Faecal occult blood testing for population health screening May 2004

Recommendations

Info

Is it safe? Adverse events associated with faecal occult blood tests FOBTs are non-invasive and therefore unlikely to cause adverse events. However, the use of FOBTs in a screening setting is likely to increase the number of colonoscopies, sigmoidoscopies and barium enemas performed in the screened population. Therefore, the increased numbers of adverse events associated with these procedures are important. The rates of adverse events associated with colonoscopy, sigmoidoscopy and double contrast barium enema (DCBE) are discussed below. Adverse events associated with colonoscopy, sigmoidoscopy and double contrast barium enema Colonoscopy is performed as a day-case procedure and generally requires sedation. In a study of colonoscopy data over a five-year period, diagnostic colonoscopy was associated with a complication rate of 0.14 per cent, compared with a rate of 1.8 per cent for therapeutic colonoscopy (Reiertsen et al 1987). In a 1997 review of six prospective studies it was estimated that around 1 in 1000 patients suffer perforation, 3 in 1000 suffer major haemorrhage and between 1 and 3 in 10,000 die as a result of colonoscopy (Winawer et al 1997). A 1989 review of nine studies of diagnostic colonoscopy gives a slightly higher figure of around 1.7 in 1000 patients suffering perforation and similar figures for haemorrhage and death (Habr-Gama and Waye 1989). The risk of perforation and haemorrhage increased with the performance of polypectomy. There are also other occasional serious complications associated with bowel preparation prior to colonoscopy or the use of sedation in conjunction with this procedure (National Health and Medical Research Council (NHMRC) 1999). Perforation rates associated with sigmoidoscopy are low and occur in fewer than 2 cases per 10,000 examinations (NHMRC 1999). Sedation is not generally used during sigmoidoscopy. DCBE is performed as an outpatient procedure. Sedation is not used. Serious complications are rare and include bowel perforation and cardiac complications. The complication rate of DCBE has been estimated at 3 per 10,000 tests, with a death rate of 3 in 100,000 tests (Winawer et al 1997). The Minnesota (US) randomised controlled trial (RCT) of FOBT screening for colorectal cancer (CRC) reported safety outcomes relevant to population health screening. This study utilised the Hemoccult test in combination with appropriate dietary restrictions. A perforation rate of 0.03% (4/12,246) and a rate of serious bleeding of 0.09% (11/12,246) were reported in association with colonoscopy (Mandel et al 1993). All four instances of perforation, and three of the eleven cases of serious bleeding, required surgery. The Nottingham (UK) FOBT trial reported complication rates in a smaller sample of colonoscopies. This study also used the Hemoccult test in combination with dietary restrictions. In this study, a rate of 0.5% complications of colonoscopy and no complications of DCBE from a total of 1778 subjects receiving follow-up was 16 Faecal occult blood testing
eported (Robinson et al 1999). Of the seven patients experiencing complications associated with colonoscopy (7/1474), six required surgery. There were no colonoscopyrelated deaths reported in either study. Psychiatric morbidity associated with colorectal cancer screening Concern has been expressed about the psychological impact of CRC screening, particularly for the group of participants that return false positives results. A recent publication by Parker et al (2002) investigated the psychiatric morbidity associated with CRC screening in an RCT. The RCT aimed to determine: (a) whether the offer of faecal occult blood testing caused increased, sustained anxiety; (b) whether the existence of psychiatric morbidity was a factor in the decision to accept or refuse screening; and (c) the anxiety levels of participants returning positive FOBTs at screening, clinical investigation and follow up. The study found that participation in a faecal occult blood screening program for CRC did not cause sustained anxiety or psychiatric morbidity. The study also showed that a positive screening result caused short-term anxiety in most subjects, but this returned to a lower level one month after clinical investigation (anxiety was measured on the Spielberger anxiety inventory). Similarly, the study showed no sustained anxiety in participants returning false positive results. This is important, as it has been suggested that the high false positive rate in faecal occult blood screening will undermine public confidence in the screening programs. In fact, when questioned one month after investigation, 85 per cent of participants stated that they would accept screening if it was offered again in 2 years. Another trial that investigated the experiences of participants receiving false positive results from CRC screening found that 26 per cent were quite distressed or very distressed from the initial false positive result (Mant et al 1990). The remaining 74 per cent of patients were slightly distressed or not at all distressed regarding the false positive FOBT result. A total of 98.1 per cent of the participants returning false positive results in this study believed that it was worthwhile having the test. This is an important issue; however, exploration of this in detail would required a dedicated systematic review and exploration via a cost-effectiveness comparison incorporating quality-of-life measures, which is beyond the scope of this review. Safety data reported in the FOBT studies The head-to-head studies examining the relative performance of different FOBTs identified in this assessment did not report any safety data. Faecal occult blood testing 17
Page 1 and 2: Faecal occult blood testing for pop
Page 3 and 4: Contents Executive summary.........
Page 5 and 6: Tables Table 1 Hierarchy of evidenc
Page 7: Figures Figure 1 Reasons for exclus
Page 10 and 11: BM-Test Colon Albumin. HemeSelect a
Page 12 and 13: The head-to-head studies examining
Page 14 and 15: sensitivity between tests contains
Page 17 and 18: Introduction The Medical Services A
Page 19 and 20: The guaiac FOBTs include brand name
Page 21 and 22: Classification of CRC may be by one
Page 23 and 24: Current reimbursement arrangement F
Page 25 and 26: Searches of the following secondary
Page 27 and 28: Identified by the search (n = 1214)
Page 29 and 30: Expert advice An advisory panel wit
Page 31: Trial Trial design Reviewed for eff
Page 35 and 36: unacceptable and unethical to subje
Page 37 and 38: Long-term follow-up Randomisation/
Page 39 and 40: Three different methods are used to
Page 41 and 42: • β j is a fixed effect which is
Page 43 and 44: Table 4 Meta-analyses of sensitivit
Page 45 and 46: Relative true positive rate and rel
Page 47 and 48: Table 7 Meta-analyses of relative F
Page 49 and 50: subject to verification bias due to
Page 51 and 52: The literature on FOBT screening fo
Page 53 and 54: Figure 3 Screening pathway used in
Page 55 and 56: Table 10 Prevalence used for indivi
Page 57 and 58: Table 15 and Table 16 outline the c
Page 59 and 60: Relevant sensitivity and specificit
Page 61 and 62: Table 22 Detection rates associated
Page 63 and 64: Following diagnosis of CRC, patient
Page 65 and 66: In the case of Hemoccult Sensa, col
Page 67 and 68: Of the two tests, Hemoccult Sensa d
Page 69 and 70: Table 31 Life-expectancy from the b
Page 71 and 72: • The frequency of screening has
Page 73 and 74: Additionally, for both FOBTs, incre
Page 75 and 76: screening are higher, the differenc
Page 77 and 78: Conclusions Safety Faecal occult bl
Page 79 and 80: The incremental cost per life-year
Page 81: Summary of outcomes The Medical Ser
Page 84 and 85:
Professor Bryant Stokes Neurologica
Page 86 and 87:
Professor Graeme Young MBBS MD FRAC
Page 88 and 89:
Specificity carcinoma Sensitivity c
Page 90 and 91:
Appendix D Literature searches Medl
Page 92 and 93:
Search history Results 26 hemeselec
Page 94 and 95:
10. Bech K, Kronborg O, Fenger C (1
Page 96 and 97:
33. Foliente RL, Wise GR, Collen MJ
Page 98 and 99:
56. Hart AR, Barone TL, Gay SP, Ing
Page 100 and 101:
79. Kronborg O, Fenger C, Olsen J,
Page 102 and 103:
102. Lynch NM, McHutchison JG, Youn
Page 104 and 105:
125. Nakama H, Fattah A, Zhang B, U
Page 106 and 107:
148. Rasmussen M, Fenger C, Kronbor
Page 108 and 109:
169. Scholefield JH, Moss S, Sufi F
Page 110 and 111:
192. Walker AR, Whynes DK, Hardcast
Page 112 and 113:
Appendix F Positive predictive valu
Page 114 and 115:
Table 42 Meta-analyses of PPV for c
Page 116 and 117:
Table 43 Meta-analyses of PPV for n
Page 118 and 119:
Appendix G Diagnostic odds ratios A
Page 120 and 121:
Figure 10 Summary receiver-operatin
Page 122 and 123:
Appendix I Participation in FOBT sc
Page 124 and 125:
Appendix J Relative cost-effectiven
Page 126 and 127:
Number detected by screening or sym
Page 128 and 129:
Appendix K Sensitivity analysis of
Page 130 and 131:
Abbreviations AACR Australasian Ass
Page 132 and 133:
References Aisawa T, Saito H, Kawag
Page 134 and 135:
Hardcastle JD, Armitage NC, Chamber
Page 136 and 137:
Rae AJ, Cleator IGM (1994), The two
Page 138:
Young GP, St John DJB, Winawer SJ,
show all

Faecal occult blood testing for population health screening May 2004

Create successful ePaper yourself

Delete template?

Save as template?