W M Wong

Peking University, Peping, Beijing, China

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Publications (56)336.47 Total impact

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    ABSTRACT: Gastro-oesophageal reflux disease and irritable bowel syndrome are common diseases which may be related. To examine the association between gastro-oesophageal reflux disease and irritable bowel syndrome in Chinese population in Hong Kong. Randomly selected ethnic Chinese were invited to participate in a telephone survey in 1996. Gastro-oesophageal reflux disease was defined as subjects having heartburn and/or acid regurgitation once weekly or more. Irritable bowel syndrome was diagnosed according to the Rome I criteria. The association between gastro-oesophageal reflux disease and irritable bowel syndrome was calculated using a statistical model which allows the odds ratio to be measured. One thousand six hundred and forty-nine subjects completed the interview (response rate 62%). The population prevalence of gastro-oesophageal reflux disease and irritable bowel syndrome were 5% and 4%, respectively. Thirteen per cent of subjects with gastro-oesophageal reflux disease and 11% with irritable bowel syndrome suffered from both gastro-oesophageal reflux disease and irritable bowel syndrome. The OR of having gastro-oesophageal reflux disease and irritable bowel syndrome together was estimated to be 3 (95% CI: 1.05, 6.27) indicating a positive association between the two diseases. This association occurred predominantly in male subjects [OR = 9.3, (95% CI: 2.3, 26.2)] but not as strong in females [OR = 1.5, (95% CI: 0.3, 4.3)]. Younger subjects were statistically more prone to the two diseases. There is a positive association between gastro-oesophageal reflux disease and irritable bowel syndrome, and their association occurs predominantly in male subjects.
    Alimentary Pharmacology & Therapeutics 06/2007; 25(9):1099-104. DOI:10.1111/j.1365-2036.2007.03304.x
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    ABSTRACT: To investigate the optimal strategy to treat dyspeptic patients in primary care. Dyspeptic patients presenting to primary care outpatient clinics were randomly assigned to: (1) empirical endoscopy, (2) H pylori test-and-treat, and (3) empirical prokinetic treatment with cisapride. Early endoscopy was arranged if patients remained symptomatic after 2 wk. Symptom severity, quality-of-life (SF-36) as well as patient preference and satisfaction were assessed. All patients underwent endoscopy by wk 6. Patients were followed up for one year. Two hundred and thirty four patients were recruited (163 female, mean age 49). 46% were H pylori positive. 26% of H pylori tested and 25% of empirical prokinetic patients showed no improvement at wk 2 follow-up and needed early endoscopy. 15% of patients receiving empirical cisapride responded well to treatment but peptic ulcer was the final diagnosis. Symptom resolution and quality-of-life were similar among the groups. Costs for the three strategies were HK dollar 4343, dollar 1771 and dollar 1750 per patient. 66% of the patients preferred to have early endoscopy. The three strategies are equally effective. Empirical prokinetic treatment was the least expensive but peptic ulcers may be missed with this treatment. The H pylori test-and-treat was the most cost-effective option.
    World Journal of Gastroenterology 09/2006; 12(31):5010-6.
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    ABSTRACT: To test the efficacy of levofloxacin-based second-line therapy for resistant Helicobacter pylori infection. One hundred and six patients who failed H. pylori eradication were randomized to receive (i) lansoprazole 30 mg, amoxicillin 1 g, levofloxacin 500 mg, all given twice daily for 7 days (LAL); or (ii) lansoprazole 30 mg twice daily, metronidazole 400 mg thrice daily, bismuth subcitrate 120 mg and tetracycline 500 mg four times daily for 7 days (quadruple). Post-treatment H. pylori status was determined by (13)C-urea breath test. Intention-to-treat and per-protocol H. pylori eradication rates were 57/60% for the LAL group and 71/76% for the quadruple group respectively. Metronidazole, clarithromycin, amoxicillin and levofloxacin resistance were found in 76%, 71%, 0% and 18% of patients, respectively. Levofloxacin resistance led to treatment failure in the LAL group. For patients with dual resistance to metronidazole and clarithromycin, the eradication rates were 79% in the LAL group (levofloxacin-sensitive) and 65% in the quadruple group (P=0.34). Lansoprazole, amoxicillin plus levofloxacin second-line therapy is comparable with quadruple therapy in efficacy. Subjects, especially those with dual resistance to metronidazole and clarithromycin, may consider levofloxacin-based therapy for levofloxacin-sensitive strains.
    Alimentary Pharmacology & Therapeutics 03/2006; 23(3):421-7. DOI:10.1111/j.1365-2036.2006.02764.x
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    ABSTRACT: To determine the antibiotic susceptibility of Helicobacter pylori and evaluate the efficacy of a clarithromycin-based triple therapy in relation to antibiotic resistance. Consecutive patients referred for upper endoscopy due to dyspeptic symptoms were recruited. Gastric biopsies were obtained for the CLO test, histology and culture. Antibiotic susceptibility was assessed by the E-test. Patients with H. pylori infection received rabeprazole 20 mg, clarithromycin 500 mg, and amoxicillin 1,000 mg, all twice daily for 7 days. Of 234 patients recruited, 124 were H. pylori-positive and culture was successful in 102 patients. The updated prevalences of resistance to clarithromycin, amoxicillin and metronidazole were 7.8, 0 and 39.2%, respectively. A total of 86 patients received 1-week triple therapy with rabeprazole 20 mg, clarithromycin 500 mg, and amoxicillin 1,000 mg, all twice daily, and 81 patients attended the follow-up test. Eradication rates by per-protocol and intention-to-treat analysis were 92.6 and 87.2%, respectively. The eradication rate by per protocol was significantly higher in patients with clarithromycin-susceptible strains than in those with clarithromycin-resistant strains (98.6 vs. 28.6%, p < 0.001). Clarithromycin resistance reduces the clinical efficacy of clarithromycin-based triple therapy. However, due to the low prevalence of clarithromycin resistance, clarithromycin-based therapy is still the first choice for clinical use.
    Digestion 02/2006; 73(2-3):101-6. DOI:10.1159/000094040
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    ABSTRACT: Colorectal cancer is the second commonest cancer in Hong Kong. The screening behaviour of the Chinese population has not been assessed. The aim of this study is to report a pilot study of educating and subsequent evaluation of colorectal cancer screening behaviour in the Hong Kong Chinese population. Subjects were invited to attend a free health talk on colorectal cancer. Both self-paid faecal occult blood testing (FOBT) and free screening colonoscopy were offered after the education programme. Of the participants taking part in the education programme 113/119 (95%) completed the FOBT. Of the FOBT 8/113 (7%) showed positive result and three patients had neoplasia at colonoscopy. Twenty-five patients with negative FOBT also completed colonoscopy; two had adenomas. Screening colonoscopy after FOBT was accepted by 28% of subjects. Those younger than 65 years and those with a positive FOBT (7/8 versus 25/105 for those with negative FOBT, P=0.0003) were more likely to agree to screening colonoscopy. In conclusion, health education is important for ensuring high acceptance and implementation of colorectal cancer screening in Hong Kong Chinese. FOBT is an acceptable and feasible screening method in Hong Kong.
    European Journal of Cancer Prevention 05/2005; 14(2):181-4. DOI:10.1097/00008469-200504000-00015
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    ABSTRACT: Recent studies suggest that the Helicobacter pylori eradication rate in patients with non-ulcer dyspepsia is lower when compared to patients with peptic ulcer diseases. The aim of this study was to study the efficacy of triple therapy for H. pylori infection in patients with duodenal ulcer vs. patients with non-ulcer dyspepsia. A total of 582 Chinese patients with proven H. pylori infection were recruited to receive: omeprazole 20 mg, amoxicillin 1000 mg and clarithromycin 500 mg all given twice daily for 7 days (OCA regime). Endoscopy with rapid urease test, histology and culture were performed before treatment. Post-treatment H. pylori status was determined by (13)C-urea breath test. Metronidazole, clarithromycin and amoxicillin resistance was defined as minimum inhibitory concentration (MIC) of >8 microg/mL, >1 microg/mL and >1 microg/mL, respectively. A significantly higher (intention-to-treat/per-protocol) eradication rate was found in patients with duodenal ulcer than those with non-ulcer dyspepsia (91/94% vs. 84/88% respectively, P = 0.011 and P = 0.016). Clarithromycin resistance rate was higher in patients with non-ulcer dyspepsia than those with duodenal ulcer (14% vs. 6%, P = 0.015). Clarithromycin resistance (40% vs. 5%, P < 0.001, OR 12, 95% CI: 5.7-24.3) and the diagnosis of non-ulcer dyspepsia (91% vs. 84%, P = 0.011, OR 2.0, 95% CI: 1.2-3.3) significantly affected the success of H. pylori eradication. Clarithromycin resistance accounts for the significantly lower and suboptimal H. pylori eradication rate of OCA regimen in Chinese patients with non-ulcer dyspepsia compared to those with duodenal ulcer.
    Alimentary Pharmacology & Therapeutics 01/2005; 21(1):73-81. DOI:10.1111/j.1365-2036.2004.02283.x
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    ABSTRACT: The natural history of gastro-oesophageal reflux disease in Asian population has not been studied before. To study the onset and disappearances of reflux symptoms over a 1-year period in the Chinese population. A population-based telephone survey was performed in 2002 and repeated 1 year later. The change in prevalence rate, onset and disappearance of gastro-oesophageal reflux disease, and the change in diagnoses were assessed. Factors associated with the onset and disappearance of gastro-oesophageal reflux disease were studied. A total of 712 subjects completed the first and second survey. The annual, monthly and weekly prevalence of gastro-oesophageal reflux disease were 34.1%, 10.1% and 2.7% respectively. The onset rate (per 1000 person-year) and disappearance rate of any gastro-oesophageal reflux disease and frequent gastro-oesophageal reflux disease (> or = monthly symptoms) were 209, 40; and 395, 243 respectively. Forty-four percentage of gastro-oesophageal reflux disease subjects changed their diagnoses in 2003. By multiple logistic regression analysis, high anxiety score (OR: 1.2, 95% CI: 1.1-1.2) and higher educational level (OR: 2.7, 95% CI: 1.3-6.3) were associated with the onset of gastro-oesophageal reflux disease; while the frequency of acid regurgitation (OR: 0.35, 95% CI: 0.17-0.70) and use of antisecretory therapy (OR: 0.50, 95% CI: 0.28-0.89) were associated with the disappearance of gastro-oesophageal reflux disease. The prevalence of gastro-oesophageal reflux disease is stable over 1 year. Higher anxiety score and higher educational level were associated with the onset of gastro-oesophageal reflux disease, while lower frequency of reflux symptoms and infrequent use of antisecretory therapy were associated with the disappearance of gastro-oesophageal reflux disease in a Chinese population.
    Alimentary Pharmacology & Therapeutics 11/2004; 20(7):803-12. DOI:10.1111/j.1365-2036.2004.02198.x
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    ABSTRACT: BACKGROUND Transient lower esophageal sphincter relaxation (TLESR) is the major mechanism for AND AIMS: gastroesophageal reflux in the Western population. The major reflux mechanism in Chinese patients with GERD has not been studied before. METHODS: Fifty-four patients with GERD and 28 controls underwent stationary baseline manometry and the 24-h ambulatory esophageal pH monitoring. TLESRs were measured before and after an 850 kcal meal in the supine position. Primary peristalsis, secondary peristalsis, and esophageal acid clearance were measured by esophageal manometry. RESULTS: Total time esophageal pH less than or equal to 4 (7.3 vs 1.5, p = 0.001) was significantly higher in patients with GERD when compared to controls. Majority of acid reflux episodes was due to TLESR in both patients with GERD and controls. The frequency of TLESRs after meal was similar between patients with GERD and controls (1.0 vs 1.3/h, p = 0.34). There was no difference in the distribution of reflux mechanism between patients with GERD and controls. However, patients with GERD had a significantly lower successful primary peristalsis (59% vs 70%, p = 0.043) when compared to controls. CONCLUSION: The frequency of TLESRs was similar between patients with GERD and controls during stationary manometry. Primary peristalsis was impaired in Chinese patients with GERD. Esophageal motor dysfunction may contribute to the pathophysiology of GERD in the Chinese population.
    The American Journal of Gastroenterology 11/2004; 99(11):2088-2093. DOI:10.1117/j.1572-0241.2004.30417.x
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    Journal of Gastroenterology and Hepatology 11/2004; 19(10):1213. DOI:10.1111/j.1440-1746.2004.03620.x
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    ABSTRACT: We previously reported that aspirin inhibited Helicobacter pylori growth and suppressed the mutagenic effect of metronidazole. To determine the effects of a cyclo-oxygenase (COX)-2-specific inhibitor, SC-236, and a non-selective COX inhibitor, indometacin, on the growth, urease activity and antimicrobial susceptibility of H. pylori. Three H. pylori reference strains, and 18 clinical isolates were treated with SC-236 or indometacin for 24 and 48 h. Growth, urease activity and susceptibility to clarithromycin and metronidazole of the bacteria were assessed by viable colony counting, spectrophotometry and E-test respectively. SC-236 and indometacin inhibited H. pylori growth in a dose-dependent manner with the lowest inhibitory concentrations of 0.03 and 0.1 mm, and the lethal concentrations of 0.09 and 0.3 mm, respectively. The numbers of CFU/mL in Brucella broth containing 0.09 mm SC-236 were 2 log lower at 24 h, and even 3 log lower at 48 h than that at 0 h (P = 0.035, compared with the vehicle control). Treatment of 0.3 mm indometacin reduced the number of CFU/mL by 1 log at 24 h compared with that at 0 h (P = 0.037 compared with the vehicle control). Helicobacter pylori urease activity began to decrease with 0.06 mm SC-236 at 24 h (P = 0.016), and 0.3 mm indometacin at 48 h (P = 0.025). MICs of metronidazole and clarithromycin against H. pylori were decreased significantly in the presence of 0.03 mm SC-236 or 0.1 mm indometacin (all P < 0.001). Both SC-236 and indometacin suppressed the growth and urease activity of H. pylori in a dose-dependent manner, and increased its susceptibility to the antibiotics.
    Alimentary Pharmacology & Therapeutics 09/2004; 20(6):675-81. DOI:10.1111/j.1365-2036.2004.02168.x
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    W M Wong, W H C Hu, K C Lai
    Journal of Gastroenterology and Hepatology 08/2004; 19(7):829. DOI:10.1111/j.1440-1746.2004.03558.x
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    ABSTRACT: To determine gastric expression of trefoil family factor 2 (TFF2) and MUC6 in Helicobacter pylori positive and negative subjects, and its association with antralisation at the gastric incisura. Gastric biopsies from the antrum, incisura, and body of 76 dyspeptic patients without ulcers were used for the determination of H. pylori infection, histological changes, and epithelial TFF2 and MUC6 expression. In the foveola, the rates of TFF2 and MUC6 immunostaining were greater in H. pylori infected (n = 27) than in uninfected patients (n = 49) at the antrum (59.3% v 4.1% for TFF2 and 63.0% v 4.1% for MUC6; both p < 0.001) and incisura (44.4% v 2.0% for TFF2 and 48.1% v 0% for MUC6; both p < 0.001). In the deeper glands, the rates were also greater in H. pylori infected than in uninfected patients at the incisura (85.2% v 22.4% for both TFF2 and MUC6; p < 0.001). Antral-type mucosa was present at the incisura in 28 of the 76 patients. TFF2 and MUC6 expression in the foveola and deeper glands was significantly associated with antral-type mucosa, independent of H. pylori status. Helicobacter pylori infection increases the expression of TFF2 and MUC6 in the gastric epithelium. Aberrant TFF2 and MUC6 expression is associated with antralisation of gastric incisura.
    Journal of Clinical Pathology 08/2004; 57(8):861-6. DOI:10.1136/jcp.2003.015487
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    ABSTRACT: Endoscopic sphincterotomy (ES) or cholecystectomy can prevent recurrent acute pancreatitis (RAP) in patients with gallstone-related pancreatitis. However, it is unknown whether cholecystectomy after ES offers additional benefit in preventing RAP in these patients. This is a retrospective study to assess whether cholecystectomy can decrease the incidence of RAP in patients with gallstone-related pancreatitis. Records from 139 patients with gallstone-related pancreatitis were analyzed. Of these, 58 patients had gallbladder stones with concomitant common bile duct (CBD) stones and 81 patients had gallbladder stones without CBD stones. Of the 58 patients who had both gallbladder and CBD stones, 37 (63.8 %) did not undergo cholecystectomy after ES (group 1) and 21 patients (36.2 %) did undergo cholecystectomy after ES (group 2). Of the 81 patients who had gallbladder stones but who did not have CBD stones, 54 (66.7 %) did not undergo cholecystectomy (group 3) and 27 (33.3 %) did undergo cholecystectomy (group 4). At the time of analysis, three patients (8.1 %) in group 1 and three patients (14.3 %) in group 2 developed RAP. There was no significant difference in the estimated probability of occurrence of RAP over time between group 1 and group 2 ( P = 0.41). However, there was a significantly higher probability of patients developing RAP over time in group 3 compared with group 4 (6/54 vs. 0/27 respectively, P = 0.04). In patients with gallbladder stones without CBD stones, cholecystectomy can decrease the incidence of RAP. In patients with both gallbladder and CBD stones, however, the risk of RAP was not further reduced by cholecystectomy after ES and complete removal of CBD stones.
    Endoscopy 04/2004; 36(3):206-11. DOI:10.1055/s-2004-814249
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    ABSTRACT: Previous studies have suggested that the acid secretory capacity of the Chinese population is lower than that of the Western population. To compare the effect of lansoprazole 30 mg and 15 mg once daily on the 24-h oesophageal and intragastric pH profiles in Chinese patients with gastro-oesophageal reflux disease. Forty-four patients (male to female ratio, 27 : 17; mean age, 53 years; 55% with oesophagitis) with gastro-oesophageal reflux disease were randomized to receive lansoprazole 30 mg or 15 mg once daily for 4 weeks. Measurement of the 24-h oesophageal and intragastric pH, gastro-oesophageal reflux disease symptoms and quality of life was performed at baseline and during the last week of each dosing period. Lansoprazole 30 mg maintained an intragastric pH > 4 for 10.5 h vs. 9.6 h for lansoprazole 15 mg (P = 0.44). The percentage total time at oesophageal pH < 4 was similar for lansoprazole 30 mg and 15 mg (2.0% vs. 2.3%, P = 0.30). The proportion of patients with complete cure of heartburn and acid regurgitation and the quality of life assessment were similar for lansoprazole 30 mg and 15 mg. Both dosages of lansoprazole were well tolerated and the compliance was 100% in both groups. Lansoprazole dosages of 30 mg and 15 mg once daily provide a satisfactory decrease for oesophageal acid exposure and are equally effective for the treatment of gastro-oesophageal reflux disease in the Chinese population.
    Alimentary Pharmacology & Therapeutics 03/2004; 19(4):455-62. DOI:10.1046/j.1365-2036.2004.01846.x
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    ABSTRACT: Evaluar la incidencia de cáncer gástrico tras la erradicación de Helicobacter pylori.DiseñoEstudio prospectivo, aleatorizado, controlado con placebo.EmplazamientoProvincia de Fujian (China).Población a estudioReclutamiento poblacional (n = 2.423), con seguimiento de 7,5 años, mediante un cuestionario dietético/estilo de vida, analítica sanguínea, endoscopia, serología y biopsias gástricas para Helicobacter pylori. Criterios de exclusión por edad (< 35 o > 65 años), enfermedad concomitante grave, historia previa de erradicación de Helicobacter pylori o hallazgo de lesiones ulcerosas.IntervenciónEstudio de prevención primaria (n = 1.630 portadores sanos de Helicobacter pylori), aleatorizando a un grupo erradicador (n = 817) con omeprazol (20 mg/12 h) amoxicilina-ácido clavulánico (750 mg/12 h) y metronidazol (400 mg/12 h), y grupo placebo (n = 813). Enmascaramiento en 4 niveles: endoscopia, evolución clínica, análisis histológico y revisión terapéutica.Medición resultadoObjetivo principal: incidencia de cáncer gástrico (CG) durante el seguimiento comparando erradicación de Helicobacter pylori frente a placebo. Objetivo secundario: evaluar la incidencia de CG en sujetos con/sin lesiones precancerosas, comparando ambos grupos.ResultadosCáncer gástrico en 18 casos (el 1,1%; 147,2/100.000 persona- año); 7 casos corresponden al grupo erradicador (0,86%) y 11 al grupo placebo (1,35%). La incidencia acumulada de CG no mostró diferencias estadísticamente significativas entre ambos grupos (p = 0,33; test de rangos logarítmicos). Las variables diferenciales al inicio del estudio (alcohol, pescado, fruta) no tuvieron un efecto final sobre los resultados, mientras que el tabaco y la edad mostraban un mayor riesgo asociado (análisis de regresión Cox). De los 18 casos de CG, 6 se hallaron en sujetos sin lesión precancerosa y 12 en sujetos con lesión subyacente (7 del grupo erradicador y 5 en el placebo). En el análisis post-hoc, la erradicación de Helicobacter pylori en sujetos con lesión precancerosa mostró una reducción significativa de incidencia de CG comparado con placebo (p = 0,2, análisis Kaplan-Meier, test de rangos logarítmicos).ConclusiónLa incidencia de cáncer gástrico en población de alto riesgo muestra cifras similares tras una terapia erradicadora frente a Helicobacter pylori o placebo. En el subgrupo de portadores de Helicobacter pylori sin lesión precancerosa, la erradicación se acompaña de reducción del desarrollo de CG.
    FMC - Formación Médica Continuada en Atención Primaria 01/2004; 11(6):361. DOI:10.1016/S1134-2072(04)76147-2
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    ABSTRACT: To study whether prophylaxis with lansoprazole could prevent relapse of ulcers after eradication of Helicobacter pylori in patients with NSAID-related peptic ulcers. Patients who presented with peptic ulcers and were found to be infected with H. pylori while receiving NSAIDs were recruited into the study. They received, twice daily, lansoprazole 30 mg, amoxicillin 1 g and clarithromycin 500 mg for 1 week, followed by lansoprazole 30 mg daily for 4 weeks. Patients with healed ulcers and H. pylori eradicated were given naproxen 750 mg daily, and randomly assigned to receive lansoprazole 30 mg daily or no treatment for 8 weeks. The primary endpoint was the cumulative recurrence of symptomatic and complicated ulcers. At the end of the 8-week treatment period, significantly fewer patients (1/22, 4.5%, 95% confidence interval [CI] 0-23) in the lansoprazole group compared with the group that received H. pylori eradication alone (9/21, 42.9%, 95% CI 22-66) developed recurrence of symptomatic and complicated ulcers (log rank test P=0.0025). Lansoprazole significantly reduced the cumulative relapse of symptomatic and complicated ulcers in patients requiring NSAIDs after eradication of H. pylori.
    Alimentary Pharmacology & Therapeutics 11/2003; 18(8):829-36. DOI:10.1046/j.1365-2036.2003.01762.x
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    ABSTRACT: Colorectal cancer screening by guaiac faecal occult blood test has been shown to reduce the incidence and mortality of colorectal cancer in Western populations. The optimal faecal occult blood test, whether guaiac or immunochemical, for colorectal cancer screening in the Chinese population remains to be defined. To compare the performance characteristics of a sensitive guaiac-based faecal occult blood test (Hemoccult SENSA) and an immunochemical faecal occult blood test (FlexSure OBT) in a Chinese population referred for colonoscopy. One hundred and thirty-five consecutive patients who were referred for colonoscopy and who met the study inclusion criteria took samples for the two faecal occult blood tests simultaneously from three successive stool specimens, with no dietary restrictions. All tests were developed and interpreted by a single experienced technician who was blind to the clinical diagnosis. The sensitivity, specificity and positive predictive value for the detection of colorectal adenomas and cancers were estimated for the two tests. The sensitivity, specificity and positive predictive value for the detection of significant colorectal neoplasia (adenomas > or = 1.0 cm and cancers) were 91%, 70% and 18% for Hemoccult SENSA and 82%, 94% and 47% for FlexSure OBT. The specificity and positive predictive value were significantly higher for FlexSure OBT than for Hemoccult SENSA (P < 0.001 and P = 0.016, respectively). Combining the positive results from both faecal occult blood tests did not improve the accuracy. The positive predictive value of the immunochemical faecal occult blood test for the detection of significant colorectal neoplasia was 29% better than that of the sensitive guaiac-based test. This may relate to the Chinese diet and requires further study. The poor specificity of the sensitive guaiac-based test, without dietary restriction, makes it less useful for colorectal cancer screening in a Chinese population.
    Alimentary Pharmacology & Therapeutics 11/2003; 18(9):941-6. DOI:10.1046/j.1365-2036.2003.01783.x
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    ABSTRACT: Population-based data on gastro-oesophageal reflux disease in Chinese are lacking. The prevalence, clinical spectrum and health care-seeking behaviour of subjects with gastro-oesophageal reflux disease were studied. Ethnic Chinese (3605) were invited to participate in a telephone survey using a validated gastro-oesophageal reflux disease questionnaire and the Hospital Anxiety and Depression Scale. A total of 2209 subjects (58% female; mean age, 40.3 years) completed the interview. The annual, monthly and weekly prevalence rates of gastro-oesophageal reflux disease were 29.8%, 8.9% and 2.5%, respectively. Gastro-oesophageal reflux disease symptoms were associated with non-cardiac chest pain [odds ratio (OR), 2.3; 95% confidence interval (95% CI), 1.7-3.1], dyspepsia (OR, 1.9; 95% CI, 1.4-2.5), globus (OR, 1.8; 95% CI, 1.2-2.7), acid feeling in the stomach (OR, 5.8; 95% CI, 4.5-7.5) and the use of non-steroidal anti-inflammatory drugs (OR, 2.3; 95% CI, 1.5-3.6), but not with dysphagia, bronchitis, asthma, hoarseness and pneumonia. Patients with gastro-oesophageal reflux disease had a significantly higher anxiety and depression score and required more days off work when compared with subjects without. The frequency of heartburn (P = 0.032), female gender (P < 0.001), degree of depression (P = 0.004) and social morbidity (P < 0.001) were independent factors associated with health care-seeking behaviour. The prevalence of gastro-oesophageal reflux disease was lower than that in Western populations, but carried a significant socio-economic burden in the studied Chinese population. The frequency of heartburn, female gender and psychosocial factors were associated with health care utilization in gastro-oesophageal reflux disease.
    Alimentary Pharmacology & Therapeutics 10/2003; 18(6):595-604. DOI:10.1046/j.1365-2036.2003.01737.x
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    ABSTRACT: To develop a validated gastro-oesophageal disease (GERD) symptom questionnaire for the Chinese population. One hundred Chinese patients with GERD and 101 healthy Chinese controls were presented with a 20-item GERD questionnaire in the Chinese language (Chinese GERDQ). Quality of life in GERD patients was assessed by SF-36. A standard dose of proton pump inhibitors for 4 weeks was prescribed to 35 patients with newly diagnosed GERD. The Chinese GERDQ was performed before, 4 weeks and 8 weeks after treatment. Concept, content, construct, discriminant validity and reliability of the questionnaire were assessed. Seven items were selected by logistic regression to account for most of the differences between controls and GERD patients with a good reproducibility and internal consistency. A cut-off score of equal or greater than 12 was determined to discriminate between controls and GERD patients with a sensitivity of 82% and a specificity of 84%. The Chinese GERDQ correlated negatively with five domains of the SF-36 and discriminated between GERD patients who reported symptomatic improvement during proton pump inhibitor treatment and symptoms deterioration upon withdrawal of proton pump inhibitor treatment. The Chinese GERDQ could be used in epidemiological studies to assess the frequency and severity of GERD in patient populations and in interventional studies of GERD.
    Alimentary Pharmacology & Therapeutics 07/2003; 17(11):1407-13. DOI:10.1046/j.1365-2036.2003.01576.x
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    ABSTRACT: The role of Helicobacter pylori and aspirin in peptic ulcer formation and recurrence remains an important clinical topic. The interaction between aspirin and H pylori in vitro is also not clear. We investigated the effect of aspirin on the growth of H pylori and on the susceptibility of H pylori to antimicrobials. Time killing studies of H pylori were performed with different concentrations of aspirin and salicylate. Growth of bacteria was assessed spectrophotometrically and by viable colony count. The effects of aspirin on the efficiency of colony formation and on metronidazole induced mutation to rifampicin resistance in H pylori were determined. Minimal inhibitory concentrations (MICs) of aspirin and metronidazole were tested by the standard agar dilution method. MICs of amoxycillin and clarithromycin were determined by the E test method. Aspirin and salicylate inhibited the growth of H pylori in a dose dependent manner and bactericidal activity was due to cell lysis. Aspirin 400 micro g/ml caused a 2 logs decrease in colony forming units/ml at 48 hours, and suppressed the normal ability of metronidazole to induce new mutations to rifampicin. The IC(90) of aspirin was 512 micro g/ml. Increased susceptibility of amoxycillin, clarithromycin, and metronidazole to H pylori was observed at 1 mM (180 micro g/ml) aspirin. Aspirin inhibited the growth of H pylori, suppressed the mutagenic effect of metronidazole, and enhanced the susceptibility of H pylori to antimicrobial agents. This mechanism is important in future drug development for effective clearing and overcoming resistance.
    Gut 05/2003; 52(4):490-5. DOI:10.1136/gut.52.4.490

Publication Stats

1k Citations
336.47 Total Impact Points

Institutions

  • 2006
    • Peking University
      Peping, Beijing, China
  • 1999–2005
    • Queen Mary Hospital
      Hong Kong, Hong Kong
  • 2003
    • Washington University in St. Louis
      San Luis, Missouri, United States
  • 2001
    • Kwong Wah Hospital
      Hong Kong, Hong Kong