Wern Ee Tang

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

Diabet. Med. 29, e241–e248 (2012)

High normal albuminuria is independently associated with aortic stiffness in patients with Type 2 diabetes

High normal albuminuria is associated with higher cardiovascular risk in patients with diabetes. Increased aortic stiffness is an established risk factor of vascular events. However, the relationship between albuminuria within the normal range (0–30 mg/g) and aortic stiffness in patients with Type 2 diabetes is unknown.

Perceptions of insulin therapy amongst Asian patients with diabetes in Singapore

Diabet. Med. 28, 206–211 (2011)

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 (Cronbachs 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.

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

Diabet. Med. 29, e338–e344 (2012)

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

Abstract 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 vaccines 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 vaccines 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. Vaccines side effects and effectiveness were the main concerns. Uptake of H1N1 vaccine may improve with targeted health information covering the vaccines safety profile.

Vascular cell adhesion molecule-1, but not intercellular adhesion molecule-1, is associated with diabetic kidney disease in Asians with type 2 diabetes

BACKGROUND AND AIMS The association of adhesion molecules ICAM-1 and VCAM-1 with cardiovascular diseases has been well-studied. However, their roles in diabetic kidney disease (DKD) are incompletely understood. We aim to study the association of plasma ICAM-1 and VCAM-1 with DKD in Asians with type 2 diabetes (T2DM). SUBJECTS AND METHODS A total of 1950 Asians with T2DM were included in this cross-sectional study. Plasma ICAM-1 and VCAM-1 were measured by immunoassays. RESULTS Renal filtration function (eGFR) declined and urinary albumin-to-creatinine ratio (ACR) levels increased progressively with the increase in plasma VCAM-1 levels. In contrast, no significant changes in eGFR and ACR were observed in subjects across different plasma ICAM-1 levels. Both ICAM-1 and VCAM-1 were correlated with ACR (rho = 0.153, p < 0.001 for VCAM-1 and ACR; rho = 0.053, p = 0.020 for ICAM-1 and ACR) in bivariate correlation analysis. However, only VCAM-1 was correlated with eGFR (rho = -0.228, p < 0.001). Multivariable linear regression models revealed that VCAM-1, but not ICAM-1, was independently associated with eGFR and albuminuria. Backward linear regression suggested that plasma VCAM-1 variability was mainly determined by eGFR whereas plasma ICAM-1 level was mainly determined by C-reactive protein in patients with T2DM. CONCLUSIONS Plasma VCAM-1 level, but not ICAM-1 level, was independently associated with prevalent DKD in Asians with T2DM. High level of ICAM-1 may be indicative of systemic inflammation and portends increase risk of incipient DKD.

Ethnic disparity in central arterial stiffness and its determinants among Asians with type 2 diabetes

OBJECTIVE We previously reported ethnic disparity in adverse outcomes among Asians with type 2 diabetes (T2DM) in Singapore. Central arterial stiffness can aggravate systemic vasculopathy by propagating elevated systolic and pulse pressures forward, thereby accentuating global vascular injury. We aim to study ethnic disparity in central arterial stiffness and its determinants in a multi-ethnic T2DM Asian cohort. METHODS Arterial stiffness was estimated by carotid-femoral pulse wave velocity (PWV) and augmentation index (AI) using applanation tonometry method in Chinese (N = 1045), Malays (N = 458) and Indians (N = 468). Linear regression model was used to evaluate predictors of PWV and AI. RESULTS PWV was higher in Malays (10.1 ± 3.0 m/s) than Chinese (9.7 ± 2.8 m/s) and Indians (9.6 ± 3.1 m/s) (P = 0.018). AI was higher in Indians (28.1 ± 10.8%) than Malays (25.9 ± 10.1%) and Chinese (26.1 ± 10.7%) (P < 0.001). Malays remain associated with higher PWV (β = 0.299, P = 0.048) post-adjustment for age, gender, duration of diabetes, hemoglobin A1c, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), soluble receptor for advanced glycation end-products, urinary albumin-to-creatinine ratio, and insulin usage, which were all independent predictors of PWV. Indians remain associated with higher AI (β = 2.776, P < 0.001) post-adjustment for age, gender, BMI, SBP, DBP, and height, which were independent predictors of AI. These variables explained 27.7% and 33.4% of the variance in PWV and AI respectively. CONCLUSIONS Malays and Indians with T2DM have higher central arterial stiffness, which may explain their higher risk for adverse outcomes. Modifying traditional major vascular risk factors may partially alleviate their excess cardiovascular risk through modulating arterial stiffness.

Genetic variants in the receptor for advanced glycation end products (RAGE) gene were associated with circulating soluble RAGE level but not with renal function among Asians with type 2 diabetes: a genome-wide association study.

Background The soluble receptor for advanced glycation end products (sRAGE) has been shown to play an important role in diabetic complications. We conducted genome-wide association study (GWAS) of sRAGE in Asian type 2 diabetes mellitus (T2DM) patient and validated the association in an independent cohort of T2DM. Methods GWAS for sRAGE was performed in 2058 T2DM patients. Associations between single-nucleotide polymorphisms (SNPs) and plasma sRAGE level were analyzed in an additive model using a linear mixed model. To validate the associations, we performed de novo genotyping in an independent cohort (n = 1984). We selected the top SNP for assessment with diabetic kidney disease (DKD). Results The strongest SNP, rs2070600C>T (P = 1.21 × 10-52), was a genotyped, missense SNP located on chromosome 6, corresponding to the RAGE (AGER) gene locus, the gene encoding RAGE. Conditioning analysis on rs2070600 revealed that rs2071288C>T was the top genotyped independent SNP (P = 8.36 × 10-10). Both SNPs were strongly and dose-dependently correlated with sRAGE level (TT = 399.6 pg/mL, CT = 737.0 pg/mL and CC = 967.0 pg/mL, P < 0.001 for rs2070600; TT = 687.9 pg/mL, CT = 737.6 pg/mL and CC = 904.7 pg/mL, P < 0.001 for rs2072188). Both SNPs were robustly replicated in the independent cohort, especially among Chinese patients (P = 9.02 × 10-72 for rs2070600; P = 1.13 × 10-9 for rs2071288). Log-transformed sRAGE was associated with DKD after adjustment for age, gender and ethnicity in pooled cohorts [odds ratio 2.536 (95% confidence interval 1.864-3.450), P < 0.001]. However, we did not observe any significant association between rs2070600 and DKD. Conclusions Common variants in RAGE are strongly associated with plasma sRAGE level, which is associated with DKD. However, we did not find a causal link between sRAGE and renal function by Mendelian randomization.

Arterial stiffness is an independent predictor for albuminuria progression among Asians with type 2 diabetes—A prospective cohort study

AIM Albuminuria progression has been associated with renal deterioration in type 2 diabetes (T2DM). Central arterial stiffness can aggravate systemic vasculopathy by propagating elevated systolic and pulse pressures forward, thereby accentuating global vascular injury. We aim to investigate whether central arterial stiffness is an independent predictor for albuminuria progression in a multi-ethnic T2DM Asian cohort in Singapore. METHODS In a prospective cohort, 1012 T2DM patients were assessed at baseline and after a median follow-up of 3.1years. 880 patients with baseline normo- (urinary albumin-to-creatinine ratio (ACR)<30mg/g, n=579) and microalbuminuria (ACR=30-299mg/g, n=301) were divided into progression and non-progression groups according to ACR changes. Progression was defined as transition from normo- to microalbuminuria, micro- to macroalbuminuria, or normo- to macroalbuminuria. Central arterial stiffness was estimated by carotid-femoral pulse wave velocity (PWV) using applanation tonometry method. Stepwise multiple regression analysis was used to determine the predictor(s) for albuminuria progression. RESULTS Albuminuria progression occurred in 178 patients (20.2%). Baseline PWV was higher in progression (10.1±2.9m/s) than non-progression group (9.2±2.4m/s, p<0.001). 1-SD increase in baseline PWV was associated with albuminuria progression (OR=1.457, 95% CI, 1.236-1.718, p<0.001). Stepwise regression analysis identified that baseline PWV (OR=1.241, 95% CI, 1.033-1.490, p=0.021), BMI (OR=1.046, 95% CI, 1.012-1.080, p=0.008), nature log-transformed estimated glomerular filtration rate (LneGFR) (OR=0.320, 95% CI, 0.192-0.530, p=0.010) and LnACR (OR=1.344, 95% CI, 1.187-1.522, p=0.008) are predictors for albuminuria progression. CONCLUSION Increased central arterial stiffness at baseline predicted future progression of albuminuria. Our results suggest the potential benefit of ameliorating central arterial stiffness to retard albuminuria progression in T2DM.