Cost-effectiveness of an early awareness campaign for colorectal cancer

Transcription

1 Cost-effectiveness of an early awareness for colorectal cancer Sophie Whyte 1, Sue Harnan 1, Paul Tappenden 1, Mark Sculpher 2, Seb Hinde 2, Claire Mckenna 2 Policy Research Unit in Economic Evaluation of Health and Care Intervention (EEPRU) 1 School of Health and Related Research (ScHARR), University of Sheffield 2 Centre for Health Economics, University of York Contact: Sophie.Whyte@sheffield.ac.uk Project Aim Estimate cost effectiveness of an early awareness using data from the colorectal cancer early awareness piloted in the East of England and south west regions in January

2 Potential effects of an early awareness for colorectal cancer Early Awareness TV, radio, press, online, etc. Public awareness of signs and symptoms Increase in awareness? consultation GP consultations Increase? CRC screening Increase in uptake? screening referral GP referrals for suspected CRC Increase? Diagnosis of other lower GI conditions Increase? Cancer diagnoses Change in incidence/stage distribution? treatment Cancer mortality Decrease? lives save Scope of analysis The analysis captures: the direct of the, the any additional GP consultations/appointments in secondary care resulting from the benefits of the due to earlier diagnosis and any change in screening uptake. 2

3 Data from the pilot used in the modelling Data observed from pilot GP attendances 700 increase over 3 month period (532 increase if diarrhoea included as a symptom) Equivalent to 60,000-80,000 nationally. GP referrals CRC incidence CRC incidence stage distribution CRC screening uptake Cost of running 1,956 increase in referrals over 5 month period (+28%) 7-11% increase in incidence for 1 month Numbers too small to draw any conclusions No significant change which could be attributed to the Base case assumption in model 70,000 more attendances nationally over 3 month period Assumed 50% additional & 50% 17,519 additional referrals nationally Assumed 50% additional & 50% 10% increase in presentation rates for 1 month Campaign assumed to have the same proportional effect on presentation rates for each CRC stage. Assume screening uptake unaffected by Scenario analyses Assumed 90% additional & 10% Assumed 90% additional & 10% 5-20% magnitude 1-6 month duration Short term increase in incidence only consists of Dukes stages C & D Exploratory analysis undertaken 5 million 5 million - Methods Pilot data demonstrates short term impacts of the awareness. A mathematical model was used in combination with the pilot data to predict long term impacts of the on cancer incidence, mortality and. An existing mathematical model [1] was adapted (representing the CRC disease natural history, symptomatic presentation and the bowel cancer screening programme). [1] Re-appraisal of the options for colorectal cancer screening in England; Whyte S, Chilcott J, Halloran S, (Colorectal Disease, March 2012) 3

4 Model structure CRC natural history model CRC screening pathways Normal Epithelium Invited to screening LR adenomas Dead (non-crc) Screening test completed Do not attend screening HR adenomas Dukes A CRC Dukes A CRC clinical Positive screening result refer to follow up (colonoscopy) Negative screening test result / LR adenomas found Return to general screening population Dukes B CRC Dukes B CRC clinical Attend follow up Do not attend follow up Dukes C CRC Stage D CRC Dukes C CRC clinical Stage D CRC clinical Dead (CRC) No adenomas LR adenomas Transition estimated within model calibration Transition estimated directly from mortality data HR adenomas CRC Surveillance (annual/ 3-yearly colonoscopy) CRC treatment CRC=colorectal cancer, LR=low risk, HR=high risk Modelling methodology Four rates relating to symptomatic or chance presentation with Dukes A-D CRC. Baseline presentation rates reflect the England population from years 2004 to 2006 i.e. before screening commenced. The four transition probabilities are increased to result in an increase in incidence which matches the observed increase seen in the pilot. Assumption: causes a temporary change in the transition probabilities and that subsequently these probabilities will return to their pre- values. No data available on stage distribution of incidence. -> Assume that the extra incidence due to the awareness has the usual CRC stage distribution. 4

5 Results-Effectiveness The causes: Dukes stage A-C CRC presenting symptomatically Stage D CRC presenting symptomatically. CRC presenting symptomatically. Screen/surveillance detected CRC CRC specific deaths QALYs Results-Costs Overall the lead to increase in NHS Campaign running cost Screening (caused by a decrease in positives at screening since more CRC presents symptomatically) CRC treatment (1) CRC is presenting at younger ages which are associated with higher treatment. (2) A shift of cases from stage D to Dukes C and Dukes C CRC is associated with higher treatment than Dukes D. Costs associated with increased GP consultations and referrals (account for only a small proportion of total and are considerably less than the cost of the itself) 5

6 Model predictions For a CRC awareness resulting in a 10% increase in presentation rates for a period of one month Model predictions for the current population of England evaluated over a lifetime: Change compared to 'No awareness ' CRC incidence - symptomatic presentation Dukes Stage A 26 B 52 C 33 D -92 CRC incidence - symptomatic presentation TOTAL 20 CRC incidence screen/surveillance detected Dukes Stage A -0 B -1 C -2 D -2 CRC incidence - screening/surveillance detected TOTAL -5 CRC-specific deaths -66 Deaths with undiagnosed CRC -14 Total related to screening (discounted) - 3,407 Cancer management (inc. pathology) (discounted) 94,443 Cost of additional GP consultations/referrals (discounted) 855,716 Cost of awareness (discounted) 4,499,995 Total cost (discounted) 5,446,745 Total life years gained (discounted) 622 Total QALYs gained (discounted) 404 ICER 13,496 NMB 2,624,770 Modelling uncertainty: duration and magnitude of the change in presentation rates due to the Number of CRC deaths prevented 20% base case= 66 deaths prevented 15% 10% Increase in symptomatic presentation rate (%) 5% 0% Duration of increase in symptomatic presentation rate (months) 6

7 Priorities for future research Co-ordinate and maximise the evaluation and dissemination of efforts that have already been made to increase cancer awareness. comparison with non-intervention regions clear reporting of completeness of data and potential data limitations Information of importance for future modelling studies: duration of effect of effect of on CRC incidence effect of on emergency presentation rates effect of by age differential diagnoses associated with emergency presentation versus two-week wait referrals rates of diagnosis of other lower GI conditions with similar symptoms to CRC. 7