Predictors of disease severity in SARS-CoV-2 omicron variant XBB sublineages and variants of interest

The Omicron variant has been reported to present with milder disease compared with Delta, although this may be due to immunity from vaccination and prior exposure. Predictors of severity with recent strains have not been well characterized. We retrospectively examined consecutive cases of moderate-to-severe COVID-19 (defined as requiring supplemental oxygenation, intensive care or mortality) admitted to seven tertiary hospitals across Singapore in April 2023. Whole genome sequencing was performed on each isolate to determine the sublineage, while baseline clinical, laboratory data and outcomes were tabulated. We reviewed 182 patients with moderate-to-severe illness and 466 controls hospitalized at the same time. Advanced age and presence of chronic kidney disease predicted adverse outcome. Previously reported markers such as radiographic evidence of pneumonia, elevated C-reactive protein and serum creatinine levels at presentation also correlated with adverse outcomes. There were no observable differences in outcomes with any specific Omicron XBB sublineage. We did not find any specific Omicron XBB sublineage that was associated with worse outcomes. Larger multinational studies would be important to track the clinical evolution of the virus in its current endemic state.

Coronavirus disease and home recovery: a Singapore perspective

Objective

At the beginning of the coronavirus disease (COVID-19) pandemic in Singapore, the strategy initially involved aggressive ring-fencing of infections, before pivoting towards managing recurrent local interspersed outbreaks of COVID-19. A key feature of Singapore's efforts to preserve health-care capacity was the implementation of the nationwide Home Recovery Programme (HRP), whereby patients were allowed to recover at home as long as they met certain criteria. The programme was centrally coordinated by Singapore's Ministry of Health and was supported by telemedicine providers, primary care physicians and government agencies. This report aims to highlight Singapore's experience in coordinating and implementing the HRP, the challenges faced and the outcomes.

Methods

Published and internal data from the Ministry of Health in Singapore, along with policy documents, were reviewed together with a brief literature review of similar programmes conducted globally.

Results

Implementation of the HRP led to the majority of patients (98%) recovering from COVID-19 in the outpatient setting, with similar mortality rates to inpatient settings. Hospitalization rates for COVID-19 cases were reduced as compared to previously, alleviating strain on the health-care system.

Discussion

The HRP was largely successful at preventing health-care capacities from being overwhelmed, while keeping fatalities to a minimum. Nonetheless, the risks of emergent variants of concern remain present, and heightened vigilance and potential modification of existing protocols based on fluctuations in virulence and infectivity are still needed.

National HIV programme testing recommendations

In recognition of the morbidity and mortality associated with human immunodeficiency virus (HIV), the Joint United Nations Programme on HIV/acquired immunodeficiency syndrome (AIDS) (UNAIDS) aims to end the epidemic by setting and striving to achieve the ambitious 95-95-95 targets. However, Singapore is still not performing well in the first UNAIDS target. The National HIV Programme (NHIVP) developed this set of recommendations based on an adaptation of major international guidelines from the World Health Organization and the US Centers for Disease Control and Prevention. The goals of this recommendation are: (1) to increase the uptake of HIV testing; (2) to allow earlier detection and identification of individuals with unrecognised HIV infection; (3) to facilitate linkage to clinical services; and (4) reduce further transmission of HIV infection in Singapore.

Real-world effectiveness of sotrovimab and remdesivir for early treatment of high-risk hospitalized COVID-19 patients: A propensity score adjusted retrospective cohort study

Early treatment of high-risk COVID-19 patients may prevent disease progression. However, there are limited data to support treatment of hospitalized or fully vaccinated patients with mild-to-moderate disease. In this retrospective cohort study, we studied the effect of early use of sotrovimab and remdesivir in high-risk hospitalized COVID-19 patients. We included PCR-confirmed COVID-19 patients admitted to the National Centre for Infectious Diseases who presented within the first 5 days of illness, and who were not requiring oxygen or ICU care at presentation. Sotrovimab- and remdesivir-treated groups were compared with control (no early treatment). A multiple propensity-score adjusted multivariable regression analysis was conducted with a composite primary endpoint of in-hospital deterioration (oxygen requirement, ICU admission, or mortality). Of 1118 patients, 841 were in the control group, 106 in the sotrovimab group and 169 in the remdesivir group. The median age was 63 years (IQR 46-74 years) and 505 (45.2%) were female. In unvaccinated patients, both remdesivir and sotrovimab treatment were protective (adjusted odds ratio [aOR] 0.19, 95% CI 0.064-0.60 and 0.18 [95% CI 0.066-0.47]), respectively. Contrarily, among the vaccinated patients there was no significant treatment effect with early remdesivir treatment (aOR 2.51, 95% CI 0.83-7.57, p = 0.10). Remdesivir and sotrovimab treatment, given early in the disease course to unvaccinated high-risk patients, was effective in reducing the risk of in-hospital deterioration and severe disease. This effect was not seen in fully vaccinated patients, which may be due to a small sample size or residual confounding.

Prevalence of measles antibodies among migrant workers in Singapore: a serological study to identify susceptible population subgroups

Background

In 2019, two clusters of measles cases were reported in migrant worker dormitories in Singapore. We conducted a seroprevalence study to measure the level of susceptibility to measles among migrant workers in Singapore.

Methods

Our study involved residual sera of migrant workers from seven Asian countries (Bangladesh, China, India, Indonesia, Malaysia, Myanmar and the Philippines) who had participated in a survey between 2016 and 2019. Immunoglobulin G (IgG) antibody levels were first measured using a commercial enzyme-linked immunosorbent assay (ELISA) test kit. Those with equivocal or negative IgG results were further evaluated using plaque reduction neutralization test (PRNT).

Results

A total of 2234 migrant workers aged 20–49 years were included in the study. The overall prevalence of measles IgG antibodies among migrant workers from the seven Asian countries was 90.5% (95% confidence interval 89.2–91.6%). The country-specific seroprevalence ranged from 80.3 to 94.0%. The seroprevalence was significantly higher among migrant workers born in 1965–1989 than those born in 1990–1999 (95.3% vs. 86.6%, p < 0.0005), whereas there was no significant difference by gender (90.8% in men vs. 89.9% in women, p = 0.508). 195 out of 213 samples with equivocal or negative ELISA results were tested positive using PRNT.

Conclusion

The IgG seroprevalence in migrant workers was below the herd immunity threshold of 95% for measles. Sporadic outbreaks may occur in susceptible individuals due to high transmissibility of measles virus. Seroprevalence surveys can help identify susceptible subgroups for vaccination.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07066-2.

Seroprevalence of IgG antibodies against diphtheria antitoxin among migrant workers in Singapore, 2016-2019

Background

Since the last local case of diphtheria in 1992, there had not been any case in Singapore until an autochthonous case was reported in 2017. This fatal diphtheria case of a migrant worker raised concerns about the potential re-emergence of locally transmitted toxigenic diphtheria in Singapore. We conducted a seroprevalence study to assess the immunity levels to diphtheria among migrant workers in Singapore.

Methods

Residual sera from migrant workers who hailed from Bangladesh, China, India, Indonesia, Malaysia, Myanmar and the Philippines were tested for anti-diphtheria toxoid immunoglobulin G (IgG) antibodies. These migrant workers previously participated in a survey between 2016 and 2019 and had provided blood samples as part of the survey procedure.

Results

A total of 2176 migrant workers were included in the study. Their overall mean age was 27.1 years (standard deviation 5.0), range was 20–43 years. The proportion having at least basic protection against diphtheria (antitoxin titres ≥ 0.01 IU/ml) ranged from 77.9% (95% confidence interval [CI] 72.8 – 82.3%) among migrant workers from Bangladesh to 96.7% (95% CI 92.5 – 98.6%) in those hailing from Malaysia. The proportion showing full protection (antitoxin titres ≥ 0.10 IU/ml) ranged from 10.1% (95% CI 6.5 – 15.4%) in Chinese workers to 23.0% (95% CI 17.1 – 30.3%) in Malaysian workers. There were no significant differences in the proportion with at least basic protection across birth cohorts, except for those from Bangladesh where the seroprevalence was significantly lower in younger migrant workers born after 1989.

Conclusions

The proportions having at least basic protection against diphtheria in migrant workers from five out of seven Asian countries (India, Indonesia, Malaysia, Myanmar and the Philippines) were higher than 85%, the threshold for diphtheria herd immunity. Seroprevalence surveys should be conducted periodically to assess the level of immunity against diphtheria and other vaccine preventable diseases in migrant worker population, so that appropriate interventions such as booster vaccination can be implemented proactively to prevent sporadic outbreaks.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-12528-y.

Comparison of mental-physical comorbidity, risk of death and mortality among patients with mental disorders - A retrospective cohort study

AIM

To compare the risk of death, the prevalence of comorbid chronic physical illness and mortality among an Asian population of patients with mental disorders.

METHODS

This was a retrospective data analysing of medical records of patients with schizophrenia, depression, anxiety, bipolar disorder, alcohol use disorder (AUD) or substance use disorder and the comorbid chronic physical illnesses. The hazard risk of death was calculated with Cox regression and compared between patients with and without comorbid chronic physical illness(es). Odds ratios of specific comorbid chronic physical illness were calculated with logistic regression and mean crude death rate was calculated for patients with different mental disorders.

RESULTS

A total of 56,447 patients with mental disorders were included in the analysis. Compared to patients without comorbid physical illness, patients with mental-physical comorbidity were associated with a higher risk of death [2.36 (2.22-2.52); hazard ratio (95% CI)] and less estimated survival days [2157 (2142-2172) vs 2508 (2504-2513)]. Compared to other mental disorders, those with AUD had the highest prevalence of two or more comorbid chronic physical illnesses and associated with the highest odds of comorbid hypertension, diabetes mellitus, stroke, nephritis, chronic kidney disease, and cancer. The highest one-year crude death rate was similarly observed in patients with AUD.

CONCLUSIONS

Mental-physical comorbidity was associated with a higher risk of death compared to patients with mental disorders only. The highest prevalence of mental-physical comorbidity and mortality were observed in patients with AUD. More attention and resources may be needed to tackle the burden of AUD.

Epidemiological factors associated with the absence of previous HIV testing among HIV-positive persons in Singapore, 2012-2017

OBJECTIVE

To assess the temporal trend and identify risk factors associated with the absence of previous HIV testing prior to their diagnosis among HIV-positive persons in Singapore.

STUDY DESIGN

Cross-sectional.

SETTING AND PARTICIPANTS

We analysed data of HIV-positive persons infected via sexual transmission, who were notified to the National HIV Registry in 2012-2017.

OUTCOMES

Epidemiological factors associated with the absence of HIV testing prior to diagnosis were determined separately for two groups of HIV-positive persons: early and late stages of HIV infection at diagnosis.

RESULTS

2188 HIV-positive persons with information on HIV testing history and CD4 cell count were included in the study. The median age at HIV diagnosis was 40 years (IQR 30-51). Nearly half (45.1%) had never been tested for HIV prior to their diagnosis. The most common reason cited for no previous HIV testing was 'not necessary to test' (73.7%). The proportion diagnosed at late-stage HIV infection was significantly higher among HIV-positive persons who had never been tested for HIV (63.9%) compared with those who had undergone previous HIV tests (29.0%). Common risk factors associated with no previous HIV testing in multivariable logistic regression analysis stratified by stage of HIV infection were: older age at HIV diagnosis, lower educational level, detection via medical care and HIV infection via heterosexual transmission. In the stratified analysis for persons diagnosed at early-stage of HIV infection, in addition to the four risk factors, women and those of Malay ethnicity were also less likely to have previous HIV testing prior to their diagnosis.

CONCLUSION

Targeted prevention efforts and strategies are needed to raise the level of awareness of HIV/AIDS and to encourage early and regular screening among the at-risk groups by making HIV testing more accessible.

Short-term mortality from HIV-infected persons diagnosed from 2012 to 2016: Impact of late diagnosis of HIV infection

We investigated the temporal trends of short-term mortality (death within 1 year of diagnosis) and cause-specific deaths in human immunodeficiency virus (HIV)-infected persons by stage of HIV infection at diagnosis. We also assessed the impact of late diagnosis (LD) on short-term mortality.Epidemiological records of HIV-infected Singapore residents from the National HIV Registry were linked to death records from the Registry of Births and Deaths for observational analyses. Newly-diagnosed HIV cases with available cluster of differentiation 4 count at time of diagnosis in a 5-year period from 2012 to 2016 were included in the study. Hazard ratios (HRs) and 95% confidence interval (CI) of LD for all deaths excluding suicides and self-inflicted or accidental injuries, and HIV/ acquired immunodeficiency syndrome (AIDS)-related deaths occurring within 1 year post-diagnosis were calculated using Cox proportional hazards regression models with adjustment for age at HIV/AIDS diagnosis. Population attributable risk proportions (PARPs) were then calculated using the adjusted HRs.Of the 1990 newly-diagnosed HIV cases included in the study, 7.2% had died by end of 2017, giving an overall mortality rate of 2.16 per 100 person-years (PY) (95% CI 1.82-2.54). The mortality rate was 3.81 per 100 PY (95% CI 3.15-4.56) in HIV cases with LD, compared with 0.71 (95% CI 0.46-1.05) in non-LD (nLD) cases. Short-term mortality was significantly higher in LD (9.1%) than nLD cases (1.1%). Of the 143 deaths reported between 2012 and 2017, 58.0% were HIV/AIDS-related (nLD 28.0% vs LD 64.4%). HIV/AIDS-related causes represented 70.4% of all deaths which occurred during the first year of diagnosis (nLD 36.4% vs LD 74.7%). The PARP of short-term mortality due to LD was 77.8% for all deaths by natural causes, and 87.8% for HIV/AIDS-related deaths.The mortality rate of HIV-infected persons with LD was higher than nLD, especially within 1 year of diagnosis, and HIV/AIDS-related causes constituted majority of these deaths. To reduce short-term mortality, persons at high risk of late-stage HIV infection should be targeted in outreach efforts to promote health screening and remove barriers to HIV testing and treatment.

Epidemiological factors associated with recent HIV infection among newly-diagnosed cases in Singapore, 2013-2017

Background

Early diagnosis is crucial in securing optimal outcomes in the HIV care cascade. Recent HIV infection (RHI) serves as an indicator of early detection in the course of HIV infection. Surveillance of RHI is important in uncovering at-risk groups in which HIV transmission is ongoing. The study objectives are to estimate the proportion of RHI among persons newly-diagnosed in 2013–2017, and to elucidate epidemiological factors associated with RHI in Singapore.

Methods

As part of the National HIV Molecular Surveillance Programme, residual plasma samples of treatment-naïve HIV-1 positive individuals were tested using the biotinylated peptide-capture enzyme immunoassay with a cutoff of normalized optical density ≤ 0.8 for evidence of RHI. A recent infection testing algorithm was applied for the classification of RHI. We identified risk factors associated with RHI using logistic regression analyses.

Results

A total of 701 newly-diagnosed HIV-infected persons were included in the study. The median age at HIV diagnosis was 38 years (interquartile range, 28–51). The majority were men (94.2%), and sexual route was the predominant mode of HIV transmission (98.3%). Overall, 133/701 (19.0, 95% confidence interval [CI] 16.2–22.0%) were classified as RHI. The proportions of RHI in 2015 (31.1%) and 2017 (31.0%) were significantly higher than in 2014 (11.2%). A significantly higher proportion of men having sex with men (23.4, 95% CI 19.6–27.6%) had RHI compared with heterosexual men (11.1, 95% CI 7.6–15.9%). Independent factors associated with RHI were: age 15–24 years (adjusted odds ratio [aOR] 4.18, 95% CI 1.69–10.31) compared with ≥55 years; HIV diagnosis in 2015 (aOR 2.36, 95% CI 1.25–4.46) and 2017 (aOR 2.52, 95% CI 1.32–4.80) compared with 2013–2014; detection via voluntary testing (aOR 1.91, 95% CI 1.07–3.43) compared with medical care; and self-reported history of HIV test(s) prior to diagnosis (aOR 1.72, 95% CI 1.06–2.81).

Conclusion

Although there appears to be an increasing trend towards early diagnosis, persons with RHI remain a minority in Singapore. The strong associations observed between modifiable behaviors (voluntary testing and HIV testing history) and RHI highlight the importance of increasing the accessibility to HIV testing for at-risk groups.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10478-5.

Coronavirus Disease 2019 (COVID-19): The Singapore Experience. A Review of the First Eight Months

As of 27 October 2020, there have been 57,980 confirmed cases of COVID-19 in Singapore, with 28 fatalities. To summarise the Singapore experience in managing and containing COVID-19 based on available published data and from relevant sources, a review of literature using research databases such as PubMed and OVID Medline, along with non-peer-reviewed articles and other sources, was conducted with the search terms ‘COVID-19’ and ‘Singapore’. Research conducted in Singapore has provided insight into the clinical manifestations and period of infectivity of COVID-19, demonstrated evidence of pre-symptomatic transmission, linked infection clusters using serological tools, and highlighted aspects of hospital-based environmental contamination. It has also provided guidance for diagnostic testing and has described immune and virologic correlates with disease severity. Evidence of effectiveness of containment measures such as early border control, rigorous contact training, and calibrated social distancing measures have also been demonstrated. Singapore’s multipronged strategy has been largely successful at containing COVID-19 and minimising fatalities, but the risk of re-emergence is high. Keywords: Epidemiology, management, prevention, transmission

Coronavirus Disease 2019 (COVID-19): The Singapore Experience. A Review of the First Eight Months

As of 27 October 2020, there have been 57,980 confirmed cases of COVID-19 in Singapore, with 28 fatalities. To summarise the Singapore experience in managing and containing COVID-19 based on available published data and from relevant sources, a review of literature using research databases such as PubMed and OVID Medline, along with non-peer-reviewed articles and other sources, was conducted with the search terms 'COVID-19' and 'Singapore'. Research conducted in Singapore has provided insight into the clinical manifestations and period of infectivity of COVID-19, demonstrated evidence of pre-symptomatic transmission, linked infection clusters using serological tools, and highlighted aspects of hospital-based environmental contamination. It has also provided guidance for diagnostic testing and has described immune and virologic correlates with disease severity. Evidence of effectiveness of containment measures such as early border control, rigorous contact training, and calibrated social distancing measures have also been demonstrated. Singapore's multipronged strategy has been largely successful at containing COVID-19 and minimising fatalities, but the risk of re-emergence is high.

Healthcare workers in Singapore infected with COVID-19: 23 January-17 April 2020

Objective

To describe the characteristics of healthcare workers (HCWs) infected with COVID‐19 and to examine their sources of exposure.

Methods

A descriptive cross‐sectional study using data extracted from the centralized disease notification system comprising individuals confirmed with COVID‐19 in Singapore between 23 January and 17 April 2020. Occupation of HCWs was categorized into six categories. Their job nature was classified into “frontline” or “back‐end” based on the frequency of direct patient contact, and source of exposure was classified as family/household, social interaction or workplace. Chi‐square and median tests were used to identify differences between categorical groups and sample medians, respectively.

Results

A total of 88 (1.7%) HCWs were identified from 5,050 cases. Their median age was 35 years. Chinese and Indians constituted 42.0% and 31.8%, respectively, and 43.2% were foreigners. The majority (63.6%) was serving at frontlines handling patient‐facing duties, 15.9% were doctors, 11.4% were nurses and 44.3% were ancillary staff. About 81.8% acquired the infection locally, of which 40.3% did not have a clearly identifiable source of exposure. Exposure from the family/household was most common (27.8%), followed by workplace (16.7%) and social interaction (15.3%). All HCWs were discharged well with no mortality; three (3.4%) were ever admitted to intensive care unit and required increased care.

Conclusion

Healthcare workers accounted for a small proportion of COVID‐19 cases in Singapore with favourable outcomes. The possibility of transmission resulting from family/household exposure and social interactions highlights the need to maintain strict vigilance and precautionary measures at all times beyond the workplace.

Impact of medication nonadherence on stroke recurrence and mortality in patients after first-ever ischemic stroke: Insights from registry data in Singapore

PURPOSE

This retrospective cohort study aims to examine adherence to secondary stroke preventive medications and their association with risk of stroke recurrence and mortality in patients after first-ever ischemic stroke.

METHODS

Using data from the National Healthcare Group and Singapore Stroke Registry, patients with first-ever ischemic stroke between 2010 and 2014 were included, and categorized based on antithrombotic or statin adherence using the proportion of days covered: high (≥75%), intermediate (50%-74%), low (25%-49%), and very low (<25%). The primary outcome was first recurrent ischemic stroke within a year after hospital discharge, while the secondary composite outcomes were (a) stroke recurrence and all-cause mortality and (b) stroke recurrence and cardiovascular mortality. The Cox proportional hazard model was used to examine the association between medication adherence and outcomes. Adjusted hazard ratios (aHRs) and the corresponding 95% confidence intervals (CIs) were reported.

RESULTS

Among ischemic stroke patients prescribed with antithrombotics (n = 1139) or statins (n = 1160) at hospital discharge, about one-third were highly adherent to their medications. Patients with lower medication adherence tended to be younger, were admitted to private ward classes, and were without hypertension. Compared with the patients with high medication adherence, the risk of stroke recurrence was higher in patients with very low antithrombotic (aHR = 4.65; 95% CI: 1.45-14.89) or statin (aHR = 3.44; 95% CI: 0.93-12.74) adherence. Similar findings were observed for the secondary outcomes.

CONCLUSIONS

Poor adherence to antithrombotic and statin treatment increases the risk of recurrent stroke and mortality in patients after first-ever ischemic stroke. Further measures are needed to improve medication adherence among stroke survivors.

Predictive factors of developing type 2 diabetes mellitus, Acute Myocardial Infarction and stroke in a cohort with Impaired Fasting Glucose in Singapore

AIMS

This study describes the incidence and predictive factors for development of Type II Diabetes Mellitus (T2DM), Acute Myocardial Infarction (AMI) and stroke, among subjects with IFG over a five-year period.

METHODS

This is a retrospective cohort study of subjects with newly diagnosed IFG from the Singapore National Healthcare Group hospitals and primary care clinics from 1 January 2008 to 31 December 2010. Clinical data were collected over a five-year period from the date of diagnosis. Outcomes of interest were T2DM, AMI and stroke based on first occurrence of the ICD-9 diagnoses from the chronic disease registry. Demographic characteristics, laboratory tests, anthropometric measurements and medical history were adjusted for in the multivariate logistic regression.

RESULTS

Out of 2295 eligible subjects, 552(24.1%) developed at least one of the outcomes. 492(21.4%) developed T2DM, 20(0.9%) developed AMI and 62(2.7%) developed stroke. Predictive factors for development of any of the three outcomes included age 40-49 [Adjusted OR=2.25; 95% CI 1.44-3.51], blood pressure of 140/90mmHg and above [Adjusted OR=1.62, 95% CI 1.26-2.10] and BMI of 27.5kg/m² or more [Adjusted OR=2.35; 95% CI 1.61-3.41]. Females were more likely to develop T2DM [Adjusted OR=1.43; 95% CI 1.10-1.85] but less likely to develop AMI and/or stroke compared to males [Adjusted OR=0.43; 95% CI 0.24-0.76].

CONCLUSIONS

Development of T2DM/AMI/stroke within the first five years of IFG is significantly high for subjects age 40-49 and those with high BMI. Frequency of cardiovascular risk screening, which is currently once every three years, could be increased.

Projection of prediabetes and diabetes population size in Singapore using a dynamic Markov model

BACKGROUND

The aim of the present study was to forecast the prevalence and number of adult Singapore residents with prediabetes and diabetes in 2035.

METHODS

A dynamic Markov model with nine mutually exclusive states was developed based on the clinical course of diabetes using time-dependent rates and probabilities. A 1-year cycle over a 25-year time horizon from 2010 to 2035 was used in the model. With publicly available data and a chronic disease register, the model forecast annual disease burden by simulating transition of cohorts across different health states using prevalence rates, incidence rates, mortality rates, disease transition, disease detection, and complication rates. An aging index was used in the model in anticipation of population aging to minimize risks of underestimating disease burden.

RESULTS

From 2010 to 2035, the number of Singapore residents with prediabetes and diabetes is projected to more than double, from 434 685 to 903 596 and from 373 104 to 823 802, respectively. The prevalence of prediabetes and diabetes will rise steadily from 15.5 % to 24.9 % and from 13.3 % to 22.7 %, respectively. By 2035, a further estimate of 733 174 and 100 250 patients with prediabetes and uncomplicated diabetes, respectively, will remain undiagnosed. The prevalence of detected and undetected complications is forecast to rise from 60.0 % in 2010 to 70.2 % by 2035.

CONCLUSION

By 2035, the prevalence of prediabetes and diabetes among Singapore residents aged 21+ years is expected to be one in four and one in five, respectively. There is an impetus to adopt more aggressive interventions to contain disease progression.

Beliefs, perceptions and psychosocial impact of acne amongst Singaporean students in tertiary institutions

BACKGROUND

Acne vulgaris is a common skin condition which can have a negative impact on a patient's quality of life.

PATIENTS AND METHODS

A survey was distributed among students at tertiary institutions. Data was collected on participants' own rating of acne grade and how acne affected their social life. A clinician on-site graded the participants' acne.

RESULTS

Of the 429 students who participated in the survey, 59.8 % felt embarrassed or self-conscious because of their acne. There was a low but statistically significant correlation (Spearman's Correlation Coefficient = 0.471, p < 0.001) between participants' and clinicians' grading of acne.

CONCLUSIONS

Acne vulgaris causes a considerable amount of psychosocial stress. There are unfounded beliefs surrounding acne and unawareness of treatment options available.

Ethnic disparity in prevalence of diabetic kidney disease in an Asian primary healthcare cluster

AIMS

Diabetic kidney disease (DKD) incidence is rising in Singapore. While measures to prevent onset and early detection of diabetes as well as optimal diabetes and blood pressure control are important, early detection and treatment of DKD at primary care are crucial to ameliorate its course. This study aimed to evaluate the prevalence of DKD in a primary care cluster in Singapore and identify its risk factors in a multi-ethnic Asian population.

METHODS

A total of 57,594 patients with type 2 diabetes mellitus (T2DM) followed-up at the National Healthcare Group Polyclinics with estimated glomerular filtration rate and at least two urine albumin/creatinine ratio (UACR) were stratified into DKD stages: normoalbuminuria (UACR <30 mg/g), microalbuminuria (MI, UACR 30-299 mg/g), macroalbuminuria (MA, ≥300 mg/g) and renal impairment (RI, estimated glomerular filtration rate eGFR <60 mL/min per 1.73 m(2)). Factors associated with DKD stages were evaluated.

RESULTS

Overall DKD prevalence (T2DM with MI, MA or RI) was high at 52.5%; 32.1% had MI, 5.3% had MA and 15.1% had RI. DKD prevalence within ethnic subpopulations was different: 52.2% of Chinese, 60.4% of Malays and 45.3% of Indians had DKD, respectively. Malays had a 1.42-fold higher DKD prevalence, while Indians had a 0.86-fold lower. Other independent risk factors were age, female gender, duration of diabetes and hypertension, HbA1c and body mass index.

CONCLUSION

The high prevalence of DKD and its interethnic differences suggest need for additional measures to optimize the care of T2DM at primary care to mitigate its progression.

A study of treatment adherence and quality of life among adults with chronic urticaria in Singapore

BACKGROUND

Chronic urticaria is a common skin condition that causes significant impact on patient's quality of life.

OBJECTIVE

The purpose of the study was to assess adherence to therapy and quality of life of patients with chronic urticaria. We also aimed to study the relationship of medication adherence and quality of life of patients with chronic urticaria.

METHODS

A cross sectional study was conducted with 103 patients from the dermatology clinic of National University Hospital, Singapore. Patients with chronic urticaria were asked to fill out a questionnaire for assessment of adherence to therapy and quality of life. We used the Morisky 8-Item Medication Adherence Scale to categorize adherence as high, medium, low. For assessment of quality of life, we used the validated chronic urticaria quality of life questionnaire (CU-Q2oL) by Bairadani et al.

RESULTS

The highest median scores for the items measuring quality of life were interference with sleep and pruritus. We also observed that the majority of patients (71.9%) had low adherence to medical therapy. No difference in adherence was noted in patients on once daily medication or more frequent dosing. There was no significant difference in the quality of life among patients with low and medium adherence to therapy.

CONCLUSION

Quality of life of patients with chronic urticaria does not depend on the patients' adherence to medications. Dosing frequency does not affect adherence in our study population. It is also important to recognize the symptoms and issues most affecting quality of life of patients with chronic urticaria, so as to improve overall management.

Direct medical cost of stroke in Singapore

BACKGROUND

Globally, stroke is recognized as one of the main causes of long-term disability, accounting for approximately 5·7 million deaths each year. It is a debilitating and costly chronic condition that consumes about 2-4% of total healthcare expenditure.

AIMS

To estimate the direct medical cost associated with stroke in Singapore in 2012 and to determine associated predictors.

METHODS

The National Healthcare Group Chronic Disease Management System database was used to identify patients with stroke between the years 2006 and 2012. Estimated stroke-related costs included hospitalizations, accident and emergency room visits, outpatient physician visits, laboratory tests, and medications.

RESULTS

A total of 700 patients were randomly selected for the analyses. The mean annual direct medical cost was found to be S$12 473·7, of which 93·6% were accounted for by inpatient services, 4·9% by outpatient services, and 1·5% by A&E services. Independent determinants of greater total costs were stroke types, such as ischemic stroke (P = 0·005), subarachnoid hemorrhage (P < 0·001) and intracerebral haemorrhage (P < 0·001), shorter poststroke period, more than one complications (P = 0·045), and a greater number of comorbidities (P = 0·001).

CONCLUSION

There is a considerable economic burden associated with stroke in Singapore. The type of stroke, length of poststroke period, and stroke complications and comorbidities are found to be associated with the total costs. Efforts to reduce inpatient costs and to allocate health resources to focus on the primary prevention of stroke should become a priority.

Direct medical cost of type 2 diabetes in singapore

Due to the chronic nature of diabetes along with their complications, they have been recognised as a major health issue, which results in significant economic burden. This study aims to estimate the direct medical cost associated with type 2 diabetes mellitus (T2DM) in Singapore in 2010 and to examine both the relationship between demographic and clinical state variables with the total estimated expenditure. The National Healthcare Group (NHG) Chronic Disease Management System (CDMS) database was used to identify patients with T2DM in the year 2010. DM-attributable costs estimated included hospitalisations, accident and emergency (A&E) room visits, outpatient physician visits, medications, laboratory tests and allied health services. All charges and unit costs were provided by the NHG. A total of 500 patients with DM were identified for the analyses. The mean annual direct medical cost was found to be $2,034, of which 61% was accounted for by inpatient services, 35% by outpatient services, and 4% by A&E services. Independent determinants of total costs were DM treatments such as the use of insulin only (p<0.001) and the combination of both oral medications and insulin (p=0.047) as well as having complications such as cerebrovascular disease (p<0.001), cardiovascular disease (p=0.002), peripheral vascular disease (p=0.001), and nephropathy (p=0.041). In this study, the cost of DM treatments and DM-related complications were found to be strong determinants of costs. This finding suggests an imperative need to address the economic burden associated with diabetes with urgency and to reorganise resources required to improve healthcare costs.

A matched-group study protocol to evaluate the implementation of an Integrated Care Pathway programme for chronic obstructive pulmonary disease in Singapore

INTRODUCTION

The treatment of chronic obstructive pulmonary disease (COPD) involves different care providers across care sites. This fragmentation of care increases the morbidity and mortality burden, as well as acute health services use. The COPD-Integrated Care Pathway (ICP) was designed and implemented to integrate the care across different sites from primary care to acute hospital and home. It aims to reduce the prevalence of COPD among the population in the catchment, reduce risk of hospital admissions, delay or prevent the progression of the disease and reduce mortality rate by adopting a coordinated and multidisciplinary approach to the management of the patients' medical conditions. This study on the COPD-ICP programme is undertaken to determine the impact on processes of care, clinical outcomes and acute care utilisation.

METHODS AND ANALYSIS

This will be a retrospective, pre-post, matched-groups study to evaluate the effectiveness of the COPD-ICP programme in improving clinical outcomes and reducing healthcare costs. Programme enrolees (intervention group) and non-enrolees (comparator group) will be matched using propensity scores. Administratively, we set 30% as our target for proportion admission difference between programme and non-programme patients. A sample size of 62 patients in each group will be needed for statistical comparisons to be made at 90% power. Adherence with recommended care elements will be measured at baseline and quarterly during 1-year follow-up. Risk of COPD-related hospitalisations as primary outcome, healthcare costs, disease progression and 1-year mortality during 1-year follow-up will be compared between the groups using generalised linear regression models.

ETHICS AND DISSEMINATION

This protocol describes the implementation and proposed evaluation of the COPD-ICP programme. The described study has received ethical approval from the NHG Domain Specific Review Board (DSRB Ref: 2013/01200). Results of the study will be reported through peer-review publications and presentations at healthcare conferences.

Validity and reliability of a self-reported measure of medication adherence in patients with Type 2 diabetes mellitus in Singapore

AIMS

A reliable and valid measure is essential for the assessment of medication adherence. Until now, no patient-reported medication adherence measure has been validated in Singapore. The aim of this study was to validate a modified 4-item Morisky-Green-Levine Medication Adherence Scale in patients with Type 2 diabetes in Singapore.

METHODS

A cross-sectional survey was conducted in a sample of outpatients with Type 2 diabetes in Singapore from September to December in 2009. Respondents completed either an English or Chinese version of the modified 4-item Morisky-Green-Levine Medication Adherence Scale. The scale scores ranged from 0 to 4, with higher scores indicating better medication adherence. Reliability was assessed using Cronbach's alpha. Content validity was assessed by expert review. Construct validity was examined using factor analysis and hypothesis testing.

RESULTS

Of the 294 respondents who completed the modified Morisky-Green-Levine Medication Adherence Scale, 13.3, 21.4, 35.7 and 29.6% had a score of 0-1, 2, 3 and 4, respectively. The internal consistency of the scale was moderate (Cronbach's alpha = 0.62). Principal component analysis showed that the four items loaded onto one factor (eigenvalue = 1.95). Respondents with higher scores were older (P < 0.001), had lower HbA(1c) levels (P < 0.001) and had better adherence to physician-recommended diet (P < 0.001) and physical exercise (P = 0.02).

CONCLUSIONS

The psychometric properties of the modified Morisky-Green-Levine Medication Adherence Scale were less than satisfactory. A ceiling effect was observed. The scale may not be an adequate measure to assess medication adherence in patients with Type 2 diabetes in Singapore. Future research could target refining the scale and investigating its use in other patient populations.

Health-related quality of life and glycaemic control in patients with Type 2 diabetes mellitus in Singapore

AIMS

To investigate the health-related quality of life of patients with diabetes mellitus in Singapore and its associations with diabetes-related characteristics and glycaemic control.

METHODS

An interviewer-administered, cross-sectional survey was conducted in a sample of 301 adult diabetes patients under primary care. The survey questionnaire included both a generic health-related quality of life measure, the Euroqol 5-D and a diabetes-specific instrument, the Audit of Diabetes-dependent Quality of Life. Patients' most recent HbA(1c) values were extracted from their medical records.

RESULTS

After excluding patients who lacked the 90-day HbA(1c) test result, the final number of responses analysed was 282. Pain/discomfort was the most common complaint among the five Euroqol 5-D domains (by 28.0% of the respondents). Lack of freedom to eat was the Audit of Diabetes-dependent Quality of Life domain with the greatest negative average weighted impact (= -3.8, on a scale of -9 to 3). A significant association was observed between Audit of Diabetes-dependent Quality of Life average weighted impact and both duration of diabetes and use of insulin. A negative correlation was found between health-related quality of life and HbA(1c) values in both health-related quality of life measures (both r=-0.2, P=0.001).

CONCLUSIONS

Patients with diabetes in primary-care settings frequently reported problems with pain/discomfort and restrictions in diet. Poorer health-related quality of life was found to be associated with higher HbA(1c) values. The chronicity of diabetes and insulin therapy may have a negative impact on patients' diabetes-related health-related quality of life. This study indicates the importance of achieving better disease management to improve the health-related quality of life of patients with diabetes.

Progression rate of newly diagnosed impaired fasting glycemia to type 2 diabetes mellitus: a study using the National Healthcare Group Diabetes Registry in Singapore

BACKGROUND

The aims of the present study were to estimate the rate of progression from newly diagnosed impaired fasting glycemia (IFG) to type 2 diabetes mellitus (T2DM) in Singapore and to identify factors associated with the progression to T2DM in individuals with newly diagnosed IFG.

METHODS

The present study was a retrospective cohort study of newly diagnosed IFG from the National Healthcare Group Diabetes Registry between 1 January 2006 and 31 December 2007 to estimated the rate of progression to T2DM. Univariate survival analysis, followed by multivariate survival analysis, was performed and interactions were tested in the final model.

RESULTS

Over a mean follow-up period of 1.65 ± 0.13 years, 85 of 490 participants with newly diagnosed IFG developed T2DM, giving an annual progression rate of 6.8%. The factors associated with the development of T2DM were higher fasting plasma glucose level in the year of IFG diagnosis (hazard ratio [HR] = 14.6; 95% confidence interval [CI] 5.66-37.5), Chinese race (HR = 2.70; 95% CI 1.44-5.06), and body mass index (HR = 1.11; 95% CI, 1.06-1.15).

CONCLUSIONS

The progression rate to T2DM is high in subjects with newly diagnosed IFG. Intensive lifestyle modification can be incorporated into their current yearly follow-up to prevent progression to T2DM, which is a growing problem in Singapore.

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.

Healthcare workers and H1N1 vaccination: does having a chronic disease make a difference?

Introduction

A novel H1N1 vaccine was manufactured in response to the pandemic in 2009. This study describes the willingness to be vaccinated for H1N1 among healthcare workers (HCWs) in primary healthcare clinics with and without chronic medical conditions, their reasons for refusing vaccination and whether they sought additional information to make an informed decision for the vaccination.

Materials and methods

An anonymous survey was conducted in November 2009 among all medical, nursing, allied health and operations HCWs in nine primary care clinics in Singapore. Participants were asked if they had any chronic medical conditions associated with influenza-related complications (example: asthma, stroke, heart disease, cancer, diabetes mellitus, renal disease), their perception towards vaccination for H1N1 and against seasonal influenza within the preceding 2 years.

Results

The initial response rate was 80%, of which 711 (54.7%) of the completed surveys were analysed. Among the 711 respondents, 16.6% reported having at least 1 chronic disease. Asthma (10.8%), hypertension (10.4%) and dyslipidaemia (9.8%) were the main chronic conditions. Only 39.4% of respondents were willing to be vaccinated against H1N1. Males were 2.07 (95% CI 1.19–3.62) times more likely than females to receive the H1N1 vaccination; the 45–54 and 55+ years old were 2.12 (95% CI 1.06–4.24) and 2.44 (95% CI 1.13–5.27) times more willing than those below 25 years old; and those who considered accepting the seasonal influenza vaccine were 7.0 times more likely than those who did not (95%CI 4.48–10.92). The 2 principal barriers were “fear of side effects” and “unsure of vaccine's effectiveness”. Although 78% attended some H1N1-related talks, only 7% of all HCWs felt that they had sufficient information. Most wanted more information about the vaccine's safety profile and contraindications.

Conclusion

Fewer than 40% of HCWs expressed willingness to receive the H1N1 vaccination, lower than past rates of influenza vaccine. HCWs in primary care clinics who had a chronic condition did not perceive themselves to be at higher risk of developing H1N1-related complications and were not more willing than the rest of the HCWs to accept H1N1 vaccination. Vaccine's side effects and effectiveness were the main concerns. Uptake of H1N1 vaccine may improve with targeted health information covering the vaccine's safety profile.

Development and validation of a general health literacy test in Singapore

Due to the concern of equating correct pronunciation with comprehension and the differences in health care systems, existing health literacy (HL) instruments may not be appropriate for or applicable to English-speaking countries other than the USA. The purpose of this study was to develop and validate the Health Literacy Test for Singapore (HLTS), which is an adapted version of the Short-Test of Functional Health Literacy in Adults. Three hundred and two patients were interviewed and administered the HLTS, the Newest Vital Sign (NVS), a demographic questionnaire, and a knowledge test of chronic diseases. The convergent validity of HLTS was determined by examining the association between HLTS and NVS HL levels, whereas predictive validity was tested by examining the difference in knowledge of chronic conditions between the two HLTS HL (i.e. adequate and inadequate HL) groups. Bivariate correlation of HLTS HL levels with age and education was assessed to test a priori hypotheses that patients with inadequate HL were older and less educated. The results showed that HLTS displayed good internal reliability (Cronbach's alpha = 0.87). The correlation between HLTS and NVS was moderate (γ = 0.55; P = 0.005) and individuals with inadequate HL were older (P = 0.002) and less educated (P = 0.007). In addition, patients with adequate HL had a higher mean score on the chronic disease knowledge test (P = 0.036). In conclusion, the HLTS is a valid and reliable measure for assessing Singaporeans ability to read and comprehend health-related materials written in English.

Impact of diabetes mellitus (DM) on the health-care utilization and clinical outcomes of patients with stroke in Singapore

OBJECTIVE

This study aims to assess the impact of diabetes mellitus (DM) on the health-care utilization and clinical outcomes of patients with acute stroke.

METHODS

This is a retrospective cohort study. All patients who were admitted for the first time to one of the three public hospitals in the National Healthcare Group in Singapore from January 2005 to June 2007 with a primary diagnosis of acute stroke were included and were followed up for 1 year after the index hospitalization. The study population was divided into two groups: with DM and without DM. Both univariate and multivariate analyses were applied to compare the hospital length of stay (LOS), hospitalization costs, mortality, as well as the 1-year hospital readmissions between the DM and non-DM groups.

RESULTS

There were 9766 study patients, and 38.5% of them had DM. DM patients with ischemic stroke (IS) and transient ischemic attack (TIA) stayed 1-day and 0.6-day longer, and incurred 10% and 26% higher hospital cost during index admission, respectively, compared with their counterparts in the non-DM group. They also had more hospital readmission within 1 year. The mortality rate in IS patients with diabetes was 24% higher. After risk adjustment, subarachnoid hemorrhage patients with diabetes had more hospitalizations. Intracerebral hemorrhage (ICH) and IS patients in the DM group had all worse outcomes but the 1-year stroke recurrence; TIA patients with DM incurred longer LOS and hospital costs.

CONCLUSION

DM predicts worse clinical outcomes and higher health-care expenditures in the 1-year poststroke especially for the IS, ICH, and TIA stroke subtypes.

A preliminary evaluation of a disease management programme for patients with diabetes mellitus and hypertension in a primary healthcare setting

INTRODUCTION

The Comprehensive Chronic Care Programme (CCCP) is an intensified programme designed to provide comprehensive care for the management of diabetes mellitus, hypertension and hyperlipidaemia at a primary healthcare setting. A formative study was done to evaluate the effectiveness of the CCCP compared to the normal polyclinic management of diabetes mellitus.

MATERIALS AND METHODS

Control of diabetes (HbA1c) and hypertension (blood pressure) in 63 diabetic patients of a pilot CCCP was compared with 100 diabetic patients not on the programme (non-CCCP) after a 6-month follow-up. Paired t-tests were conducted for differences in mean HbA1c values between baseline and after 6 months. The H-rank test was applied to check for significant differences in change categories of hypertension control between CCCP and non-CCCP cases.

RESULTS

In the CCCP group, there was a two-point decrease in HbA1c after 6 months and 65.1% of the patients showed improvement. The proportion of patients achieving optimal diabetic control increased from 9.5% to 36.5%. Conversely, there was deterioration in the non-CCCP group with decrease in the proportion of patients achieving optimal diabetic control from 31% to 21%. Of the hypertensive patients in the CCCP group, 54.5% showed an improvement in blood pressure (BP) control while 44% of the non-CCCP group showed improvement at 6 months.

CONCLUSIONS

CCCP, a comprehensive chronic disease management programme, is effective for good diabetic control of patients with diabetes mellitus.