The prevalence of type 2 diabetes has increased in both young and old people. We examined age-specific associations and population attributable fractions (PAFs) of risk factors for all-cause and ...cause-specific mortality in people with type 2 diabetes.
We analysed data from 360,202 Chinese with type 2 diabetes who participated in a territory-wide diabetes complication screening programme in Hong Kong between January 2000 and December 2019. We compared the hazard ratios and PAFs of eight risk factors, including three major comorbidities (cardiovascular disease CVD, chronic kidney disease CKD, all-site cancer) and five modifiable risk factors (suboptimal HbA1c, suboptimal blood pressure, suboptimal low-density lipoprotein cholesterol, smoking, and suboptimal weight), for mortality across four age groups (18 to 54, 55 to 64, 65 to 74, and ≥75 years). During a median 6.0 years of follow-up, 44,396 people died, with cancer, CVD, and pneumonia being the leading causes of death. Despite a higher absolute mortality risk in older people (crude all-cause mortality rate: 59.7 versus 596.2 per 10,000 person-years in people aged 18 to 54 years versus those aged ≥75 years), the relative risk of all-cause and cause-specific mortality associated with most risk factors was higher in younger than older people, after mutually adjusting for the eight risk factors and other potential confounders including sex, diabetes duration, lipid profile, and medication use. The eight risk factors explained a larger proportion of mortality events in the youngest (PAF: 51.6%, 95% confidence interval CI 39.1%, 64.0%, p < 0.001) than the oldest (PAF: 35.3%, 95% CI 27.2%, 43.4%, p < 0.001) age group. Suboptimal blood pressure (PAF: 16.9%, 95% CI 14.7%, 19.1%, p < 0.001) was the leading attributable risk factor for all-cause mortality in the youngest age group, while CKD (PAF: 15.2%, 95% CI 14.0%, 16.4%, p < 0.001) and CVD (PAF: 9.2%, 95% CI 8.3%, 10.1%, p < 0.001) were the leading attributable risk factors in the oldest age group. The analysis was restricted to Chinese, which might affect the generalisability to the global population with differences in risk profiles. Furthermore, PAFs were estimated under the assumption of a causal relationship between risk factors and mortality. However, reliable causality was difficult to establish in the observational study.
Major comorbidities and modifiable risk factors were associated with a greater relative risk for mortality in younger than older people with type 2 diabetes and their associations with population mortality burden varied substantially by age. These findings highlight the importance of early control of blood pressure, which could reduce premature mortality in young people with type 2 diabetes and prevent the onset of later CKD and related mortality at older ages.
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
Little is known about the lifetime risk of progression to diabetes in the Asian population. We determined remaining lifetime risk of diabetes and life years spent with diabetes in Chinese people with ...normoglycemia and prediabetes. Using territory-wide diabetes surveillance data curated from electronic medical records of Hong Kong Hospital Authority (HA), we conducted a population-based cohort study in 2,608,973 individuals followed from 2001 to 2019. Prediabetes and diabetes were identified based on laboratory measurements, diagnostic codes, and medication records. Remaining lifetime risk and life years spent with diabetes were estimated using Monte Carlo simulations with state transition probabilities based on a Markov chain model. Validations were performed using several sensitivity analyses and modified survival analysis. External replication was performed using the China Health and Retirement Longitudinal Survey (CHARLS) cohort (2010 to 2015). These findings suggest that Hong Kong, an economically developed city in Asia, is confronted with huge challenge of high lifetime risk of diabetes and long life years spent with diabetes, especially in people with prediabetes. Effective public health policies and targeted interventions for preventing progression to diabetes are urgently needed.
Type 2 diabetes affects multiple systems. We aimed to compare age- and sex-specific rates of all-cause and cause-specific hospital bed-days between people with and without type 2 diabetes.
Data were ...provided by the Hong Kong Hospital Authority. We included 1,516,508 one-to-one matched people with incident type 2 diabetes (n = 758,254) and those without diabetes during the entire follow-up period (n = 758,254) between 2002 and 2018, followed until 2019. People with type 2 diabetes and controls were matched for age at index date (±2 years), sex, and index year (±2 years). We defined hospital bed-day rate as total inpatient bed-days divided by follow-up time. We constructed negative binominal regression models to estimate hospital bed-day rate ratios (RRs) by age at diabetes diagnosis and sex. All RRs were stratified by sex and adjusted for age and index year. During a median of 7.8 years of follow-up, 60.5% (n = 459,440) of people with type 2 diabetes and 56.5% (n = 428,296) of controls had a hospital admission for any cause, with a hospital bed-day rate of 3,359 bed-days and 2,350 bed-days per 1,000 person-years, respectively. All-cause hospital bed-day rate increased with increasing age in controls, but showed a J-shaped relationship with age in people with type 2 diabetes, with 38.4% of bed-days in those diagnosed <40 years caused by mental health disorders. Type 2 diabetes was associated with increased risks for a wide range of medical conditions, with an RR of 1.75 (95% CI confidence interval 1.73, 1.76; p < 0.001) for all-cause hospital bed-days in men and 1.87 (95% CI 1.85, 1.89; p < 0.001) in women. The RRs were greater in people with diabetes diagnosed at a younger than older age and varied by sex according to medical conditions. Sex differences were most notable for a higher RR for urinary tract infection and peptic ulcer, and a lower RR for chronic kidney disease and pancreatic disease in women than men. The main limitation of the study was that young people without diabetes in the database were unlikely to be representative of those in the Hong Kong general population with potential selection bias due to inclusion of individuals in need of medical care.
In this study, we observed that type 2 diabetes was associated with increased risks of hospital bed-days for a wide range of medical conditions, with an excess burden of mental health disorders in people diagnosed at a young age. Age and sex differences should be considered in planning preventive and therapeutic strategies for type 2 diabetes. Effective control of risk factors with a focus on mental health disorders are urgently needed in young people with type 2 diabetes. Healthcare systems and policymakers should consider allocating adequate resources and developing strategies to meet the mental health needs of young people with type 2 diabetes, including integrating mental health services into diabetes care.
Aims/hypothesis
The aim of the study was to describe trends in all-cause and cause-specific mortality rates in Hong Kong Chinese people with diabetes from 2001 to 2016.
Methods
The Hong Kong Diabetes ...Surveillance Database (HKDSD) is a territory-wide diabetes cohort identified from the Hong Kong Hospital Authority electronic medical record system. Deaths between 2001 and 2016 were identified from linkage to the Hong Kong Death Registry. We used Joinpoint regression analysis to describe mortality patterns among people with diabetes by age and sex, and standardised mortality ratios (SMRs) to compare all-cause mortality rates in people with and without diabetes.
Results
Between 2001 and 2016, a total of 390,071 men and 380,007 women aged 20 years or older with diabetes were included in the HKDSD. There were 96,645 deaths among men and 88,437 deaths among women. Mortality rates for all-cause, cardiovascular disease and cancer among people with diabetes declined by 52.3%, 72.2% and 65.1% in men, respectively, and by 53.5%, 78.5% and 59.6% in women, respectively. Pneumonia mortality rates remained stable. The leading cause of death in people with diabetes has shifted from cardiovascular disease to pneumonia in the oldest age group, with cancer remaining the most common cause of death in people aged 45–74 years. The all-cause SMRs for men declined from 2.82 (95% CI 2.72, 2.94) to 1.50 (95% CI 1.46, 1.54), and for women, they declined from 3.28 (95% CI 3.15, 3.41) to 1.67 (95% CI 1.62, 1.72). However, among people aged 20–44 years, the declines in all-cause mortality rates over the study period were not statistically significant for both men (average annual per cent change AAPC: −3.2% 95% CI −7.3%, 1.0%) and women (AAPC: −1.2% 95% CI −6.5%, 4.4%). The SMRs in people aged 20−44 years fluctuated over time, between 7.86 (95% CI 5.74, 10.5) in men and 6.10 (95% CI 3.68, 9.45) in women in 2001, and 4.95 (95% CI 3.72, 6.45) in men and 4.92 (95% CI 3.25, 7.12) in women in 2016.
Conclusions/interpretation
Absolute and relative mortality has declined overall in people with diabetes in Hong Kong, with less marked improvements in people under 45 years of age, calling for urgent action to improve care in young people with diabetes.
There is very limited data on the time trend of diabetes incidence in Asia. Using population-level data, we report the secular trend of the incidence of type 1 and type 2 diabetes in Hong Kong ...between 2002 and 2015.
The Hong Kong Diabetes Surveillance Database hosts clinical information on people with diabetes receiving care under the Hong Kong Hospital Authority, a statutory body that governs all public hospitals and clinics. Sex-specific incidence rates were standardised to the age structure of the World Health Organization population. Joinpoint regression analysis was used to describe incidence trends. A total of 562,022 cases of incident diabetes (type 1 diabetes n = 2,426: mean age at diagnosis is 32.5 years, 48.4% men; type 2 diabetes n = 559,596: mean age at diagnosis is 61.8 years, 51.9% men) were included. Among people aged <20 years, incidence of both type 1 and type 2 diabetes increased. For type 1 diabetes, the incidence increased from 3.5 (95% CI 2.2-4.9) to 5.3 (95% CI 3.4-7.1) per 100,000 person-years (average annual percentage change AAPC 3.6% 95% CI 0.2-7.1, p < 0.05) in boys and from 4.3 (95% CI 2.7-5.8) to 6.4 (95% CI 4.3-8.4) per 100,000 person-years (AAPC 4.7% 95% CI 1.7-7.7, p < 0.05 in girls; for type 2 diabetes, the incidence increased from 4.6 (95% CI 3.2-6.0) to 7.5 (95% CI 5.5-9.6) per 100,000 person-years (AAPC 5.9% 95% CI 3.4-8.5, p < 0.05) in boys and from 5.9 (95% CI 4.3-7.6) to 8.5 (95% CI 6.2-10.8) per 100,000 person-years (AAPC 4.8% 95% CI 2.7-7.0, p < 0.05) in girls. In people aged 20 to <40 years, incidence of type 1 diabetes remained stable, but incidence of type 2 diabetes increased over time from 75.4 (95% CI 70.1-80.7) to 110.8 (95% CI 104.1-117.5) per 100,000 person-years (AAPC 4.2% 95% CI 3.1-5.3, p < 0.05) in men and from 45.0 (95% CI 41.4-48.6) to 62.1 (95% CI 57.8-66.3) per 100,000 person-years (AAPC 3.3% 95% CI 2.3-4.2, p < 0.05) in women. In people aged 40 to <60 years, incidence of type 2 diabetes increased until 2011/2012 and then flattened. In people aged ≥60 years, incidence was stable in men and declined in women after 2011. No trend was identified in the incidence of type 1 diabetes in people aged ≥20 years. The present study is limited by its reliance on electronic medical records for identification of people with diabetes, which may result in incomplete capture of diabetes cases. The differentiation of type 1 and type 2 diabetes was based on an algorithm subject to potential misclassification.
There was an increase in incidence of type 2 diabetes in people aged <40 years and stabilisation in people aged ≥40 years. Incidence of type 1 diabetes continued to climb in people aged <20 years but remained constant in other age groups.
Diabetes outcomes are influenced by host factors, settings, and care processes. We examined the association of data-driven integrated care assisted by information and communications technology (ICT) ...with clinical outcomes in type 2 diabetes in public and private healthcare settings.
The web-based Joint Asia Diabetes Evaluation (JADE) platform provides a protocol to guide data collection for issuing a personalized JADE report including risk categories (1-4, low-high), 5-year probabilities of cardiovascular-renal events, and trends and targets of 4 risk factors with tailored decision support. The JADE program is a prospective cohort study implemented in a naturalistic environment where patients underwent nurse-led structured evaluation (blood/urine/eye/feet) in public and private outpatient clinics and diabetes centers in Hong Kong. We retrospectively analyzed the data of 16,624 Han Chinese patients with type 2 diabetes who were enrolled in 2007-2015. In the public setting, the non-JADE group (n = 3,587) underwent structured evaluation for risk factors and complications only, while the JADE (n = 9,601) group received a JADE report with group empowerment by nurses. In a community-based, nurse-led, university-affiliated diabetes center (UDC), the JADE-Personalized (JADE-P) group (n = 3,436) received a JADE report, personalized empowerment, and annual telephone reminder for reevaluation and engagement. The primary composite outcome was time to the first occurrence of cardiovascular-renal diseases, all-site cancer, and/or death, based on hospitalization data censored on 30 June 2017. During 94,311 person-years of follow-up in 2007-2017, 7,779 primary events occurred. Compared with the JADE group (136.22 cases per 1,000 patient-years 95% CI 132.35-140.18), the non-JADE group had higher (145.32 95% CI 138.68-152.20; P = 0.020) while the JADE-P group had lower event rates (70.94 95% CI 67.12-74.91; P < 0.001). The adjusted hazard ratios (aHRs) for the primary composite outcome were 1.22 (95% CI 1.15-1.30) and 0.70 (95% CI 0.66-0.75), respectively, independent of risk profiles, education levels, drug usage, self-care, and comorbidities at baseline. We reported consistent results in propensity-score-matched analyses and after accounting for loss to follow-up. Potential limitations include its nonrandomized design that precludes causal inference, residual confounding, and participation bias.
ICT-assisted integrated care was associated with a reduction in clinical events, including death in type 2 diabetes in public and private healthcare settings.