Predictors of frequent attenders of emergency department at an acute general hospital in Singapore.

OBJECTIVE: To determine factors associated with frequent emergency department (ED) attendance at an acute general hospital in Singapore. METHOD: Patients who attended the ED from 1 January to 31 December 2006 without prior attendance in the preceding 12 months (index attendance) were tracked for 12 months. Variables included in the analysis were age, gender, race, date and time of attendance, patient acuity category scale, mode of arrival, distance to ED and diagnosis based on ICD-9CM code. Frequent attenders were patients who attended the ED ≥5 times for any diagnosis within 12 months. RESULTS: A total of 82,172 patients in the study cohort accounted for a total of 117,868 visits within 12 months, of which 35,696 (30.3%) were repeat attendances. A total of 1595 patients (1.9%) were frequent attenders responsible for 8% of all repeat attendances. Stepwise logistic regression analysis found patients aged 75+ years, male, non-Chinese ethnic groups, Sunday and Monday, time of the attendance from 16:00 to midnight, distance to ED, chronic obstructive pulmonary disease, heart failure and acute respiratory infections to be significantly associated with frequent attendances. CONCLUSION: With the ageing population and their complex healthcare needs, elderly patients with chronic medical conditions are expected to make up an increasing proportion of the workload of ED in the future. A systems approach and a disease and case management approach in collaboration with primary care providers are interventions recommended to stem this.

Patient satisfaction in an observation unit: the Consumer Assessment of Health Providers and Systems Hospital Survey.

BACKGROUND: The growing demand for inpatient beds in Singapore has led Tan Tock Seng Hospital to set up an observation medicine unit where patients are monitored and discharged within a 24-h period. METHODS: Using the Consumer Assessment of Health Providers and Systems (CAHPS) Hospital Survey, this descriptive study examines the satisfaction levels of patients admitted into an observation unit, in particular the communication between patients and doctors and nurses. The anonymous surveys were either self-administered by the patients or by the research assistant or nurses. RESULTS: 271 patients completed the survey, with 96% of patients satisfied with the politeness (ie, treating them with courtesy and respect, listening carefully to them) of the medical staff. More highly educated patients were more satisfied with the communication between the doctors or nurses, compared with less educated patients (p<0.05). However, less educated patients gave a higher rating of their observation unit stay than more educated patients (p<0.05). CONCLUSION: With patient satisfaction becoming increasingly important as an indicator of the quality of care in the present healthcare environment, doctors and nurses should seek to improve their communication with their patients so as to ensure that patients are satisfied and receive quality care.

Epidemiology of sudden unexpected death syndrome among Thai migrant workers in Singapore.

A total of 235 cases of sudden unexpected death syndrome (SUDS) among apparently healthy male Thai migrant workers in Singapore were reported between 1982 and 1990. Most of the deaths occurred during sleep and 13% were not sleep-related. The median age at the time of death was 33 years and the median interval between arrival and death was 8 months. These deaths occurred singly and sporadically throughout the year. Post-mortem examination revealed few abnormal findings except for haemorrhagic congestion or oedema of the lungs. There were moderate to severe intra-alveolar haemorrhages with some evidence of myocarditis or pneumonitis. Preliminary findings of serial sections of the hearts indicate evidence of anomalies in the cardiac conduction system. Epidemiological investigations showed that a family history of similar deaths and serological evidence of current or recent infection with Pseudomonas pseudomallei were significantly associated with SUDS. Extensive biochemical and toxicological investigations were inconclusive. There was no evidence of chronic deficiency in thiamine or potassium among the healthy Thai workers living and working in the same conditions as the cases, and no significant abnormalities were detected on electrocardiographic examination. As these migrant workers experienced various psychosocial problems which could stem from maladjustment to an urban environment, separation from the family, burden of debts and long hours of work, stress could be a precipitating factor for SUDS.

Prevalence of hepatitis B virus (HBV) infection in Singapore men with sexually transmitted diseases and HIV infection: role of sexual transmission in a city state with intermediate HBV endemicity.

STUDY OBJECTIVES: To describe the prevalence of hepatitis B virus (HBV) infection in patients with sexually transmitted diseases (STD) and human immunodeficiency virus (HIV) infection, and to determine the role of sexual transmission of HBV infection in Singapore. DESIGN: A cross sectional study of all consecutive men presenting with a new episode of STD at a government outpatient clinic and all men with HIV infection on routine follow up at a government hospital. The prevalence of various HBV markers was compared with that of healthy males aged 15 years and above (controls). SETTING: Singapore, a city state of intermediate HBV endemicity. SUBJECTS: These comprised 497 STD patients, 47 HIV infected patients, and 418 controls. MAIN RESULTS: The overall seroprevalences of HBV infection in STD patients, HIV infected patients, and control subjects were 41.2%, 61.7%, and 33.3%, respectively (p < 0.001). The seroprevalences of hepatitis B surface antigen (6.2%, 8.5%, and 4.5%, respectively) were comparable in the three groups. Using stepwise logistic regression analysis, the adjusted seroprevalences of HBV infection in STD and HIV infected patients were respectively 2.4 times (95% confidence interval (CI), 1.7, 3.3) and 3.3 times (95% CI 1.7, 6.3) higher than in controls. HBV infection rates were higher among Chinese (odds ratio (OR), 1.9; 95% CI 1.6, 3.4) than non-Chinese, and among those aged 25-34 years (OR 2.4; 95% CI 1.6, 3.4), 35-44 years (OR 3.9; 95% CI 2.5, 5.9), and 45+ years (OR 6.2; 95% CI 3.8, 10.2) than in those aged 15-24 years. Sex related factors significantly associated with higher infection rates, independent of age and ethnic group, were reactive VDRL test (OR 2.4; 95% CI 1.2, 4.7), participation in anal intercourse (OR 2.3; 95% CI 1.2, 4.3), and having 10 or more lifetime sexual partners (OR 1.5; 95% CI, 1.0, 2.1). CONCLUSION: The importance of sexual transmission of HBV in an area of intermediate HBV endemicity was confirmed. Patients attending STD clinics should be routinely screened for HBV markers and those found to be seronegative should be strongly advised to be immunised against this virus.

Biological monitoring of human exposure to environmental lead in Singapore.

An epidemiological survey was conducted in 1990-91 to determine the personal and environmental factors in Singapore which may affect blood lead levels. A total of 1,408 children and adults aged from 6 months to over 50 years were interviewed and their blood samples obtained for analysis using atomic absorption spectroscopy. Overall, the geometric mean blood lead level of the population surveyed was 76.6 micrograms/l. Multivariate analyses revealed that significant variations in blood lead concentrations were related, in decreasing order of importance, to: sex, age, active and passive smoking, exposure to traffic, and exposure to recent paintwork. The consumption of alcohol and traditional medicines were found not to be significant determinants. To reduce the environmental lead problem in Singapore, unleaded petrol has been introduced and control of lead additive in paints is being considered. The national anti-smoking programme should further contribute to an overall reduction in the blood lead level of the population.

Blood cadmium levels in non-occupationally exposed adult subjects in Singapore.

Cadmium concentrations in whole blood were measured in subjects with no occupational exposure to cadmium. The study covered 128 males and 150 females from the three main ethnic groups in Singapore (namely Chinese, Malays and Indians). The geometric means (GM) of blood cadmium (CdB) levels of non-smoking males and females were 0.21 microgram/l and 0.26 microgram/l, respectively. Smokers had higher GM CdB levels than non-smokers. Significant ethnic differences were observed in both sexes, with Indian males having the highest GM CdB level of 0.48 microgram/l. Among the females, the Chinese had the highest GM CdB level: 0.33 microgram/l. Differences in dietary habits may have contributed to the observed ethnic differences in blood cadmium levels.

An evaluation of 1987 tuberculosis deaths in Singapore.

Tuberculosis was responsible for 177 deaths in 1987. This study evaluated the accuracy of tuberculosis death certification by hospital doctors and general practitioners in 111 cases where hospital case-notes were available for verification. It revealed that only 49 cases (44%) died of active tuberculosis, 12 (11%) died of late effects of tuberculosis and 41 (37%) died of causes unrelated to tuberculosis. There was no evidence of tuberculosis in 9 cases. Only 39 cases (56%) of active tuberculosis certified by hospital doctors were correct compared to 10 (24%) certified by general practitioners. Hospital doctors certified 6 out of 9 deaths which had no evidence of tuberculosis. The actual tuberculosis mortality rate was estimated to be between 1.9 and 4.9 per 100,000 instead of the officially published 6.8 per 100,000 for 1987.

A psychosocial study of high risk subjects for AIDS.

A psychosocial study of 5 high risk groups for AIDS (50 homosexuals, 50 drug addicts, 23 male to female transsexuals, 45 male patients at a sexually transmitted disease clinic, and 43 female prostitutes) and 5 matched control groups showed that the majority of the subjects were mostly single, with a secondary level of education and lived with family members. Although all had a high risk of AIDS, condom use was not prevalent. The subjects were less knowledgeable about AIDS than controls, were more anxious about getting AIDS and had a more hopeless and pessimistic outlook to life; however they appeared to be as altruistic and responsible as the controls.

Comparison of multiplex PCR and culture for detection of Legionellae in cooling tower water samples.

We compared multiplex polymerase chain reaction (PCR) and culture for detecting the presence of Legionella pneumophila and Legionella spp in cooling tower water samples. Multiplex PCR was performed after phenol extraction of DNA from the samples. The set of primers for the PCR assay involved the 5S rRNA (Legionella spp) and the mip (macrophage infectivity potentiator gene, specific for L. pneumophila) genes as target sequences for amplification. Both the sensitivity and the specificity of the PCR assay were 100% when the 5S rRNA gene was used as target sequence. Isolation of Legionellae from the samples was observed only with the PCR-positive samples. We propose that PCR be used as a screening test before attempting to culture Legionellae from cooling tower water samples.

Gestational diabetes in Singaporean women: use of the glucose challenge test as a screening test and identification of high risk factors.

In this study, 1141 antenatal women attending 9 Government polyclinics were screened between 24 and 28 weeks of gestation for gestational diabetes mellitus (GDM) using the glucose challenge test (GCT). An attempt was made to determine whether 7.2 mmol/l or 7.8 mmol/l was an effective cut-off point as an indicator for GDM. The women with GCT levels of > or = 7.2 mmol/l had an oral glucose tolerance test (OGTT) for confirmation of GDM. The results showed that 420 (36.8%) had GCT levels > or = 7.2 mmol/l, including 299 (26.2%) with GCT levels of > or = 7.8 mmol/l. Of the 190 OGTT carried out, 8 (4.2%) were confirmed to have GDM, all of whom had GCT levels of > or = 7.8 mmol/l, indicating that a GCT level of 7.8 mmol/l was the effective cut-off point. Univariate analysis showed that epidemiological features associated with a raised GCT > or = 7.8 mmol/l were, older age that is 30 years and above, Chinese ethnic group, maternal obesity (body mass index > or = 25) and history of > or = 4 pregnancies. Multivariate analysis using stepwise logistic regression, showed that factors significantly and independently associated with raised GCT levels were older age, Chinese ethnic group and maternal obesity. All antenatal women should be screened for GDM using the GCT, and those with levels of > or = 7.8 mmol/l should be subjected to the OGTT for confirmation.

A survey of sexual behaviour of Singaporeans.

In order to plan education programmes against sexually transmitted diseases (STDs) and HIV infection, a population-based survey on partner relations was conducted on 2,115 Singaporean men and women aged between 15 and 49 years. Of the 605 (60.1%) sexually experienced men and 647 (58.3%) sexually experienced women, 510 (84.3%) men and 644 (99.5%) women were married. Of the marrieds, 465 (76.9%) men and 638 (98.6%) women had their first sexual encounter with the person who was or later became their spouse. Of the sexually experienced men, 97 (16%) engaged in casual sex in the previous year, of which 76 (78.4%) were encounters with commercial sex workers. Of these encounters 55 (72.4%) were unprotected or partially protected by condoms. A history of casual sex in the previous four weeks was given by 18 men, of whom 14 (77.8%) were married. Nine (64.3%) of these married men had sex concurrently with both their wives and commercial workers. Persons at high risk were those who started sexual activity early, unmarried, sexually active men with no or low education, and persons who travelled. Of the sexually experienced respondents, 1,242 (99.2%) had heard about condoms, and 431 (34.4%) were currently using them as contraceptive devices. Attitudes towards condoms and willingness to use them to prevent STDs and HIV infection were favourable. Men were more permissive in their attitudes towards sex. The level of permissiveness in men and women was not corroborated by their reported behaviour, an indication of either under-reporting and/or a disparity between attitude and practice.

How sexually permissive are Singaporeans?

This paper presents data on two surveys done in 1989 and 1992 that indicated the attitudes of Singaporeans to sexuality. Both surveys revealed that Singaporeans have sexually conservative attitudes and those who have a lower education, are single, above the age of 40, are Malays/Muslims hold more conservative views.

Surveillance of legionellosis and Legionella bacteria in the built environment in Singapore.

During the period 1986 to 1996, a total of 258 sporadic cases of community-acquired legionellosis was reported, giving a mean annual morbidity rate of 0.9 per 100,000 population. Majority of the cases (91.5%) was serologically diagnosed by the indirect fluorescent antibody (IFA) test against Legionella pneumophila based on single sera with a titre of > or = 1:1024. The others were confirmed by a four-fold increase in IFA titre to a minimum of 1:128 (7.4%) and by culture (1.1%). Cases were reported predominantly among males, ethnic Indians, the elderly and those with concurrent medical conditions. The overall case-fatality rate was 14.7%, with the rate significantly higher among those aged > or = 45 years (21%), smokers (20.4%) and those with concurrent medical conditions (22.5%). Seroepidemiological studies among the healthy population based on an IFA titre of > or = 1:32 showed a prevalence of between 10.3% and 21.9%. Of the various occupational groups investigated, high seroprevalence rates were found in foreign construction workers (52.6%) and occupants of a building investigated for an unusual building-related illness (76.1%). Environmental surveillance of Legionella bacteria showed that 36% of cooling towers, 15% to 19% of decorative fountains and waterfalls and 2% of spa pools were positive. The majority (85%) of environmental isolates was identified as Legionella pneumophila: 54.8% of serogroup 1 and 5% of Pontiac subtype.

Epidemiological surveillance of melioidosis in Singapore.

During the period 1989 to 1996, a total of 372 cases of melioidosis, with 147 deaths, were reported, giving a mean annual incidence rate of 1.7 per 100,000 population and a case-fatality rate of 39.5%. Majority (89%) of the clinical cases were confirmed by culture of Burkholderia pseudomallei, while the others were presumptive cases based on a single blood specimen with an indirect haemaglutination (IHA) antibody titre of > or = 1:16. The highest incidence rate was reported in those aged 45 years and above (5.7 per 100,000 population), males (2.8 per 100,000 population), and Indian ethnic group (3.0 per 100,000 population). Cases were distributed throughout the island all year round. There was no correlation with rainfall. Most of the cases (77.4%) had other concurrent medical conditions, the most common being diabetes mellitus (57.5%). Factors significantly associated with a higher case-fatality rate were age (55 years and above), septicaemia, smoking history and heart or renal failure. The overall case-fatality rate has been declining from 60% in 1989 to 27% in 1996 due to a greater awareness among medical practitioners to diagnose and treat the disease early. The overall seroprevalence of IHA antibody (titre of > or = 1:16) among asymptomatic population groups was 0.2%. B. pseudomallei isolated from clinical specimens were sensitive to imipenem (100%), ceftazidime (99.1%), piperacillin (99.7%), ampicillin-clavulanate (98.5%), minocycline (97.4%), chloramphenicol (94.3%), doxycycline (94.3%) and tetracycline (93.9%). Of 395 samples of soil collected during epidemiological investigation of reported cases, 1.8% were positive for B. pseudomallei.

Stroke disease management--a framework for comprehensive stroke care.

Disease management is an approach to patient care that coordinates medical resources for the patient across the entire healthcare delivery system throughout the lifetime of the patient with the disease. Stroke is suitable for disease management as it is a well-known disease with a high prevalence, high cost, variable practice pattern, poor clinical outcome, and managed by a non-integrated healthcare system. It has measurable and actionable outcomes, with available local expertise and support of the Ministry of Health. Developing the programme requires a multidisciplinary team, baseline data on target populations and healthcare services, identification of core components, collaboration with key stakeholders, development of evidence-based clinical practice guidelines and carepaths, institution of care coordinators, use of information technology and continuous quality improvement to produce an effective plan. Core components include public education, risk factor screening and management, primary care and specialist clinics, acute stroke units, inpatient and outpatient rehabilitation facilities, and supportive community services including medical, nursing, therapy, home help and support groups for patients and carers. The family physician plays a key role. Coordination of services is best done by a network of hospital and community-based care managers, and is enhanced by a coordinating call centre. Continuous quality improvement is required, with audit of processes and outcomes, facilitated by a disease registry. Pitfalls include inappropriate exclusion of deserving patients, misuse, loss of physician and patient independence, over-estimation of benefits, and care fragmentation. Collaboration and cooperative among all parties will help ensure a successful and sustainable programme.

Epidemiological investigations into an outbreak of building-associated illness in Singapore.

In August 1991, the Ministry of the Environment was informed of the occurrence of illnesses suspected to be related to a modern, multi-story office building. Investigations revealed that 34 of the occupants on two floors of the building had non-specific ailments such as eye, throat or skin irritation which caused acute discomfort but resolved upon leaving the premises. Case-control study identified a number of factors significantly associated with the illness; viz. a personal history of allergy, asthma or sinusitis; a high level of work-related stress; and a lack of thermal comfort. One feature of the affected offices was numerous high partitions which tended to obstruct air movement. Adjustments of central temperature to compensate for complaints of "stuffiness" had resulted in wide fluctuations of temperature and relative humidity. Indoor air quality measurements also revealed high bacterial counts, a condition aggravated by the raised relative humidity and inadequate air movement. The problems gradually resolved following major modifications at the offices and air-handling units. This episode confirmed the need for further studies of building-associated illness in the tropics.

Implementing chronic disease management in the public healthcare sector in Singapore: the role of hospitals.

The public health care delivery system in Singapore faces the challenges of a rapidly ageing population, an increasing chronic disease burden, increasing healthcare cost, rising expectations and demand for better health services, and shortage of resources. It is also fragmented, resulting in duplication and lack of coordination between institutions. A disease management approach has been adopted by the National Healthcare Group (NHG) as a critical strategy to provide holistic, cost-effective, seamless and well-coordinated care across the continuum. The framework in the development of the disease management plan included identifying the diseases and defining the target population, organizing a multi-disciplinary team lead by a clinician champion, defining the core components, treatment protocols and evaluation methods, defining the goals, and measuring and managing the outcomes. As disease management and case management for chronic diseases are new approaches adopted in the healthcare delivery system, there is a lack of understanding by healthcare professionals. The leadership and participation of hospital physicians was sought in the planning, design and outcomes monitoring to ensure their 'buy-in' and the successful implementation and effectiveness of the program. The episodic diagnosis related group (DRG)-based framework of funding and subvention for healthcare, and the shortage of step-care care facilities, have been recognized by the Ministry of Health as an impediments to the implementation, and these are currently being addressed.

Stratifying healthcare costs using the Diabetes Complication Severity Index.

OBJECTIVE: We aim to determine whether healthcare costs for patients diagnosed with Type 2 Diabetes Mellitus (T2DM) are associated with the severity of diabetes complications as measured by the Diabetes Complication Severity Index (DCSI). METHODS: Retrospective cohort analysis was performed on a 2007 primary care cohort of T2DM patients. The DCSI is a 13-point scale, which comprises 7 categories of complications and their severity levels. Healthcare cost data from 2008 and 2009 were used as primary outcome. Inpatient and outpatient costs incurred for services consumed by patients within the provider network were included. Generalized linear model with log-link and gamma distribution was used to predict healthcare costs. RESULTS: Of the 59,767 T2DM patients, 2977 (5.0%) deaths occurred and 1336 (2.2%) were lost to follow up. Healthcare cost was strongly associated with increase in DCSI score. Compared to patients without complications, those with more complications (higher DCSI score) had an increased risk of higher healthcare costs. Risk ratio (RR) increased from 1.25 (95%CI: 1.19-1.32) for DCSI=1 to 1.61 (1.51-1.72) for DCSI=2; 2.10 (1.91-2.31) for DCSI=3; 2.52 (2.21-2.87) for DCSI=4 and 3.62 (3.09-4.25) for DCSI≥5. As a continuous score, a one-point increase in the DCSI was associated with a cost increase of 27% (95%CI: 1.25-1.29). CONCLUSION: The DCSI score is a useful tool for predicting direct healthcare costs. The DCSI can be used to triage high-risk patients for more focused secondary prevention interventions at primary care level, in a bid to lower overall healthcare costs.