Cancer risk following onset of type 2 diabetes in New Zealanders with impaired glucose tolerance over 25 years: a matched prospective cohort study.

BACKGROUND: In people with prediabetes, the link between developing type 2 diabetes (T2D) and cancer risk among those with impaired glucose tolerance (IGT) remains uncertain. We examined this association in IGT individuals from primary care in South and West Auckland, New Zealand, spanning 1994-2019, assessing 5- and 10-year cancer risks. METHODS: Study cohorts were extracted from the Diabetes Care Support Service in Auckland, New Zealand, linking it with national registries for death, cancer, hospital admissions, pharmaceutical claims, and socioeconomic status. We compared cancer risks in individuals with IGT newly diagnosed with or without T2D within a 1-5-year exposure window. Employing tapered matching and landmark analysis to address potential confounding effects, we formed comparative IGT cohorts. Weighted Cox regression models were then employed to assess the association between T2D onset and 5- and 10-year cancer risks. RESULTS: The study included 26,794 patients with IGT, with 629 newly diagnosed with T2D within 5 years and 13,007 without such a diagnosis. Those progressing to T2D had similar 5-year cancer risk but significantly higher 10-year risk (HR 1.35; 95% CI 1.09-1.68). This association was stronger in older individuals, the socioeconomically deprived, current smokers, those with worse metabolic measures, and lower renal function. Patients with IGT of NZ European ethnicity had lower 10-year cancer risk. CONCLUSIONS: T2D diagnosis influences cancer risk in individuals with IGT. Developing risk scores for high-risk IGT individuals and implementing cancer screening and structured diabetes prevention, especially in deprived or minority ethnic populations, is essential.

Long-term impact of type 2 diabetes onset on dementia incidence rate among New Zealanders with impaired glucose tolerance: A tapered-matched landmark analysis over 25 years.

INTRODUCTION: We aimed to investigate the association between the onset of type 2 diabetes (T2D) and dementia incidence rates (IR) in the population with impaired glucose tolerance (IGT) identified in primary care in New Zealand (NZ) over 25 years. METHODS: Tapered matching and landmark analysis (accounting for immortal bias) were used to control for potential effects of known confounders. The association between T2D onset and 5- and 10-year IR of dementia was estimated by weighted Cox models. RESULTS: The onset of T2D was significantly associated with the 10-year IR of dementia, especially in the socioeconomically deprived, those of non-NZ European ethnicity, those currently smoking, and patients with higher metabolic measures. DISCUSSION: Our findings suggest that the onset of T2D is a significant risk factor for dementia in individuals with IGT. Dementia screening and structured diabetes prevention are vital in the population with IGT, particularly those from deprived or ethnic minority backgrounds. HIGHLIGHTS: Increased dementia incidence rate links with T2D onset in people with IGT. Significant incidence varied by ethnicity, socioeconomic status, and health factors. Results emphasize the diabetes manage and socioeconomic factors on dementia risk. Secondary analysis highlights the key role of vascular health in dementia prevention.

Uncovering Structural Plasticity of Enterovirus A through Deep Insertional and Deletional Scanning.

Insertions and deletions (InDels) are essential sources of novelty in protein evolution. In RNA viruses, InDels cause dramatic phenotypic changes contributing to the emergence of viruses with altered immune profiles and host engagement. This work aimed to expand our current understanding of viral evolution and explore the mutational tolerance of RNA viruses to InDels, focusing on Enterovirus A71 (EV-A71) as a prototype for Enterovirus A species (EV-A). Using newly described deep InDel scanning approaches, we engineered approximately 45,000 insertions and 6,000 deletions at every site across the viral proteome, quantifying their effects on viral fitness. As a general trend, most InDels were lethal to the virus. However, our screen reproducibly identified a set of InDel-tolerant regions, demonstrating our ability to comprehensively map tolerance to these mutations. Tolerant sites highlighted structurally flexible and mutationally plastic regions of viral proteins that avoid core structural and functional elements. Phylogenetic analysis on EV-A species infecting diverse mammalian hosts revealed that the experimentally-identified hotspots overlapped with sites of InDels across the EV-A species, suggesting structural plasticity at these sites is an important function for InDels in EV speciation. Our work reveals the fitness effects of InDels across EV-A71, identifying regions of evolutionary capacity that require further monitoring, which could guide the development of Enterovirus vaccines.

All-cause, premature, and cardiovascular death attributable to socioeconomic and ethnic disparities among New Zealanders with type 1 diabetes 1994-2019: a multi-linked population-based cohort study.

BACKGROUND: New Zealand (NZ) research into type 1 diabetes mellitus (T1DM) mortality can inform policy and future research. In this study we aimed to quantify the magnitude to which ethnicity and socioeconomic disparities influenced mortality at the population level among people with Type 1 diabetes (T1DM) in Auckland, New Zealand (NZ). METHODS: The cohort data were derived from the primary care diabetes audit program the Diabetes Care Support Service (DCSS), and linked with national primary care, pharmaceutical claims, hospitalisation, and death registration databases. People with T1DM enrolled in DCSS between 1994-2018 were included. All-cause, premature, and cardiovascular mortalities were estimated by Poisson regression models with adjustment for population-level confounders. The mortality rates ratio (MRR) was standardized against the DCSS type 2 diabetes population. Mortality rates were compared by ethnic group (NZ European (NZE) and non-NZE) and socioeconomic deprivation quintile. The population attributable fraction (PAF) was estimated for ethnic and socioeconomic disparities by Cox regression adjusting for demographic, lifestyle, and clinical covariates. The adjusted slope index inequality (SII) and relative index of inequality (RII) were used to measure the socioeconomic disparity in mortalities. RESULTS: Overall, 2395 people with T1DM (median age 34.6 years; 45% female; 69% NZE) were enrolled, among whom the all-cause, premature and CVD mortalities were 6.69 (95% confidence interval: 5.93-7.53), 3.30 (2.77-3.90) and 1.77 (1.39-2.23) per 1,000 person-years over 25 years. The overall MRR was 0.39 (0.34-0.45), 0.65 (0.52-0.80), and 0.31 (0.24-0.41) for all-cause, premature and CVD mortality, respectively. PAF attributable to ethnicity disparity was not significantly different for mortality. The adjusted PAF indicated that 25.74 (0.84-44.39)% of all-cause mortality, 25.88 (0.69-44.69)% of premature mortality, 55.89 (1.20-80.31)% of CVD mortality could be attributed to socioeconomic inequality. The SII was 8.04 (6.30-9.78), 4.81 (3.60-6.02), 2.70 (1.82-3.59) per 1,000 person-years and RII was 2.20 (1.94-2.46), 2.46 (2.09-2.82), and 2.53 (2.03-3.03) for all-cause, premature and CVD mortality, respectively. CONCLUSIONS: Our results suggest that socioeconomic disparities were responsible for a substantial proportion of all-cause, premature and CVD mortality in people with T1DM in Auckland, NZ. Reducing socioeconomic barriers to management and self-management would likely improve clinical outcomes.

Health Inequality in Eight Adverse Outcomes Over a 25-Year Period in a Multi-Ethnic Population in New Zealand Population with Impaired Glucose Tolerance and/or Impaired Fasting Glucose: An Age-Period-Cohort Analysis.

Purpose: We aimed to examine socioeconomic inequality (SI) in cause-specific outcomes among adults with impaired glucose tolerance (IGT) and/or Impaired fasting glucose (IFG) in New Zealand (NZ) over 25 years. Patients and Methods: A population-based open cohort was derived from Diabetes Care Support Service in NZ with national databases linkage. Patients aged ≥18 years with IGT and/or IFG were enrolled between 01/01/1994 and 31/07/2018 and followed up until death or 31/12/2018. Incident outcomes (all-cause, premature, cardiovascular, and cancer death; cardiovascular, myocardial infarction, stroke, heart failure, and end-stage kidney disease hospitalization) by demographic, anthropometric, socioeconomic status, clinical measurements, enrol-time-periods, and IGT/IFG were evaluated. Adjusted incidence rate ratios, absolute risk difference, and SI measurements (slope and relative index of inequality) were estimated using Age-Period-Cohort models. Results: 29,894 patients (58.5 (SD 14.3) years mean age; 52.2% female) were enrolled with 5.6 (IQR: 4.4-7.4) years of median follow-up. Mortality rates decreased, whereas hospitalization (except myocardial infarction) rates increased. SI was significant for each outcome. Higher mortality and hospitalization rates and worsened SI were common in men, older, the most deprived, and Maori patients, as well as patients with obesity, current smoking, with both IFG and IGT, and greater metabolic derangement (higher systolic blood pressure, lipids, and HbA1c, and lower level of mean arterial pressure). Conclusion: Enhanced management strategies are necessary for people with IGT and/or IFG to address persisting SI, especially for men, older people, current smokers, NZ European and Maori patients, patients with obesity, or with any abnormal metabolic measurements.

Association Between Onset of Type 2 Diabetes and Risk of Atrial Fibrillation in New Zealanders With Impaired Glucose Tolerance Over 25 Years.

Background The association between the onset of type 2 diabetes (T2D) and atrial fibrillation (AF) risk in individuals with impaired glucose tolerance (IGT) remains unclear. This study aimed to investigate the relationship between the incident onset of T2D and 5- and 10-year (after the landmark period) risks of AF in people with IGT identified in South and West Auckland primary care settings between 1994 and 2019. Methods and Results We compared AF risk in patients with IGT with and without newly diagnosed T2D within a 1- to 5-year exposure window. Tapered matching and landmark analysis (to address immortal bias) were used to control for confounding variables. The cohorts incorporated 785 patients who had T2D newly diagnosed within 5 years from enrollment (landmark date) and 15 079 patients without a T2D diagnosis. Patients progressing to T2D exhibited significantly higher 5-year (after the landmark period) AF risk (hazard ratio [HR], 1.34 [95% CI, 1.10-1.63]) and 10-year (after the landmark period) AF risk (HR, 1.28 [95% CI, 1.02-1.62]) compared with those without incident T2D. The association was more pronounced among men, older patients, socioeconomically deprived individuals, current smokers, those with higher metabolic measures, and lower renal function. New Zealand European ethnicity was associated with a lower 5- and 10-year risk of AF. Conclusions This study found a mediating effect of T2D on the risk of AF in a population with IGT in New Zealand. The development of risk scores and future replication studies can help identify and guide management of individuals with IGT at the highest risk of AF following incident T2D.

Effect of onset of type 2 diabetes on risks of cardiovascular disease and heart failure among new Zealanders with impaired glucose tolerance over 25 years: tapered-matched landmark analysis.

BACKGROUND: This study aimed to examine the association between the incident onset of T2DM and 5- and 10-year risks of CVD and HF in people with IGT identified in primary care in South and West Auckland, New Zealand (NZ) between 1994 and 2019. METHODS: We compared CVD and HF risks in patients with IGT and with/without T2D newly diagnosed within the exposure window (1-5 years). Tapered matching and landmark analysis (to account for immortal bias) were used to control for potential effects of known confounders. RESULTS: Among 26,794 patients enrolled with IGT, 845 had T2D newly diagnosed within 5 years from enrolment (landmark date) and 15,452 did not have T2D diagnosed. Patients progressing to T2D (vs. those not progressing) had a similar 5-year risk for CVD (hazard ratio 1.19; 95% CI 0.61-2.32) but significantly higher 10-year risk of CVD (2.45(1.40-4.29)), 5-year risk of HF (1.94(1.20-3.12)) and 10-year risk of HF (2.84(1.83-4.39). The association between the onset of T2D and risk of 10-year risk of CVD, 5-year and 10-year risk of HF was more likely among men, the socioeconomically deprived, those currently smoking, patients with higher metabolic measures and/or those with lower renal function. Patients of NZ European ethnicity had a lower 10-year risk of CVD. CONCLUSIONS: The study suggests that the diagnosis of T2D mediates the risk of CVD and HF in people with IGT. The development of risk scores to identify and better manage individuals with IGT at high risk of T2D is warranted.

Adverse Clinical Outcomes Attributable to Socioeconomic and Ethnic Disparities Among People with Type 2 Diabetes in New Zealand Between 1994-2018: A Multiple Linked Cohort Study.

Purpose: The study aimed to examine the separate population-level contributions of the ethnic and socioeconomic disparities among people with type 2 diabetes mellitus (T2DM) and residence in New Zealand (NZ). Patients and Methods: A prospective cohort enrolled T2DM patients from 01/01/1994 into the Diabetes Care Support Service, a primary care audit program in Auckland, NZ. The cohort was linked to national registry databases (socioeconomic status, pharmaceutical claim, hospitalization, and death registration). Each cohort member was followed up till death or the study end time (31/12/2019), whichever came first. Incident clinical events (stroke, myocardial infarction (MI), heart failure (HF), end-stage renal disease (ESRD), and premature mortality (PM)) were used as outcomes. The attributable fractions (AFs) were estimated for the whole population and for specific population with NZ Europeans (NZE) and/or least deprived population as reference, both unadjusted and with adjustment for covariables by Cox Regression models. Results: Among 36,267 patients, adjusted population AFs indicated 6.6(-30.8-33.3)% of PM, 17.1(5.8-27.0)% of MI, 35.3(22.6-46.0)% of stroke, 14.3(3.2-24.2)% of HF, and 15.9(6.7-24.2)% of ESRD could be attributed to deprivation; while 14.3(3.3-25.4)% of PM, -3.3(-8.3-1.5)% of MI, -0.5(-6.7-5.3)% of stroke, 4.7(0.3-8.8)% of HF, 13.3(9.9-16.6)% of ESRD could be attributed to ethnicity. Deprivation contributed a significant AF to stroke, while ethnicity was important for ESRD. Gradient of AF for deprivation indicated NZE and Asians were most affected by deprivation across outcomes. Conversely, Maori, with the highest AFs for ethnicity of PM and ESRD, were unaffected by deprivation. At same deprivations, the AFs of MI and stroke were greatest among NZE compared with other ethnic groups; the AF of ESRD was greatest among Maori and Pasifika. Conclusion: Both socioeconomic deprivation and ethnicity are strongly associated with outcomes in patients with T2DM in NZ, although the extent of the deprivation gradient is greatest among NZE and Asians, and least among Maori.

Ethnic differences in 25-year risk of incident chronic kidney disease among people with type 2 diabetes in New Zealand.

INTRODUCTION: Insights into ethnic differences in the natural history of chronic kidney disease (CKD) among people with type 2 diabetes mellitus (T2DM) might inform clinical strategies to address disparities in hospitalization and mortality. Risks of CKD II-V stages over a 25-year period between New Zealand Europeans (NZEs), Maori and Pasifika, and with T2DM in Auckland, New Zealand (NZ) were compared. RESEARCH DESIGN AND METHODS: As a primary care audit program in Auckland, the Diabetes Care Support Service was linked with national registration databases. People with existing CKD II-V were ruled out. To balance potential confounders, we applied a tapered matching method . 'Quasi-trial'-matched cohorts were set up separately between Maori and NZE and between Pasifika and NZE. Ethnic population differences in risk of any and each stage of CKD over 1994-2018 were examined by weighted Cox regression model. RESULTS: The HRs for developing any CKD, CKD stages II-V for Maori (n=2215) versus NZE (n=2028) were 1.18 (95% CI 0.99 to 1.41), 1.10 (95% CI 0.91 to 1.32), 1.70 (95% CI 1.19 to 2.43), 3.93 (95% CI 2.16 to 7.14), and 3.74 (95% CI 1.74 to 8.05), respectively. Compared with NZE (n=2474), the HRs for developing any CKD, CKD stages II-V for Pasifika (n=3101) were 1.31 (95% CI 1.09 to 1.57), 1.26 (95% CI 1.05 to 1.52), 1.71 (95% CI 1.14 to 2.57), 3.75 (95% CI 1.40 to 10.05), and 4.96 (95% CI 1.56 to 15.75), respectively. CONCLUSIONS: Among people with T2DM in NZ, significant ethnic differences exist in the risk of progressing to each stage of CKD (stage V in particular). Mechanism studies underlying these differences, as well as the need for identification of biomarkers to predict the early onset renal lesion, are warranted.

Are patients receiving recommended bone protection therapy after a non-hip fracture? A retrospective study of the Fracture Liaison Service at Counties Manukau District Health Board.

AIM: To review the Fracture Liaison Service (FLS) recommendations for bone protection therapy and assess treatment implementation in the community. METHOD: All patients screened from 1 January to 31 March 2019 at Counties Manukau District Health Board were evaluated. Exclusion criteria included death within six months following sentinel fracture, and hip fractures, which are studied elsewhere. Patient risk factors assessed included age, gender, type of fracture, history of previous fracture, and dual X-ray absorptiometry scan results if performed. If bone protection therapy was recommended, electronic dispensing records were utilised as a proxy for treatment initiation. RESULTS: One hundred and sixty-nine of the 238 patients referred were included. Thirty-seven patients had evidence of a previous fragility fracture, with thirteen patients not on bone protection treatment following their prior fracture. Of the 99 patients in the study recommended bone protection therapy, 31.3% (n=31) did not have this dispensed at six months following written FLS assessment. Three of thirteen patients with a previous fragility fracture and not on bone protection treatment, still did not have this dispensed at 6 months. CONCLUSION: A high proportion of patients recommended bone protection therapy did not receive this in a timely manner, including patients with a history of repeated fracture.

Ethnic differences in metabolic achievement between Maori, Pacific, and European New Zealanders with type 2 diabetes.

AIMS: To compare variations in metabolic target achievement by ethnicity (Europeans, Maori and Pasifika) among patients with type 2 diabetes (T2DM) in Auckland, New Zealand (NZ) between 1994 and 2013. METHODS: 32,237 patients were enrolled. Adjusted marginal difference (European as reference) of systolic blood pressure (SBP), body mass index (BMI), HbA1c and total cholesterol, alongside the proportion achieving metabolic targets were estimated using multivariable mixed effect models at baseline, 1-, 2-, 3-, 4-, and 5-years, adjusted for covariates. RESULTS: Compared with Europeans, Maori and Pasifika had continuously, significantly higher HbA1c (by 0.3% (+3.5 mmol/mol) and 0.6% (+6.8 mmol/mol) respectively and BMI (+1.5 and +0.3 kg/m2 respectively) but lower SBP (-1.8 and -3.4 mmHg respectively) and TG (-0.03 and -0.34 mmol/L respectively), and insignificantly TC (+0.004 and +0.01 respectively), by 5-years of follow-up. While 49% Europeans were within target HbA1c, this was achieved by only 30% Maori and 27% Pasifika. Conversely, 41% Europeans, 46% Maori and 59% Pasifika achieved the SBP target (all P < 0.0001). CONCLUSIONS: Managing hyperglycemia appears to be more challenging than treating hypertension and dyslipidemia among Maori and Pasifika. New anti-hyperglycemia treatments, addressing health literacy, socioeconomic and any cultural barriers to management and self-management are urgently needed to reduce these disparities.

Ethnic Differences in Cancer Rates Among Adults With Type 2 Diabetes in New Zealand From 1994 to 2018.

Importance: People with type 2 diabetes have greater risk for some site-specific cancers, and risks of cancers differ among racial and ethnic groups in the general population of Aotearoa New Zealand. The extent of ethnic disparities in cancer risks among people with type 2 diabetes in New Zealand is unclear. Objective: To compare the risks of 21 common adult cancers among Maori, Pasifika, and New Zealand European individuals with type 2 diabetes in New Zealand from 1994 to 2018. Design, Setting, and Participants: This population-based, matched cohort study used data from the primary care audit program in Auckland, New Zealand, linked with national cancer, death, and hospitalization registration databases, collected from January 1, 1994, to July 31, 2018, with follow-up data obtained through December 31, 2019. Using a tapered matching method to balance potential confounders (sociodemographic characteristics, lifestyle, anthropometric and clinical measurements, treatments [antidiabetes, antihypertensive, lipid-lowering, and anticoagulant], period effects, and recorded duration of diabetes), comparative cohorts were formed between New Zealand European and Maori and New Zealand European and Pasifika individuals aged 18 years or older with type 2 diabetes. Sex-specific matched cohorts were formed for sex-specific cancers. Exposures: Maori, Pasifika, and New Zealand European (reference group) ethnicity. Main Outcomes and Measures: The incidence rates of 21 common cancers recorded in nationally linked databases between 1994 and 2018 were the main outcomes. Weighted Cox proportional hazards regression was used to assess ethnic differences in risk of each cancer. Results: A total of 33 524 adults were included: 15 469 New Zealand European (mean [SD] age, 61.6 [13.2] years; 8522 [55.1%] male), 6656 Maori (mean [SD] age, 51.2 [12.4] years; 3345 [50.3%] female), and 11 399 Pasifika (mean [SD] age, 52.8 [12.7] years; 5994 [52.6%] female) individuals. In the matched New Zealand European and Maori cohort (New Zealand European: 8361 individuals; mean [SD] age, 58.9 [12.9] years; 4595 [55.0%] male; Maori: 5039 individuals; mean [SD] age, 51.4 [12.3] years; 2542 [50.5%] male), significant differences between New Zealand European and Maori individuals were identified in the risk for 7 cancers. Compared with New Zealand European individuals, the hazard ratios (HRs) among Maori individuals were 15.36 (95% CI, 4.50-52.34) for thyroid cancer, 7.94 (95% CI, 1.57-40.24) for gallbladder cancer, 4.81 (95% CI, 1.08-21.42) for cervical cancer (females only), 1.97 (95% CI, 1.30-2.99) for lung cancer, 1.81 (95% CI, 1.08-3.03) for liver cancer, 0.56 (95% CI, 0.35-0.90) for colon cancer, and 0.11 (95% CI, 0.04-0.27) for malignant melanoma. In the matched New Zealand European and Pasifika cohort (New Zealand European: 9340 individuals; mean [SD] age, 60.6 [13.1] years; 4885 [52.3%] male; Pasifika: 8828 individuals; mean [SD] age, 53.1 [12.6] years; 4612 [52.2%] female), significant differences between New Zealand European and Pasifika individuals were identified for 6 cancers. Compared with New Zealand European individuals, HRs among Pasifika individuals were 25.10 (95% CI, 3.14-200.63) for gallbladder cancer, 4.47 (95% CI, 1.25-16.03) for thyroid cancer, 0.48 (95% CI, 0.30-0.78) for colon cancer, 0.21 (95% CI, 0.09-0.48) for rectal cancer, 0.21 (95% CI, 0.07-0.65) for malignant melanoma, and 0.01 (95% CI, 0.01-0.10) for bladder cancer. Conclusions and Relevance: In this cohort study, differences in the risk of 21 common cancers were found between New Zealand European, Maori, and Pasifika groups of adults with type 2 diabetes in New Zealand from 1994 to 2018. Research into the mechanisms underlying these differences as well as additional screening strategies (eg, for thyroid and gallbladder cancers) appear to be warranted.

Stratified glucose-lowering response to vildagliptin and pioglitazone by obesity and hypertriglyceridemia in a randomized crossover trial.

Background: Understanding which group of patients with type 2 diabetes will have the most glucose lowering response to certain medications (which target different aspects of glucose metabolism) is the first step in precision medicine. Aims: We hypothesized that people with type 2 diabetes who generally have high insulin resistance, such as people of Maori/Pacific ethnicity, and those with obesity and/or hypertriglyceridemia (OHTG), would have greater glucose-lowering by pioglitazone (an insulin sensitizer) versus vildagliptin (an insulin secretagogue). Methods: A randomised, open-label, two-period crossover trial was conducted in New Zealand. Adults with type 2 diabetes, HbA1c>58mmol/mol (>7.5%), received 16 weeks of either pioglitazone (30mg) or vildagliptin (50mg) daily, then switched to the other medication over for another 16 weeks of treatment. Differences in HbA1c were tested for interaction with ethnicity or OHTG, controlling for baseline HbA1c using linear mixed models. Secondary outcomes included weight, blood pressure, side-effects and diabetes treatment satisfaction. Results: 346 participants were randomised (55% Maori/Pacific) between February 2019 to March 2020. HbA1c after pioglitazone was lower than after vildagliptin (mean difference -4.9mmol/mol [0.5%]; 95% CI -6.3, -3.5; p<0.0001). Primary intention-to-treat analysis showed no significant interaction effect by Maori/Pacific vs other ethnicity (1.5mmol/mol [0.1%], 95% CI -0.8, 3.7), and per-protocol analysis (-1.2mmol/mol [0.1%], 95% CI -4.1, 1.7). An interaction effect (-4.7mmol/mol [0.5%], 95% CI -8.1, -1.4) was found by OHTG status. Both treatments generated similar treatment satisfaction scores, although there was greater weight gain and greater improvement in lipids and liver enzymes after pioglitazone than vildagliptin. Conclusions: Comparative glucose-lowering by pioglitazone and vildagliptin is not different between Maori/Pacific people compared with other New Zealand ethnic groups. Presence of OHTG predicts greater glucose lowering by pioglitazone than vildagliptin. Clinical trial registration: www.anzctr.org.au, identifier (ACTRN12618001907235).

Cardiovascular risk prediction in type 2 diabetes before and after widespread screening: a derivation and validation study.

BACKGROUND: Until recently, most patients with diabetes worldwide have been diagnosed when symptomatic and have high cardiovascular risk, meaning most should be prescribed cardiovascular preventive medications. However, in New Zealand, a world-first national programme led to approximately 90% of eligible adults being screened for diabetes by 2016, up from 50% in 2012, identifying many asymptomatic patients with recent-onset diabetes. We hypothesised that cardiovascular risk prediction equations derived before widespread screening would now significantly overestimate risk in screen-detected patients. METHODS: New Zealanders aged 30-74 years with type 2 diabetes and without known cardiovascular disease, heart failure, or substantial renal impairment were identified from the 400 000-person PREDICT primary care cohort study between Oct 27, 2004, and Dec 30, 2016, covering the period before and after widespread screening. Sex-specific equations estimating 5-year risk of cardiovascular disease were developed using Cox regression models, with 18 prespecified predictors, including diabetes-related and renal function measures. Equation performance was compared with an equivalent equation derived in the New Zealand Diabetes Cohort Study (NZDCS), which recruited between 2000 and 2006, before widespread screening. FINDINGS: 46 652 participants were included in the PREDICT-1° Diabetes subcohort, of whom 4114 experienced first cardiovascular events during follow-up (median 5·2 years, IQR 3·3-7·4). 14 829 (31·8%) were not taking oral hypoglycaemic medications or insulin at baseline. Median 5-year cardiovascular risk estimated by the new equations was 4·0% (IQR 2·3-6·8) in women and 7·1% (4·5-11·2) in men. The older NZDCS equation overestimated median cardiovascular risk by three times in women (median 14·2% [9·7-20·0]) and two times in men (17·1% [4·5-20·0]). Model and discrimination performance measures for PREDICT-1° Diabetse equations were also significantly better than for the NZDCS equation (eg, for women: R2=32% [95% CI 29-34], Harrell's C=0·73 [0·72-0·74], Royston's D=1·410 [1·330-1·490] vs R2=24% [21-26], C=0·69 [0·67-0·70], and D=1·147 [1·107-1·187]). INTERPRETATION: International treatment guidelines still consider most people with diabetes to be at high cardiovascular risk; however, we show that recent widespread diabetes screening has radically changed the cardiovascular risk profile of people with diabetes in New Zealand. Many of these patients have normal renal function, are not dispensed glucose-lowering medications, and have low cardiovascular risk. These findings have clear international implications as increased diabetes screening is inevitable due to increasing obesity, simpler screening tests, and the introduction of new-generation glucose-lowering medications that prevent cardiovascular events. Cardiovascular risk prediction equations derived from contemporary diabetes populations, with multiple diabetes-related and renal function predictors, will be required to better differentiate between low-risk and high-risk patients in this increasingly heterogeneous population and to inform appropriate non-pharmacological management and cost-effective targeting of expensive new medications. FUNDING: Health Research Council of New Zealand, Heart Foundation of New Zealand, and Healthier Lives National Science Challenge.

Ethnic differences in mortality and hospital admission rates between Maori, Pacific, and European New Zealanders with type 2 diabetes between 1994 and 2018: a retrospective, population-based, longitudinal cohort study.

BACKGROUND: Type 2 diabetes affects Indigenous and non-European populations disproportionately, including in New Zealand, where long-term temporal trends in cause-specific clinical outcomes between Maori, Pacific, and European people remain unclear. We aimed to compare the rates of mortality and hospital admission between Maori, Pacific, and European patients with type 2 diabetes in Auckland, New Zealand, over a period of 24 years. METHODS: In this retrospective, population-based, longitudinal cohort study, we identified a cohort of patients (aged 35-84 years) with type 2 diabetes enrolled between Jan 1, 1994, and July 31, 2018, to the primary care audit programme, the Diabetes Care Support Service (DCSS) in Auckland, New Zealand. Patients with type 1 diabetes, prediabetes, and gestational diabetes were excluded. We linked data from the DCSS with national death registration, hospital admission, pharmaceutical claim, and socioeconomic status databases. Patients were followed up until death or July 31, 2018 (date of last enrolment to the DCSS). Incident clinical events (all-cause mortality, cardiovascular mortality, cancer mortality, cardiovascular hospital admission, cancer hospital admission, and end-stage renal disease hospital admission) were identified. Event rates were stratified by ethnic group, age group, sex, socioeconomic status, and time period (<1998, 1999-2013, 2004-08, 2009-13, and 2014-18). Incidence rate ratios (IRRs) and absolute risk differences were adjusted for sex, age, smoking status, obesity, socioeconomic status, and time period by use of age-period-cohort modelling. FINDINGS: Between Jan 1, 1994, and July 31, 2018, 45 072 patients with type 2 diabetes (21 936 [48·7%] female; mean age 56·7 years [SD 13·8]) were enrolled in the DCSS and followed up for a median of 9·7 years (IQR 5·8-13·6). 16 755 (37·2%) were European, 7093 (15·7%) were Maori, and 12 044 (26·7%) were Pacific patients. Despite a similar temporal trend (decreasing mortality and increasing hospital admissions) across the three ethnic groups, Maori and Pacific patients had consistently higher hospital admission rates than European patients. Maori but not Pacific patients had higher adjusted IRRs for all-cause mortality (1·96 [95% CI 1·80-2·14]), cardiovascular mortality (1·93 [1·63-2·29]) and cancer mortality (1·64 [1·40-1·93]) rates compared with European patients. INTERPRETATION: Compared with European patients, poorer health outcomes have persisted among Maori and Pacific people with type 2 diabetes for more than 20 years. New policies supporting prevention and more intensive management of type 2 diabetes are urgently needed. Research into the biological and societal mechanisms underlying these disparities, and the associated differences between Maori and Pacific patients is also needed. FUNDING: Counties Manukau Health and Middlemore Foundation.

Diabetic ketoacidosis admissions at Middlemore Hospital: observational study of cause and patient demographics.

AIM: To analyse data on diabetic ketoacidosis (DKA) admissions to better understand characteristics of those presenting with DKA and identify high-risk groups. METHOD: Study population consisted of people with type 1 diabetes discharged from Middlemore Hospital between 01 July 2015 and 30 June 2016 with the diagnosis of DKA. Basic demographic data and socioeconomic status as defined by 2013 New Zealand deprivation index quintiles were obtained, in addition to the cause of DKA. RESULTS: There were 69 DKA admissions from 57 people; 35% were Pasifika and 23% Maori. Fifty-six percent were from quintile 5, the quintile with the lowest socioeconomic status. The most common cause of DKA was non-adherence to insulin (59%), followed by infection (16%) and new diagnosis of type 1 diabetes (14%). There was greater proportion of Pasifika and Maori population in those with non-adherence as the cause. CONCLUSION: Non-adherence is a major cause of DKA admissions at Middlemore Hospital. When compared to the regional census data, there is over-representation of Pasifika and Maori population and those of lower socioeconomic status in those admitted with DKA. Similar pattern was seen in those with non-adherence as the cause of DKA and those with recurrent DKAs.

Randomised cross-over trial of vildagliptin and pioglitazone as add-on therapy in patients with type 2 diabetes: predicting Which One is Right Here (WORTH) study protocol.

INTRODUCTION: There is emerging evidence for stratified glucose-lowering responses to certain oral medications for type 2 diabetes (T2D) by individual characteristics. The objective of this study was to test whether glycaemic response to representative treatments of dipeptidyl peptidase-4 inhibitors (vildagliptin) and thiazolidinediones (pioglitazone) varies according to ethnicity, gender, baseline obesity, triglyceride level or genetic variation. METHODS: This is a multicentre, two-period, two-treatment, open-label, randomised cross-over trial of vildagliptin and pioglitazone as second-line or third-line therapy in patients with T2D who have suboptimal glycaemic control on metformin and/or sulfonylurea therapy. It is conducted in New Zealand with a target of 300 patients (40% with Maori or Pacific ancestry) eligible if aged ≥18 and ≤80 years, with T2D for more than 1 year, on stable doses of metformin and/or sulfonylurea for at least 3 months, with HbA1c between 59 and 110 mmol/mol inclusive. Participants are assigned to complete 4 months of vildagliptin 50 mg per day or pioglitazone 30 mg per day, followed by 4 months of the other medications in randomly allocated sequences. Participant characteristics, including ethnicity, obesity, lipid profile and candidate genotypes are collected at baseline. Primary outcome variable is on treatment HbA1c. Secondary outcomes include weight change, frequency of side effects and patient preference. ETHICS AND DISSEMINATION: Ethical approval of the trial has been obtained from the New Zealand Health and Disability Ethics Committee (18/STH/242). The trial commenced in February 2019 and recruitment is expected to be completed by March 2020. Results will be reported in articles submitted to peer-reviewed journals, as well as in presentations at national and international meetings. TRIAL REGISTRATION NUMBER: ACTRN12618001907235.