervention research studies (see Overview of evidence section below)
Socioeconomic status[edit source]
Researchers have observed differences according to SES in coping with stressful medical procedures.
In a large participant subgroup (n = 3535) from the UK Flexible Sigmoidoscopy Trial, anxiety and worry about bowel cancer pre-screening were higher in lower SES participants. Their worry and anxiety reduced after screening, but not to a significantly greater extent than the high-SES group. However, the low-SES subgroup did report more positive psychological consequences of screening in the post-flexible sigmoidoscopy sample (n = 40,534), with an SES gradient for anxiety but not distress measures.
While patients in this study underwent screening flexible sigmoidoscopy, the results are likely to be generalisable to those undergoing surveillance colonoscopy, where there are also likely to be concerns about bowel cancer.
Accuracy of physician estimates of anxiety[edit source]
'Trait anxiety' is the tendency to experience anxiety and is considered a stable personality trait. 'State anxiety' is temporary discomfort when feeling threatened by a situation. State anxiety, but not trait anxiety, was found to be moderately increased in patients undergoing outpatient diagnostic endoscopy in a US consecutive case series. State anxiety about the procedure did not differ by age, sex, source of referral, procedure type or perceived procedural knowledge. Thus, people who tended to be anxious overall were also more anxious immediately before the procedure. The authors notably found that physician estimates of patient anxiety were not significantly associated with either procedural state anxiety or changes in state anxiety between baseline and the procedure, and speculated that physician estimates are unrelated due to the increases in state anxiety being small.
Overview of evidence (non-systematic literature review)[edit source]
No systematic reviews were undertaken for this topic. Practice points were based on selected evidence and guidelines (see Guideline development process).
Anxiety level before and during colonoscopy[edit source]
Overall, the evidence suggests that 16–20% of people undergoing colonoscopy have severe anxiety, usually related to pain and discomfort. A cross-sectional study examined the possible relationship between state (i.e., situational) and trait (i.e., stable) anxiety in 52 gastroscopy and 46 colonoscopy outpatients. The researchers observed a small but statistically significant increase in state anxiety before elective upper gastroscopy and colonoscopy, but no changes in trait anxiety. Females had higher anxiety levels in both procedures. Overall, anxiety levels were not related to type of procedure.
A service evaluation based in the UK was conducted to determine patients’ (n = 216) attitudes, preferences and expectations for day-case colonoscopy. Patients attending for elective colonoscopy completed and returned a composite patient pre-procedure questionnaire comprised of Likert scale questions examining patient levels of anxiety pre-procedure and the causes of anxiety, demographic characteristics, previous colonoscopy experience, preferred staff roles and patient preferences for a single-sex colonoscopy department. A 15-point preference (ranking) scale was also included which addressed the domains of endoscopy care that were considered most important to least important as contributing to satisfactory experience. Additionally, a sample of 19 patients from the study cohort completed the 15-point ranking questionnaire post-procedure. Pre-procedure, 43.5% of patients reported none or mild anxiety, 40.3% reported moderate anxiety and 16.2% reported severe or very severe anxiety (p = 0.066). The anticipation of pain (40.8%), the nature of the results (37.3%) and potential complications and sedation (21.9%) were reported as the main sources of their anxiety. Interestingly, similar levels of moderate to severe anxiety were reported irrespective of previous experience of having a colonoscopy (59.8% versus 52.9%, p = 0.3). However, patients who reported having previous experience of pain or discomfort during a colonoscopy (n = 64) were more likely to report moderate to severe anxiety (73.4% versus 36.5%, p<0.01), particularly related to procedure-associated pain (51.6% versus 19.2%, p<0.01) and expectation of severe or moderate pain (50% versus 19.2%, p = 0.01). Hence, whilst the use of sedation and analgesia reduce the experience of pain during a colonoscopy, pain and discomfort are often identified as factors contributing to unwillingness to return for a repeat procedure, with associated increased anxiety prior to future examinations. This is clearly relevant to patients whose screening or surveillance entails multiple colonoscopies.
A sex- and age-matched case-control, cross-sectional study of 100 patients with inflammatory bowel disease (IBD) and 100 patients without IBD (control group) examined whether the quality and tolerance of bowel preparation was associated with anxiety levels immediately prior to colonoscopy. Before their procedure, patients completed a questionnaire consisting of the Hospital Anxiety and Depression Scale (HADS-A/HADS-D), Visceral Sensitivity Index, State Trait Anxiety Inventory (STAI-S) and self-assessed their bowel preparation, and abdominal pain and nausea during it. Endoscopist-reported measures included the Mayo score, Harvey Bradshaw Index, simple endoscopic score for Crohn’s disease, and the Boston Bowel Preparation Scale (BBPS). A multiple linear regression model identified that nausea (p = 0.0071), abdominal pain during bowel preparation (p = 0.0029) and a lower number of previous colonoscopies (p = 0.032) were independently associated with pre-procedure anxiety (assessed by STAI-S), after controlling for age, sex and endoscopist-rated quality of bowel preparation (on the BBPS). Based on these findings, the authors suggested that taking measures to reduce anxiety could improve tolerance of bowel preparation and colonoscopy.
In some situations, patients may undergo colonoscopy without clinical consultation with an endoscopist before the day of the procedure. An observational study of 409 colonoscopy-naïve patients compared the pre-endoscopy information-seeking behaviours and levels of anxiety about the procedure (using a single question using a 10-item rating scale) of patients who did not receive clinical consultation (direct group; 34% of total sample) with those of patients who had received a pre-procedure consultation with the endoscopist (consult group). The study found no differences in pre-procedure anxiety levels between the direct group (mean 4.7; 95% confidence interval [CI]: 4.3–5.2) and the consult group (5.0; 95% CI: 4.6–5.3), but found that undergoing a colonoscopy for symptoms rather than for screening was associated with greater anxiety. Furthermore, 20% of participants overall reported high pre-procedure anxiety, suggesting a need for measures to reduce anxiety including providing detailed information about the procedure.
A prospective qualitative study of 13 patients in Australia examined the effect of colonoscopies on patients’ anxiety about their initial colonoscopy. The researchers interviewed patients 1 week before and 1 week, 2 weeks and 12 months after their colonoscopy. Participants reported that the procedure was associated with stigma, and that discussing it was stressful, embarrassing and anxiety-provoking. The researchers reported that contributors to patient anxiety included irrational expectations of the procedure, limited perceptions of control and power imbalances with doctors. Prior to procedures, anxiety was elicited by fear of a serious diagnosis, while an unclear or functional diagnosis seemingly increased anxiety after the procedure. The authors noted that anticipating the preparation before the procedure was reportedly important to manage anxiety during this stage. The authors advocated for increased shared decision-making as part of a shift towards the biopsychosocial model of healthcare to reduce patient anxiety. Notably, they recommended developing and using neutral language for colonoscopy procedures to reduce the stigma of colonoscopies and bowel health issues.
A 2013 systematic review examined patients’ experiences of colonoscopy in the screening context. From 56 included studies, most patients reported that the most burdensome aspect of a colonoscopy was bowel preparation. Patients also reported anxiety, pain anticipation and feeling embarrassed and vulnerable. Obstacles to screening colonoscopies included inadequate knowledge of the procedure and fear of finding cancer. The reviewers found that physician recommendations, family history, knowing a person with cancer and perceiving the test to be accurate motivated patients to have a colonoscopy.
Anxiety levels in children and adolescents[edit source]
While colonoscopy is most frequently performed on adults, it may be used in the diagnostic evaluation of children and adolescents with colonic disease. Adolescents with IBD will usually require colonoscopy from time to time.
A study designed to compare adolescents aged 10–18 years with either IBD or functional gastrointestinal disease (FGID) undergoing their first colonoscopy recorded the levels of pain or anxiety that they experienced. These levels were assessed by means of a questionnaire recorded immediately before the procedure and a second questionnaire 48 hours later. While no differences in anxiety were reported, it was noted that children with IBD at the time of colonoscopy experienced higher levels of anxiety accompanied by higher pain scores. Adolescents with FGID experience common pain symptoms during colonoscopy and may describe more post-colonoscopic pain than those with IBD. It was concluded that anxiety is associated with severity of pain after colonoscopy in children with IBD, while not observed to be a factor in children with FGID.
Reducing anxiety about colonoscopy[edit source]
Studies have investigated the efficacy of information in various formats, aromatherapy, and audio or visual distraction in reducing anxiety, increasing satisfaction and reducing pain, with variable outcomes.
Providing information[edit source]
An Australian study assessed the response of 80 patients to information consistent with their coping style. The researchers classified patients according to their coping style as either information seekers or information avoiders. The researchers administered an information intervention that included a general description of colonoscopy and procedural events like the potential complications of and instructions about preparing for the procedure. This information was provided orally and in writing. There was also a sensory information condition that described in depth what the patient might see, hear, or feel during each part of the procedure, such as during hospital admission procedures, in the endoscopy room, during intravenous line insertion, when affected by intravenous sedation, and during the colonoscopy and recovery. This information was also provided orally and in writing.
The researchers found that information seekers receiving sensory information (more information overall) self-reported less anxiety than information seekers receiving information on the procedure. In contrast, information avoiders receiving procedural information (less information overall) self-reported lower anxiety than avoiders receiving sensory information. Those groups who received the amount of information consistent with their preferences also reported more satisfaction with the intervention, were observed to experience less pain and exited recovery 12–16 minutes earlier. However, there were no differences on perceptions of pain or dosages of sedative medications.
A cross-sectional, mixed-methods study explored the experience of anxiety in colonoscopy outpatients by evaluating whether any differences in state anxiety existed between pre- and post-colonoscopy patients, and whether problem-focused, emotion-focused, and maladaptive coping styles were significantly associated with this anxiety. The researchers recruited 26 pre-procedure participants and 24 post-procedure participants, and found a strong, positive relationship between maladaptive coping and state anxiety in the entire sample. This relationship also existed in both pre-procedure and post-procedure samples. The interviews indicated that clinicians and endoscopy nurses needed to be aware that some patients do not correctly process information about colonoscopy; specifically, the knowledge that they may be conscious or experience pain during the procedure. The study authors recommended that clinicians ensure that patients understand the standard practice of the hospital, and that more attention be given to pain management as it may not be adequate during conscious sedation.
A randomised controlled trial (RCT) explored the ability of an information intervention provided before clinical procedures to improve procedural knowledge and consequently reduce anxiety related to it. The investigators randomly assigned patients to either viewing or not viewing an information video before colonoscopy. The study enlisted 150 patients; 72 video-watchers and 78 non-video-watchers. The groups were generally similar in terms of age, sex, education levels and initial anxiety scores, but female patients had higher baseline anxiety scores than male patients. Patients who had previously had colonoscopies had lower baseline anxiety scores than those with no previous experience. The authors found that patients who watched the video reported significantly less anxiety than control group participants. The intervention group reported significantly more knowledge on items assessing the purpose, details and potential complications of colonoscopies. A commentary on the RCT argued that the intervention may be cost-effective by reducing cost of sedation and post-operative recovery time, although it does not appear that cost-effectiveness has been evaluated for this intervention.
In a study of 201 patients undergoing colonoscopy, patients were randomised into three groups: those provided with pre-procedure information by video plus discussion, those provided with video alone and and those provided with discussion alone. Patients in both groups who viewed the videos had significantly higher scores on knowledge than those in the discussion alone group, but there were no statistically significant differences in knowledge scores between the two groups viewing the video. Increased understanding of the benefits and risks of colonoscopy was not associated with increases in anxiety.
Another RCT of 162 colonoscopy patients included an information video as part of pre-procedure preparation, with control patients not watching the video. The investigators found no differences between the groups on situational, pain ratings, procedure tolerability or willingness to have future colonoscopies. All staff rated outcomes in the two groups equally. The two groups did not differ in midazolam dosages, but patients in the video group used significantly higher fentanyl doses. Women had significantly higher situational anxiety ratings, and also reported less satisfaction with the procedure and more pain from it.
A non-RCT investigated the effects of written and oral information versus oral information alone on pre-colonoscopy anxiety. Patients in group one (n = 51) received written and oral information and group two (n = 53) received only oral information. The written information discussed preparation, the process of colonoscopy and potential issues needing attention following the procedure. The oral information was identical to the written information. Patients completed questionnaires 24 hours before and on the day of the colonoscopy. State anxiety scores after the colonoscopy lowered, but this was not statistically significant and there were no between-group differences at either time point. The study author suggested that written information potentially increased anxiety in patients with high baseline trait anxiety, as too much detailed information made them more aware of the risks and insertion process. Furthermore, information was provided to patients a day before their procedure, which may not have allowed sufficient time for patients to adequately process the information.
Another RCT examined the impact of using information videos before colonoscopy on patient satisfaction and anxiety. The authors recruited 227 patients from an endoscopy unit and randomly assigned them to either the video group (n = 124) or verbal group (n = 130). Patients in the video group viewed a 10-minute video about the colonoscopy procedure and had their questions about the procedure answered, while patients in the verbal group listened to a text version of the video spoken by physicians uninvolved in the colonoscopy procedure and subsequently also had their questions answered. Low state anxiety levels and communication by video were significantly associated with 'communication success', considered by the authors to have been achieved where patients indicated post-procedure that the procedure was similar to or better than they had been told. The state anxiety levels were notably significantly higher in women than men at baseline.
Note: Clinicians should also follow the Clinical Care Standards that apply to the preparation of patients for procedures, including informed consent (see Australian Commission on Safety and Quality in Health Care Colonoscopy Clinical Care Standards).
An RCT of the effect of aromatherapy on alleviating anxiety, stress and physiological parameters of colonoscopy randomised 27 patients into groups inhaling neroli oil (experimental group, n = 14) or sunflower oil (control group, n = 13). The researchers found no significant differences in state procedural anxiety or procedural pain scores before and after aromatherapy, although neroli oil was significantly more effective in reducing systolic blood pressure than sunflower oil.
Audiovisual distraction strategies[edit source]
An RCT investigated the effects of visual and audiovisual distraction during colonoscopy on pain, anxiety, and procedure tolerance in 180 patients. Participants were randomly allocated to one of three groups: Group A (n = 60) received visual distraction (DVD with no sound and earphones on), Group B (n = 60) received audio-visual distraction (DVD with sound and earphones on), and Group C (n = 60) received routine care. Before the procedure, patients were permitted to select their preferred DVD (e.g., landscape scenery, animation, comedy, Chinese Kung Fu). The groups did not differ significantly on state and trait anxiety before the procedure. The researchers observed lower pain scores in the visual and audio-visual distraction groups relative to the control group, but not to a statistically significant extent. Patients in the visual and audio-visual distraction groups reported more willingness to repeat the procedure.
An endoscopist-blinded RCT in Japan assessed the intervention of relaxing visual distraction on patient pain, anxiety and satisfaction during colonoscopy. Patients (n = 60) were randomly allocated to one of two groups, with the first group (n = 28) viewing a silent movie wearing a head-mounted display and the second group (n = 29) wearing only the display. Patients in the first group reported significantly higher median post-procedural satisfaction levels than patients in the second group. In patients who had anxiety scores of 50 or higher before the procedure, the anxiety and pain scores during the procedure were significantly lower in the group receiving the visual distraction intervention.
Anaesthesia and sedation technique[edit source]
Multiple guidelines strongly recommend administering medication for endoscopic procedures and, in Australia, most patients receive sedation for their colonoscopies. Frequently used approaches include deep sedation induced by propofol, or conscious sedation induced by combining benzodiapines and opioids. Because of the deeper level of sedation/anaesthesia achieved with propofol, pain during the procedure should be minimal but there have been no studies of these two commonly used sedative regimens comparing their effects on anxiety or on anxiety associated with future colonoscopy.
An Australian RCT compared an alternative approach using methoxyflurane administered via portable inhaler (Penthrox) with intravenous midazolam and fentanyl, and showed no differences between the groups in pain scores or nervousness. It should be noted that Penthrox may not be suitable for all patients, particularly those with significant anxiety disorders or visceral hypersensitivity, even though it has the potential safety advantage of lack of respiratory depression.
A prospective study investigated the effects of pre-procedure anxiety on patient sedative requirements in 135 patients undergoing sedation for colonoscopy. Before the procedure, intravenous propofol was administered until patients exhibited no responses to verbal commands (loss of consciousness). Colonoscopy then began. The endoscopist assessed procedural time, spasm score and difficulty score for colonoscopy immediately after the procedure. The researchers observed no association between pre-procedural anxiety and sedative requirements for deep sedation in patients receiving colonoscopies, suggesting that the two are unrelated.
A single-blind RCT was used to assess the efficacy of music for patients undergoing colonoscopy. In this study, 109 patients were randomised and fitted with mute or music-delivery headphones. Clinicians were blinded to the trial and sedation was provided if requested. Primary outcome was the measurement of pain and secondary endpoints were recorded as need for sedation, patient satisfaction and willingness to repeat the procedure. Those wearing music headphones recorded statistically significant reduction in pain and in the proportion of patients requiring sedation. Clinicians perceived less difficulty and multivariate analysis confirmed a significant beneficial effect of music. The introduction of music during colonoscopy significantly reduces discomfort.
A meta-analysis of RCTs on the effect of music on patients undergoing colonoscopy, assessed procedure time, dose of sedation, pain scores and willingness to repeat the procedure in the future. Eight studies met the criteria and observed that patients’ overall experience was statistically significantly improved when music was used during the procedure. There were significant differences in pain scores, sedation levels, procedure time and willingness to repeat the procedure. The investigators concluded that music can 'improve patients’ overall experience with colonoscopy'.
In another randomised study in a US veterans' gastrointestinal diagnostic facility, 198 patients were randomised. Ninety-eight (98) comprised a control group, who had 25 minutes of quiet time before endoscopy while the study group (100) had music selected by the investigators, who were nurses, for 25 minutes before having endoscopy. All were evaluated by the STAI-S. Both groups experienced reduced anxiety scores but, after controlling for trait anxiety, there was a statistically different outcome between the groups, with those listening to music having a greater reduction in anxiety. It is suggested that music, a non-invasive nursing intervention may reduce anxiety if provided prior to gastrointestinal investigative procedures.
Practice points[edit source]
Endoscopists should aim to control pain and discomfort during a colonoscopy procedure in order to reduce patient anxiety.
Physicians should be able to provide accurate and relevant information about colonoscopy for patients who are undergoing open access colonoscopy (without prior consultation with an endoscopist).
The use of neutral language around colonoscopy may be useful in order to break down the stigma and taboo surrounding the procedure and bowel health issues.
Clinicians should ensure that patients understand the standard practice and convey information about the procedure as clearly as possible (e.g., whether they will be conscious, whether they will experience pain, etc.).
Note: Clinicians should also follow the Clinical Care Standards that apply to the preparation of patients for procedures, including informed consent (see Australian Commission on Safety and Quality in Health Care Colonoscopy Clinical Care Standards).
Music provided to patients prior to and during colonoscopy may reduce their discomfort.
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