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.

Changing landscape of diabetes in Asia - What are the unmet needs?

The incidence rates of type 2 diabetes among adults in Asia have been stable, but the rates in youth and young adults have increased. In territory-wide surveillance in Hong Kong, Special Administrative Region of People's Republic of China, all-cause mortality rates among people with diabetes have exhibited a declining trend in the past 15 years, with a narrowing in the mortality gap between people with and without diabetes. At the same time, the improvement in survival resulted in a changing age structure and disease profile of people with diabetes, towards an increasing proportion of older people with long diabetes duration and multi-morbidities. Reductions in event rates were not observed in the youngest age group who also had the least gains in risk factor control and uptake in organ protective drugs over time. A young age at diabetes diagnosis, associated with exposure to high glycemic burden from an early age, predicted higher risks of complications and premature mortality compared with later-onset of diabetes. People presenting with type 2 diabetes below 40 years of age were 5-fold more likely to die and their life expectancy was shortened by 8 years than age-matched counterparts without diabetes. Analysis of population-based data in Hong Kong Chinese identified hypertension followed by chronic kidney disease as the leading contributor to mortality in young people, indicating that efforts to optimize non-glycemic risk factors and organ protection are as important in young individuals as it is in the older population.

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.

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.

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.

Impact of age at type 2 diabetes mellitus diagnosis on mortality and vascular complications: systematic review and meta-analyses.

AIMS/HYPOTHESIS: Few studies examine the association between age at diagnosis and subsequent complications from type 2 diabetes. This paper aims to summarise the risk of mortality, macrovascular complications and microvascular complications associated with age at diagnosis of type 2 diabetes. METHODS: Data were sourced from MEDLINE and All EBM (Evidence Based Medicine) databases from inception to July 2018. Observational studies, investigating the effect of age at diabetes diagnosis on macrovascular and microvascular diabetes complications in adults with type 2 diabetes were selected according to pre-specified criteria. Two investigators independently extracted data and evaluated all studies. If data were not reported in a comparable format, data were obtained from authors, presented as minimally adjusted ORs (and 95% CIs) per 1 year increase in age at diabetes diagnosis, adjusted for current age for each outcome of interest. The study protocol was recorded with PROSPERO International Prospective Register of Systematic Reviews (CRD42016043593). RESULTS: Data from 26 observational studies comprising 1,325,493 individuals from 30 countries were included. Random-effects meta-analyses with inverse variance weighting were used to obtain the pooled ORs. Age at diabetes diagnosis was inversely associated with risk of all-cause mortality and macrovascular and microvascular disease (all p < 0.001). Each 1 year increase in age at diabetes diagnosis was associated with a 4%, 3% and 5% decreased risk of all-cause mortality, macrovascular disease and microvascular disease, respectively, adjusted for current age. The effects were consistent for the individual components of the composite outcomes (all p < 0.001). CONCLUSIONS/INTERPRETATION: Younger, rather than older, age at diabetes diagnosis was associated with higher risk of mortality and vascular disease. Early and sustained interventions to delay type 2 diabetes onset and improve blood glucose levels and cardiovascular risk profiles of those already diagnosed are essential to reduce morbidity and mortality. Graphical abstract.

Depression in Chinese patients with type 2 diabetes: associations with hyperglycemia, hypoglycemia, and poor treatment adherence.

BACKGROUND: We hypothesize that depression in type 2 diabetes might be associated with poor glycemic control, in part due to suboptimal self-care. We tested this hypothesis by examining the associations of depression with clinical and laboratory findings in a multicenter survey of Chinese type 2 diabetic patients. METHOD: 2538 patients aged 18-75 years attending hospital-based clinics in four cities in China underwent detailed clinical-psychological-behavioral assessment during a 12-month period between 2011 and 2012. Depression was diagnosed if Patient Health Questionnaire-9 (PHQ-9) score ≥10. Diabetes self-care and medication adherence were assessed using the Summary of Diabetes Self-care Activities and the 4-item Morisky medication adherence scale respectively. RESULTS: In this cross-sectional study (mean age: 56.4 ± 10.5[SD] years, 53% men), 6.1% (n = 155) had depression. After controlling for study sites, patients with depression had higher HbA(1c) (7.9 ± 2.0 vs. 7.7 ± 2.0%, P = 0.008) and were less likely to achieve HbA(1c) goal of <7.0% (36.2% vs 45.6%, P = 0.004) than those without depression. They were more likely to report hypoglycemia and to have fewer days of being adherent to their recommended diet, exercise, foot care and medication. In logistic regression, apart from young age, poor education, long disease duration, tobacco use, high body mass index, use of insulin, depression was independently associated with failure to attain HbA(1c) target (Odds Ratio [OR] = 1.56, 95%CI:1.05-2.32, P = 0.028). The association between depression and glycemic control became non-significant after inclusion of adherence to diet, exercise and medication (OR = 1.48, 95% CI 0.99-2.21, P = 0.058). CONCLUSION: Depression in type 2 diabetes was closely associated with hyperglycemia and hypoglycemia, which might be partly mediated through poor treatment adherence.

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.