Vitreoretinal surgery for macular hole after laser assisted in situ keratomileusis for the correction of myopia

AMS: To describe the characteristics and surgical outcomes of full thickness macular hole surgery after laser assisted in situ keratomileusis (LASIK) for the correction of myopia.

METHODS

13 patients (14 eyes) who developed a macular hole after bilateral LASIK for the correction of myopia participated in the study.

RESULTS

Macular hole formed 1-83 months after LASIK (mean 13 months). 11 out of 13 (84.6%) patients were female. Mean age was 45.5 years old (25-65). All eyes were myopic (range -0.50 to -19.75 dioptres (D); mean -8.4 D). Posterior vitreous detachment (PVD) was not present before and was documented after LASIK on 42.8% of eyes. Most macular hole were unilateral, stage 4 macular hole, had no yellow deposits on the retinal pigment epithelium, had no associated epiretinal membrane, were centric, and had subretinal fluid. The mean diameter of the hole was 385.3 microm (range 200--750 microm). A vitrectomy closed the macular hole on all eyes with an improvement on final best corrected visual acuity (VA) on 13 out of 14 (92.8%) patients.

CONCLUSIONS

This study shows that vitreoretinal surgery can be successful in restoring vision for most myopic eyes with a macular hole after LASIK.

Randomized double-blind comparison of ropivacaine-fentanyl and bupivacaine-fentanyl for spinal anaesthesia for urological surgery

BACKGROUND

Early studies have suggested that ropivacaine causes less motor block than bupivacaine, which might be advantageous in spinal anaesthesia for short procedures. The aim of this study was to compare plain ropivacaine 10 mg and plain bupivacaine 10 mg, both with fentanyl 15 microg, for spinal anaesthesia in urological surgery.

METHODS

This was a prospective randomized double-blind study. After written informed consent had been obtained, 34 ASA I-III patients scheduled for urological surgery were randomly assigned to receive intrathecal injection of either plain ropivacaine 10 mg with fentanyl 15 microg (ropivacaine group) or plain bupivacaine 10 mg with fentanyl 15 microg (bupivacaine group) using a combined spinal-epidural technique.

RESULTS

All patients achieved sensory block to the T10 dermatome or higher at 15 min after intrathecal injection. One patient in the ropivacaine group was excluded because of unexpectedly prolonged surgery. The primary outcome, the duration of motor block, was shorter in the ropivacaine group (median, 126 min; interquartile range, 93-162 min) compared with the bupivacaine group (median, 189 min; interquartile range, 157-234 min; difference between medians, 71 min; 95% confidence interval, 28-109 min; P = 0.003). The duration of complete motor block was also shorter in the ropivacaine group compared with the bupivacaine group. There was no difference in the onset time of motor block. The characteristics of sensory block and the haemodynamic changes were similar between the groups.

CONCLUSION

Plain ropivacaine 10 mg plus fentanyl 15 microg provided similar sensory anaesthesia, but with a shorter duration of motor block, compared with plain bupivacaine 10 mg plus fentanyl 15 microg when used for spinal anaesthesia in urological surgery.

Validated questionnaire on diagnosis and symptom severity for functional constipation in the Chinese population

BACKGROUND

Functional constipation is a common problem in clinical practice. No validated questionnaire is available in Chinese.

AIM

To develop a validated questionnaire for diagnosis and symptom assessment in functional constipation for the Chinese population.

METHODS

One hundred and eleven patients with constipation and 110 healthy controls were presented with a 24-item constipation questionnaire in the Chinese language. Quality of life in constipation patients was assessed by Short Form-36. Polyethylene glycol was prescribed, for 4 weeks, to 20 patients with newly diagnosed constipation. The questionnaire was administered before and 4 weeks after treatment. Concept, content, construct, discriminant validity and reliability of the questionnaire were assessed.

RESULTS

Six items were selected by logistic regression to account for most of the differences between controls and constipated patients with a good reproducibility and internal consistency. A cut-off score of > or =5 was determined to discriminate between controls and constipated patients with a sensitivity of 91% and a specificity of 91%. The constipation questionnaire correlated negatively with seven domains of the Short Form-36 and discriminated between constipated patients who reported symptomatic improvement during polyethylene glycol treatment.

CONCLUSIONS

The Chinese constipation questionnaire could be used in epidemiological studies to assess the frequency and severity of constipation in patient populations and in interventional studies of constipation.

Trends in the prevalence of peptic ulcer disease and Helicobacter pylori infection in family physician-referred uninvestigated dyspeptic patients in Hong Kong

BACKGROUND

Peptic ulcer disease is mainly caused by Helicobacter pylori infection and the use of non-steroidal anti-inflammatory drugs.

AIM

To investigate the trends in the prevalence of peptic ulcer disease, H. pylori infection and non-steroidal anti-inflammatory drug use in uninvestigated dyspeptic patients over recent years in Hong Kong.

METHODS

Data from consecutive patients with uninvestigated dyspeptic symptoms referred by family physicians for open access upper endoscopy during 1997 and 2003 were analysed in relation to peptic ulcer disease, H. pylori infection and non-steroidal anti-inflammatory drug use.

RESULTS

Among 2700 patients included, 405 (15%) had peptic ulcer disease and 14 (0.5%) had gastric cancer. There was a reduced trend from 1997 to 2003 in the prevalence of peptic ulcer disease (17, 20, 14, 16, 13, 14 and 14%, respectively, chi2 = 5.80, P = 0.016) (mainly because of decrease in duodenal ulcers), H. pylori infection (44, 50, 49, 44, 40, 40, 36 and 43%, respectively, chi2 = 13.55, P < 0.001) and non-steroidal anti-inflammatory drug use (13, 5, 5, 6, 3, 4, 4 and 5% respectively, chi2 = 13.61, P < 0.001). The prevalence of peptic ulcer disease, H. pylori infection and non-steroidal anti-inflammatory drug use between 2001 and 2003 were significantly lower than that between 1997 and 2000 (17% vs. 13%, OR = 0.78, 95% CI: 0.63-0.96, P = 0.020 for peptic ulcer disease; 47% vs. 39%, OR =0.72, 95% CI: 0.60-0.86, P < 0.001 for H. pylori infection; and 6% vs. 4%, OR = 0.56, 95% CI: 0.39-0.82, P = 0.002 for non-steroidal anti-inflammatory drug use). H. pylori infection was associated with both duodenal ulcer (OR = 15.87, 95% CI: 10.60-23.76, P < 0.001) and gastric ulcer (OR = 3.12, 95% CI: 2.15-4.53, P < 0.001) whereas non-steroidal anti-inflammatory drug use was only associated with gastric ulcer (OR = 2.97, 95% CI: 1.70-5.20, P < 0.001).

CONCLUSIONS

The prevalence of peptic ulcer disease, mainly duodenal ulcers, was reduced in association with a decreasing trend in the prevalence of H. pylori infection and non-steroidal anti-inflammatory drug use from 1997 to 2003.

17-year follow-up of a randomized prospective controlled trial of adjuvant intravesical doxorubicin in the treatment of superficial bladder cancer

PURPOSE

To evaluate the efficacy of adjuvant intravesical doxorubicin in superficial transitional cell carcinoma of the urinary bladder on long-term follow-up.

MATERIALS AND METHODS

Between July 1986 and November 1991, all patients harboring superficial bladder cancers (Ta or T1) with one or more of these criteria (stage>a, grade>1, size>1 cm, multiple or recurrent tumors) were randomized to receive either 50 mg doxorubicin or no adjuvant therapy. Patients with recurrences were allowed to receive doxorubicin or other intravesical agents. Recurrence, progression and survival were analyzed.

RESULTS

There were 82 patients included (64 males and 18 females). The mean age was 64 years. Forty-six patients were randomized to the doxorubicin group and 36 to the control group. Final analysis was made at median follow-up of 45, 128 and 131.5 months for recurrence, progression and survival, respectively. Recurrence free, progression free and disease specific survival did not differ significantly between groups. The 10-year Kaplan-Meier estimates for recurrence free, progression free and disease specific survival were 67%, 84% and 92%, respectively for the doxorubicin group, and were 50%, 89% and 97%, respectively for the control group. Tumor size predicted recurrence (p=0.013) and grade predicted progression (p=0.004) with multivariate analysis.

CONCLUSIONS

Adjuvant intravesical doxorubicin could not be shown to improve recurrence, progression and survival of superficial bladder cancer, compared with control on long-term follow-up. Tumor size and grade were shown to be prognostic factors for recurrence and progression, respectively.

Chest radiograph screening for tuberculosis in a Hong Kong prison

SETTING

Long-stay prisoners are not regularly screened for TB in Hong Kong.

OBJECTIVE

To evaluate tuberculosis (TB) screening in prison.

METHOD

All prisoners in a maximum security prison as of 31 October 2001 were screened by chest radiograph (CXR), except for those being followed up for TB or examined by CXR in the last 6 months.

RESULTS

A total of 814 male prisoners aged 34.6 +/- 9.6 (mean +/- SD) years were successfully screened. Of 53 cases (6.51%) with radiographic abnormalities, 10 active TB cases (8 culture-negative, 2 culture-positive) were diagnosed, giving an overall yield of 1.23% (95%CI 0.59-2.26). There was no statistical difference in age, ethnicity, place of birth or residency status between those with and those without TB (all P > 0.05). Incarceration > or = 2 years, being in current prison > or = 2 years and not having CXR in last 2 years were associated with TB in univariate analysis (all P < 0.05), but only the last remained an independent predictor in multiple logistic regression (OR 16.8, 95%CI 2.1-132.9, P = 0.008). In that group, the yield was 3.1% (95%CI 1.42-5.89). No further cases were detected in the subsequent 2 years.

CONCLUSION

CXR screening of long-stay prisoners gave a high yield in this study.

A pilot study of participation in faecal occult blood testing and screening colonoscopy after health education in Hong Kong

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.

Airway obstruction following carotid endarterectomy

Upper airway obstruction after carotid endarterectomy is a rare but potentially fatal complication of carotid endarterectomy. Upper airway obstruction is also a well recognized complication after neck surgery involving the thyroid gland and cervical spine. The airway obstruction usually develops slowly over a few hours and the onset is unpredictable. We report a patient who developed upper airway obstruction 16 hours following carotid endarterectomy. She required re-intubation in the intensive care unit (ICU). Fibreoptic assessment demonstrated severe supraglottic and glottic oedema. Tracheostomy was performed on day 2 postoperatively. Serial fibreoptic assessment of the upper airway showed gradual resolution of glottic edema and decanulation was successful on day 43.

Relation of pre-LASIK and post-LASIK retinal lesions and retinal examination for LASIK eyes

AIMS

Analysis of highly myopic eyes (mean myopia -11 D) with post-LASIK vitreoretinal complications (breaks, retinal detachment) that also had pre-LASIK vitreoretinal pathology (lattice, breaks).

METHODS

Retrospective case series.

RESULTS

67 eyes in 56 patients with pre-LASIK retinal examination developed post-LASIK vitreoretinal complications. 17 of the 67 eyes (25.4%) had pre-LASIK vitreoretinal pathology. 10 of the 17 eyes that underwent pre-LASIK prophylactic retinal treatment still developed post-LASIK lesions. They developed adjacent to pre-LASIK lesions for 15 of 17 eyes (88.2%), and outside of quadrant(s) of pre-LASIK lesions for five eyes (29.4%).

CONCLUSION

Pre-LASIK retinal examination may predict locations of certain post-LASIK retinal lesions that may develop in highly myopic eyes with pre-LASIK vitreoretinal pathology, but prophylactic treatment may not prevent all post-LASIK vitreoretinal complications.

Tuberculin response in BCG vaccinated schoolchildren and the estimation of annual risk of infection in Hong Kong

BACKGROUND

In Hong Kong there has been nearly universal neonatal BCG vaccination coverage since 1980.

METHOD

21 113 schoolchildren aged 6-9 years were skin tested with one unit of tuberculin (PPD RT-23) using the intradermal technique during a routine BCG revaccination programme. Information on sex, date of birth, date of tuberculin testing, and tuberculin reaction size at 72 hours was retrieved. The annual risk of tuberculous infection (ARTI) was estimated by three different approaches.

RESULTS

Significantly higher tuberculin positive rates were found in girls and with increasing age at all commonly used cut-off points (5, 10, and 15 mm). Using a cut-off point of > or =10 mm and the formula 1- (1 - tuberculin positive rate)(1/age), the ARTI was estimated to be 1.93% (95% CI 1.84 to 2.03) for girls and 1.41% (95% CI 1.33 to 1.50) for boys. Using the differences in the tuberculin positive rate between the 6-7 year and 8-9 year age groups, the ARTI became 1.90% (95% CI 1.09 to 2.70) and 1.84% (95% CI 1.15 to 2.54) for girls and boys, respectively. When the prevalence of infection was estimated by locating a secondary peak of the tuberculin reaction distribution curve at 15 mm and assuming a symmetrical distribution of reaction sizes among those infected around this peak, the corresponding ARTI was much lower at 0.52% (95% CI 0.46 to 0.59) and 0.43% (95% CI 0.37 to 0.49) for girls and boys, similar to that estimated indirectly from the prevalence of disease.

CONCLUSION

The ARTI as estimated by conventional methods was unexpectedly high among BCG vaccinated children and did not agree with that anticipated from the annual incidence of active disease. Further studies are needed to address the discrepancies, including the possible interaction between BCG and other environmental stimuli.

Standard treatment for Helicobacter pylori infection is suboptimal in non-ulcer dyspepsia compared with duodenal ulcer in Chinese

BACKGROUND

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.

AIM

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

A review of incisional hernia repairs: preoperative weight loss and selective use of the mesh repair

At the Shouldice Clinic pre-operative weight loss is used prior to incisional hernia repairs. Mesh repair is selectively used, based on specific hernia characteristics. A series of 236 patients were reviewed and followed up for 36 months. Data were available on 188 patients (80%). There were 15 recurrences (8%). The number of obese patients was reduced from 67 (35.6%) to 25 (13.3%) through the weight loss program. The hernia diameter, gastrointestinal complications, and surgical site infection were significantly related to recurrence but not the type of repair, obesity, location, or previous recurrences. The risk factors of incisional hernias include size, intestinal complications and infections. A selective use has a comparable result to the exclusive use of mesh repair. Weight reduction has yet to be shown to affect the rate of recurrence, and further prospective studies are required.

Onset and disappearance of reflux symptoms in a Chinese population: a 1-year follow-up study

BACKGROUND

The natural history of gastro-oesophageal reflux disease in Asian population has not been studied before.

AIM

To study the onset and disappearances of reflux symptoms over a 1-year period in the Chinese population.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Long-term pulmonary function abnormalities and survival after allogeneic marrow transplantation

We studied long-term pulmonary function testing (PFT) in a retrospective cohort of 6-month survivors of allogeneic marrow transplant (BMT) between 1980 and 1997. Of 593 patients, 73, 71 and 65% had adequate data to assess for obstruction, restriction and diffusion impairments respectively. Over 5 years, mean declines in 1-s forced expiratory volume/forced vital capacity (FEV1/FVC), total lung capacity (TLC) and diffusion were 4, 7 and 17%, respectively. TLC and diffusion tended to subsequently increase. In all, 6, 12 and 35% of patients met criteria for obstruction, restriction and impaired diffusion, respectively. Obstruction was less common in recent transplants (5 vs 15%, P=0.004), while restriction and diffusion impairment rates remained stable. There was significantly greater mortality with obstruction (HR 2.0 (1.04-3.95)), and a nonstatistically significant higher mortality rate with restriction (HR 1.6 (0.95-2.75)), but not with impaired diffusion (HR=0.99 (0.65-1.50)). cGVHD (OR 16.7 (2.2-129.8)) and busulfan (OR 2.9 (1.01-8.24)) were associated with obstruction. Marrow from nonsibling or mismatched donors (OR 4.9 (2.2-10.7)) was associated with restriction. In summary, after BMT, decreased diffusion capacity is common and benign; obstruction has decreased in frequency, is rare without cGVHD, and is associated with mortality; nonsibling and mismatched donor are risk factors for restriction.

Connectivities and synchronous firing in cortical neuronal networks

Network connectivities ((-)k) of cortical neural cultures are studied by synchronized firing and determined from measured correlations between fluorescence intensities of firing neurons. The bursting frequency (f) during synchronized firing of the networks is found to be an increasing function of (-)k. With f taken to be proportional to (-)k, a simple random model with a (-)k dependent connection probability p((-)k).has been constructed to explain our experimental findings successfully.

Socio-economic factors and tuberculosis: a district-based ecological analysis in Hong Kong

BACKGROUND

Relatively little is known about the impact of socio-economic factors on tuberculosis in a metropolitan city with high disease incidence.

METHOD

District-specific tuberculosis notification rates for 1995--1997 and 2000--2002 were indirectly sex- and age-adjusted and compared with the socio-economic characteristics in the 1996 by-census and 2001 census.

RESULTS

The differences between the 18 districts persisted after 3-year averaging and indirect standardisation. Only the percentage of population born locally, the percentage of the population widowed or divorced and the percentage of households residing in rooms or bedsits were consistently associated with the standardised notification ratios (SNR) for both periods, the first being negatively so (all P < 0.05). In a combined analysis with a general linear model for both periods, birth in China, residence <7 years, speaking other Asian languages, being married and in a single household were also significantly associated with the SNR (all P < 0.05). Using a backward conditional approach, only local birth, being married, and residing in rooms or bedsits were independent predictors of SNR (all P < 0.05). There was no significant association between SNR and socio-economic indices on education, occupation, unemployment and income.

CONCLUSION

Socio-economic factors other than simple poverty are affecting the district-specific tuberculosis rates in Hong Kong.

The role of cholecystectomy in reducing recurrent gallstone pancreatitis

BACKGROUND AND STUDY AIM

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.

PATIENTS AND METHODS

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).

RESULTS

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).

CONCLUSION

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.

Global nature of dilute-to-dense transition of granular flows in a 2D channel

The dilute-to-dense transition of granular flow of particle size d(0) is studied experimentally in a two-dimensional channel (width D) with confined exit (width d). Our results show that with fixed d and D there is a maximum inflow rate Q(c) above which the flow changes from dilute to dense and the outflow rate <Q(t)> drops abruptly from Q(c) to a dense rate Q(d). A rescaled critical rate q(c) is found to be a function of a scaling variable lambda only: q(c) approximately F(lambda), where lambda identical with d/d(0) d/D-d. This form of lambda suggests that the dilute-to-dense transition is a global property of the flow, unlike the jamming transition which depends only on d/d(0). Furthermore, the transition is found to occur when the area fraction of particles near the exit exceeds a critical value which is close to 0.65+/-0.03.

A sensitive guaiac faecal occult blood test is less useful than an immunochemical test for colorectal cancer screening in a Chinese population

BACKGROUND

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.

AIM

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Lansoprazole reduces ulcer relapse after eradication of Helicobacter pylori in nonsteroidal anti-inflammatory drug users--a randomized trial

AIM

To study whether prophylaxis with lansoprazole could prevent relapse of ulcers after eradication of Helicobacter pylori in patients with NSAID-related peptic ulcers.

METHODS

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.

RESULTS

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).

CONCLUSIONS

Lansoprazole significantly reduced the cumulative relapse of symptomatic and complicated ulcers in patients requiring NSAIDs after eradication of H. pylori.

Smoking and tuberculosis in Hong Kong

OBJECTIVE

To study the relationship between smoking and tuberculosis in Hong Kong.

METHOD

Indirect sex and age adjustment was used to compare the prevalence of ever smokers between a sample of 851 patients from the 1996 tuberculosis notification registry and the general population. The clinical characteristics of smokers and non-smokers were compared by stratified univariate analysis and multiple logistic regression.

RESULTS

Tuberculosis patients were more likely to have smoked than population controls. The respective odds ratios for ever smoking between tuberculosis patients and population controls were 2.44 and 2.08 for males and females aged 16-64 (Mantel-Haenszel weighted OR = 2.40, P < 0.001), and 2.09 and 2.83 for males and females aged > or = 65 (Mantel-Haenszel weighted odds ratio = 2.19, P < 0.001). Male sex, age > or = 65, working at onset of illness, regular alcohol use, drug abuse and absence of contact history were associated with ever smokers (all P < 0.05). Ever smokers were more likely to have cough (OR 1.69), dyspnoea (OR 1.84), upper zone involvement (OR 1.67), cavity (OR 1.76), miliary lung involvement (OR 2.77), positive sputum culture (OR 1.43), but less isolated extrathoracic involvement (OR 0.31), even after controlling for the confounding background variables (all P < 0.05).

CONCLUSION

There was a consistent association between smoking and tuberculosis. More aggressive lung involvement was also found among ever smokers.

Prevalence, clinical spectrum and health care utilization of gastro-oesophageal reflux disease in a Chinese population: a population-based study

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.