An efficient strategy for evaluating new non-invasive screening tests for colorectal cancer: the guiding principles

OBJECTIVE

New screening tests for colorectal cancer (CRC) are rapidly emerging. Conducting trials with mortality reduction as the end point supporting their adoption is challenging. We re-examined the principles underlying evaluation of new non-invasive tests in view of technological developments and identification of new biomarkers.

DESIGN

A formal consensus approach involving a multidisciplinary expert panel revised eight previously established principles.

RESULTS

Twelve newly stated principles emerged. Effectiveness of a new test can be evaluated by comparison with a proven comparator non-invasive test. The faecal immunochemical test is now considered the appropriate comparator, while colonoscopy remains the diagnostic standard. For a new test to be able to meet differing screening goals and regulatory requirements, flexibility to adjust its positivity threshold is desirable. A rigorous and efficient four-phased approach is proposed, commencing with small studies assessing the test's ability to discriminate between CRC and non-cancer states (phase I), followed by prospective estimation of accuracy across the continuum of neoplastic lesions in neoplasia-enriched populations (phase II). If these show promise, a provisional test positivity threshold is set before evaluation in typical screening populations. Phase III prospective studies determine single round intention-to-screen programme outcomes and confirm the test positivity threshold. Phase IV studies involve evaluation over repeated screening rounds with monitoring for missed lesions. Phases III and IV findings will provide the real-world data required to model test impact on CRC mortality and incidence.

CONCLUSION

New non-invasive tests can be efficiently evaluated by a rigorous phased comparative approach, generating data from unbiased populations that inform predictions of their health impact.

Recommendations on Surveillance and Management of Biallelic Mismatch Repair Deficiency (BMMRD) Syndrome: A Consensus Statement by the US Multi-Society Task Force on Colorectal Cancer

The US Multi-Society Task Force on Colorectal Cancer, with invited experts, developed a consensus statement and recommendations to assist health care providers with appropriate management of patients with biallelic mismatch repair deficiency (BMMRD) syndrome, also called constitutional mismatch repair deficiency syndrome. This position paper outlines what is known about BMMRD, the unique genetic and clinical aspects of the disease, and reviews the current management approaches to this disorder. This article represents a starting point from which diagnostic and management decisions can undergo rigorous testing for efficacy. There is a lack of strong evidence and a requirement for further research. Nevertheless, providers need direction on how to recognize and care for BMMRD patients today. In addition to identifying areas of research, this article provides guidance for surveillance and management. The major challenge is that BMMRD is rare, limiting the ability to accumulate unbiased data and develop controlled prospective trials. The formation of effective international consortia that collaborate and share data is proposed to accelerate our understanding of this disease.

Recommendations on Surveillance and Management of Biallelic Mismatch Repair Deficiency (BMMRD) Syndrome: A Consensus Statement by the US Multi-Society Task Force on Colorectal Cancer

The US Multi-Society Task Force on Colorectal Cancer, with invited experts, developed a consensus statement and recommendations to assist health care providers with appropriate management of patients with biallelic mismatch repair deficiency (BMMRD) syndrome, also called constitutional mismatch repair deficiency syndrome. This position paper outlines what is known about BMMRD, the unique genetic and clinical aspects of the disease, and reviews the current management approaches to this disorder. This article represents a starting point from which diagnostic and management decisions can undergo rigorous testing for efficacy. There is a lack of strong evidence and a requirement for further research. Nevertheless, providers need direction on how to recognize and care for BMMRD patients today. In addition to identifying areas of research, this article provides guidance for surveillance and management. The major challenge is that BMMRD is rare, limiting the ability to accumulate unbiased data and develop controlled prospective trials. The formation of effective international consortia that collaborate and share data is proposed to accelerate our understanding of this disease.

The American Society for Gastrointestinal Endoscopy PIVI (Preservation and Incorporation of Valuable Endoscopic Innovations) on real-time endoscopic assessment of the histology of diminutive colorectal polyps

The PIVI (Preservation and Incorporation of Valuable endoscopic Innovations) initiative is an ASGE program whose objectives are to identify important clinical questions related to endoscopy and to establish a priori diagnostic and/or therapeutic thresholds for endoscopic technologies designed to resolve these clinical questions. Additionally, PIVIs may also outline the data and or the research study design required for proving an established threshold is met. Once endoscopic technologies meet an established PIVI threshold, those technologies are appropriate to incorporate into clinical practice presuming the appropriate training in that endoscopic technology has been achieved. The ASGE encourages and supports the appropriate use of technologies that meet its established PIVI thresholds. The PIVI initiative was developed primarily to direct endoscopic technology development toward resolving important clinical issues in endoscopy. The PIVI initiative is also designed to minimize the possibility that potentially valuable innovations are prematurely abandoned due to lack of utilization and to avoid widespread use of an endoscopic technology before clinical studies documenting their effectiveness have been performed. The following document, or PIVI, is one of a series of statements defining the diagnostic or therapeutic threshold that must be met for a technique or device to become considered appropriate for incorporation into clinical practice. It is also meant to serve as a guide for researchers or those seeking to develop technologies that are designed to improve digestive health outcomes. An ad hoc committee under the auspices of the existing ASGE Technology and Standards of Practice Committees Chairs develops PIVIs. An expert in the subject area chairs the PIVI, with additional committee members chosen for their individual expertise. In preparing this document, evidence-based methodology was employed, using a MEDLINE and PubMed literature search to identify pertinent clinical studies on the topic. PIVIs are ultimately submitted to the ASGE Governing Board for approval, as is done for all Technology and Standards of Practice documents. This document is provided solely for educational and informational purposes and to support incorporating these endoscopic technologies into clinical practice. It should not be construed as establishing a legal standard of care.

Race, ethnicity, sex and temporal differences in Barrett's oesophagus diagnosis: a large community-based study, 1994-2006

OBJECTIVE

To evaluate the demographics and incidence of Barrett's oesophagus diagnosis using community-based data.

DESIGN

Observational study.

SETTING

Kaiser Permanente, Northern California healthcare membership, 1994-2006.

PATIENTS

Members with an electronic diagnosis of Barrett's oesophagus.

MAIN OUTCOME MEASURES

Incidence and prevalence of a new Barrett's oesophagus diagnosis by race, sex, age and calendar year.

RESULTS

4205 persons met the study definition for a diagnosis of Barrett's oesophagus. The annual incidence in 2006 was highest among non-Hispanic whites (39/100,000 race-specific member-years, 95% confidence interval (95% CI) 35 to 43), with lower rates among Hispanics (22/100,000, 95% CI 16 to 29), Asians (16/100,000, 95% CI 11 to 22), and blacks (6/100,000, 95% CI 2 to 12). The annual incidence was higher among men than women (31 vs 17/100,000, respectively, year 2006; p<0.01). The incidence increased with age from 2 per 100,000 for persons aged 21-30 years, to a peak of 31 per 100,000 member-years for persons aged 61-70 years (year 2006). There was no increase in the incidence of new diagnoses until the last two observation years, which coincided with changes in data collection methods and may be due to bias. The overall prevalence among active members increased almost linearly to 131/100,000 member-years by 2006.

CONCLUSIONS

The demographic distributions of Barrett's oesophagus differ markedly by race, age and sex and were comparable to those for oesophageal adenocarcinoma. Thus, demographic disparities in oesophageal adenocarcinoma risk may arise partly from the risk of having Barrett's oesophagus, rather than from differing risks of progression from Barrett's oesophagus to cancer. There has been an almost linear increase in the prevalence of diagnosed disease.

Cigarette smoking and the risk of Barrett's esophagus

INTRODUCTION

We examined the association between smoking and the risk of Barrett's esophagus (BE), a metaplastic precursor to esophageal adenocarcinoma.

METHODS

We conducted a case-control study within the Kaiser Permanente Northern California population. Patients with a new diagnosis of BE (n = 320) were matched to persons with gastroesophageal reflux disease (GERD) (n = 316) and to population controls (n = 317). Information was collected using validated questionnaires from direct in-person interviews and electronic databases. Analyses used multivariate unconditional logistic regression that controlled for age, gender, race, and education.

RESULTS

Ever smoking status, smoking intensity (pack-years), and smoking cessation were not associated with the risk of BE. Stratified analyses suggested that ever smoking may be associated with an increased risk of BE among some groups (compared to population controls): persons with long-segment Barrett's esophagus (odds ratio [OR] = 1.72, 95% confidence interval [CI] 1.12-2.63); subjects without GERD symptoms (OR = 3.98, 95% CI 1.58-10.0); obese subjects (OR = 3.38, 95% CI 1.46-7.82); and persons with a large abdominal circumference (OR = 3.02, 95% CI (1.18-2.75)).

CONCLUSION

Smoking was not a strong or consistent risk factor for BE in a large community-based study, although associations may be present in some population subgroups.

Helicobacter pylori and gastroesophageal reflux disease: a case-control study

BACKGROUND

Gastric colonization with Helicobacter pylori is a proposed protective factor against gastroesophageal reflux disease (GERD), but little population-based data exist and other data conflict.

METHODS

We conducted a case-control study within the membership of a large integrated health-care system that compared GERD-free subjects with two groups: subjects with a physician-assigned GERD diagnosis and randomly selected members with self-described weekly GERD symptoms. Subjects completed interviews, GERD questionnaires, and antibody testing for H. pylori and its cagA protein.

RESULTS

Serologic data were available for 301 physician-assigned GERD patients, 81 general membership subjects with GERD symptoms, and 175 general membership subjects without GERD symptoms. Physician-assigned GERD patients were less likely to have H. pylori antibodies than GERD-free member controls (odds ratio (OR) = 0.27, 95% confidence interval (CI) 0.15-0.47); there was also an inverse association between H. pylori and GERD symptom severity (OR = 0.18, 95% CI 0.08-0.41; severe or very severe symptoms) and GERD frequency (OR = 0.18, 95% CI 0.09-0.38; for symptoms at least weekly). The association was stronger among persons with erosive GERD and was similar between H. pylori-positive subjects with and without cagA. There was no association among persons who were cagA positive, but H. pylori negative. Similar findings were found in analyses of the general membership with self-described GERD symptoms.

CONCLUSIONS

H. pylori antibody status was inversely associated with a GERD diagnosis and GERD symptoms compared with a general membership population.

Helicobacter pylori infection and the risk of Barrett's oesophagus: a community-based study

OBJECTIVE

Gastric colonisation with the Helicobacter pylori bacterium is a proposed protective factor against oesophageal adenocarcinoma, but its point of action is unknown. Its associations with Barrett's oesophagus, a metaplastic change that is a probable early event in the carcinogenesis of oesophageal adenocarcinoma, were evaluated

METHODS

A case-control study was carried out in the Kaiser Permanente Northern California population, a large health services delivery organisation. Persons with a new Barrett's oesophagus diagnosis (cases) were matched to subjects with gastro-oesophageal reflux disease (GORD) without Barrett's oesophagus and to population controls. Subjects completed direct in-person interviews and antibody testing for H pylori and its CagA (cytotoxin-associated gene product A) protein.

RESULTS

Serological data were available on 318 Barrett's oesophagus cases, 312 GORD patients and 299 population controls. Patients with Barrett's oesophagus were substantially less likely to have antibodies for H pylori (OR = 0.42, 95% CI 0.26 to 0.70) than population controls; this inverse association was stronger among those with lower body mass indexes (BMIs < 25, OR = 0.03, 95% CI 0.00 to 0.20) and those with CagA+ strains (OR = 0.08, 95% CI 0.02 to 0.35). The associations were diminished after adjustment for GORD symptoms. The H pylori status was not an independent risk factor for Barrett's oesophagus compared with the GORD controls.

CONCLUSIONS

Helicobacter pylori infection and CagA+ status were inversely associated with a new diagnosis of Barrett's oesophagus. The findings are consistent with the hypothesis that H pylori colonisation protects against Barrett's oesophagus and that the association may be at least partially mediated through GORD.

Dietary patterns and the risk of Barrett's esophagus

The objective of this study was to examine the associations between dietary patterns and the risk of Barrett's esophagus, a precursor to esophageal adenocarcinoma. The authors conducted a case-control study within the Kaiser Permanente Northern California population between 2002 and 2005. Patients with a new diagnosis of Barrett's esophagus (n = 296 cases) were matched to persons with gastroesophageal reflux disease (n = 308) without Barrett's esophagus and to population controls (n = 309). Dietary information was obtained from a validated, 110-item food frequency questionnaire. A principal component analysis was used to identify major dietary patterns. Two major dietary patterns were "Western" (high in fast food and meat) and "health-conscious" (high in fruits, vegetables, and nonfried fish). When cases and population controls were compared, strong adherence to the health-conscious dietary pattern was inversely associated with Barrett's esophagus (odds ratio = 0.35, 95% confidence interval: 0.20, 0.64; fourth vs. first quartile comparison). In contrast, data suggested an adverse effect of the Western dietary pattern on the risk of Barrett's esophagus, although no dose-effect relation was found. Results suggest strong associations between a diet rich in fruits and vegetables and the risk of Barrett's esophagus.

Incomplete screening flexible sigmoidoscopy associated with female sex, age, and increased risk of colorectal cancer

BACKGROUND

Several previous studies have found that females and older individuals are at greater risk of having incomplete flexible sigmoidoscopy. However, no prior study has reported the subsequent risk of colorectal cancer (CRC) following incomplete sigmoidoscopy.

METHODS

Using data from 55 791 individuals screened as part of the Colon Cancer Prevention (CoCaP) programme of Kaiser Permanente of Northern California, we evaluated the likelihood of having an inadequate (<40 cm) examination by age and sex, and estimated the risk of distal CRC according to depth of sigmoidoscope insertion at the baseline screening examination. Multivariate estimation of risks was performed using Poisson regression.

RESULTS

Older individuals were at a much greater risk of having an inadequate examination (relative risk (RR) for age 80+ years compared with 50-59 years 2.6 (95% confidence interval (CI) 2.3-3.0)), as were females (RR 2.3 (95% CI 2.2-2.5)); these associations were attenuated but remained strong if Poisson models were further adjusted for examination limitations (pain, stool, and angulation). There was an approximate threefold increase in the risk of distal CRC if the baseline sigmoidoscopy did not reach a depth of at least 40 cm; a smaller increase in risk was observed for examinations that reached 40-59 cm.

CONCLUSIONS

Older individuals and women are at an increased risk of having inadequate sigmoidoscopy. Because inadequate sigmoidoscopy results in an increased risk of subsequent CRC, physicians should consider steps to maximise the depth of insertion of the sigmoidoscope or, failing this, should consider an alternative screening test.

Quality in the technical performance of screening flexible sigmoidoscopy: recommendations of an international multi-society task group

BACKGROUND

Flexible sigmoidoscopy (FS) is a complex technical procedure performed in a variety of settings, by examiners with diverse professional backgrounds, training, and experience. Potential variation in technical quality may have a profound impact on the effectiveness of FS on the early detection and prevention of colorectal cancer.

AIM

We propose a set of consensus and evidence based recommendations to assist the development of continuous quality improvement programmes around the delivery of FS for colorectal cancer screening.

RECOMMENDATIONS

These recommendations address the intervals between FS examinations, documentation of results, training of endoscopists, decision making around referral for colonoscopy, policies for antibiotic prophylaxis and management of anticoagulation, insertion of the FS endoscope, bowel preparation, complications, the use of non-physicians as FS endoscopists, and FS endoscope reprocessing. For each of these areas, continuous quality improvement targets are recommended, and research questions are proposed.

CYP1A1, cigarette smoking, and colon and rectal cancer

Cytochrome P-450 (CYP) is involved in the activation and metabolism of polycyclic aromatic hydrocarbons in tobacco products. The authors evaluated the association of two polymorphisms in the CYP1A1 gene--the noncoding Msp I polymorphism in the 3'-untranslated region and the Ile462Val polymorphism in exon 7--with colon and rectal cancer. The authors used data from two incident case-control studies of colon cancer (1,026 cases and 1,185 controls) and rectal cancer (820 cases and 1,036 controls) conducted in California and Utah (1991-2002). CYP1A1 genotype was not associated with colon or rectal cancer. Having GSTM1 present, a CYP1A1 variant allele, and the rapid-acetylator NAT2 imputed phenotype was associated with increased risk of colon cancer (odds ratio = 1.7, 95% confidence interval: 1.2, 2.3). Among men, the greatest colon cancer risk was observed for having any CYP1A1 variant allele and currently smoking (odds ratio = 2.5, 95% confidence interval: 1.3, 4.8; Wald chi(2)test: p < 0.01). Assessment of GSTM1 and CYP1A1 and rectal cancer in men showed a twofold elevation in risk for more than 20 pack-years of smoking, except among those with GSTM1 present who had a variant CYP1A1 allele. These data support the association between smoking and colon and rectal cancer. Smoking may have a greater impact on colorectal cancer risk based on CYP1A1 genotype; this might further be modified by GSTM1 for rectal cancer risk.

The evolution to stool DNA testing for colorectal cancer

Despite a variety of screening strategies and recent trends showing death rate stabilization, colorectal cancer still remains the second leading cause of overall cancer death. Current screening tools suffer from performance limitations, low patient acceptability, and marginal reliable access within the health care system. Noninvasive strategies present the lowest risk with the highest potential for patient satisfaction. However, serious implementation barriers exist requiring consistent programmatic screening, strict patient adherence, and poor sensitivity for adenomas. Colonoscopy remains an invasive screening test with the best sensitivity and specificity, but faces large financial costs, manpower requirements, patient access and adherence. Development of advanced molecular techniques identifying altered DNA markers in exfoliated colonocytes signify early or precancerous growth. Stool-based DNA testing provides an entirely noninvasive population-based screening strategy which patients can perform easier than faecal occult blood testing (FOBT). Large-scale prospective randomized control trials currently pending should help characterize accurate test performance, screening intervals, cost-effectiveness, direct comparison to FOBT and analysis of patient adherence. As tumour development pathways and potential target genes are further elucidated, refinements in multi-assay stool-based DNA testing portend enhanced test characteristics to detect and treat this genetically heterogeneous disease.

Family history and colorectal cancer: predictors of risk

INTRODUCTION

While the association between family history of colorectal cancer in first-degree relatives and risk of developing colon cancer has been well defined, the association with rectal cancer is much less clear. The purpose of this study is to define rectal cancer risk associated with family history of colorectal cancer in first-degree relatives. We also evaluate diet and lifestyle factors associated with developing colorectal cancer among participants with a positive family history.

METHODS

Data were available from two population-based case--control studies of colon and rectal cancer. Participants were members of the Kaiser Permanente Medical Care Program (KPMCP) or residents of the state of Utah. Cases were first primary colon cancer diagnosed between 1991 and 1994 (n = 1308 cases and 1544 controls) or rectal cancer diagnosed between 1997 and 2001 (n = 952 cases and 1205 controls).

RESULTS

A family history of colorectal cancer in any first-degree relatives slightly increased risk of rectal cancer (OR: 1.37 95% CI: 1.02-1.85). Family history of colorectal cancer was associated with the greatest risk among those diagnosed at age 50 or younger (OR: 2.09 95% CI: 0.94-4.65 for rectal tumors; OR: 3.00 95% CI: 0.98-9.20 for distal colon tumors; and OR: 7.88 95% CI: 2.62-23.7 for proximal colon tumors). Factors significantly associated with cancer risk among those with a family history of colorectal cancer, included not having a sigmoidoscopy (OR: 2.81 95% CI: 1.86-4.24): a diet not Prudent, i.e. high in fruits, vegetables, whole grains, fish and poultry, (OR: 2.79 95% CI: 1.40-5.56); smoking cigarettes (OR: 1.68 95% CI: 1.12-2.53), and eating a Western diet, i.e. a diet high in meat, refined grains, high-fat foods, and fast foods, (OR: 2.15 95% CI: 1.06-4.35). Physical inactivity was not associated with increased cancer risk among those with a positive family history of colorectal cancer.

SUMMARY

These results confirm observations reported by others that a family history of colorectal cancer increases risk of cancer among those diagnosed at a younger age. Associations with family history are weakest for rectal cancer and strongest for proximal colonic tumors. Since several diet and lifestyle factors influence development of cancer among those with a family history of the disease, there appears to be practical approaches for individuals with a family history of colorectal cancer to reduce their cancer risk.

Family history and colorectal cancer: predictors of risk

INTRODUCTION

While the association between family history of colorectal cancer in first-degree relatives and risk of developing colon cancer has been well defined, the association with rectal cancer is much less clear. The purpose of this study is to define rectal cancer risk associated with family history of colorectal cancer in first-degree relatives. We also evaluate diet and lifestyle factors associated with developing colorectal cancer among participants with a positive family history.

METHODS

Data were available from two population-based case--control studies of colon and rectal cancer. Participants were members of the Kaiser Permanente Medical Care Program (KPMCP) or residents of the state of Utah. Cases were first primary colon cancer diagnosed between 1991 and 1994 (n = 1308 cases and 1544 controls) or rectal cancer diagnosed between 1997 and 2001 (n = 952 cases and 1205 controls).

RESULTS

A family history of colorectal cancer in any first-degree relatives slightly increased risk of rectal cancer (OR: 1.37 95% CI: 1.02-1.85). Family history of colorectal cancer was associated with the greatest risk among those diagnosed at age 50 or younger (OR: 2.09 95% CI: 0.94-4.65 for rectal tumors; OR: 3.00 95% CI: 0.98-9.20 for distal colon tumors; and OR: 7.88 95% CI: 2.62-23.7 for proximal colon tumors). Factors significantly associated with cancer risk among those with a family history of colorectal cancer, included not having a sigmoidoscopy (OR: 2.81 95% CI: 1.86-4.24): a diet not Prudent, i.e. high in fruits, vegetables, whole grains, fish and poultry, (OR: 2.79 95% CI: 1.40-5.56); smoking cigarettes (OR: 1.68 95% CI: 1.12-2.53), and eating a Western diet, i.e. a diet high in meat, refined grains, high-fat foods, and fast foods, (OR: 2.15 95% CI: 1.06-4.35). Physical inactivity was not associated with increased cancer risk among those with a positive family history of colorectal cancer.

SUMMARY

These results confirm observations reported by others that a family history of colorectal cancer increases risk of cancer among those diagnosed at a younger age. Associations with family history are weakest for rectal cancer and strongest for proximal colonic tumors. Since several diet and lifestyle factors influence development of cancer among those with a family history of the disease, there appears to be practical approaches for individuals with a family history of colorectal cancer to reduce their cancer risk.

Factors associated with colorectal cancer screening in a population-based study: the impact of gender, health care source, and time

INTRODUCTION

The effectiveness of colorectal cancer screening in reducing incident colorectal cancer and the risk of death has been shown. Despite campaigns to promote the benefits of and use of colorectal cancer screening, most people are not participating in screening. In this paper, we examine factors associated with screening behavior over time, by health care provider, and by gender and report associations between screening and development of colorectal cancer after adjusting for diet and lifestyle factors.

METHODS

Data from two population-based case-control studies of colorectal cancer were used to examine risk associations with nonparticipation in colorectal cancer screening. Study participants were identified for the first study between 1991 and 1994 (N = 1,346 cases and 1,544 controls) and for the second between 1997 and 2001 (N = 952 cases and 1,205 controls) and were asked to complete a detailed in-person interviewer-administered diet and lifestyle questionnaire. The control population is used to examine changes in screening behavior and associations with screening over time.

RESULTS

Significantly, fewer people reported fecal occult blood test (FOBT) in 1997-2001 than in 1991-1994 (62.5% in 1991-1994 vs. 47.2% in 1997-2001); a slight nonsignificant increase in sigmoidoscopy screening was reported for these periods among controls (33.9% vs. 36.6%). In the control population, during these periods, there was a statistically significant increase in the number of people who reported having had a sigmoidoscopy for screening rather than for problems (72.6% in 1997-2001 vs. 63.8% in 1991-1994). There were differences in factors associated with screening behavior by time, by sex, and by health care provider, although having a family history of colorectal cancer, having more education, and being male was associated with more screening in all settings. After adjusting for diet and lifestyle factors, we observed that non-sigmoidoscopy screening significantly influenced risk of incident cancer (rectal OR: 2.9; 95% CI, 2.3-3.7; distal tumor OR: 1.8; 95% CI, 1.4-2.3); proximal tumor: 1.4; 95% CI, 1.1-1.8). Nonuse of FOBT also was associated significantly with tumors in the rectal (OR: 1.6; 95% CI, 1.3-1.9) and distal (OR: 1.4; 95% CI, 1.1-1.8) sites.

SUMMARY

These data reinforce the importance of screening to reduce risk of colorectal cancer development. However, flexible sigmoidoscopy screening is increasing only modestly over time, and primarily in settings where a significant investment in screening has been made. FOBT screening, which is effective for rectal cancer prevention, is actually decreasing.

Gastric and duodenal safety of daily alendronate

BACKGROUND

Isolated case reports of gastric ulcers after alendronate sodium use raised concern about the gastroduodenal safety of daily alendronate. This study was conducted to estimate the excess risk of hospitalizations for gastric or duodenal perforations, ulcers, and bleeding associated with alendronate use.

PARTICIPANTS AND METHODS

Study subjects were 6432 men and women, 35 years or older. The subjects were members of 8 health maintenance organizations who were dispensed alendronate from October 1995 through September 1997. There was also a group of 33 176 age-, sex-, and health maintenance organization-matched unexposed persons. Because of concerns that osteoporosis might confound the association between alendronate use and perforation, ulcer, or bleeding, a second comparison group of 9776 women, 60 years or older, who had osteoporotic fractures was assembled. Hospitalizations for gastroduodenal events were identified by discharge diagnosis codes in automated claims records, and confirmed by manual record review.

RESULTS

Based on the 14 confirmed events in the alendronate group and 35 in the unexposed group, the crude incidence rate ratio of gastroduodenal perforation, ulcer, or bleeding for the alendronate cohort was 3.0. The incidence rate ratio was 1.8 (95% confidence interval, 0.8-3.9) after control for prior hospitalizations, comorbidity, and recent exposure to prescription nonsteroidal anti-inflammatory drugs and oral corticosteroids. The crude incidence ratio rate for the age, sex, and health maintenance organizations-restricted cohort of alendronate users relative to the fracture cohort was 1.1 and the adjusted incidence rate ratio was 1.1 (95% confidence interval, 0.6-2.2).

CONCLUSIONS

Osteoporosis and related factors appear to play an important role in the relationship between alendronate use and confirmed gastroduodenal perforation, ulcer, or bleeding; a substantial fraction of the increased risk we observed for alendronate users in the unadjusted analysis was the result of confounding.

Validation of diagnoses of peptic ulcers and bleeding from administrative databases: a multi-health maintenance organization study

The automated health plan data and data from medical chart abstractions from eight large health maintenance organizations were used to evaluate the positive predictive values (PPVs) of the International Classification of Diseases, 9th revision (ICD-9) codes for cases of peptic ulcers and upper gastrointestinal bleeding. Overall, 207 of 884 cases of peptic ulcers and upper gastrointestinal bleeding (23%) were confirmed by surgery, endoscopy, X-ray, or autopsy. The PPVs were 66% for hospitalizations with codes for duodenal ulcer (ICD-9-CM 532), 61% for gastric/gastrojejunal ulcer (ICD-9-CM 531, 534), 1% for peptic ulcer (ICD-9-CM 533), and 9% for gastrointestinal hemorrhage (ICD-9-CM578). The overall and diagnostic category-specific PPVs were generally similar for the various HMOs. This study, using data from a large number of health plans located in different geographical regions, underscores the importance of evaluating the accuracy of the diagnoses from automated health plan databases.

Quality of life measurement clarifies the cost-effectiveness of Helicobacter pylori eradication in peptic ulcer disease and uninvestigated dyspepsia

OBJECTIVES

Previous economic studies of Helicobacter pylori eradication in dyspepsia and peptic ulcer disease have not measured quality of life using utilities (preference probabilities), which are needed to compare the cost-effectiveness of such treatment to other health care interventions. The goals of this study were to measure quality of life in patients with dyspepsia or peptic ulcer and apply these measurements to published models of disease management to determine cost-effectiveness in dollars per quality-adjusted life year (QALY) gained.

METHODS

Utilities for dyspepsia and peptic ulcer disease were measured in adult patients (n = 73) on chronic acid suppression for peptic ulcer or ulcer-like dyspepsia. Median utility values were applied to the results of published cost-effectiveness analyses and a previously validated dyspepsia model. Cost-utility ratios for early H. pylori eradication in uninvestigated dyspepsia and peptic ulcer disease were then computed.

RESULTS

The total disutility, or lost quality of life, for an ulcer was 0.11 QALY, of which 0.09 QALY was attributed to dyspeptic symptoms. After these results were incorporated into published studies, cost-utility ratios for ulcer treatment varied from $3,100 to $12,500 per QALY gained, whereas estimates for uninvestigated dyspepsia management ranged from $26,800 to $59,400 per QALY. Sensitivity analyses indicated a range of $1,300 to $27,300 per QALY for management of duodenal ulcer and $15,000 to $129,700 per QALY for dyspepsia.

CONCLUSIONS

Strategies that emphasize early H. pylori eradication were cost-effective for patients with peptic ulcer and possibly cost-effective for patients with uninvestigated dyspepsia, relative to other medical interventions. Dyspeptic symptoms cause significant disutility that should be incorporated in future cost-effectiveness analyses of treatment strategies.

Efficient detection of hereditary nonpolyposis colorectal cancer gene carriers by screening for tumor microsatellite instability before germline genetic testing

BACKGROUND & AIMS

The optimal strategy for the detection of hereditary nonpolyposis colorectal cancer (HNPCC) gene carriers remains uncertain. We evaluated whether microsatellite instability (MSI) analysis or MSH2 and MLH1 protein immunostaining of tumors will screen individuals efficiently for germline MSH2 and MLH1 testing.

METHODS

We performed a case-series study of 114 eligible families enrolled in our high-risk colorectal cancer (CRC) registry. Medical history data were collected on probands and relatives. MSI analysis was performed on proband tumors, and MSH2 and MLH1 protein immunostaining was assessed. Denaturing gradient gel electrophoresis was used to identify germline MSH2 or MLH1 mutations in probands found to have tumors with high-frequency MSI.

RESULTS

Tumor tissue and adequate clinical data were available in 109 of the 114 families. Amsterdam criteria and Bethesda guidelines were met by 23% and 70% of the families, respectively. High-frequency MSI was identified in the proband tumors in 47 of the 109 families (43%). Germline MSH2 and MLH1 gene testing was carried out in the probands of 32 of 47 families with MSI-H tumors. Mutations were detected in 16 families (9 in MSH2 and 7 in MLH1) and sequence variants of uncertain significance in 5 families (1 in MSH2 and 4 in MLH1). Germline mutations or sequence variants of uncertain significance were detected in 15 of 19 (79%) of our Amsterdam families and in 6 of 13 (46%) of our non-Amsterdam families with MSI-H tumors. MSH2 and MLH1 protein immunostaining was assessed in 38 of the 47 MSI-H tumors. Unequivocal loss of hMLH1 expression was found in 20 tumors and loss of MSH2 expression in 9 tumors. Corresponding loss of protein expression was seen in 17 of 18 (94%) of tumors from probands with germline mutations or variants.

CONCLUSIONS

The detection of high-frequency MSI or the loss of MSH2 or MLH1 immunostaining in CRCs are both useful criteria for selecting high-risk patients who should be tested for germline mutations in MSH2 or MLH1.

Work loss costs due to peptic ulcer disease and gastroesophageal reflux disease in a health maintenance organization

OBJECTIVE

The aim of this study was to estimate the value of work time and productivity loss because of peptic ulcer disease (PUD) and gastroesophageal reflux disease (GERD).

METHODS

A total of 300 adult members of Northern California Kaiser Permanente Medical Care Program with outpatient diagnoses of PUD or GERD were randomly selected for a record review to confirm diagnosis. A telephone survey was conducted soliciting information about work loss because of their disease. Reported work losses were valued at self-reported hourly wage to derive work loss costs. A total of 117 PUD and 102 GERD patients participated.

RESULTS

About 75% of each sample was employed full-time or part-time. In all, 42% of potentially working PUD patients and 41% of GERD patients reported some lost work productivity because of their disease. The average loss (per person working) was $606 for PUD and $237 for GERD over a 3-month period. Reduced productivity while at work and part-time work because of the disease were the most costly productivity losses for PUD, whereas time off for physician visits and reduced productivity while at work were the most costly losses for GERD.

CONCLUSIONS

Work loss costs for patients with PUD and GERD may be nearly as large as direct medical care costs, and are consistent with the more acute nature of PUD and the chronic pattern of GERD. The work losses resulting from these diseases are large enough to warrant consideration in guideline development and policy decisions for patients with PUD and GERD.

Colorectal cancer screening: new opportunities

Colorectal cancer is the third most common cancer among men and women in the United States, and the third leading cause of cancer death. Strategies currently available to screen for colorectal cancer include fecal occult blood tests, sigmoidoscopy, or both tests used in combination. Colonoscopy and double contrast barium enema are potentially preferable options because they offer improved sensitivity over currently available tests, but the feasibility of these tests for population screening remains in doubt. Future opportunities for screening include focusing special efforts to deliver screening to higher risk individuals based on family history or age and the use of molecular or computer-aided radiographic techniques as alternatives to colonoscopy.

Predicting advanced proximal colonic neoplasia with screening sigmoidoscopy

CONTEXT

Indications are not well defined for follow-up colonoscopy for all patients with distal colonic tubular adenomas (TAs) found at screening sigmoidoscopy.

OBJECTIVE

To determine whether distal adenoma size, number, and villous histology, along with family history and age, are predictors of advanced proximal colonic neoplasia.

DESIGN

Cross-sectional analysis conducted between January 1, 1994, and December 31, 1995.

SETTING

Large group-model health maintenance organization in northern California.

PATIENTS

A total of 2972 asymptomatic subjects aged 50 years or older undergoing colonoscopy as follow-up to a screening sigmoidoscopy.

MAIN OUTCOME MEASURE

Based on sigmoidoscopy, colonoscopy, and pathology reports, occurrence of advanced proximal neoplasia, defined as adenocarcinoma or TAs 1 cm or larger or with villous features or severe dysplasia located beyond sigmoidoscopic view.

RESULTS

The prevalence of advanced proximal neoplasia was similar among patients with no TAs at sigmoidoscopy, those with TAs less than 1 cm in diameter, and those with TAs 1 cm in diameter or larger (prevalence, 5.3%, 5.5%, and 5.6%, respectively). Of patients with a distal tubulovillous or villous adenoma, 12.1% had advanced proximal neoplasia. In multivariate analyses, having a distal tubulovillous adenoma or villous adenoma was the strongest predictor of advanced proximal neoplasia (odds ratio, 2.30; 95% confidence interval, 1.69-3.14). Age of 65 years or older, having more than 1 adenoma, and a positive family history of colorectal cancer were also significant predictors. Distal adenoma size was not a significant predictor in any multivariate analyses.

CONCLUSIONS

Advanced proximal neoplasia is not uncommon in subjects with or without distal TAs, but subjects with advanced distal histology and those older than 65 years are at increased risk. Age-specific screening using sigmoidoscopy starting at ages 50 to 55 years and colonoscopy after age 65 years may be justified.

Omeprazole improves peak expiratory flow rate and quality of life in asthmatics with gastroesophageal reflux

OBJECTIVE

The aim of this study was to determine if omeprazole improves pulmonary function and quality of life in asthmatics with gastroesophageal reflux.

METHODS

This was a double blind, randomized, placebo-controlled cross-over trial. After a 4-wk lead-in period, nine patients with documented asthma and gastroesophageal reflux, were prescribed either omeprazole 20 mg, daily or placebo for 8 wk and then crossed over to the alternate treatment. Outcome measurements included: forced expiratory volume at 1 s (FEV1), peak expiratory flow rate (PEFR), and responses on the Asthma Quality of Life Questionnaire, a validated disease specific measure of functional status.

RESULTS

After omeprazole treatment, compared with placebo, patients had higher mean morning and evening PEFR, mean absolute difference (95% CI): morning: 37.8 L/min. (10.9-64.6), evening: 31.2 (3.2-59.2). Omeprazole treatment led to higher mean overall scores on the Asthma Quality of Life Questionnaire, and on the subdomains of activity limitation, symptoms, and emotions (p = 0.039, 0.049, 0.024, 0.040). A trend toward higher FEV1 (mean: 15.6% difference) with omeprazole failed to reach statistical significance (p > 0.2).

CONCLUSIONS

After taking omeprazole for 8 wk, asthmatics with GER have better PEFR and quality of life than after placebo.

A cost analysis of a Helicobacter pylori eradication strategy in a large health maintenance organization

OBJECTIVES

We sought to describe the effect of a Helicobacter pylori eradication strategy on health care costs among a cohort of health maintenance organization (HMO) members with peptic ulcer disease (PUD).

METHODS

Patients were identified from an outpatient diagnosis database and verified at chart review to have new-onset PUD by upper endoscopy or upper gastrointestinal radiographic series. Health plan registration and accounting databases were used to track costs over 12 months after initial diagnosis. Costs were analyzed separately for an initial 2-month interval and a 10-month follow-up period. Inpatient and pharmacy costs are those directly attributable to PUD (either a PUD-related discharge diagnosis or an antiulcer medication prescription). Outpatient costs are total costs. All cost differences were adjusted for age and gender.

RESULTS

Twenty-seven of 93 patients meeting selection criteria received H. pylori treatment. During the 2-month treatment window, adjusted PUD-related inpatient costs were higher for the H. pylori treated group (difference, $234.00/person), whereas total outpatient costs and PUD-related pharmacy costs were similar. During the 10-month follow-up period, PUD-related inpatient and pharmacy adjusted costs were similar, but adjusted outpatient costs in the H. pylori treated group were lower than in the untreated group (difference, $508.00/person). Total adjusted follow-up period costs were $555.00/person less in the H. pylori treated group (p = 0.05). Total 12-month costs in the H. pylori treated group were $285.00/per person less than in untreated patients, (p > 0.2); 30% of H. pylori treated patients were still receiving antisecretory therapy 1 yr after diagnosis, compared to 41.9% of untreated patients.

CONCLUSIONS

H. pylori treatment is associated with a decreased cost of follow-up care for patients with PUD, primarily due to decreased outpatient utilization.

Costs of acid-related disorders to a health maintenance organization

BACKGROUND

Little is known about the economic impact of the acid-related disorders (ARDs), which include dyspepsia, gastritis, gastroesophageal reflux disease (GERD), and peptic ulcer disease (PUD), in managed care patient populations.

OBJECTIVES

To describe the prevalence of medically attended ARDs, and their direct medical costs from the perspective of a large health maintenance organization (HMO).

METHODS

A total of 1,550 ARDs subjects (age > or = 18 years), were randomly sampled from outpatient diagnosis and pharmacy databases of the Kaiser Permanente Medical Care Program of Northern California and verified by chart review. Five age- and gender-matched controls were identified per subject. One-year prevalence, excess annual costs, and initial 6-month costs for incident cases were estimated using the HMO cost accounting system.

RESULTS

Total ARDs prevalence (5.8%) increases with advancing age. GERD is the most common ARD (2.9% overall prevalence). Annual per person attributable costs were $1,183, $471, and $431 respectively for PUD, GERD, and gastritis/dyspepsia. Excess inpatient costs for PUD explain its higher costs. Outpatient costs were somewhat higher for GERD ($279) than for PUD or gastritis/dyspepsia. Pharmacy costs were relatively low for each condition, in part because many patients were treated with generic cimetidine. Total annual HMO expenditures for ARDs were $59.4 million, with 40.6%, 36.8%, and 22.6% respectively for GERD, PUD, and gastritis/dyspepsia.

CONCLUSIONS

Acid-related disorders, particularly GERD and PUD, contribute substantially to the direct costs of medical care in this managed care population.

Organic mood disorder associated with the HAIR-AN syndrome

The HAIR-AN syndrome is characterized by hyperandrogenism, insulin resistance, and acanthosis nigricans. The authors report the first case of an organic mood disorder associated with this condition that improved markedly in response to ovarian suppression with oral contraceptives. The proposed pathophysiology of this syndrome is also discussed.