Associations of comorbid depression with cardiovascular-renal events and all-cause mortality accounting for patient reported outcomes in individuals with type 2 diabetes: a 6-year prospective analysis of the Hong Kong Diabetes Register.

Background: Psychosocial status and patient reported outcomes (PRO) [depression and health-related quality-of-life (HRQoL)] are major health determinants. We investigated the association between depression and clinical outcomes in Chinese patients with type 2 diabetes (T2D), adjusted for PRO. Methods: Using prospective data from Hong Kong Diabetes Register (2013-2019), we estimated the hazard-ratio (HR, 95%CI) of depression (validated Patient Health Questionnaire 9 (PHQ-9) score≥7) with incident cardiovascular disease (CVD), ischemic heart disease (IHD), chronic kidney disease (CKD: eGFR<60 ml/min/1.73m2) and all-cause mortality in 4525 Chinese patients with T2D adjusted for patient characteristics, renal function, medications, self-care and HRQoL domains (mobility, self-care, usual activities, pain/discomfort, anxiety/depression measured by EQ-5D-3L) in linear-regression models. Results: In this cohort without prior events [mean ± SD age:55.7 ± 10.6, 43.7% women, median (IQR) disease duration of 7.0 (2.0-13.0) years, HbA1c, 7.2% (6.6%-8.20%), 26.4% insulin-treated], 537(11.9%) patients had depressive symptoms and 1923 (42.5%) patients had some problems with HRQoL at baseline. After 5.6(IQR: 4.4-6.2) years, 141 patients (3.1%) died, 533(11.8%) developed CKD and 164(3.6%) developed CVD. In a fully-adjusted model (model 4) including self-care and HRQoL, the aHR of depression was 1.99 (95% confidence interval CI):1.25-3.18) for CVD, 2.29 (1.25-4.21) for IHD. Depression was associated with all-cause mortality in models 1-3 adjusted for demographics, clinical characteristics and self-care, but was attenuated after adjusting for HRQoL (model 4- 1.54; 95%CI: 0.91-2.60), though HR still indicated same direction with important magnitude. Patients who reported having regular exercise (3-4 times per week) had reduced aHR of CKD [0.61 (0.41-0.89)]. Item 4 of PHQ-9 (feeling tired, little energy) was independently associated with all-cause mortality with aHR of 1.66 (1.30-2.12). Conclusion: Depression exhibits significant association with CVD, IHD, and all-cause mortality in patients with diabetes, adjusting for their HRQoL and health behaviors. Despite the association between depression and all-cause mortality attenuated after adjusting for HRQoL, the effect size remains substantial. The feeling of tiredness or having little energy, as assessed by item Q4 of the PHQ-9 questionnaire, was found to be significantly associated with an increased risk of all-cause mortality after covariate adjustments. Our findings emphasize the importance of incorporating psychiatric evaluations into holistic diabetes management.

Clinical outcomes following discontinuation of metformin in patients with type 2 diabetes and advanced chronic kidney disease in Hong Kong: a territory-wide, retrospective cohort and target trial emulation study.

Background: Current labelling advises discontinuation of metformin when estimated glomerular filtration rate (eGFR) < 30 ml/min/1.73 m2 due to increased risk of lactic acidosis. However, in real-world practice, the risk-benefit ratios remain uncertain. We examined the risk associations of discontinued-metformin use with cardiorenal and clinical outcomes in patients with type 2 diabetes (T2D) and advanced chronic kidney disease. Methods: In this territory-wide, retrospective cohort and target trial emulation study, we included Chinese patients attending the Hong Kong Hospital Authority (HA) and enrolled in the Risk-Assessment-and-Management-Programme-for-Diabetes-Mellitus (RAMP-DM) from 2002 to 2019. Patients were stratified by discontinuation of metformin within six months after reaching eGFR < 30 ml/min/1.73 m2 from January 1, 2002 to December 31, 2018, and followed up until December 31 2019. We excluded patients who had observational time <6 months from eGFR < 30 ml/min/1.73 m2, and had their eGFR measured during a hospitalisation episode due to acute kidney injury, or missing diagnosis date of diabetes. We compared the risk associations of metformin discontinuation with clinical outcomes. The primary outcomes were major adverse cardiovascular events (MACE), end-stage kidney disease (ESKD), cancer, and all-cause mortality. A Cox-model with time-dependent exposure and covariates was used to estimate the hazard ratio (HR) of outcomes in a propensity-score overlap-weighted cohort. The risk of occurrence of lactic acidosis (serum lactate > 5.0 mmol/L with a concomitant blood pH < 7.35 or ICD-9 codes of 276.2) in discontinued-metformin versus continued-metformin users was assessed in a separate register-based cohort. Findings: A total of 33,586 metformin users with new-onset eGFR < 30 ml/min/1.73 m2 were included in the study, 7500 (22.3%) of whom discontinued metformin within 6 months whereas 26,086 (77.7%) continued use of metformin. During a median follow-up of 3.8 (IQR: 2.2-6.1) years, 16.4% (5505/33,586), 30.1% (10,113/33,586), and 7.1% (2171/30,682) had incident MACE, ESKD, and cancer respectively, and 44.4% (14,917/33,586) died. Compared to continued-metformin use, discontinuation was associated with higher risk of MACE (weighted and adjusted HR = 1.40, 95% CI: 1.29-1.52), ESKD (HR = 1.52, 1.42-1.62), and death (HR = 1.22, 1.18-1.27). No association was observed for cancer (HR = 0.93, 0.85-1.01). Discontinued-metformin users had higher change in HbA1c change at 6-month of follow-up versus continued-metformin users (weighted mean HbA1c level change: 0.5% [0.4-0.6%] versus 0.2% [0.1-0.2]). In the separate register-based cohort (n = 3235), null association was observed between metformin use and risk of lactic acidosis (weighted HR = 0.94 [0.53-1.64]). Interpretation: Our results suggest that discontinuation of metformin in patients with T2D and chronic kidney disease may be associated with increased risk of cardiovascular-renal events. Use of metformin below eGFR of 30 ml/min/1.73 m2 may be associated with cardiovascular, renal, and mortality benefits that need to be weighed against the risk of lactic acidosis, but further research is needed to validate these findings. Funding: CUHK Impact Research Fellowship Scheme.

Health impacts of new-onset diabetes in women post-gestational diabetes mellitus: Insights from Hong Kong's territory-wide data.

AIMS/INTRODUCTION: To determine the population health burden attributable to the development of diabetes among women with a history of gestational diabetes mellitus (GDM). MATERIALS AND METHODS: We conducted a retrospective analysis of women with a history of GDM attending the Hong Kong Hospital Authority between 2000 and 2019. The time-varying population attributable fraction was calculated. RESULTS: A total of 76,181 women with a history of gestational diabetes mellitus were included, 6,606 of them developed diabetes during a median follow-up of 8.6 years. The respective hazard ratios (95% confidence interval) among women with GDM who developed diabetes vs those with GDM only were 2.8 (2.2, 3.7) for cardiovascular disease (CVD), 4.8 (3.0, 7.7) for end-stage kidney disease (ESKD), 2.2 (1.9, 2.6) for infection-related hospitalization, and 1.8 (1.3, 2.4) for all-cause mortality. The development of diabetes was associated with 1.3 (0.8, 1.7), 0.6 (0.3, 0.8), 3.2 (2.4, 4.0), and 0.5 (0.2, 0.9) additional incident cases per 1,000 person-years, accounting for 24.0% (13.2%, 35.9%), 42.0% (22.5%, 58.8%), 10.8% (7.1%, 14.9%), and 6.0% (-3.1%, 16.1%) of absolute number of CVD, ESKD, infection-related hospitalization, and all-cause mortality over 20 years after GDM, respectively. CONCLUSIONS: Diabetes is a significant contributor to the population health burden of some clinical outcomes in women with a history of gestational diabetes mellitus, but other risk factors need to be considered.

Treatment for type 2 diabetes and diabetic nephropathy by targeting Smad3 signaling.

TGF-ß/Smad3 signaling plays a critical role in type 2 diabetes (T2D) and type 2 diabetic nephropathy (T2DN), but treatment by specifically targeting Smad3 remains unexplored. To develop a new Smad3-targeted therapy for T2D and T2DN, we treated db/db mice at the pre-diabetic or established diabetic stage with a pharmacological Smad3 inhibitor SIS3. The therapeutic effect and mechanisms of anti-Smad3 treatment on T2D and T2DN were investigated. We found that anti-Smad3 treatment on pre-diabetic db/db mice largely attenuated both T2D and T2DN by markedly reducing blood glucose levels, and inhibiting the elevated serum creatinine, microalbuminuria, and renal fibrosis and inflammation. Unexpectedly, although SIS3 treatment on the established diabetic db/db mice inhibited T2DN but did not significantly improve T2D. Mechanistically, we uncovered that inhibition of T2DN in SIS3-treated db/db mice was associated with effectively restoring the balance of TGF-ß/Smad signaling by inhibiting Smad3 while increasing Smad7, thereby suppressing Smad3-mediated renal fibrosis and NF-κB-driven renal inflammation via lncRNA Erbb4-IR and LRN9884-dependent mechanisms. We also revealed that inhibition of islet ß cell injury by preventing the loss of islet Pax 6 could be the mechanism through which the pre-diabetic treatment, rather than the late SIS3 treatment on db/db mice significantly improved the T2D phenotype.

Reduced methylation correlates with diabetic nephropathy risk in type 1 diabetes.

Diabetic nephropathy (DN) is a polygenic disorder with few risk variants showing robust replication in large-scale genome-wide association studies. To understand the role of DNA methylation, it is important to have the prevailing genomic view to distinguish key sequence elements that influence gene expression. This is particularly challenging for DN because genome-wide methylation patterns are poorly defined. While methylation is known to alter gene expression, the importance of this causal relationship is obscured by array-based technologies since coverage outside promoter regions is low. To overcome these challenges, we performed methylation sequencing using leukocytes derived from participants of the Finnish Diabetic Nephropathy (FinnDiane) type 1 diabetes (T1D) study (n = 39) that was subsequently replicated in a larger validation cohort (n = 296). Gene body-related regions made up more than 60% of the methylation differences and emphasized the importance of methylation sequencing. We observed differentially methylated genes associated with DN in 3 independent T1D registries originating from Denmark (n = 445), Hong Kong (n = 107), and Thailand (n = 130). Reduced DNA methylation at CTCF and Pol2B sites was tightly connected with DN pathways that include insulin signaling, lipid metabolism, and fibrosis. To define the pathophysiological significance of these population findings, methylation indices were assessed in human renal cells such as podocytes and proximal convoluted tubule cells. The expression of core genes was associated with reduced methylation, elevated CTCF and Pol2B binding, and the activation of insulin-signaling phosphoproteins in hyperglycemic cells. These experimental observations also closely parallel methylation-mediated regulation in human macrophages and vascular endothelial cells.

AANG Prevents Smad3-dependent Diabetic Nephropathy by Restoring Pancreatic ß-Cell Development in db/db Mice.

Diabetic nephropathy (DN) is a major cause of end-stage kidney disease, where TGF-ß1/Smad signaling plays an important role in the disease progression. Our previous studies demonstrated a combination of Traditional Chinese Medicine derived Smad7 agonist Asiatic Acid (AA) and Smad3 inhibitor Naringenin (NG), AANG, effectively suppressed the progression of renal fibrosis in vivo. However, its implication in type-2 diabetic nephropathy (T2DN) is still unexplored. Here, we detected progressive activation of Smad3 but reduction of Smad7 in db/db mice during T2DN development. Therefore, we optimized the dosage and the combination ratio of AANG to achieve a better rebalancing Smad3/Smad7 signaling for treatment of T2DN. Unexpectedly, preventive treatment with combined AANG from week 4 before the development of diabetes and T2DN effectively protected against the onset of T2DN. In contract, these inhibitory effects were lost when db/db mice received the late AANG treatment from 12-24 weeks. Surprisingly, preventive treatment with AANG ameliorated not only T2DN but also the primary disease type-2 diabetes (T2D) with relative normal levels of fasting blood glucose and HbA1c, and largely improving metabolic abnormalities especially on insulin insensitivity and glucose tolerance in db/db mice. Mechanistically, AANG effectively prevented both Smad3-mediated renal fibrosis and NF-κB-driven renal inflammation in the diabetic kidney in vivo and advanced glycation end-products (AGE) stimulated tubular epithelial mTEC cells in vitro. More importantly, we uncovered that preventive treatment with AANG effectively protected against diabetic-associated islet injury via restoring the ß cell development in db/db mice. Taken together, we discovered that the early treatment with combined AANG can effectively protect against the development of T2D and T2DN via mechanism associated with protection against Smad3-depenedent islet injury.

Time-varying risk associations of renin angiotensin system inhibitors with pneumonia and related deaths in a cohort of 252,616 patients with diabetes (2002-2019).

AIMS: To evaluate the time-varying and cumulative risk associations of renin-angiotensin-system-inhibitors (RASi) with pneumonia and related deaths in people with diabetes. METHODS: This was a prospective analysis with propensity-score overlap-weighting of a territory-wide cohort (n = 252,616, 1.7 million person-years) and a register-based cohort (n = 13,017, 0.1 million person-years) of patients with diabetes in Hong Kong. We compared risk of pneumonia and related death in new-users of angiotensin-converting-enzyme-inhibitor (ACEi) and angiotensin-receptor-blocker (ARBs) with non-RASi users and new-users of calcium-channel-blockers as active comparator. RESULTS: Amongst 252,616 people with diabetes (99.3% type 2 diabetes) in the population-based cohort with a mean follow-up of 6.7 years, 73,161 were new-ACEi-only users; 20,907 new-ARBs-only users; 38,778 ACEi/ARBs users; and 119,770 never-ACEi/ARBs. Time-varying RASi exposure was associated with reduced risk of pneumonia (HR = 0.78, 95% CI: 0.75-0.82) and pneumonia-related death (HR = 0.49, 0.46-0.53). The respective HRs for ARBs-only were 0.70 (0.62-0.78) and 0.41 (0.33-0.52) and that of ACEi-only were 0.98 (0.91-1.05) and 0.77 (0.68-86). The attenuated risk association of RASi use was time-invariant for pneumonia (P = 0.340) and time-varying for related-death (P < 0.001) with prevention of 0.6 (0.2-0.9) and 1.4 (1.0-1.6) per-1000-person-years events and deaths, respectively. CONCLUSIONS: Long-term use of RASi, notably ARBs, was associated with reduced risk of pneumonia and related deaths in Chinese people with diabetes.

Smad3 deficiency improves islet-based therapy for diabetes and diabetic kidney injury by promoting ß cell proliferation via the E2F3-dependent mechanism.

Rationale: Poor ß cell proliferation is one of the detrimental factors hindering islet cell replacement therapy for patients with diabetes. Smad3 is an important transcriptional factor of TGF-ß signaling and has been shown to promote diabetes by inhibiting ß cell proliferation. Therefore, we hypothesize that Smad3-deficient islets may be a novel cell replacement therapy for diabetes. Methods: We examined this hypothesis in streptozocin-induced type-1 diabetic mice and type-2 diabetic db/db mice by transplanting Smad3 knockout (KO) and wild type (WT) islets under the renal capsule, respectively. The effects of Smad3KO versus WT islet replacement therapy on diabetes and diabetic kidney injury were examined. In addition, RNA-seq was applied to identify the downstream target gene underlying Smad3-regulated ß cell proliferation in Smad3KO-db/db versus Smad3WT-db/db mouse islets. Results: Compared to Smad3WT islet therapy, treatment with Smad3KO islets produced a much better therapeutic effect on both type-1 and type-2 diabetes by significantly lowering serum levels of blood glucose and HbA1c and protected against diabetic kidney injuries by preventing an increase in serum creatinine and the development of proteinuria, mesangial matrix expansion, and fibrosis. These were associated with a significant increase in grafted ß cell proliferation and blood insulin levels, resulting in improved glucose intolerance. Mechanistically, RNA-seq revealed that compared with Smad3WT-db/db mouse islets, deletion of Smad3 from db/db mouse islets markedly upregulated E2F3, a pivotal regulator of cell cycle G1/S entry. Further studies found that Smad3 could bind to the promoter of E2F3, and thus inhibit ß cell proliferation via an E2F3-dependent mechanism as silencing E2F3 abrogated the proliferative effect on Smad3KO ß cells. Conclusion: Smad3-deficient islet replacement therapy can significantly improve both type-1 and type-2 diabetes and protect against diabetic kidney injury, which is mediated by a novel mechanism of E2F3-dependent ß cell proliferation.

Skin autofluorescence is associated with progression of kidney disease in type 2 diabetes: A prospective cohort study from the Hong Kong diabetes biobank.

BACKGROUND AND AIMS: Skin autofluorescence (SAF) can non-invasively assess the accumulation of tissue AGEs. We investigated the association between SAF and kidney dysfunction in participants with T2D. METHODS: Of 4030 participants consecutively measured SAF at baseline, 3725 participants free of end-stage kidney disease (ESKD) were included in the analyses. The association of SAF with incident ESKD or ≥30% reduction in estimated glomerular filtration rate (eGFR) was examined with Cox regression, linear mixed-effects model for the association with annual eGFR decline, and mediation analyses for the mediating roles of renal markers. RESULTS: During a median (IQR) 1.8 (1.1-3.1) years of follow-up, 411 participants developed the outcome. SAF was associated with progression of kidney disease (hazard ratio 1.15 per SD, 95% confidence interval [CI] [1.04, 1.28]) and annual decline in eGFR (ß -0.39 per SD, 95% CI [-0.71, -0.07]) after adjustment for risk factors, including baseline eGFR and urinary albumin-creatinine ratio (UACR). Decreased eGFR (12.9%) and increased UACR (25.8%) accounted for 38.7% of the effect of SAF on renal outcome. CONCLUSIONS: SAF is independently associated with progression of kidney disease. More than half of its effect is independent of renal markers. SAF is of potential to be a prognostic marker for kidney dysfunction.

The relationship of neutrophil elastase and proteinase 3 with risk factors, and chronic complications in type 2 diabetes: A Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) sub-study.

INTRODUCTION: Neutrophil elastase (NE) and proteinase 3 (PR3) are novel inflammation biomarkers. We investigated their associations with chronic complications, determinants of biomarker levels and effects of fenofibrate in patients with type 2 diabetes mellitus (T2DM) from Fenofibrate Intervention and Event Lowering in Diabetes study. METHODS: Plasma NE and PR3 levels were quantified at baseline (n = 2000), and relationships with complications over 5-years assessed. Effects of fenofibrate on biomarker levels (n = 200) were determined at four follow-up visits. RESULTS: Higher waist-to-hip ratio, homocysteine and C-reactive protein and lower apoA-II were determinants of higher NE and PR3 levels. Higher NE levels were associated with on-trial stroke and cardiovascular mortality, and higher PR3 levels with on-trial stroke, but associations were not significant after adjustment for confounding factors. Although higher NE and PR3 levels were associated with baseline total microvascular disease, only NE levels were associated with on-trial neuropathy or amputation. These associations were not significant after adjusting for multiple comparisons. NE and PR3 levels did not change with fenofibrate. CONCLUSIONS: In T2DM plasma NE and PR3 levels are associated with vascular risk factors, and total microvascular disease at baseline, but on rigorous analyses were not associated with on-trial complications. Levels were not changed by fenofibrate.

Investigating the role of dachshund b in the development of the pancreatic islet in zebrafish.

AIMS/INTRODUCTION: ß-Cell dysfunction is a hallmark of type 2 diabetes. In a previous pilot study, we identified an association between genetic variants within the human DACH1 gene and young-onset type 2 diabetes. Here, we characterized the function of dachb, the only dach homologue to be expressed in the pancreas, in developing zebrafish embryos. MATERIALS AND METHODS: We injected one-cell stage embryos with a dachb-morpholino (MO) or with the dachb-MO and dachb messenger ribonucleic acid, and determined the effect on the development of the pancreatic islet. We also carried out quantitative polymerase chain reaction and ribonucleic acid sequencing on the dachb-MO group to determine the effect of dachb knockdown on gene expression. RESULTS: MO-mediated dachb knockdown resulted in impaired islet cell development, with a significant decrease in both the ß-cell and islet cell numbers. This islet developmental defect was rescued when embryos were co-injected with dachb-MO and dachb messenger ribonucleic acid. Knockdown of dachb was associated with a significant downregulation of the ß-cell specific marker gene, insa, and the somatostatin cell marker, sst2, as well as regulators of pancreas development, ptf1a, neuroD, pax6a and nkx6.1, and the cell cycle gene, insm1a. Furthermore, ribonucleic sequencing analysis showed an upregulation of genes enriched in the forkhead box O and mitogen-activated protein kinase signaling pathways in the dachb-MO group, when compared with the control groups. CONCLUSIONS: Together, our results suggest the possible role of dachb in islet development in zebrafish.

Smad3 deficiency promotes beta cell proliferation and function in db/db mice via restoring Pax6 expression.

Rationale: Transforming Growth Factor-beta (TGF-ß) /Smad3 signaling has been shown to play important roles in fibrotic and inflammatory diseases, but its role in beta cell function and type 2 diabetes is unknown. Methods: The role of Smad3 in beta cell function under type 2 diabetes condition was investigated by genetically deleting Smad3 from db/db mice. Phenotypic changes of pancreatic islets and beta cell function were compared between Smad3 knockout db/db (Smad3KO-db/db) mice and Smad3 wild-type db/db (Smad3WT-db/db) mice, and other littermate controls. Islet-specific RNA-sequencing was performed to identify Smad3-dependent differentially expressed genes associated with type 2 diabetes. In vitro beta cell proliferation assay and insulin secretion assay were carried out to validate the mechanism by which Smad3 regulates beta cell proliferation and function. Results: The results showed that Smad3 deficiency completely protected against diabetes-associated beta cell loss and dysfunction in db/db mice. By islet-specific RNA-sequencing, we identified 8160 Smad3-dependent differentially expressed genes associated with type 2 diabetes, where Smad3 deficiency markedly prevented the down-regulation of those genes. Mechanistically, Smad3 deficiency preserved the expression of beta cell development mediator Pax6 in islet, thereby enhancing beta cell proliferation and function in db/db mice in vivo and in Min6 cells in vitro. Conclusions: Taken together, we discovered a pathogenic role of Smad3 in beta cell loss and dysfunction via targeting the protective Pax6. Thus, Smad3 may represent as a novel therapeutic target for type 2 diabetes prevention and treatment.

Long-term maternal cardiometabolic outcomes 22 years after gestational diabetes mellitus.

AIMS/INTRODUCTION: Women with gestational diabetes mellitus are at increased risk for type 2 diabetes. We characterized the association between maternal glycemia during pregnancy with long-term outcomes. METHODS AND METHODS: In this prospective nested case-cohort study, participants were recalled for follow up with detailed evaluation including oral glucose tolerance test at 8, 15 and 22 years. Logistic regression was used to estimate the risk of developing impaired glucose tolerance/type 2 diabetes and metabolic syndrome at follow up. The association between maternal glycemia at pregnancy and follow up was evaluated by linear regression. We also charted trajectory of ß-cell function during follow up. RESULTS: The analysis included 121 women with a mean follow-up period of 22.5 years, and a mean age of 50.3 years. Gestational diabetes was associated with an adjusted odds ratio of 2.48 (95% confidence interval 1.03-5.99) for combined diabetes/impaired glucose tolerance at follow up (P = 0.04). Women with a pre-pregnancy body mass index ≥23 had an odds ratio of 5.43 (95% confidence interval 1.87-15.72) for metabolic syndrome at follow up, compared with those with body mass index <23 (P = 0.002). Both fasting and 2-h glucose during pregnancy were strongly associated with glycemic indices at follow up (P-value <0.001-0.016). Gestational diabetes was associated with impaired ß-cell function that remained relatively stable after the index pregnancy. CONCLUSIONS: Chinese women with a history of gestational diabetes have a high prevalence of impaired glucose tolerance/type 2 diabetes at 22-year follow up. Glucose levels during mid-pregnancy are strongly associated with those of middle age.

Region-based interaction detection in genome-wide case-control studies.

BACKGROUND: In genome-wide association study (GWAS), conventional interaction detection methods such as BOOST are mostly based on SNP-SNP interactions. Although single nucleotides are the building blocks of human genome, single nucleotide polymorphisms (SNPs) are not necessarily the smallest functional unit for complex phenotypes. Region-based strategies have been proved to be successful in studies aiming at marginal effects. METHODS: We propose a novel region-region interaction detection method named RRIntCC (region-region interaction detection for case-control studies). RRIntCC uses the correlations between individual SNP-SNP interactions based on linkage disequilibrium (LD) contrast test. RESULTS: Simulation experiments showed that our method can achieve a higher power than conventional SNP-based methods with similar type-I-error rates. When applied to two real datasets, RRIntCC was able to find several significant regions, while BOOST failed to identify any significant results. The source code and the sample data of RRIntCC are available at http://bioinformatics.ust.hk/RRIntCC.html. CONCLUSION: In this paper, a new region-based interaction detection method with better performance than SNP-based interaction detection methods has been proposed.

Association between educational level and cardiovascular disease and all-cause mortality in patients with type 2 diabetes: a prospective study in the Joint Asia Diabetes Evaluation Program.

PURPOSE: The aim of this study was to describe the association between educational level and incident cardiovascular disease (CVD) and all-cause mortality in Hong Kong Chinese patients with type 2 diabetes. PATIENTS AND METHODS: We included 12,634 patients with type 2 diabetes who were enrolled into the Joint Asia Diabetes Evaluation Program between June 1, 2007, and June 30, 2017. We classified patients' educational level into the following three groups: ≤6 years, 6-13 years, and >13 years. Incident CVD events were identified using hospital discharge diagnoses. Death was identified from Hong Kong Death Register. We estimated HRs for incident CVD and all-cause mortality using Cox regression models. RESULTS: Patients with the highest educational level were younger and had shorter diabetes duration and better glycemic control at enrollment than those with the lowest educational level. During the median follow-up of 6.2 years for CVD and 6.4 years for all-cause mortality, 954 CVD events and 833 deaths were recorded. HRs for CVD and all-cause mortality were 0.73 (95% CI: 0.57, 0.94) and 0.71 (95% CI: 0.54, 0.94) for the highest educational level compared to the lowest educational level, after adjustment for age, sex, diabetes duration, and family history of diabetes. CONCLUSION: Educational level is inversely associated with the risk of CVD and all-cause mortality among Hong Kong Chinese patients with type 2 diabetes. Hong Kong Chinese patients with type 2 diabetes and low educational level should be given special attention for the prevention of key complications of diabetes.

Precision medicine in diabetes prevention, classification and management.

Diabetes has become a major burden of healthcare expenditure. Diabetes management following a uniform treatment algorithm is often associated with progressive treatment failure and development of diabetic complications. Recent advances in our understanding of the genomic architecture of diabetes and its complications have provided the framework for development of precision medicine to personalize diabetes prevention and management. In the present review, we summarized recent advances in the understanding of the genetic basis of diabetes and its complications. From a clinician's perspective, we attempted to provide a balanced perspective on the utility of genomic medicine in the field of diabetes. Using genetic information to guide management of monogenic forms of diabetes represents the best-known examples of genomic medicine for diabetes. Although major strides have been made in genetic research for diabetes, its complications and pharmacogenetics, ongoing efforts are required to translate these findings into practice by incorporating genetic information into a risk prediction model for prioritization of treatment strategies, as well as using multi-omic analyses to discover novel drug targets with companion diagnostics. Further research is also required to ensure the appropriate use of this information to empower individuals and healthcare professionals to make personalized decisions for achieving the optimal outcome.

Oral glucose lowering with linagliptin and metformin compared with linagliptin alone as initial treatment in Asian patients with newly diagnosed type 2 diabetes and marked hyperglycemia: Subgroup analysis of a randomized clinical trial.

AIMS/INTRODUCTION: Type 2 diabetes mellitus is an epidemic in Asia, yet clinical trials of glucose-lowering therapies often enroll predominantly Western populations. We explored the initial combination of metformin and linagliptin, a dipeptidyl peptidase-4 inhibitor, in newly diagnosed type 2 diabetes mellitus patients in Asia with marked hyperglycemia. MATERIALS AND METHODS: This was a post-hoc subgroup analysis of a multinational, parallel-group clinical trial in which 316 newly diagnosed type 2 diabetes mellitus patients with glycated hemoglobin A1c (HbA1c) 8.5-12.0% were randomized to double-blind oral treatment with linagliptin/metformin or linagliptin monotherapy. The primary end-point was the change from baseline in HbA1c at week 24. We evaluated data for the 125 participants from Asian countries. RESULTS: After 24 weeks, the mean ± standard error reduction from baseline in HbA1c (mean 10.0%) was -2.99 ± 0.18% with linagliptin/metformin and -1.84 ± 0.18% with linagliptin; a treatment difference of -1.15% (95% confidence interval -1.65 to -0.66, P < 0.0001). HbA1c <7.0% was achieved by 60% of participants receiving linagliptin/metformin. The mean bodyweight change after 24 weeks was -0.45 ± 0.41 kg and 1.33 ± 0.45 kg in the linagliptin/metformin and linagliptin groups, respectively (treatment difference -1.78 kg [95% confidence interval -2.99 to -0.57, P = 0.0043]). Drug-related adverse events occurred in 9.7% of participants receiving linagliptin/metformin and 4.8% of those receiving linagliptin. Hypoglycemia occurred in 6.5% and 4.8% of the linagliptin/metformin and linagliptin groups, respectively, with no severe episodes. Gastrointestinal disorders occurred in 12.9% and 12.7% of the linagliptin/metformin and linagliptin groups, respectively, with no associated treatment discontinuations. CONCLUSIONS: In people from Asia with newly diagnosed type 2 diabetes mellitus and marked hyperglycemia, the initial combination of linagliptin and metformin substantially improved glycemic control without weight gain and with infrequent hypoglycemia. Initial oral combination therapy might be a viable treatment for such individuals.

Plasma Levels of Alanine Aminotransferase in the First Trimester Identify High Risk Chinese Women for Gestational Diabetes.

Alanine aminotransferase (ALT) predicts type 2 diabetes but it is uncertain whether it also predicts gestational diabetes mellitus (GDM). We recruited 17359 Chinese women with ALT measured in their first trimester. At 24-28 weeks of gestation, all women underwent a 50-gram 1-hour glucose challenge test (GCT) followed by a 75-gram 2-hour oral glucose tolerance test if GCT result was ≥7.8 mmol/L. Restricted cubic spline analysis was used to examine full-range risk associations of ALT levels with GDM. Relative excess risk due to interaction, attributable proportion due to interaction and synergy index were used to estimate additive interaction between high ALT and overweight/obesity for GDM. Finally, 1332 (7.7%) women had GDM. ALT levels were positively associated with GDM risk without a clear threshold. Using ALT levels <22 U/L as the referent, the middle ALT levels (≥22 to <40 U/L) [odds ratio (OR) (95% confidence intervals): 1.41(1.21-1.65)] and high ALT levels (≥40 U/L) [1.62 (1.31-2.00)] were associated with increased GDM risk. Maternal overweight/obesity greatly enhanced the OR of ALT ≥22 U/L from 1.44 (1.23-1.69) to 3.46 (2.79-4.29) with significant additive interactions. In conclusion, elevated ALT levels in the first trimester even within normal range predicted GDM risk, further enhanced by overweight/obesity.

Whole-genome bisulfite sequencing of multiple individuals reveals complementary roles of promoter and gene body methylation in transcriptional regulation.

BACKGROUND: DNA methylation is an important type of epigenetic modification involved in gene regulation. Although strong DNA methylation at promoters is widely recognized to be associated with transcriptional repression, many aspects of DNA methylation remain not fully understood, including the quantitative relationships between DNA methylation and expression levels, and the individual roles of promoter and gene body methylation. RESULTS: Here we present an integrated analysis of whole-genome bisulfite sequencing and RNA sequencing data from human samples and cell lines. We find that while promoter methylation inversely correlates with gene expression as generally observed, the repressive effect is clear only on genes with a very high DNA methylation level. By means of statistical modeling, we find that DNA methylation is indicative of the expression class of a gene in general, but gene body methylation is a better indicator than promoter methylation. These findings are general in that a model constructed from a sample or cell line could accurately fit the unseen data from another. We further find that promoter and gene body methylation have minimal redundancy, and either one is sufficient to signify low expression. Finally, we obtain increased modeling power by integrating histone modification data with the DNA methylation data, showing that neither type of information fully subsumes the other. CONCLUSION: Our results suggest that DNA methylation outside promoters also plays critical roles in gene regulation. Future studies on gene regulatory mechanisms and disease-associated differential methylation should pay more attention to DNA methylation at gene bodies and other non-promoter regions.

Validation of methods to control for immortal time bias in a pharmacoepidemiologic analysis of renin-angiotensin system inhibitors in type 2 diabetes.

BACKGROUND: Pharmacoepidemiologic analysis can confirm whether drug efficacy in a randomized controlled trial (RCT) translates to effectiveness in real settings. We examined methods used to control for immortal time bias in an analysis of renin-angiotensin system (RAS) inhibitors as the reference cardioprotective drug. METHODS: We analyzed data from 3928 patients with type 2 diabetes who were recruited into the Hong Kong Diabetes Registry between 1996 and 2005 and followed up to July 30, 2005. Different Cox models were used to obtain hazard ratios (HRs) for cardiovascular disease (CVD) associated with RAS inhibitors. These HRs were then compared to the HR of 0.92 reported in a recent meta-analysis of RCTs. RESULTS: During a median follow-up period of 5.45 years, 7.23% (n = 284) patients developed CVD and 38.7% (n = 1519) were started on RAS inhibitors, with 39.1% of immortal time among the users. In multivariable analysis, time-dependent drug-exposure Cox models and Cox models that moved immortal time from users to nonusers both severely inflated the HR, and time-fixed models that included immortal time deflated the HR. Use of time-fixed Cox models that excluded immortal time resulted in a HR of only 0.89 (95% CI, 0.68-1.17) for CVD associated with RAS inhibitors, which is closer to the values reported in RCTs. CONCLUSIONS: In pharmacoepidemiologic analysis, time-dependent drug exposure models and models that move immortal time from users to nonusers may introduce substantial bias in investigations of the effects of RAS inhibitors on CVD in type 2 diabetes.