Adverse lifestyle leads to an annual excess of 2 million deaths in China

Background

Adverse lifestyle factors have been associated with increased mortality, but data are lacking on their combined effect in developing populations, which we address in the present study.

Methods

In a death registry-based, case-control study among Hong Kong Chinese aged 30+y, proxy-reported lifestyle factors 10 y ago were collected for 21,363 cases (81% of all deaths) and 12,048 living controls. Risks associated with poor diet, inactivity, heavy alcohol intake, and smoking for all-cause and cause-specific mortality, adjusting for potential confounders, were determined, and excess deaths for the Chinese population were calculated.

Results

Adjusted odds ratios for all-cause mortality were 1.15 (95% CI 1.09, 1.23), 1.34 (1.27, 1.43), 1.36 (1.21, 1.52), and 1.58 (1.46, 1.70) for poor diet, inactivity, heavy alcohol intake and smoking, respectively. Increasing numbers of adverse lifestyle factors were associated with a dose-dependent increase in adjusted odds ratios of 1.30 (1.20, 1.40), 1.67 (1.54, 1.81), 2.32 (2.08, 2.60), and 3.85 (3.12, 4.75) for 1, 2, 3, and 4 risk factors relative to those with none. The population attributable fraction for all-cause, all-CVD and all-cancer mortality were 26.6%, 15.0%, and 32.1%, resulting in an excess of 2,017,541; 489,884; and 607,517 deaths annually, respectively. Although smoking was associated with the greatest excess loss of life (867,530), heavy drinking (680,466), and physical inactivity (678,317) were similarly important.

Conclusion

Adverse lifestyle factors contribute to one quarter of all deaths in China. Improving lifestyle practices, particularly focussing on moderating alcohol intake and increasing activity, and smoking cessation are critical to reducing the lifestyle-associated health burden.

Association between television viewing and self-esteem in children

OBJECTIVE

Few studies have examined the effect of excess television (TV) viewing on specific mental health outcomes, such as self-esteem. We explored the cross-sectional association between TV viewing hours and self-esteem in young children.

METHODS

A total of 70,210 primary 4 (US grade 4) participants of the Department of Health Student Health Service, Hong Kong, in 1998-2000 reported TV viewing hours in a standardized questionnaire. Self-esteem was assessed using the Culture-Free Self-Esteem Inventories for Children (SEI) with 4 subscales. Multivariate linear regression yielded beta coefficients (β) for SEI subscale scores by TV hours, adjusting for age, sex, body mass index, lifestyle characteristics, and highest parental education and occupational status.

RESULTS

Only 10.9% of children watched >4 hours per day, while 45.3% watched TV for 1 to ≤2 hours per day. Compared with children who watched <1 hour of TV per day, those who watched a moderate amount (1 to ≤2 hours/day) had higher (more favorable) SEI scores in the General (β = 0.09; 95% confidence interval = 0.02-0.16), Social (0.05; 0.01-0.09), and Parent-Related (0.04; 0.00-0.08) subscales but lower scores in the Academic subscale (-0.06; -0.09 to -0.02). Children who watched >2 hours of TV per day had lower SEI scores than those who watched <1 hour per day in all 4 subscales.

CONCLUSIONS

An inverted J-shaped relation was observed between TV viewing hours and self-esteem among young children. The development of self-esteem among children who report little or excessive TV viewing should be further studied.

Assessing depression in patients with chronic pain: a comparison of three rating scales

BACKGROUND

Considerable evidence has suggested depression is significantly more prevalent in patients with chronic pain. A number of studies exclusively based on Western samples have evaluated the effectiveness of depression rating scales in assessing depression in the chronic pain context. The objective of this cross-sectional study was to compare within a Chinese chronic pain sample three depression rating scales commonly used in identifying depression.

METHODS

A total of 366 Chinese patients with chronic pain attending either an orthopedic specialist clinic (n=185) or a multidisciplinary pain clinic (n=181) in Hong Kong completed a structured interview using CIS-R and two depression rating scales, the Beck Depression Inventory (BDI standard and short form) and the Center for Epidemiological Studies-Depression (CES-D). Patient scores on the BDI and CES-D were then assessed against their responses on the CIS-R to determine their effectiveness.

RESULTS

The prevalence of depression was 20.2% and 57.8% in the Orthopedics and Pain Clinic sample respectively. Results of ROC analyses showed that all the three measures performed well at predicting depression with AUC ≥ 0.89 and high sensitivity and specificity.

CONCLUSIONS

Our findings suggest that the three depression measures assessed have good predictive validity in the Chinese chronic pain context, and they could be used as screening or diagnostic measures of depression in Chinese chronic pain patients. The decision of using a specific measure and a specific cutoff score should be based on study aim and setting.

Lifestyle and socioeconomic correlates of breakfast skipping in Hong Kong primary 4 schoolchildren

OBJECTIVE

Although breakfast is associated with different benefits, breakfast skipping is increasingly common among children. This study aimed to identify lifestyle and socioeconomic correlates of breakfast skipping in Hong Kong schoolchildren.

METHODS

68,606 primary 4 participants of the Department of Health Student Health Service in 1998-2000 reported breakfast habit and other lifestyle characteristics using a standardized questionnaire. Height and weight were measured by trained SHS nurses. Socioeconomic data were reported by parents. In cross-sectional analysis, multivariate logistic regression was used to identify lifestyle and socioeconomic correlates of breakfast skipping.

RESULTS

3,598 subjects (5.2%) usually skipped breakfast. Breakfast skipping was associated with being overweight (Odds ratio=1.59, 95% CI: 1.46 to 1.73) and obese (2.06, 1.80 to 2.36), and unhealthy dietary habits including more frequent junk food (1.23, 1.14 to 1.33) but less frequent fruit/vegetable (1.23, 1.13 to 1.34) and milk (1.98, 1.80 to 2.16) intake. Breakfast skippers tended to skip lunch, do less extra-curricular physical activity, watch more television and have less educated parents.

CONCLUSIONS

Breakfast skipping was significantly related to various health-compromising lifestyle characteristics and lower parental education. Breakfast habit can be a potential lifestyle indicator. Education programmes aimed at specific target groups should encourage regular breakfast consumption.

A meta-analysis of the clinical effectiveness of school scoliosis screening

STUDY DESIGN

A meta-analysis that systematically reviewed the evaluation studies of a scoliosis screening program reported in the literature.

OBJECTIVE

To evaluate the best current evidence on the clinical effectiveness of school screening for adolescent idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA

The use of school scoliosis screening is controversial, and its clinical effectiveness has been diversely reported.

METHODS

Data sources included 3 databases, namely, PubMed, Google scholar, CINAHL database, and the references from identified reviews and studies. Studies were included if: (1) they adopted a retrospective cohort design; (2) were screened using either the forward bending test (FBT), angle of trunk rotation, or Moiré topography; (3) reported results of screening tests and radiographic assessments; (4) screened adolescents only; (5) reported the incidence of curves with a minimum Cobb angle of 10 degrees or greater; and (6) reported the number of referrals for radiography. Reviews, comments, case studies, and editorials were excluded.

RESULTS

Thirty-six studies, including 34 from the 775 initially identified studies and 2 from the references, met the selection criteria. The pooled referral rate for radiography was 5.0%, and the pooled positive predictive values for detecting curves > or =10 degrees , curves > or =20 degrees , and treatment were 28.0%, 5.6%, and 2.6%, respectively. There was substantial heterogeneity across studies. Meta-regression showed that programs using the FBT alone reported a higher referral rate (odds ratio [OR] = 2.91) and lower positive predictive values for curves > or =10 degrees (OR = 0.49) and curves > or =20 degrees (OR = 0.34) than programs using other tests. Only one small study followed students until skeletal maturity and reported the sensitivity of screening; however, the specificity was not reported. No severe publication bias was noted.

CONCLUSION

The use of the FBT alone in school scoliosis screening is insufficient. We need large, retrospective cohort studies with sufficient follow-up to properly assess the clinical effectiveness of school scoliosis screening.

Comparison of total knee arthroplasty using computer-assisted navigation versus conventional guiding systems: a prospective study

PURPOSE

To compare knee alignments in total knee arthroplasty (TKA) using computer-assisted navigation versus conventional guiding systems.

METHODS

Five men and 49 women aged 49 to 79 years underwent TKA for primary osteoarthritis of the knee with varus deformity. All valgus knees were associated with inflammatory arthritis and thus excluded. Computer-assisted navigation was used for the first 35 TKAs, whereas conventional extramedullary tibial and intramedullary femoral guiding systems were used for the next 35 TKAs. The mechanical axis, coronal tibial and femoral angles, sagittal tibial and femoral angles in the 2 groups were compared.

RESULTS

Sagittal tibial and femoral angles aligned more optimally in TKAs using computer-assisted navigation. In the respective computer-assisted navigation and conventional guiding systems, 33 (94%) and 26 (74%) of the TKAs attained a postoperative mechanical axis of <3 degrees varus/valgus.

CONCLUSION

Computer-assisted navigation gives a more consistent alignment correction and reduces outliers during implant positioning.

Posterior lumbar apophyseal ring fractures in adolescents: a report of four cases

Posterior lumbar apophyseal ring fractures are rare in adolescents. We report 4 such cases in Chinese adolescents. Two of the patients had a slipped capital femoral epiphysis; 3 of them were overweight/obese. All presented with low back pain and radicular pain. Apophyseal fractures of the upper lumbar spine usually involve the lower end plate, whereas those of the lumbar sacral spine usually involve the upper end plate. The radiological features and pathophysiology are discussed. Two of the patients were treated with laminotomy and diskectomy after conservative treatment failed. All patients had complete resolution of their neurological deficits at a mean follow-up of 2 years. Despite its benign nature, long-term follow-up is necessary to define the natural course and prognosis of the disease. A high index of suspicion is needed to diagnose these fractures in adolescents.

Alcohol and cardio-respiratory deaths in Chinese: a population-based case-control study of 32,462 older Hong Kong adults

BACKGROUND

In observational studies moderate alcohol use reduces cardio-respiratory mortality. However observational studies may be biased by many factors including residual confounding by unmeasured differences between moderate alcohol users and other groups or by changes in alcohol use with ill-health and aging. We used two different analytic strategies in an under-studied population, i.e. southern Chinese, to provide an assessment of the specific impact of moderate alcohol use on mortality from ischemic heart disease (IHD) and chronic obstructive pulmonary diseases (COPD).

METHODS

In a population-based case-control study of all adult deaths in Hong Kong Chinese in 1998, we used adjusted logistic regression to compare alcohol use in decedents aged > or = 60 years from IHD (2270) and COPD (1441) with 10,320 living and 9043 dead controls (all non-alcohol related deaths). We also examined whether the association of alcohol use with death from IHD or COPD varied with sex or smoking status.

RESULTS

Using living controls and adjusted for age, socio-economic status and lifestyle, occasional and moderate alcohol use were generally associated with lower mortality from IHD and COPD. However, using dead controls the protection of occasional and moderate alcohol use appeared to be limited to ever-smokers for IHD (odds ratio (OR) 0.58, 95% confidence interval (CI) 0.46 to 0.73 for moderate compared to never-use in ever-smokers, but OR 1.07, 95% CI 0.76 to 1.50 in never-smokers), and possibly to men for COPD. High alcohol use was associated with lower IHD mortality and possibly with lower COPD mortality.

CONCLUSION

High levels of alcohol use in an older Chinese population were associated with lower IHD mortality. Moderate alcohol use was less consistently protective against IHD mortality. Alcohol use was associated with lower COPD mortality particularly in men, either due to some yet to be clarified properties of alcohol or as the artefactual result of genetic selection into alcohol use in a Chinese population. Given the increasing use of alcohol in China with economic development, other designs and analytic strategies are needed to assess the impact of alcohol in this population, so that an evidence-based public health policy can be formulated.

Short- and medium-term outcomes of accelerated infant growth in a Hong Kong Chinese birth cohort

1. In a large, population representative,Chinese birth cohort, higher birth weight and rapid growth, particularly at 0-3 months, were associated with higher body mass index (BMI) at 7 years. 2. Boys born heavy who had grown fast had the highest BMI, but rapid growth had the largest impact in lighter-born boys. 3. Rapid growth at 0-3 months or 3-12 months was not associated with a compensatory lower risk of serious infectious morbidity. 4. The ability to grow fast may be an embodiment of good health status, rather than fast growth being causally protective.

Birth weight, infant growth, and childhood body mass index: Hong Kong's children of 1997 birth cohort

OBJECTIVE

To investigate the association between birth weight, infant growth rate, and childhood adiposity as a proxy for adult metabolic or cardiovascular risk in a Chinese population with a history of recent and rapid economic development.

DESIGN

Prospective study in a population-representative birth cohort.

SETTING

Hong Kong Chinese population.

PARTICIPANTS

Six thousand seventy-five term births (77.5% successful follow-up). Main Exposures Birth weight and growth rate (change in the weight z score) at ages 0 to 3 and 3 to 12 months. Main Outcome Measure Body mass index (BMI) (calculated as the weight in kilograms divided by the height in meters squared) z score at about age 7 years.

RESULTS

Each unit increase in the weight z score at ages 0 to 3 and 3 to 12 months increased the BMI z score by 0.52 and 0.33, respectively. Children in the highest birth weight and growth rate tertiles had the highest BMI z scores. In the lowest birth weight tertile, increases in the weight z score at ages 0 to 3 months had a larger effect on the BMI z score in boys (mean difference, 0.88; 95% confidence interval 0.69-1.07) than in girls (mean difference, 0.52; 95% confidence interval, 0.33-0.71); these differences by birth weight, growth rate at ages 0 to 3 months, and sex were significant (P = .007).

CONCLUSIONS

Faster prenatal and postnatal growth were associated with higher childhood BMI in a population with a recent history of rapid economic growth and relatively low birth weight, suggesting that maximal growth may not be optimal for metabolic risk. However, there may be a developmental trade-off between metabolic risk and other outcomes.

Does economic development contribute to sex differences in ischaemic heart disease mortality? Hong Kong as a natural experiment using a case-control study

BACKGROUND

The male excess risk of premature ischemic heart disease (IHD) mortality may be partially due to an unknown macro-environmental influence associated with economic development. We examined whether excess male risk of IHD mortality was higher with birth in an economically developed environment.

METHODS

We used multivariable logistic regression in a population-based case-control study of all adult deaths in Hong Kong Chinese in 1998 to compare sex differences in IHD mortality (1,189 deaths in men, 1,035 deaths in women and 20,842 controls) between Hong Kong residents born in economically developed Hong Kong or in contemporaneously undeveloped Guangdong province in China.

RESULTS

Younger (35-64 years) native-born Hong Kong men had a higher risk of IHD death than such women (odds ratio 2.91, 95% confidence interval 1.66 to 5.13), adjusted for age, socio-economic status and lifestyle. There was no such sex difference in Hong Kong residents who had migrated from Guangdong. There were no sex differences in pneumonia deaths by birth place.

CONCLUSION

Most of these people migrated as young adults; we speculate that environmentally mediated differences in pubertal maturation (when the male disadvantage in lipids and fat patterning emerges) may contribute to excess male premature IHD mortality in developed environments.

Clinical use of clopidogrel in acute coronary syndrome

Several therapeutic approaches have been developed to improve the outcome among patients with acute coronary syndrome (ACS). However, treatment with antithrombotic therapies such as oral glycoprotein IIb/IIIa inhibitors has been limited by the lack of efficacy and excess bleeding complications. As the publication of the landmark study Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE), the clinical benefit of early and intermediate-term use of combined antiplatelet agents--clopidogrel plus aspirin--in non-ST-segment elevation myocardial infarction (NSTEMI) patients became evident. Pretreatment and intermediate-term therapy with clopidogrel in NSTEMI ACS patients undergoing percutaneous coronary intervention (PCI) was further supported by the PCI-CURE trial. Recently, the results of two major trials Clopidogrel as Adjunctive Reperfusion Therapy-Thrombolysis in Myocardial Infarction 28, Clopidogrel and Metoprolol in Myocardial Infarction Trial established the pivotal role of clopidogrel in the other spectrum of ACS-STEMI. Coupled with the results from previous multicentre trials, these two studies provide a guide for the early and long-term use of clopidogrel in the whole spectrum of ACS. A review summarising the results of the recent clinical trials and a discussion on its implications for the clinical management of ACS is presented.

Thumb polydactyly: clinical outcome after reconstruction

PURPOSE

To evaluate clinical and cosmetic outcomes of reconstruction in thumb polydactyly and prognostic value of the Wassel classification.

METHODS

Between 1993 and 2000 inclusive, out of the patients with thumb polydactyly (involving 80 thumbs) operated on, 34 patients (36 thumbs) were available for review and underwent clinical and radiological assessment. Outcomes in terms of the Tada score and complications were recorded.

RESULTS

The mean age of patients at the time of operation was 2.8 (range, 0.6-47) years. The mean follow-up period was 5 (range, 2.4-10) years. According to the Wassel classification, 12 were type-II thumb polydactyly, 3 type-III, 11 type-IV, 6 type-V, one type-VI, and 3 type-VII. There was no perioperative mortality or wound infection. More than 88% of the patients were satisfied or very satisfied with functional and cosmetic outcomes. Postoperative complications such as scar hypertrophy, pulp atrophy, joint deformity, and instability were common but minor. Ridge nail deformity after the Bilhaut Cloquet procedure was amenable to secondary corrective procedures. All types of operated thumb polydactyly achieved similar mean Tada scores (14.7- 16.6 out of 20). The Wassel classification category, age, and surgical procedures were found to have no prognostic value with regard to the Tada score and presence of complications.

CONCLUSION

Surgery on thumb polydactyly is rewarding. The Wassel classification category can be used as a guide for treatment, although it fails to predict the occurrence of postoperative complications or Tada scores. Our patients' results can serve as guidelines of expected outcomes after reconstructive procedures in different sub-types of thumb polydactyly.

Breakage of intramedullary femoral guide rod during total knee arthroplasty: a case report

We report a rare complication during primary total knee arthroplasty. An intramedullary femoral guide rod was broken during insertion. The broken part jammed into the isthmus of the femur. An initial attempt to push the broken rod via the proximal femur by a guide wire to the distal femur was unsuccessful because the broken rod was lodged in the isthmus. Ultimately, the isthmus was opened using a flexible 9-mm end-cutting reamer, and the broken rod was pushed down to the distal femoral entry site in an antegrade fashion under image intensification. Selecting a more medial entry site on the intercondylar notch with a smaller valgus cutting angle and using a shorter guide rod can avoid such a breakage.

Diet synergies and mortality--a population-based case-control study of 32,462 Hong Kong Chinese older adults

BACKGROUND

Food and drink are not consumed in isolation and can have complimentary effects enhancing or blocking the overall uptake of nutrients. We investigated how combinations of foods, drinks, and smoking affected mortality. Method Adjusted logistic regression was used to assess the joint effect of healthy foods, less healthy foods, smoking, and alcohol use on mortality in a case-control study of all Chinese adults aged 60 or over who died in 1998; 21,494 dead cases (81% of all registered deaths) and 10,968 live controls were included.

RESULTS

There was a significant trend of increasing all-cause mortality risk with decreasing healthy food consumption (P < 0.001), and the increase in risk was significantly steeper for people with high intakes of less healthy food (P for interaction <0.001). There was a steeper risk from increasing less healthy food intake in ever-smokers and people not drinking tea regularly (P < 0.001), while the J-shaped relationship between alcohol and mortality differed in shape with level of less healthy food intake.

CONCLUSION

Intake of some dietary items may modify the effect of others. An analysis framework explicitly recognizing complementary and potentially synergistic effects of food, drinks, and smoking could enhance our understanding of dietary epidemiology.

Volar fixation of dorsally displaced distal radial fracture using locking compression plate

PURPOSE

To evaluate the functional and radiological results of treating unstable fractures of the dorsal distal radius with a volar locking plate.

METHODS

Dorsally displaced distal radial fractures in 30 patients (11 men and 19 women; mean age, 58.6 years) were fixed by volar locking compression plate and followed up for a minimum of one year.

RESULTS

At final functional assessment, 24 patients achieved excellent and 5 achieved good outcomes, with one patient exhibiting fair results. Radiological scores demonstrated 22 excellent and 8 good outcomes. No nonunion or infection occurred.

CONCLUSION

Volar locking compression plating is a safe and effective treatment for unstable fractures of the dorsal distal radius.

Depressive symptoms and smoking among Hong Kong Chinese adolescents

AIMS

To examine associations among depressive symptoms, smoking, smoking trajectories and quitting smoking in Hong Kong.

DESIGN

Prospective longitudinal design, with wave 1 at baseline (T1) and wave 2 (T2) 12 months later.

SETTING AND PARTICIPANTS

Form 1 (equivalent to 7th grade in the United States) students, mean age = 12.7 years, n = 1894.

MEASUREMENTS

Self-reported smoking status, attempts to quit and depressive symptoms.

FINDINGS

At both waves, current as well as ex-smokers had higher depressive symptoms than never smokers. T1 smoking predicted T2 depressive symptoms among those with low baseline depressive symptoms. Depressive symptoms at T1 predicted smoking at T2 among non-smokers at T1. Trajectories were defined by separating participants who were never smokers at both waves ('non-smokers'), those who smoked at both waves ('persistent smokers'), those who smoked at one time but were not smoking at either wave ('past smokers), and those who had never smoked at T1 but reported smoking a year later ('new smokers'). Persistent, past and new smokers had higher depressive symptoms at both waves than non-smokers. Smokers who reported not wanting or trying to quit and those who had been unsuccessful at quitting had higher depressive symptoms at T2 than those who successfully quit.

CONCLUSION

Our results suggest that depressive symptoms promote tobacco use in Asian adolescents by making it more likely that an adolescent will begin smoking and less likely that she or he will quit. These findings elucidate risk factors in Hong Kong for two important public health concerns for adolescents: smoking and depression.

Ethnic variations in female vulnerability after an acute coronary event

OBJECTIVE

To determine the ethnic variation of short and long term female vulnerability after an acute coronary event in a population of Chinese, Indians, and Malays.

DESIGN

Population based registry.

PATIENTS

Residents of Singapore between the ages of 20-64 years with coronary events. Case identification and classification procedures were modified from the MONICA (monitoring trends and determinants in cardiovascular disease) project.

MAIN OUTCOME MEASURES

Adjusted 28 day case fatality and long term mortality.

RESULTS

From 1991 to 1999, there were 16 320 acute coronary events, including 3497 women. Age adjusted 28 day case fatality was greater in women (51.5% v 38.6%, p < 0.001), with a larger sex difference evident among younger Malay patients. This inequality between the sexes was observed in both the pre-hospitalisation and post-admission periods. Among hospitalised patients, women were older, were less likely to have suffered from a previous Q wave or anterior wall myocardial infarction, and had lower peak creatine kinase concentrations. Case fatality was higher among women, with adjusted hazard ratios of 1.64 (95% confidence interval (CI) 1.43 to 1.88) and 1.50 (95% CI 1.37 to 1.64) for 28 day and mean four year follow up periods. There were significant interactions of sex and age with ethnic group (p = 0.017). The adjusted hazards for mortality among Chinese, Indian, and Malay women versus men were 1.30, 1.71, and 1.96, respectively. The excess mortality among women diminished with age.

CONCLUSION

In this multiethnic population, both pre-hospitalisation and post-admission case fatality rates were substantially higher among women. The sex discrepancy in long term mortality was greatest among Malays and in the younger age groups.

Transradial access for coronary angiography and angioplasty: a novel approach

Coronary angiography and angioplasty are usually performed via transfemoral access. Though this route provides an easier vascular access, it is associated with a small but potentially serious incidence of vascular complications at the puncture site that may result in significant groin haematoma, blood transfusion or require surgical repair. A useful alternative approach is through the transradial access. This route has a very low rate of vascular complications and also allows early mobilisation of patients. We performed an analysis of our experience with transradial angiography and angioplasty, demonstrating this to be a safe and effective technique suitable for most patients.

Spontaneous spinal epidural haematoma--an unusual cause of spinal cord compression

Spinal epidural haematoma is uncommon. Spontaneous spinal epidural haematoma of unknown aetiology is a rarity. This report is of two patients with spontaneous spinal epidural haematoma with different outcomes and discussion of the clinical picture and possible aetiology of this rare condition.

Salvagable free wall rupture of the left ventricle

Free wall rupture of the left ventricle remains a lethal complication of acute myocardial infarction. Nevertheless, where it presents subacutely with tamponade, salvage with a good outcome is still possible with timely pericardiocentesis preceding definitive repair using a sutureless technique.

Genotype spectrum of cervical human papillomavirus infection among sexually transmitted disease clinic patients in Hong Kong

Previous studies have suggested that a few uncommon human papillomavirus (HPV) genotypes are prevalent in Chinese cervical cancer patients. To elucidate the genotype spectrum of HPVs circulating among Hong Kong Chinese, a cross-sectional study was conducted on 553 women who attended a public sexually transmitted disease clinic. HPV DNA was detected from cervical samples using the polymerase chain reaction, followed by genotype identification based on restriction fragment length polymorphism and direct sequencing. The prevalence of HPV was 30.6% for all types combined, 14.8% for high-risk types, 10.8% for low-risk types, and 7.1% for unknown-risk types. Among the HPV-positive women, 89.9% had single type infections; whereas the other 10.1% harboured more than one HPV type. HPV11 was the most prevalent genotype, detected in 5.1% of subjects; followed by HPV16 (4.9%), HPV58 (4.3%), HPV6 (3.3%), and HPV53 and CP8304 (2.2% each). Other less common genotypes found were HPV18, 33, 39, 61, LVX160, MM4, MM7 (range: 0.7-1.6%); HPV26, 45, 54, 56, 59, and LVX100 (range: 0.4-0.5%); HPV35, 40, 52, 55, 68, MM8, and MM9 (0.2% each). This study shows that HPV58 is the second most common high-risk HPV genotype circulating among Chinese female sexually transmitted disease clinic patients in Hong Kong. This together with previous reports of the high prevalence of HPV58 among Chinese cervical cancer patients accentuate the importance of developing vaccines targeting at this otherwise uncommon genotype.

Clinical outcomes of patients with diabetes mellitus and acute myocardial infarction treated with primary angioplasty or fibrinolysis

OBJECTIVE

To compare the early and late outcomes of primary percutaneous transluminal coronary angioplasty (PTCA) with fibrinolytic treatment among diabetic patients with acute myocardial infarction (AMI).

DESIGN

Retrospective observational study with data obtained from prospective registries.

SETTING

Tertiary cardiovascular institution with 24 hour acute interventional facilities.

PATIENTS

202 consecutive diabetic patients with AMI receiving reperfusion treatment within six hours of symptom onset.

INTERVENTIONS

Fibrinolytic treatment was administered to 99 patients, and 103 patients underwent primary PTCA. Most patients undergoing PTCA received adjunctive stenting (94.2%) and glycoprotein IIb/IIIa inhibition (63.1%).

MAIN OUTCOME MEASURES

Death, non-fatal reinfarction, and target vessel revascularisation at 30 days and one year were assessed.

RESULTS

Baseline characteristics were similar in these two treatment groups except that the proportion of patients with Killip class III or IV was considerably higher in those treated with PTCA (15.5% v 6.1%, p = 0.03) and time to treatment was significantly longer (103.7 v 68.0 minutes, p < 0.001). Among those treated with PTCA, the rates for in-hospital recurrent ischaemia (5.8% v 17.2%, p = 0.011) and target vessel revascularisation at one year (19.4% v 36.4%, p = 0.007) were lower. Death or reinfarction at one year was also reduced among those treated with PTCA (17.5% v 31.3%, p = 0.02), with an adjusted relative risk of 0.29 (95% confidence interval 0.15 to 0.57) compared with fibrinolysis.

CONCLUSION

Among diabetic patients with AMI, primary PTCA was associated with reduced early and late adverse events compared with fibrinolytic treatment.

Cardiac output increases prior to development of pulmonary edema after re-expansion of spontaneous pneumothorax

Pulmonary edema following reexpansion of spontaneous pneumothorax is an uncommon complication. The underlying mechanism of this condition is unclear. We report the hemodynamic characteristics in a series of 7 male patients with spontaneous large (>50%) pneumothoraces of > or = 24 h and correlate the changes with reexpansion pulmonary edema (REPE). A pulmonary artery floatation catheter was inserted and hemodynamic data were obtained before therapeutic chest tube insertion, 1 h after chest tube insertion and the following day. Four (57%) patients developed REPE. There was a tendency for larger pneumothorax to develop REPE. Capillary wedge pressure did not change significantly 1 h after the insertion of chest tube in all our patients. Cardiac output increased significantly in patients who developed REPE compared to those who did not (+ 1.06 l/min vs -0.27 l/min; P = 0.03) 1 h after insertion of chest tube. One patient did not develop pulmonary edema despite having a large (> 80%) pneumothorax. His cardiac output did not rise 1 h after chest tube insertion. REPE is not an uncommon complication following chest tube drainage in patients with large and long-standing pneumothorax. The increase in cardiac output after chest tube insertion may be associated with subsequent development of REPE.

Gender differences in outcome after an acute myocardial infarction in Singapore

OBJECTIVES

To characterise gender and age-related differences in presentation and outcome after an acute myocardial infarction (AMI).

DESIGN

Data were derived retrospectively from the Singapore Myocardial Infarction Registry from 1988 through 1997. This database comprised all AMI cases for ages between 20 and 64 years (group A). For approximately three months a year, data were also collected for all AMI cases above the age of 64 years (group B). There were 13,048 and 4,425 cases in groups A and B respectively.

RESULTS

In age - standardised AMI rates, males outnumbered females by a factor of 4.0 and 1.7 for groups A and B respectively.The median age of presentation was higher in females for both age groups being 58 years versus 54 years for group A and 75 years versus 72 years for group B. Younger females had worse survival at 28 days and were more likely to have prior ischaemic heart disease and require resuscitation. They were also more likely to have atypical symptoms. Previous myocardial infarction was not different between the sexes in both groups. Among the older age group, there was no gender difference in prior ischaemic heart disease, 28-day survival and requirement for resuscitation.

CONCLUSION

Women who have AMI tend to be older than men. Gender differences are age-specific. Women who are 64 years and below have more atypical symptoms, prior ischaemic heart disease and worse prognosis than men after AMI. These differences are not seen in those over the age of 64.

Risk of influenza A (H5N1) infection among poultry workers, Hong Kong, 1997-1998

In 1997, outbreaks of highly pathogenic influenza A (H5N1) among poultry coincided with 18 documented human cases of H5N1 illness. Although exposure to live poultry was associated with human illness, no cases were documented among poultry workers (PWs). To evaluate the potential for avian-to-human transmission of H5N1, a cohort study was conducted among 293 Hong Kong government workers (GWs) who participated in a poultry culling operation and among 1525 PWs. Paired serum samples collected from GWs and single serum samples collected from PWs were considered to be anti-H5 antibody positive if they were positive by both microneutralization and Western blot testing. Among GWs, 3% were seropositive, and 1 seroconversion was documented. Among PWs, approximately 10% had anti-H5 antibody. More-intensive poultry exposure, such as butchering and exposure to ill poultry, was associated with having anti-H5 antibody. These findings suggest an increased risk for avian influenza infection from occupational exposure.

Coronary stenting in diabetic patients: Results from the ROSETTA registry

OBJECTIVE

Diabetes mellitus is associated with high rates of restenosis and adverse outcomes after percutaneous transluminal coronary angioplasty (PTCA). It is unclear whether coronary stenting reduces adverse events in diabetic patients after PTCA. Our purpose was to determine whether coronary stenting improves clinical event rates in diabetic patients after PTCA.

METHODS

The Routine Versus Selective Exercise Treadmill Testing After Angioplasty (ROSETTA) registry was a prospective multicenter observational study examining functional testing and adverse outcomes after successful PTCA.

RESULTS

Among the 791 patients enrolled, 180 were diabetic. A total of 90 diabetics received stents while the remaining 90 patients did not. Baseline clinical characteristics were similar between the 2 groups of patients. However, patients with stents were more likely to have complex lesions, whereas those without stents were more likely to undergo atherectomy and have greater residual coronary stenosis. At 6-month follow-up, the composite end point defined as cardiac death, unstable angina, myocardial infarction, need for repeat PTCA, or coronary artery bypass graft surgery (CABG) occurred in 25.0% of stented and 22.2% of nonstented diabetic patients (P not significant [NS]). A multivariate logistic regression analysis showed that coronary stenting was not associated with a reduced incidence of the composite end point among diabetic patients (odds ratio 0.97, 95% CI 0.46-2.05, P NS).

CONCLUSION

Coronary stenting does not improve clinical event rates in diabetic patients after PTCA.

Distally based sural neurocutaneous flaps for ankle and heel ulcers

This study assessed the use of sural neurocutaneous flaps to repair chronic ulcers in difficult-to-cover areas around the ankle and heel. Follow-up of the 14 patients included in this study ranged from 6 months to 3 years after their operation. Total flap loss occurred in two patients, both of whom had rheumatoid arthritis complicated by vasculitis. Partial flap loss occurred in three patients; all were heel ulcers. Additional skin grafting procedures were required to cover their ulcers. A lateral malleolus ulcer in a patient with rheumatoid arthritis recurred after 1 year and had to be covered with a free parascapular flap. The sural neurocutaneous flap is thus a reliable means of resurfacing ulcers in the ankle and heel region. It requires no sacrifice of major peripheral vessels and may be a useful alternative for patients with poor peripheral pulses. Its use in the presence of vasculitis, however, needs further refinement.

Mortality and smoking in Hong Kong: case-control study of all adult deaths in 1998

OBJECTIVE

To assess the mortality currently associated with smoking in Hong Kong, and, since cigarette consumption reached its peak 20 years earlier in Hong Kong than in mainland China, to predict mortality in China 20 years hence.

DESIGN

Case-control study. Past smoking habits of all Chinese adults in Hong Kong who died in 1998 (cases) were sought from those registering the death.

SETTING

All the death registries in Hong Kong.

PARTICIPANTS

27 507 dead cases (81% of all registered deaths) and 13 054 live controls aged >/=35 years.

MAIN OUTCOME MEASURES

Mortality from all causes and from specific causes.

RESULTS

In men aged 35-69 the adjusted risk ratios (and 95% confidence intervals) comparing smokers with non-smokers were 1.92 (1.70 to 2.16) for all deaths, 2.22 (1.94 to 2.55) for neoplastic deaths, 2.60 (2.10 to 3.21) for respiratory deaths (including tuberculosis, risk ratio 2.54), and 1.68 (1.43 to 1.97) for vascular deaths (each P<0.0001). In women aged 35-69 the corresponding risk ratios were 1.62 (1.40 to 1.88) for all deaths, 1.60 (1.33 to 1.93) for neoplastic deaths, 3.13 (2.21 to 4.44) for respiratory deaths, and 1.55 (1.20 to 1.99) for vascular deaths (each P<0.001). If these associations with smoking are largely or wholly causal then, among all registered deaths at ages 35-69 in 1998, tobacco caused about 33% (2534/7588) of all male deaths and 5% (169/3341) of all female deaths (hence 25% of all deaths at these ages). At older ages tobacco seemed to be the cause of 15% (3017/20 420) of all deaths.

CONCLUSIONS

Among middle aged men the proportion of deaths caused by smoking is more than twice as big in Hong Kong now (33%) as in mainland China 10 years earlier. This supports predictions of a large increase in tobacco attributable mortality in China as a whole.

Wear debris from total hip arthroplasty presenting as an intrapelvic mass

A granulomatous reaction to the small particles worn off from an implanted prosthesis is a common complication in arthroplasty. The chronic inflammatory response to the wear debris from either the polyethylene or the metal components is thought to be responsible for osteolysis, implant loosening, and finally mechanical failure. Formation of an extra-articular granulomatous tissue mass is uncommon, however. We report a case of a huge granulomatous mass that presented as an intrapelvic tumor. The prosthesis was an Anatomical Medullary Locking (AML) hip arthroplasty with cementless fixation. The polyethylene insert was manufactured by ram extrusion and sterilized with gamma irradiation in air. Fragments of the insert were among the contents in the cystic mass together with black metallic debris. There was no loosening of the prosthesis, and the acetabulum floor was preserved.

Lipodystrophia centrifugalis abdominalis infantilis: two cases from China

We report the first two Chinese patients with lipodystrophia centrifugalis abdominalis infantilis in China. The first patient was a 3-year-old girl who developed an area of hyperpigmented skin depression on the right groin which spread centrifugally to the abdomen and right lower chest. Later, another lesion developed on the neck. The second patient was a 4-year-old girl who developed multiple areas of skin depression on her bilateral groin, periumbilical region, right axilla, and chest. The lesions also extended centrifugally. Erythematous margins and lymphadenopathy were present in both cases. Inflammatory changes were found in the subcutaneous fat. The clinical pictures and histologic features supported the diagnosis of LCAI in both cases.

Use of routine functional testing after percutaneous transluminal coronary angioplasty: results from the ROSETTA Registry

BACKGROUND

The American College of Cardiology (ACC)/American Heart Association (AHA) guidelines for exercise testing suggest that only selected groups of high-risk patients should undergo routine functional testing after percutaneous transluminal coronary angioplasty (PTCA) for the detection of restenosis.

OBJECTIVES

Our purpose was (1) to document the patterns of use of post-PTCA functional testing and (2) to determine whether the choice of functional testing strategy is related to clinical characteristics of patients or whether physicians use a similar strategy for all their patients.

METHODS

The Routine Versus Selective Exercise Treadmill Testing After Angioplasty (ROSETTA) Registry is a prospective study examining the use of functional testing among 788 patients at 13 centers in 5 countries.

RESULTS

During the 6-month period after a successful PTCA, 49% of patients underwent functional testing (range among centers 10%-81%). Among patients who underwent functional testing, 39% had a clinical indication and 61% had functional testing as a routine follow-up. The first functional test was performed a median of 7 weeks after PTCA, with 13% of patients having second tests at a median of 14 weeks and 4% having additional tests at a median of 20 weeks. Univariate and multivariate analyses demonstrated that the chief determinant of the use of routine functional testing was clinical center. Aside from age (P <.0001), no baseline clinical or procedural characteristics were consistently associated with the use of routine functional testing after PTCA.

CONCLUSIONS

Physicians do not appear to be adhering to the ACC/AHA guidelines for exercise testing regarding the routine use of post-PTCA functional testing. None of the clinical characteristics identified by the ACC/AHA guidelines were associated with the routine use of post-PTCA functional testing, and the primary determinant of functional testing was the location of the center at which the patient had the PTCA.

Hierarchy of risk based on history and location of prior myocardial infarction in the thrombolytic era. GUSTO-I Investigators

BACKGROUND

Among patients receiving thrombolytic therapy for myocardial infarction, the outcome for those with a history of infarction is dramatically worse than for those with their first event. Methods And Results We performed a post hoc analysis of patients with a history of myocardial infarction enrolled in the Global Utilization of Streptokinase and TPA for Occluded arteries (GUSTO)-I trial, focusing on the impact of the location of their current and prior events on mortality rates. Within the first 24 hours, mortality rate was greatest among patients with a current infarction in a territory remote from their previous event. By 48 hours after examination, mortality rates among patients with a second anterior infarct had overtaken that among patients with a current inferior/prior anterior infarct. This hierarchy of risk persisted at both 30 days and 1 year (mortality rate at 1 year: current anterior/prior inferior 23.2% +/- 1.4%, current anterior/prior anterior 20% +/- 1.5%, current inferior/prior anterior 17% +/- 1.2%, current inferior/prior inferior 10.8% +/- 0. 9%).

CONCLUSIONS

In patients with ST-elevation myocardial infarction on a background of prior infarction, the location of current and prior events predicts a hierarchy of short- and long-term risk of death.

Emerging concepts in the management of acute myocardial infarction in patients with diabetes mellitus

Although fibrinolysis has improved survival of patients after myocardial infarction (MI), such therapy is less likely to be administered to patients with diabetes. Furthermore, these patients present later (15 min) than nondiabetics. Moreover, even with the use of early potent fibrinolytic agents, patients with diabetes continued to suffer excessive morbidity and mortality. This finding is not related to the ability of fibrinolytic agents to restore complete reperfusion or increased risk of reocclusion of the infarct-related artery. Instead, the impaired ventricular performance at the noninfarct areas and metabolic derangements during the acute phase of MI may account for the adverse outcome. The efficacy of percutaneous coronary revascularization procedures for treatment of acute MI requires further evaluation. Therapeutic approaches should consider correcting these abnormalities to afford greater survival benefit for this subset of high-risk patients.

Platelet glycoprotein IIb/IIIa receptor antagonists and their use in elderly patients

With increasing age of the general population, cardiovascular diseases are becoming a greater health burden. Coronary artery disease remains a major cause of morbidity and mortality worldwide. Among the various pathophysiological processes, platelets play a pre-eminent role. With the identification of the glycoprotein (GP) IIb/IIIa receptor as the final common pathway for platelet aggregation, potent antiplatelet agents have been developed. These GP IIb/IIIa antagonists have been shown to be effective in improving outcomes among patients undergoing percutaneous coronary interventions and for the treatment of acute coronary syndromes. By pooling the results of several large-scale trials, these benefits have been found to extend to the elderly population. Among 7860 patients undergoing percutaneous coronary intervention, the occurrence of death or myocardial infarction at 30 days was reduced from 10.0 to 5.9% (odds ratio 0.56; 95% confidence level, 0.37 to 0.83) with abciximab compared with placebo, in those >70 years of age. Importantly, this benefit was achieved without an increase in major bleeding complications. Similarly favourable trends were also observed among elderly patients treated with tirofiban or eptifibatide for acute coronary syndromes. As such, GP IIb/IIIa antagonists are effective in preventing ischaemic complications and can be safely administered to elderly patients.

Risk of influenza A (H5N1) infection among health care workers exposed to patients with influenza A (H5N1), Hong Kong

The first outbreak of avian influenza A (H5N1) occurred among humans in Hong Kong in 1997. To estimate the risk of person-to-person transmission, a retrospective cohort study was conducted to compare the prevalence of H5N1 antibody among health care workers (HCWs) exposed to H5N1 case-patients with the prevalence among nonexposed HCWs. Information on H5N1 case-patient and poultry exposures and blood samples for H5N1-specific antibody testing were collected. Eight (3.7%) of 217 exposed and 2 (0.7%) of 309 nonexposed HCWs were H5N1 seropositive (P=.01). The difference remained significant after controlling for poultry exposure (P=.01). This study presents the first epidemiologic evidence that H5N1 viruses were transmitted from patients to HCWs. Human-to-human transmission of avian influenza may increase the chances for the emergence of a novel influenza virus with pandemic potential.

Cost-efficacy modeling of functional testing with perfusion imaging to detect asymptomatic restenosis following percutaneous transluminal coronary angioplasty

The objective of this study was to perform a theoretical cost-efficacy analysis on the use of routine functional testing with perfusion imaging to identify patients with asymptomatic restenosis following percutaneous transluminal coronary angioplasty (PTCA) procedures. Approximately 50% of patients with restenosis following PTCA are asymptomatic. Routine functional testing is commonly performed at 3 to 6 months to identify these patients. The cost-efficacy associated with this strategy is unknown. Theoretical models were constructed based on assumed costs for functional testing (U.S. $1,300) and coronary angiography (U.S. $3,000). Restenosis rates were assumed to be 40%, and half of patients with restenosis were assumed to be asymptomatic. To provide a range of costs to identify a patient with asymptomatic restenosis, three scenarios were constructed based on the diagnostic test characteristics of functional testing. Sensitivity analyses were performed using a range of costs for functional testing, restenosis rates, and proportion of patients with restenosis who are asymptomatic. Depending on the diagnostic accuracy of functional testing, it costs $8,200 to $22,400 to identify an asymptomatic patient with restenosis following PTCA. The cost to identify a patient with asymptomatic restenosis varies inversely with the rates of restenosis. When restenosis rates are < 20%, the cost to identify a patient with asymptomatic restenosis exceeds $10,000. Similarly, the cost to identify a patient with asymptomatic restenosis increases when the proportion of patients with asymptomatic restenosis decreases. The cost, associated with the use of routine functional testing for the identification of asymptomatic patients with restenosis appears exorbitant. However, a formal study is warranted to determine the cost-efficacy of such a strategy. Cathet. Cardiovasc. Intervent. 48:352-356, 1999.

Antibody response in individuals infected with avian influenza A (H5N1) viruses and detection of anti-H5 antibody among household and social contacts

The first documented outbreak of human respiratory disease caused by avian influenza A (H5N1) viruses occurred in Hong Kong in 1997. The kinetics of the antibody response to the avian virus in H5N1-infected persons was similar to that of a primary response to human influenza A viruses; serum neutralizing antibody was detected, in general, >/=14 days after symptom onset. Cohort studies were conducted to assess the risk of human-to-human transmission of the virus. By use of a combination of serologic assays, 6 of 51 household contacts, 1 of 26 tour group members, and none of 47 coworkers exposed to H5N1-infected persons were positive for H5 antibody. One H5 antibody-positive household contact, with no history of poultry exposure, provided evidence that human-to-human transmission of the avian virus may have occurred through close physical contact with H5N1-infected patients. In contrast, social exposure to case patients was not associated with H5N1 infection.

Platelet glycoprotein IIb/IIIa inhibition in acute coronary syndromes

Acute coronary syndromes are a leading cause of hospitalization in industrialized countries. Current antithrombotic therapy focuses on relatively weak antiplatelet agents and heparin. The advent of inhibitors of the platelet glycoprotein IIb/IIIa receptor, the final common pathway for aggregation, provides a new therapeutic modality. Clinical trials with a total of more than 18,000 patients have clearly shown the benefits of intravenous IIb/IIIa blockade. Overall, at 30 days, 13 fewer deaths or myocardial infarctions occurred for every 1000 patients treated in these trials. This favorable outcome was extended to 6 months, resulting in 16 fewer such events per 1000 patients treated. Importantly, these benefits were not accompanied by an excessive occurrence in bleeding complications or thrombocytopenia. To further improve outcomes in this high-risk group of patients, strategies pertaining to prolonged periods of vessel passivation with oral formulations and early or delayed invasive approaches are being studied.

Diabetes mellitus: biological determinants of atherosclerosis and restenosis

Diabetes mellitus is a potent risk factor for the development of atherosclerosis. Patients with diabetes account for approximately 20% of patients presenting with acute coronary syndromes or for percutaneous coronary intervention. Furthermore, the incidence of diabetes continues to increase world-wide, such that substantial medical resources are allocated for the care of patients with diabetic cardiovascular complications. Although great strides have been made in reducing cardiovascular events in recent years, there has been little improvement in outcomes for patients with diabetes mellitus. This review will focus in the underlying patho-biology and the current status of therapeutic interventional strategies for patients with diabetes mellitus.

Case-control study of risk factors for avian influenza A (H5N1) disease, Hong Kong, 1997

In May 1997, a 3-year-old boy in Hong Kong died of a respiratory illness related to influenza A (H5N1) virus infection, the first known human case of disease from this virus. An additional 17 cases followed in November and December. A case-control study of 15 of these patients hospitalized for influenza A (H5N1) disease was conducted using controls matched by age, sex, and neighborhood to determine risk factors for disease. Exposure to live poultry (by visiting either a retail poultry stall or a market selling live poultry) in the week before illness began was significantly associated with H5N1 disease (64% of cases vs. 29% of controls, odds ratio, 4.5, P=.045). By contrast, travel, eating or preparing poultry products, recent exposure to persons with respiratory illness, including persons with known influenza A (H5N1) infection, were not associated with H5N1 disease.

Trends in mortality, incidence, hospitalisation, cardiac procedures and outcomes of care for coronary heart disease in Singapore, 1991-1996

In this study, we used Singapore population-based data from 1991 to 1996 to examine recent trends in mortality, incidence and hospitalisation for acute myocardial infarction (AMI), and explored the roles of primary prevention and medical care interventions in explaining these trends. We examined trends in medical interventions, namely coronary angiography (catheterisation), coronary artery bypass graft (CABG), and percutaneous transluminal coronary angioplasty (PTCA), length of stay, and payment methods, and explored the roles of technological, healthcare financing and delivery, and regulatory factors in influencing the diffusion and outcomes of these medical interventions. During the period 1991 to 1996, there were parallel declines in resident population rates of mortality, incidence and hospitalisation for AMI. The rates of angiograms, CABG and PTCA among residents also increased greatly, with the greatest increase among elderly aged 60 years and above. The rates of invasive cardiac procedures for AMI were all lower in females than in males. The population case-fatality rate of AMI declined slightly only for persons below 40 years of age. The case-fatality rate was higher in females than in males. The number of hospitalisations and cardiac procedures all rose sharply, and was phenomenal for PTCA (247%). The increase in volume of resource use was starkly greater in private hospitals than in restructured hospitals. The ratios of PTCA to CABG from 1991 to 1996 for private and restructured hospitals showed a greater rate of technology substitution in restructured hospitals than in private hospitals. The average length of stay (LOS, 6.7 days) was fairly constant in restructured hospitals. For private hospitals, LOS declined from 7.6 days in 1991 to 5.6 in 1996. LOS varied little among individual restructured hospitals, but widely among private hospitals. The most common method of payment for AMI hospitalisation was Medisave alone (50%), but for CABG surgery, the proportion of payment made through this method was only 12%. Out-of-pocket payments, Medisave, Medishield and private insurance have increased steadily. These data indirectly suggest that primary prevention and medical care interventions might have begun to succeed in reducing the rates of coronary heart disease in Singapore. The sharp increases in cardiac procedures may be explained by changing supply and demand factors for care of AMI and chronic ischaemic heart disease, including consumer preference for cardiac procedures, overuse of medical intervention, and technological change. More studies are needed to test these hypotheses.