Type-2 Diabetes Mellitus and Risk of Colorectal Polyps: A Colonoscopy-Based Study Using Natural Language Processing

PURPOSE

Although type-2 diabetes (T2D) has been associated with colorectal cancer in previous studies, the association of T2D with colorectal polyps is unknown.

METHODS

Using pathology reports from the University of Utah (UU) Enterprise Data Warehouse (EDW), we developed a rule-based natural language processing (NLP) pipeline to extract colorectal polyp diagnoses and features (site, shape, number, size) on 15,679 patients who underwent a colonoscopy at the UU Gastroenterology clinic from 2013-2016. The NLP pipeline was validated by manual abstraction of 350 pathology reports, and demonstrated excellent performance (accuracy 91%). Patient characteristics, including age, sex, race, diabetes status, smoking, BMI, and medication use, were abstracted from the EDW. Odds ratios (OR) and 95% confidence limits (95% CI) adjusted for abstracted variables were calculated using multivariable polytomous logistic regression.

RESULTS

Participants were on average 56 years old, 85% White, 50% male, with a mean BMI of 29 kg/m2. About 27% of the participants reported history of T2D; 71% of whom used anti-diabetes medication. Participants were classified as having adenomas (30%), serrated polyps (16%), synchronous adenomas and serrated polyps (19%) or as polyp-free controls (35%). T2D was associated with a statistically significant lower risk of colorectal polyps [0.83(0.73,0.92)]. When evaluated by polyp subtype, T2D was marginally associated with reduced adenoma risk [0.90(0.80,1.02)], and inversely associated with risk of serrated polyps [0.80(0.67,0.93)]. The associations did not vary by lesion severity within polyp subtypes. There was a statistically significant deceased risk for polyps among anti-diabetes medication users [0.84(0.69,0.99)].

CONCLUSIONS

Overall, T2D was associated with a statistically significant reduced risk of colorectal polyps; this reduced risk was consistent for both adenomas and serrated polyps. As T2D has previously been shown to increase colorectal cancer risk, this differential association with colorectal polyps may possibly be due to a variable effect of anti-diabetes medication use. Further studies are needed to better understand the mechanisms through which diabetes and its treatment may be differentially associated with colorectal polyps.

Greater loss of productivity among Japanese workers with gastro-esophageal reflux disease (GERD) symptoms that persist vs resolve on medical therapy

BACKGROUND

Gastro-esophageal reflux disease (GERD) impairs quality of life; however, the association between GERD and work productivity has not been well investigated in Japan. This study was designed to compare the impact of GERD on productivity between Japanese workers with GERD symptoms that persisted vs resolved on medical therapy.

METHODS

A cross-sectional Web-based survey was conducted in workers. The impact of GERD on work and daily productivity was evaluated using a Web-reported Work Productivity and Activity Impairment Questionnaire for patients with GERD and a GERD symptom severity Questionnaire. Demographic information, clinical history, and satisfaction with GERD medication were also ascertained.

KEY RESULTS

A total of 20 000 subjects were invited to the survey. After the exclusion of patients with a history of gastrointestinal (GI) malignancy, peptic ulcer, upper GI surgery, and unemployment, 650 participants were included in the analysis. Participants with persistent GERD symptoms reported a significantly greater losses of work productivity (11.4 ± 13.4 h/week), absenteeism (0.7 ± 3.1 h/week), presenteeism (10.7 ± 12.6 h/week), costs (20 100 ± 26 800 JPY/week), and lower daily productivity (71.3% [95% confidence interval, 69.0-73.7]) than those whose symptoms were alleviated with medications. The level of dissatisfaction with GERD medications among participants with persistent GERD symptoms was significantly correlated with loss of work and daily productivity (p < 0.001).

CONCLUSIONS & INFERENCES

GERD places a significant burden on work and daily productivity despite medical therapy. Ineffective GERD therapy is associated with greater productivity loss.

Classification of functional dyspepsia based on concomitant bowel symptoms

BACKGROUND

  Functional dyspepsia (FD) is a heterogeneous disease, and categorized into postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). However, many FD patients have overlap of both PDS and EPS. The present study was designed to examine whether FD could be categorized based on the presence of concomitant gastrointestinal symptoms.

METHODS

  A web survey comprised of the Gastrointestinal Symptom Rating Scale (GSRS), Rome III criteria of FD, and demographic information was sent to public participants who have no history of severe illness. Factor and cluster analyses were conducted to identify sub-categories of FD based on GSRS.

KEY RESULTS

  A total of 8038 participants completed the survey. A total of 563 participants met the criteria for FD, whereas 6635 participants did not have dyspepsia symptoms. The remainder had either organic disease (377) or uninvestigated dyspepsia (463). The cluster analysis categorized participants as constipation predominant (cluster C), diarrhea predominant (cluster D), or having neither diarrhea nor constipation (cluster nCnD). Cluster C and D were significantly associated with the presence of FD [odds ratio (OR) 2.57, 95% confidence interval (CI) 2.06-3.21; OR 2.80; 95% CI 2.27-3.45, respectively]. In FD, especially in PDS cases, the scores of upper gastrointestinal symptoms were higher in cluster C or D than in cluster nCnD.

CONCLUSIONS & INFERENCES

  The severity of dyspepsia symptoms is associated with the presence of bowel symptoms especially in PDS. This novel categorization of FD based on concomitant constipation or diarrhea may improve classification of patients.

Japanese herbal medicine in functional gastrointestinal disorders

Management of functional gastrointestinal disorders is hindered by both poor efficacy and adverse effects of traditional pharmacological therapy. Herbal medicine may be an attractive alternative based on the perception of its 'natural' approach and low risk of side effects; however, the lack of standardization of drug components has limited the ability to perform rigorous clinical studies in Western countries. Japanese herbal medicine (JHM) is a standardized form of herbal medicine with regards to the quality and quantities of ingredients. While extensively studied and widely used in Asia, there is a paucity of data upon which physicians in other parts of the world may draw conclusions regarding the effectiveness of herbal medicine for gastrointestinal disorders. The aim of this study was to summarize the most recent developments in JHM for treatment of functional gastrointestinal disorders. Animal and human studies were systematically reviewed to identify published data of JHM used for treatment of gastrointestinal disorders. The herbal components of JHM were examined. Results describing the physiological and clinical effects of JHM were abstracted, with an emphasis on functional gastrointestinal disorders. JHM are associated with a variety of beneficial physiological on the gastrointestinal system. Patient-based clinical outcomes are improved in several conditions. Rikkunnshi-to reduces symptoms and reverses physiological abnormalities associated with functional dyspepsia, while dai-kenchu-to improves symptoms of postoperative ileus and constipation in children. This updated summary of JHM in the field of gastrointestinal disorders illustrates the potential for herbal medication to serve a valuable role in the management of patients with functional gastrointestinal disorders.

NIH consensus development statement on management of hepatitis B

OBJECTIVE

To provide health care providers, patients, and the general public with a responsible assessment of currently available data on the management of hepatitis B.

PARTICIPANTS

A non-DHHS, nonadvocate 12-member panel representing the fields of hepatology and liver transplantation, gastroenterology, public health and epidemiology, infectious diseases, pathology, oncology, family practice, internal medicine, and a public representative. In addition, 22 experts from pertinent fields presented data to the panel and conference audience.

EVIDENCE

Presentations by experts and a systematic review of the literature prepared by the Minnesota Evidence-based Practice Center, through the Agency for Healthcare Research and Quality. Scientific evidence was given precedence over anecdotal experience.

CONFERENCE PROCESS

The panel drafted its statement based on scientific evidence presented in open forum and on published scientific literature. The draft statement was presented on the final day of the conference and circulated to the audience for comment. The panel released a revised statement later that day at http://consensus.nih.gov. This statement is an independent report of the panel and is not a policy statement of the NIH or the Federal Government.

CONCLUSIONS

The most important predictors of cirrhosis or hepatocellular carcinoma in persons who have chronic HBV are persistently elevated HBV DNA and ALT levels in blood. Other risk factors include HBV genotype C infection, male sex, older age, family history of hepatocellular carcinoma, and co-infection with HCV or HIV. The major goals of anti-HBV therapy are to prevent the development of progressive disease, specifically cirrhosis and liver failure, as well as hepatocellular carcinoma development and subsequent death. To date, no RCTs of anti-HBV therapies have demonstrated a beneficial impact on overall mortality, liver-specific mortality, or development of hepatocellular carcinoma. Most published reports of hepatitis therapy use changes in short-term virologic, biochemical, and histologic parameters to infer likelihood of long-term benefit. Approved therapies are associated with improvements in intermediate biomarkers, including HBV DNA, HBeAg loss or seroconversion, decreases in ALT levels, and improvement in liver histology (Table). Although various monitoring practices have been recommended, no clear evidence exists for an optimal approach. The most important research needs include representative prospective cohort studies to define the natural history of the disease and large RCTs of monotherapy and combined therapies, including placebo-controlled trials, that measure the effects on clinical health outcomes. Table. Criteria Useful in Determining for Whom Therapy is Indicated: Patients for whom therapy is indicated: Patients who have acute liver failure, cirrhosis and clinical complications, cirrhosis or advanced fibrosis and HBV DNA in serum, or reactivation of chronic HBV after chemotherapy or immunosuppression; Infants born to women who are HBsAg-positive (immunoglobulin and vaccination). Patients for whom therapy may be indicated: Patients in the immune-active phase who do not have advanced fibrosis or cirrhosis. Patients for whom immediate therapy is not routinely indicated: Patients with chronic hepatitis B in the immune-tolerant phase (with high levels of serum HBV DNA but normal serum ALT levels or little activity on liver biopsy); Patients in the inactive carrier or low replicative phase (with low levels of or no detectable HBV DNA in serum and normal serum ALT levels); Patients who have latent HBV infection (HBV DNA without HBsAg). We recommend routine screening for hepatitis B of newly arrived immigrants to the United States from countries where the HBV prevalence rate is greater than 2%. Screening will facilitate the provision of medical and public health services for infected patients and their families and provide public health data on the burden of disease in immigrant populations. The screening test should not be used to prohibit immigration.

Oesophageal hypersensitivity is associated with features of psychiatric disorders and the irritable bowel syndrome

BACKGROUND

Twenty per cent of patients with heartburn do not respond to proton pump inhibitors (PPIs). Many have normal oesophageal acid exposure. We hypothesized that such PPI non-responders have heightened oesophageal sensation, and that oesophageal hypersensitivity is associated with psychiatric features including somatization and anxiety.

AIM

To compare oesophageal sensation in subjects with heartburn categorized by response to PPI, and to correlate oesophageal sensation with psychiatric features.

METHODS

Twenty-one PPI responders, nine PPI non-responders and 20 healthy volunteers completed questionnaires of psychiatric disorders and gastrointestinal symptoms. Subjects underwent oesophageal sensory testing with acid perfusion and balloon distension.

RESULTS

Healthy volunteers displayed higher thresholds for sensation and discomfort from balloon distension than heartburn subjects (sensation P = 0.04, discomfort P = 0.14). Psychiatric disorders were associated with increased intensity of sensation (P = 0.02) and discomfort from acid (P = 0.01). Somatization was associated with increased discomfort from balloon distension (P = 0.006). Features of irritable bowel syndrome were associated with increased sensation and discomfort.

CONCLUSIONS

Heartburn subjects tend to have heightened oesophageal sensation, suggesting that oesophageal hypersensitivity may persist despite therapy with PPI. Oesophageal hypersensitivity is associated with features of psychiatric disease and with the irritable bowel syndrome, which might partly explain the aetiology of heartburn symptoms that are refractory to PPI.

Primary care physician perceptions of non-steroidal anti-inflammatory drug and aspirin-associated toxicity: results of a national survey

AIM

To assess primary care physician perceptions of non-steroidal anti-inflammatory drug (NSAID) and aspirin-associated toxicity.

METHODS

A group of gastroenterologists and internal medicine physicians created a survey, which was administered via the Internet to a large number of primary care physicians from across the US.

RESULTS

One thousand primary care physicians participated. Almost one-third of primary care physicians recommended 325 mg rather than 81 mg of aspirin/day for cardioprotection. Fifty-nine percent thought enteric-coated or buffered aspirin reduced the risk of upper gastrointestinal (GI) bleeding. Seventy-six percent believed that Helicobacter pylori infection increased the risk of NSAID ulcers but fewer than 25% tested NSAID users for this infection. More than two-thirds were aware that aspirin co-therapy decreased the GI safety benefits of the cyclo-oxygenase 2 selective NSAIDs. However, 84% felt that aspirin with a cyclo-oxygenase 2 selective NSAID was safer than aspirin with a non-selective NSAID. When presented a patient at high risk for NSAID-related GI toxicity, almost 50% of primary care physicians recommended a proton pump inhibitor and cyclo-oxygenase 2 selective NSAID.

CONCLUSIONS

This survey has identified areas of misinformation regarding the risk-benefit of NSAIDs and aspirin and the utilization of gastroprotective strategies. Further education on NSAIDs for primary care physicians is warranted.

Relationship between diabetes mellitus and adenocarcinoma of the oesophagus and gastric cardia

BACKGROUND

Obesity is a risk factor for adenocarcinomas of the oesophagus and gastric cardia. Diabetes mellitus might mediate that association.

AIM

To estimate the risk of diabetes mellitus on the development of adenocarcinoma of distal oesophagus and gastric cardia beyond that of gastro-oesophageal reflux disease.

METHODS

A case-control study was performed using a national administrative database of the Veterans Administration.

RESULTS

A total of 311 cases of cancer and 10,154 controls were identified. Gender, age, and race were risks for cancer. Diabetes was diagnosed in 36% of cases, and 32% of controls (P = 0.15). Diabetic complications were diagnosed in 14% of cases and 13% of controls (P = 0.60). Multiple logistic regression confirmed the absence of an association between cancer and diabetes (odds ratio 1.1, 95% confidence interval 0.8-1.5) or diabetic complications (odds ratio 0.8, 95% confidence interval 0.6-1.3), adjusting for age, gender, and race.

CONCLUSIONS

Within the limitations of this case-control study, there is no evidence of an association between diabetes and adenocarcinoma of the oesophagus or gastric cardia among US veterans with gastro-oesophageal reflux disease.

The cost-effectiveness of biomarkers for predicting the development of oesophageal adenocarcinoma

BACKGROUND

The recommended surveillance strategy for oesophageal adenocarcinoma may prevent as few as 50% of cancer deaths. Tissue biomarkers have been proposed to identify high-risk patients.

AIM

To determine performance characteristics of an ideal biomarker, or panel of biomarkers, that would make its use more cost-effective than the current surveillance strategy.

METHODS

We created a Markov model using data from published literature, and performed a cost-utility analysis. The population consisted of 50-year-old Caucasian men with gastro-oesophageal reflux, who were monitored until age 80. We examined strategies of observation only, current practice (dysplasia-guided surveillance), surveillance every 3 months for patients with a positive biomarker (biomarker-guided surveillance), and oesophagectomy immediately for a positive biomarker (biomarker-guided oesophagectomy). The primary outcome was the threshold cost and performance characteristics needed for a biomarker to be more cost-effective than current practice.

RESULTS

Regardless of the cost, the biomarker needs to be at least 95% specific for biomarker-guided oesophagectomy to be cost-effective. For biomarker-guided surveillance to be cost-effective, a $100 biomarker could be 80% sensitive and specific.

CONCLUSIONS

Biomarkers predicting the development of oesophageal adenocarcinoma would need to be fairly accurate and inexpensive to be cost-effective. These results should guide the development of biomarkers for oesophageal adenocarcinoma.

What is the best management strategy for high grade dysplasia in Barrett's oesophagus? A cost effectiveness analysis

BACKGROUND

Multiple treatment strategies for subjects with high grade dysplasia (HGD) in Barrett's oesophagus (BO) have been suggested. However, it is unclear which of these strategies provides the greatest life expectancy, and the costs associated with the management strategies are unknown.

AIM

To compare the efficacy and cost effectiveness of competing management strategies for BO with HGD.

METHODS

We created a decision analysis model in Data 4.0 to assess possible treatment strategies for BO with HGD. The strategies included: (1) no preventative strategy, (2) elective surgical oesophagectomy, (3) endoscopic ablation, and (4) surveillance endoscopy. The base case was a healthy 50 year old White male with an initial diagnosis of BO with HGD. The model allowed for complications of surgery, including death. Ablative therapy could cause stricture or perforation. Pathological misinterpretation was allowed, and modelled after reported rates. Estimates were derived from the literature for the rate of progression of HGD to cancer and for complication rates for the various treatment modalities. The endoscopic ablation arm was modelled as photodynamic therapy. Sensitivity analyses were performed over a wide range of cancer incidences, complication rates, and procedure costs.

RESULTS

Endoscopic ablation was the most effective strategy, yielding 15.5 discounted quality adjusted life years (dQALY), compared with 15.0 for endoscopic surveillance and 14.9 for oesophagectomy. No preventative strategy was the most inexpensive option, yielding an average cost per quality adjusted life year of US dollars 54 (44) per dQALY, but resulted in high rates of cancer. Endoscopic surveillance dominated oesophagectomy, being both less costly and more effective. The condition of extended dominance occurred when comparing endoscopic ablation to endoscopic surveillance because, although the total costs of ablation were greater than those of surveillance, it was less expensive to buy an additional life year using endoscopic ablation than endoscopic surveillance. The incremental cost effectiveness ratio when moving from no therapy to ablative therapy was a reasonable US dollars 25 621/dQALY (21 009/dQALY). Sensitivity analysis demonstrated that when yearly rates of progression to cancer from HGD exceeded 30%, oesophagectomy became the most cost effective option.

CONCLUSIONS

A strategy of endoscopic ablation provided the longest quality adjusted life expectancy for BO with HGD. Although endoscopic surveillance was less expensive than endoscopic ablation, it was associated with shorter survival. Optimal utilisation of healthcare resources may be achieved with endoscopic ablative therapy for BO with HGD.

Systematic review: the economic impact of irritable bowel syndrome

BACKGROUND

Although little mortality is associated with irritable bowel syndrome, curative therapy does not exist and thus the economic impact of this disorder may be considerable.

METHODS

A systematic review of the literature was performed. Studies were included if their focus was irritable bowel syndrome, and direct and/or productivity (indirect) costs were reported. Two investigators abstracted the data independently.

RESULTS

One hundred and seventy-four studies were retrieved by the search; 11 fulfilled all criteria for entry into the review. The mean direct costs of irritable bowel syndrome management were reported to be UK pound sterling90, Canadian$259 and US$619 per patient annually, with total annual direct costs related to irritable bowel syndrome of pound sterling45.6 million (UK) and $1.35 billion (USA). Direct resource consumption of all health care for irritable bowel syndrome patients ranged from US$742 to US$3166. Productivity costs ranged from US$335 to US$748, with total annual costs of $205 million estimated in the USA. Annual expenditure for all health care, in addition to expenditure limited to gastrointestinal disorders, was significantly higher in irritable bowel syndrome patients than in control populations.

CONCLUSIONS

Despite the lack of significant mortality, irritable bowel syndrome is associated with high direct and productivity costs. Irritable bowel syndrome patients consume more gastrointestinal-related and more total health care resources than non-irritable bowel syndrome controls, and sustain significantly greater productivity losses.

Systematic review: the economic impact of irritable bowel syndrome

BACKGROUND

Although little mortality is associated with irritable bowel syndrome, curative therapy does not exist and thus the economic impact of this disorder may be considerable.

METHODS

A systematic review of the literature was performed. Studies were included if their focus was irritable bowel syndrome, and direct and/or productivity (indirect) costs were reported. Two investigators abstracted the data independently.

RESULTS

One hundred and seventy-four studies were retrieved by the search; 11 fulfilled all criteria for entry into the review. The mean direct costs of irritable bowel syndrome management were reported to be UK pound sterling90, Canadian$259 and US$619 per patient annually, with total annual direct costs related to irritable bowel syndrome of pound sterling45.6 million (UK) and $1.35 billion (USA). Direct resource consumption of all health care for irritable bowel syndrome patients ranged from US$742 to US$3166. Productivity costs ranged from US$335 to US$748, with total annual costs of $205 million estimated in the USA. Annual expenditure for all health care, in addition to expenditure limited to gastrointestinal disorders, was significantly higher in irritable bowel syndrome patients than in control populations.

CONCLUSIONS

Despite the lack of significant mortality, irritable bowel syndrome is associated with high direct and productivity costs. Irritable bowel syndrome patients consume more gastrointestinal-related and more total health care resources than non-irritable bowel syndrome controls, and sustain significantly greater productivity losses.

Cost-effectiveness of colorectal cancer surveillance in ulcerative colitis

Key issues concerning colorectal cancer in inflammatory bowel disease include determination of the risk of colorectal cancer and assessment of interventions to increase survival. No randomized, controlled trials of colonoscopic surveillance compared to no surveillance exist; however, retrospective studies illustrate that surveillance is associated with improved survival, probably as a result of detection of cancer at earlier stages of disease. In the absence of prospective clinical trials of either prophylactic colectomy or surveillance colonoscopy to detect dysplasia, quantitative analysis has been utilized to estimate the impact of competing management strategies on costs and benefits. Published analyses show that while prophylactic colectomy will likely save the greatest number of life-years, quality of life is not optimal, and thus shared decision-making between provider and patient is recommended. Surveillance colonoscopy to detect early cancer and dysplasia appears to be cost-effective, although the risk of colorectal cancer must be substantial in order for this to hold true. It is estimated that the incidence of cancer in ulcerative colitis must exceed 27% over a 30-year period in order for surveillance colonoscopy every 2 years to be cost-effective. Determination of the optimal interval between surveillance procedures is also a contentious issue. Although annual surveillance colonoscopy may not be cost-effective, 3-4 year intervals yield cost-effectiveness ratios comparable to other medical practices deemed worthwhile by society, while 5-year interval produce an incremental cost-effectiveness similar to screening strategies in other diseases.

Step-down management of gastroesophageal reflux disease

BACKGROUND & AIMS

As the economic burden of gastroesophageal reflux disease (GERD) is largely weighted to maintenance as opposed to initial therapy, switching from more potent to less expensive medication once symptoms are alleviated (step-down therapy) may prove to be most cost-effective. This study aimed to prospectively evaluate the feasibility of step-down therapy in a cohort of patients with symptoms of uncomplicated GERD.

METHODS

Patients whose GERD symptoms were alleviated by proton pump inhibitors (PPIs) were recruited from outpatient general medicine clinics. After baseline demographic and quality of life information were obtained, PPIs were withdrawn from subjects in a stepwise fashion. Primary outcome was recurrence of symptoms during follow-up that required reinstitution of PPIs. Secondary outcomes included changes in quality of life and overall cost of management. Predictors of nonresponse to step-down were assessed.

RESULTS

Seventy-one of 73 enrolled subjects completed the study. Forty-one of 71 (58%) were asymptomatic off PPI therapy after 1 year of follow-up. Twenty-four of 71 (34%) required histamine 2-receptor antagonists, 5/71 (7%) prokinetic agents, 1/71 (1%) both, and 11/71 (15%) remained asymptomatic without medication. Quality of life did not significantly change, whereas management costs decreased by 37%. Multivariable analysis revealed younger age and a dominant symptom of heartburn to predict PPI requirement.

CONCLUSIONS

Step-down therapy is successful in the majority of patients and can decrease costs without adversely affecting quality of life.

Unsedated small-caliber esophagogastroduodenoscopy (EGD): less expensive and less time-consuming than conventional EGD

BACKGROUND

A significant portion of the costs and complications of esophagogastroduodenoscopy (EGD) are related to the use of sedation. The feasibility and tolerability of small-caliber EGD (scEGD) without sedation has been evaluated; however, there is limited data concerning times and costs associated with this procedure as compared with conventional EGD (cEGD) with sedation.

STUDY

Sixteen patients underwent scEGD with the Pentax EG-1840 (outside diameter, 6 mm) without sedation. A control group of 16 patients was matched for age, sex, day, and indication of procedure. The time of procedure, time in procedure room, time in recovery room, and procedure costs were determined in both the study and control groups. After the procedure, scEGD patients completed surveys consisting of visual-analogue scales to assess tolerance and preference regarding sedation for future procedures.

RESULTS

Procedure time, procedure room time, and recovery room time was 5.2, 16.3, and 9 minutes for scEGD and 13.5, 34.9, and 41.3 minutes for cEGD, respectively (p < 0.001 for all comparisons). The mean cost of scEGD, excluding physician fees, was $462.00, which was significantly lower than the $587.00 for cEGD (p < 0.001). Survey results revealed good tolerance for the unsedated procedure.

CONCLUSIONS

Unsedated scEGD was well tolerated and resulted in a shorter time of procedure, less time spent in procedure room, reduced recovery room time, and lower costs as compared with cEGD with sedation.

Lansoprazole treatment of patients with chronic idiopathic laryngitis: a placebo-controlled trial

OBJECTIVE

Previous uncontrolled studies suggested a therapeutic benefit for treating gastroesophageal reflux disease (GERD) among patients with laryngitis. The present study is the first randomized, placebo-controlled, double-blind study of gastric acid suppression among patients with laryngitis in the United States.

METHODS

Patients diagnosed with idiopathic chronic laryngitis were randomized to receive either lansoprazole 30 mg p.o. b.i.d. or a matching placebo for 3 months. Before randomization, all patients underwent upper endoscopy, dual probe ambulatory 24-h esophageal pH-metry, and laryngoscopy, as well as completing a symptom questionnaire for GERD and laryngitis. The primary outcome of treatment was the complete resolution of laryngeal symptoms.

RESULTS

A total of 22 patients with symptoms and signs of chronic laryngitis were enrolled, 20 of whom completed the study. At baseline, there were no significant differences between the two groups with regards to GERD symptoms, erosive esophagitis, proximal and distal esophageal pH-metry, or laryngeal signs and symptoms. In an intention-to-treat analysis, six patients in the lansoprazole group (50%) and only one patient (10%) in the placebo group achieved a complete symptomatic response, p = 0.04. Apart from receiving lansoprazole, there were no significant differences between responders and nonresponders in any of baseline esophageal or laryngeal signs and symptoms.

CONCLUSIONS

Empirical treatment with lansoprazole is efficacious in relieving symptoms of laryngitis compared to placebo. Such treatment can be considered as a first-line option in managing patients with idiopathic chronic laryngitis.

The laparoscopic evaluation of ascites

Laparoscopy is an invaluable technique for the evaluation of ascites in subgroups of patients with ascites. Indications for laparoscopic examination include determination of the causes of ascites when routine tests fail to disclose the source, evaluation for the presence of multiple causes of ascites formation, or histopathologic verification of malignancy within the peritoneal cavity. Several reported series have illustrated the efficacy of laparoscopy for the diagnosis of peritoneal carcinomatosis, tuberculous peritonitis, or unsuspected cirrhosis, securing its role in the management of selected patients with ascites.

Cost-effectiveness of colonoscopy in screening for colorectal cancer

BACKGROUND

Fecal occult blood testing, flexible sigmoidoscopy, and colonoscopy are used to screen patients for colorectal cancer.

OBJECTIVE

To compare the cost-effectiveness of fecal occult blood testing, flexible sigmoidoscopy, and colonoscopy.

DESIGN

The cost-effectiveness of the three screening strategies was compared by using computer models of a Markov process. In the model, a hypothetical population of 100 000 persons 50 years of age undergoes annual fecal occult blood testing, sigmoidoscopy every 5 years, or colonoscopy every 10 years. Positive results on fecal occult blood testing or adenomatous polyps found during sigmoidoscopy are worked up by using colonoscopy. After polypectomy, colonoscopy is repeated every 3 years until no polyps are found.

DATA SOURCES

Transition rates were estimated from U.S. vital statistics and cancer statistics and from published data on the sensitivity, specificity, and efficacy of various screening techniques. Costs of screening and cancer care were estimated from Medicare reimbursement data.

TARGET POPULATION

Persons 50 years of age in the general population.

TIME HORIZON

The study population was followed annually until death.

PERSPECTIVE

Third-party payer.

OUTCOME MEASURE

Incremental cost-effectiveness ratio.

RESULTS OF BASE-CASE ANALYSIS

Compared with colonoscopy, annual screening with fecal occult blood testing costs less but saves fewer life-years. A screening strategy based on flexible sigmoidoscopy every 5 or 10 years is less cost-effective than the other two screening methods.

RESULTS OF SENSITIVITY ANALYSIS

Screening with fecal occult blood testing is more sensitive to changes in compliance rates, and it becomes easily dominated by colonoscopy under most conditions assuming less than perfect compliance. Other assumptions about the sensitivity and specificity of fecal occult blood testing, screening frequency, efficacy of colonoscopy in preventing cancer, and polyp incidence have a lesser influence on the differences in cost-effectiveness between colonoscopy and fecal occult blood testing.

CONCLUSIONS

Colonoscopy represents a cost-effective means of screening for colorectal cancer because it reduces mortality at relatively low incremental costs. Low compliance rates render colonoscopy every 10 years the most cost-effective primary screening strategy for colorectal cancer.

The impact of colorectal cancer screening on life expectancy

METHODS

The purpose of this study was to assess the effect of screening for colorectal cancer on life expectancy and estimate the number of colonoscopies needed per life year saved. The declining exponential approximation of life expectancy was used to calculate the effect of colorectal cancer screening on expected remaining lifetime. The annual number of deaths from colorectal cancer and the size of the population were obtained from the vital statistics of the United States. Published reports were consulted to determine the decrease in mortality from colorectal cancer achieved by fecal occult blood testing, screening sigmoidoscopy or colonoscopy. A Markov chain analysis was used to determine the endoscopic resources required to screen and survey the entire population of U.S. residents age 50 years until death or age 85 years.

RESULTS

Colorectal cancer decreases the life expectancy of U.S. residents aged 50 to 54 years by 292 days and those aged 70 to 74 years by 70 days. Screening with fecal occult blood tests extends expected lifetime of the 2 age groups by 51 and 12 days, respectively, whereas screening with sigmoidoscopy leads to increases of 86 and 21 days. Colonoscopic screening increases expected lifetime by 170 and 41 days, respectively. The number of colonoscopies needed to save 1 year of expected life ranges from 2.9 to 6.0, depending on the type of screening regimen used.

CONCLUSIONS

The extension of life through screening colonoscopy is two or three times longer than the extension achieved through flexible sigmoidoscopy or fecal occult blood test, respectively. Although a large number of colonoscopies are required to screen the U.S. population, relatively few colonoscopies need to be invested per year of life expectancy saved.

Screening for hereditary hemochromatosis in siblings and children of affected patients. A cost-effectiveness analysis

BACKGROUND

Screening for hereditary hemochromatosis is traditionally done by using serum iron studies. However, mutation analysis of the hemochromatosis-associated HFE gene has recently become available.

OBJECTIVE

To compare the cost-effectiveness of no screening with four screening strategies that incorporate HFE gene testing or serum iron studies.

DESIGN

Cost-effectiveness analysis.

DATA SOURCES

Published literature.

TARGET POPULATION

Siblings and children of an affected proband.

TIME HORIZON

Lifetime from 10 years of age (children) or 45 years of age (siblings).

PERSPECTIVE

Societal.

INTERVENTION

1) Serum iron studies. 2) Gene testing of the proband. If the proband is homozygous (C82Y+/+), the spouse undergoes gene testing; if he or she is heterozygous (C82Y+/-), the children undergo gene testing. 3) Gene testing of the proband; if he or she is homozygous, relatives undergo gene testing. 4) Direct gene testing of relatives.

OUTCOME MEASURES

Cost per life-year saved and incremental cost-effectiveness ratio.

RESULTS OF BASE-CASE ANALYSIS

In children, HFE gene testing of the proband was the most cost-effective strategy for screening one child (incremental cost-effectiveness ratio, $508 per life-year saved). HFE gene testing of the proband followed by testing of the spouse was the most cost-effective strategy for screening two or more children (incremental cost-effectiveness ratio, $3665 per life-year saved). In siblings, all screening strategies were dominant compared with no screening. Strategies using HFE gene testing were less costly than serum iron studies.

RESULTS OF SENSITIVITY ANALYSIS

Despite varying the prevalence of mutations and regardless of the cost of the genetic test in one- and two-way sensitivity analyses, HFE gene testing remained cost-effective.

CONCLUSIONS

HFE gene testing for the C282Y mutation is a cost-effective method of screening relatives of patients with hereditary hemochromatosis.

Economic analysis of step-wise treatment of gastro-oesophageal reflux disease

BACKGROUND

To expose patients with gastro-oesophageal reflux disease (GERD) to the least amount of medication and to reduce health expenditures, it is recommended that their treatment is started with a small dose of an antisecretory or prokinetic medication. If patients fail to respond, the dose is increased in several consecutive steps or the initial regimen is changed to a more potent medication until the patients become asymptomatic. Although such treatment strategy is widely recommended, its impact on health expenditures has not been evaluated.

METHODS

The economic analysis compares the medication costs of competing medical treatment strategies, using two different sets of cost data. Medication costs are estimated from the average wholesale prices (AWP) and from the lowest discount prices charged to governmental health institutions. A decision tree is used to model the step-wise treatment of GERD. In a Monte Carlo simulation, all transition probabilities built into the model are varied over a wide range. A threshold analysis evaluates the relationship between the cost of an individual medication and its therapeutic success rate.

RESULTS

In a governmental health care system, a step-wise strategy saves on average $916 per patient every 5 years (range: $443-$1628) in comparison with a strategy utilizing only the most potent medication. In a cost environment relying on AWP, the average savings amount to $256 (-$206 to +$1561). The smaller the cost difference between two consecutive treatment steps, the longer one needs to follow the patients to reap the benefit of the small cost difference. However, even a small cost difference can turn into tangible cost savings, if a large enough fraction of GERD patients responds to the initial step of a less potent but also less expensive medication.

CONCLUSIONS

The economic analysis suggests that a step-wise utilization of increasingly more potent and more expensive medications to treat GERD would result in appreciable cost savings.

Corpus gastritis is protective against reflux oesophagitis

BACKGROUND

Gastric acid is important in the pathogenesis of reflux oesophagitis. Acid production by the gastric corpus is reduced in corpus gastritis.

AIMS

To determine whether corpus gastritis protects against reflux oesophagitis.

METHODS

Patients presenting for elective oesophagogastroduodenoscopy were studied. Two biopsy specimens were taken from the antrum, corpus, and cardia and stained with haematoxylin/eosin and Diff-Quick II stains. The presence and severity of gastritis were graded according to a modified updated Sydney classification.

RESULTS

Of 302 patients, 154 had endoscopic signs of reflux oesophagitis. There was no difference between patients with and controls without oesophagitis in the overall infection rates with Helicobacter pylori. Acute or chronic corpus gastritis occurred less often in patients with than those without reflux oesophagitis. Compared with controls, corpus gastritis was less severe in patients with reflux oesophagitis. The presence of acute or chronic gastritis in the corpus was significantly correlated with either type of gastritis in other areas of the stomach. In a multivariate logistic regression, age, sex, smoking status, and the presence of chronic corpus gastritis all exerted a significant influence on the presence of reflux oesophagitis. Chronic corpus gastritis was associated with a 54% reduced risk for reflux oesophagitis.

CONCLUSIONS

While infection with H pylori alone may not affect the occurrence of reflux oesophagitis, the development of chronic corpus gastritis seems to be protective.

Reliability block diagrams to model disease management

BACKGROUND AND OBJECTIVES

Studies of diagnostic or therapeutic procedures in the management of any given disease tend to focus on one particular aspect of the disease and ignore the interaction between the multitude of factors that determine its final outcome. The present article introduces a mathematical model that accounts for the joint contribution of various medical and non-medical components to the overall disease outcome.

METHODS

A reliability block diagram is used to model patient compliance, endoscopic screening, and surgical therapy for dysplasia in Barrett's esophagus.

RESULTS

The overall probability of a patient with a Barrett's esophagus to comply with a screening program, be correctly diagnosed with dysplasia, and undergo successful therapy is 37%. The reduction in the overall success rate, despite the fact that the majority of components are assumed to function with reliability rates of 80% or more, is a reflection of the multitude of serial subsystems involved in disease management. Each serial component influences the overall success rate in a linear fashion. Building multiple parallel pathways into the screening program raises its overall success rate to 91%. Parallel arrangements render systems less sensitive to diagnostic or therapeutic failures.

CONCLUSIONS

A reliability block diagram provides the means to model the contributions of many heterogeneous factors to disease outcome. Since no medical system functions perfectly, redundancy provided by parallel subsystems assures a greater overall reliability.

Reliability block diagrams to model the management of colorectal cancer

The present study aims to show how various medical and nonmedical components contribute to success and failure in the management of colorectal cancer. The first encounter, subsequent diagnosis, and surgical therapy of a patient with Dukes B sigmoid cancer is modeled as a reliability block diagram with a serial and parallel arrangement of various components. The overall probability of a patient with new-onset colorectal cancer to visit a physician, be correctly diagnosed, and undergo successful therapy is 69%. The reduction in the overall success, despite the fact that the majority of components are assumed to function with failure rates of 5% or less, is a reflection of the multitude of serial subsystems involved in the management of the patient. In contrast, the parallel arrangement of subsystems results in a relative insensitivity of the overall system to failure, a greater stability, and an improved performance. Since no medical system functions perfectly, redundancy associated with parallel subsystems assures a better overall outcome. System analysis of health care provides a means to improve its performance.

The impact of peptic ulcer disease and infection with Helicobacter pylori on life expectancy

OBJECTIVE

Knowledge about the influence of H. pylori-related disease on life expectancy might affect physician behavior in dealing with such disease. The aim of this study was to assess how life expectancy is influenced by H. pylori infection and peptic ulcer disease.

METHODS

The declining exponential approximation of life expectancy was used to model the effects of H. pylori and various peptic ulcer disease conditions on life expectancy. Deaths from peptic ulcer and gastric cancer were determined from the Vital Statistics of the United States. H. pylori prevalence rates were derived from the existing literature.

RESULTS

Cure of active peptic ulcer increases life expectancy by 2.3 yr in persons aged 40-44 yr and 121 days in persons aged 70-74 yr. More substantial impact occurs in complicated ulcer, with increases in life expectancy ranging between 26.1 and 6.3 yr. Primary prevention of H. pylori could increase life expectancy by 190 days in those aged 40-44 yr and 26 days in 70-74-yr-old subjects.

CONCLUSION

The benefit of ulcer cure or H. pylori prevention diminishes as age advances. Cure of ulcers in young patients or in those who have sustained complications results in an appreciable increase in life expectancy. Successful primary prevention of H. pylori in selected populations could substantially increase life expectancy.

Review article: Medical decision models of Helicobacter pylori therapy to prevent gastric cancer

The aim of the present article is to study the utility of Helicobacter pylori eradication programmes in decreasing the incidence of gastric cancer. Three types of decision models are employed to pursue this aim, i.e. decision tree, present value, and declining exponential approximation of life expectancy (DEALE). 1) A decision tree allows one to model the interaction of multiple variables in great detail and to calculate the marginal cost, as well as the marginal cost-benefit ratio, of a preventive strategy. The cost of gastric cancer, the efficacy of H. pylori therapy in preventing cancer, and the cumulative probability of developing gastric cancer exert the largest influence on the marginal cost of cancer prevention. The high cost of future gastric cancer and a high efficacy of therapy make screening for H. pylori and its eradication the preferred strategy. 2) The present value is an economic method to adjust future costs or benefits to their current value using a discount rate and the length of time between now and a given time point in the future. It accounts for the depreciation of money and all material values over time. During childhood, the present value of future gastric cancer is very low. Vaccination of children to prevent gastric cancer would need to be very inexpensive to be practicable. Cancer prevention becomes a feasible option, only if the time period between the preventive measures and the occurrence of gastric cancer can be made relatively short. 3) The DEALE provides a means to calculate the increase in life expectancy that would occur, if death from a particular disease became preventable. Life expectancy of the general population is hardly affected by gastric cancer. For life expectancy to increase appreciably by vaccination or antibiotic therapy directed against H. pylori infection, these interventions would need to be focused towards a sub-population with an a priori high risk for gastric cancer.