[Effectiveness of screening colonoscopy in a community-based study]

Economic impact of disease prevention in a morbidity-based financing system: does prevention pay off for a statutory health insurance fund in Germany?

Preventable chronic diseases account for the greatest burden in the German health system and statutory health insurance (SHI) funds play a crucial role in implementing and financing prevention strategies. On the contrary, the morbidity-based scheme to distribute financial resources from the Central Reallocation Pool among the different sickness funds may counteract efforts of effective prevention from an economic perspective. We assessed financial impacts of prevention from a sickness funds perspective in a retrospective controlled study. Claims data of 6,247,275 persons were analyzed and outcomes between two propensity-matched groups (n = 852,048) of prevention users and non-users were compared in a 4-year follow-up. Using a difference-in-differences approach, we analyzed healthcare expenditures, the development of morbidity, financial transfers from the Central Reallocation Pool, and contribution margins. The group of prevention users develops less morbidity (incidences and disease aggravations) compared to the control group. Healthcare expenditures increase in both groups within 4 years, whereas the increase is lower for prevention users compared to non-users (€568.04 vs. €640.60, p < 0.0001). Taking morbidity-based financial transfers into account, the decrease in contribution margins is stronger for prevention users (- €188.44 vs. - €138.73, p < 0.0001). This study demonstrates an economic disincentive from a sickness funds' perspective. In the semi-competitive SHI market, sickness funds will be discouraged from effective prevention strategies if investments are not worth it financially. Their efforts and knowledge are, however, crucial for joint action to foster prevention over cure in the health system.

Critical Analysis of Markov Models Used for the Economic Evaluation of Colorectal Cancer Screening: A Systematic Review

BACKGROUND

The economic evaluation of colorectal cancer screening is challenging because of the need to model the underlying unobservable natural history of the disease.

OBJECTIVES

To describe the available Markov models and to critically analyze their main structural assumptions.

METHODS

A systematic search was performed in eight relevant databases (MEDLINE, Embase, Econlit, National Health Service Economic Evaluation Database, Health Economic Evaluations Database, Health Technology Assessment database, Cost-Effective Analysis Registry, and European Network of Health Economics Evaluation Databases), identifying 34 models that met the inclusion criteria. A comparative analysis of model structure and parameterization was conducted using two checklists and guidelines for cost-effectiveness screening models.

RESULTS

Two modeling techniques were identified. One strategy used a Markov model to reproduce the natural history of the disease and an overlaying model that reproduced the screening process, whereas the other used a single model to represent a screening program. Most of the studies included only adenoma-carcinoma sequences, a few included de novo cancer, and none included the serrated pathway. Parameterization of adenoma dwell time, sojourn time, and surveillance differed between studies, and there was a lack of validation and statistical calibration against local epidemiological data. Most of the studies analyzed failed to perform an adequate literature review and synthesis of diagnostic accuracy properties of the screening tests modeled.

CONCLUSIONS

Several strategies to model colorectal cancer screening have been developed, but many challenges remain to adequately represent the natural history of the disease and the screening process. Structural uncertainty analysis could be a useful strategy for understanding the impact of the assumptions of different models on cost-effectiveness results.

Prevalence of colorectal cancer and its precursor lesions in symptomatic and asymptomatic patients undergoing total colonoscopy: results of a large prospective, multicenter, controlled endoscopy study

BACKGROUND

Colorectal cancer (CRC) is the second most common cancer in Germany. Screening colonoscopies have been offered in Germany since 2002. However, validation of screening programs for CRC relies on estimates up to date.

OBJECTIVE

The aim of this study was to analyze the influence of the risk factor tumor-suspicious symptoms on the prevalence of CRC and its precursor lesions in patients at least 55 years of age undergoing colonoscopy in comparison with an age-matched and sex-matched control population undergoing screening colonoscopy.

DESIGN

Multicenter, prospective, controlled colonoscopy study.

SETTING

Integrated care program of 49 gastroenterological practices in collaboration with a health insurance company and the screening colonoscopy program in Hesse, Germany.

PATIENTS

In total, 1075 symptomatic and 5375 asymptomatic participants were matched for age and sex (1 : 5) from 1 October 2008 to 30 September 2010.

MAIN OUTCOME MEASUREMENTS

Detection of CRC and its precursor lesions.

RESULTS

Overall, the prevalence of CRC was significantly equivalent in both the symptomatic (n=13/1075, 1.21%) and the control group [n=55/5375, 1.02%, 95% confidence interval (CI) for the difference: [-0.46%, 0.83%], P=0.0002, equivalence test with δ=1.5%], respectively. Advanced adenomas were observed in significantly fewer symptomatic patients (61/1075, 5.67%) compared with 432/5375 matched asymptomatic screening participants (8.03%, 95% CI for the difference: [-3.98%, -0.74%], P=0.0094, difference test). Finally, polyps were found significantly less often in symptomatic patients (n=269/1075, 25.0%) than in matched screening participants (n=1807/5375, 33.6%, 95% CI for the difference: [-11.53%, -5.66%], P<0.0001, difference test).

CONCLUSION

The results underline the importance of screening the symptom-free population at least 55 years of age to prevent CRC.

Latest generation, wide-angle, high-definition colonoscopes increase adenoma detection rate

BACKGROUND & AIMS

Improvements to endoscopy imaging technologies might improve detection rates of colorectal cancer and patient outcomes. We compared the accuracy of the latest generation of endoscopes with older generation models in detection of colorectal adenomas.

METHODS

We compared data from 2 prospective screening colonoscopy studies (the Berlin Colonoscopy Project 6); each study lasted approximately 6 months and included the same 6 colonoscopists, who worked in private practice. Participants in group 1 (n = 1256) were all examined by using the latest generation of wide-angle, high-definition colonoscopes that were manufactured by the same company. Individuals in group 2 (n = 1400) were examined by endoscopists who used routine equipment (a mixture of endoscopes from different companies; none of those used to examine group 1). The adenoma detection rate was calculated on the basis of the number of all adenomas/number of all patients.

RESULTS

There were no differences in patient parameters or withdrawal time between groups (8.0 vs 8.2 minutes). The adenoma detection rate was significantly higher in group 1 (0.33) than in group 2 (0.27; P = .01); a greater number of patients with least 1 adenoma were identified in group 1 (22.1%) than in group 2 (18.2%; P = .01). A higher percentage of high-grade dysplastic adenomas were detected in group 1 (1.19%) than in group 2 (0.57%), but this difference was not statistically significant (P = .06).

CONCLUSIONS

The latest generation of wide-angle, high-definition colonoscopes improves rates of adenoma detection by 22%, compared with mixed, older technology endoscopes used in routine private practice. These findings might affect definitions of quality control parameters for colonoscopy screening for colorectal cancer.

Perspectives of colorectal cancer screening in Germany 2009

Adequate screening methods can decrease colorectal cancer (CRC) mortality. The guaiac test for fecal occult-blood (FOBT) is part of the German CRC Screening Program since 1970 and has evidence level Ia. In randomized multicenter-studies FOBT has an average sensitivity of 24% and decreases CRC mortality up to 30%. Immunological tests for human haemoglobin (iFOBT) show better performance characteristics than guaiac FOBT, with augmented sensitivity and specificity. However, the single tests show wide differences in diagnostic performance and iFOBT is not yet covered by insurance companies although it should replace the guaiac test for CRC screening. Visual colonoscopy, which was introduced to the German National Cancer Screening Program in 2002, is the gold standard for the diagnosis of colorectal neoplasia. From 2003 to 2007 more than 2.8 million examinations have been documented in Germany. The prevalence of adenomas is around 20% and of CRC about 0.7% to 1.0% of the screenings. Seventy percent of the carcinomas detected during screening are in an early stage (UICC I and II). Furthermore, screening colonoscopy is a cost saving procedure with a low complication rate (0.25% overall). Insurance companies save 216€ for each screening colonoscopy mainly by prevention of neoplasia due to polypectomy. In Germany, virtual colonography by computed tomography (CT) or magnetic resonance imaging still lacks standardization of the hard and software. In experienced centres the sensitivity for CRC and large polyps of CT colonography is comparable to colonoscopy but in meta-analyses the ranking is lower. New technologies like computer-aided colonoscopies with sheath or double balloon techniques are coming up as well as capsule colonoscopy, which sensitivity for large polyps is about 70%. Advised by his physician, the patient can choose his most acceptable examination method from this whole set of screening tools.

Is PillCam COLON capsule endoscopy ready for colorectal cancer screening? A prospective feasibility study in a community gastroenterology practice

OBJECTIVES

Colorectal cancer (CRC) screening with colonoscopy was introduced into the National Cancer Prevention Program in Germany in 2002. As compliance for screening is low (around 3% per year), colon capsule endoscopy (CCE) could be an alternative approach. In this study, feasibility and performance of CCE were evaluated in comparison with colonoscopy in ambulatory patients with special attention to a short colon transit time.

METHODS

CCE was prospectively tested in ambulatory patients enrolled for colonoscopy who presented for screening or with positive fecal occult blood test. Study subjects underwent colon preparation and ingested the capsule in the morning. Colonoscopy was performed after excretion of the capsule. Colonoscopy and CCE were performed by independent physicians who were blinded to the results.

RESULTS

In total, 38 patients were included. One patient was excluded because the capsule remained in the stomach during the entire period of examination. Another patient had limited time and the procedure had to be stopped when the capsule was still in the transverse colon. We therefore report the results of 36 patients (30 men and 6 women; mean age 56 years, range 23-73 years) who successfully completed CCE and the conventional colonoscopy examination. The capsule was excreted within 6 h in 84% of the patients (median transit time 4.5 h). If oral sodium phosphate was excluded from the preparation, the colon transit time increased to a median of 8.25 h. In total, 7 of 11 small polyps (<6 mm) detected by colonoscopy were identified by CCE. One small polyp detected by CCE was not identified by colonoscopy. In this series, no large polyps were found. One CRC was detected by both methods. The mean rates of colon cleanliness (range from 1=excellent to 4=poor) in the cecum (2.1), transverse colon (1.6), and in the descending colon (1.5) were significantly better than in the rectosigmoid colon (2.6), and the overall mean rate during colonoscopy was significantly better than during CCE. No adverse effects occurred.

CONCLUSIONS

CCE appears to be a promising new modality for colonic evaluation and may increase compliance with CRC screening. To achieve a short colon transit time, sodium phosphate seems to be a necessary adjunct during preparation. The short transit time is a prerequisite to abandon the delay mode of the capsule. With an undelayed PillCam COLON capsule, a "pan-enteric" examination of the gastrointestinal tract would be possible. Further studies are needed to improve the cleanliness, especially in the rectum and to evaluate the method as a potential screening tool.

Failure of screening or failure to screen? The screening behavior of patients with colorectal cancer in the Leipzig area

BACKGROUND

Colorectal cancer (CRC) is the second most common cancer-related cause of death in Germany. Screening for colorectal cancer is effective and is covered by statutory health insurance in Germany.

METHODS

The authors studied the screening behavior of patients with CRC in the Leipzig area in the 10 years before their diagnosis. The patients were asked to fill out a standardized questionnaire, and their primary care physicians were questioned, in order to determine what screening measures had been performed and why none had been performed in some cases.

RESULTS

212 patients with CRC were studied. In 175 (83%), cancer had been diagnosed after the appearance of symptoms ("symptomatic group"); in 37 (17%), it had been detected by screening ("screening group"). 51% of the overall patient group had undergone CRC screening in the 10 years before their diagnosis. A test of the stool for occult blood was the most common screening method but was generally not performed in conformity with guidelines. 25 patients (12%) had undergone a screening colonoscopy in the 10 years before their diagnosis; of these 25, 20 had undergone a screening colonoscopy in the 5 years before their diagnosis. The main reason why screening was not performed was ignorance of its availability.

CONCLUSIONS

This retrospective study revealed that, of 212 patients with CRC, most had not previously undergone CRC screening in conformity with guidelines. Better patient education by physicians may improve the effectiveness of screening. Appropriate screening measures include fecal occult blood testing and colonoscopy in conformity with guidelines.

Narrow-band versus white-light high definition television endoscopic imaging for screening colonoscopy: a prospective randomized trial

BACKGROUND & AIMS

Narrow-band imaging (NBI) has been implemented in gastrointestinal endoscopy to improve the contrast of endoluminal pathologic structures, one of the aims being to increase colonic adenoma detection. Previous studies from referral centers have yielded variable and conflicting results with regard to improvement in adenoma detection rates by using NBI. The present large randomized trial was designed to finally settle this issue.

METHODS

In a prospective study performed exclusively in a multicenter private practice setting involving 6 examiners with substantial lifetime experience (>10,000 colonoscopies), 1256 patients (men:women, 47%:53%; mean age, 64.4 y) were randomized to HDTV screening colonoscopy with either NBI or white-light imaging on instrument withdrawal. The primary outcome measure was the adenoma detection rate (ie, number of adenomas/total number of patients).

RESULTS

There was no difference between the 2 groups in terms of the general adenoma detection rate (0.32 vs 0.34), the total number of adenomas (200 vs 216), or in detection in subgroups of adenomas. This was despite a minimal, but significantly longer, withdrawal time in the NBI group (8.5 vs 7.9 min; P < .05). Only hyperplastic polyps were found more frequently in the NBI group (P = .03).

CONCLUSIONS

This large randomized trial in a homogeneous private practice screening setting could not show any objective advantage of the NBI technique over white-light high definition television imaging in terms of improved adenoma detection rate. Contrast enhancement therefore likely will not contribute to a reduction in adenoma miss rates among experienced colonoscopists.