Trends in incidence and case fatality of acute myocardial infarction, angina and coronary revascularisation in people with and without type 2 diabetes in Scotland between 2006 and 2015.

AIMS/HYPOTHESIS: The aim of the study was to examine trends in the incidence and case fatality of acute myocardial infarction (AMI) and in hospital admissions for angina and coronary revascularisation procedures in people with type 2 diabetes and in people without diabetes in Scotland between 2006 and 2015. METHODS: In this retrospective cohort study, AMI, angina and revascularisation event data were obtained for adults from hospital admissions and death records linked to a population-based diabetes register. Incidence by diabetes status was estimated using negative binomial models with adjustment or stratification by age, sex, deprivation and calendar year. Logistic regression was used to estimate AMI case fatality by diabetes status. RESULTS: There were 129,926 incident AMI events, 41,263 angina admissions and 69,875 coronary revascularisation procedures carried out during 34.9 million person-years of follow-up. The adjusted incidence of AMI, angina and revascularisation procedures declined by 2.0% (95% CI 1.73%, 2.26%), 9.62% (95% CI 9.22%, 10.01%) and 0.35% (95% CI -0.09%, 0.79%) per year, respectively. The rate of decline did not differ materially by diabetes status. RRs of AMI for type 2 diabetes were 1.86 (95% CI 1.74, 1.98) for men and 2.32 (95% CI 2.15, 2.51) for women. Of the 77,211 people admitted to hospital with a first AMI, 7842 (10.2%) died within 30 days of admission. Case fatality was higher in people with type 2 diabetes than in people without diabetes and declined in both groups by 7.93% (95% CI 7.03%, 8.82%) per year. CONCLUSIONS/INTERPRETATION: The incidence of AMI, angina, revascularisation and AMI case fatality has declined over time, but the increased risk associated with type 2 diabetes has remained approximately constant.

Diabetes and pregnancy: national trends over a 15 year period.

AIMS/HYPOTHESIS: We aimed to examine time trends in national perinatal outcomes in pregnancies complicated by pre-existing type 1 or type 2 diabetes. METHODS: We analysed episode-level data on all obstetric inpatient delivery events (live or stillbirth) between 1 April 1998 and 31 March 2013 (n = 813,921) using the Scottish Morbidity Record (SMR02). Pregnancies to mothers with type 1 (n = 3229) and type 2 (n = 1452) diabetes were identified from the national diabetes database (Scottish Care Information-Diabetes), and perinatal outcomes were compared among women with type 1 diabetes, type 2 diabetes and those without diabetes. RESULTS: The number of pregnancies complicated by diabetes increased significantly, by 44% in type 1 diabetes and 90% in type 2 diabetes, across the 15 years examined, to rates of 1 in 210 and 1 in 504 deliveries, respectively. Compared with women without diabetes, delivery occurred 2.6 weeks earlier (type 1 diabetes 36.7 ± 2.3 weeks) and 2 weeks earlier (type 2 diabetes 37.3 ± 2.4 weeks), respectively, showing significant reductions for both type 1 (from 36.7 weeks to 36.4 weeks, p = 0.03) and type 2 (from 38.0 weeks to 37.2 weeks, p < 0.001) diabetes across the time period. The proportions of preterm delivery were markedly increased in women with diabetes (35.3% type 1 diabetes, 21.8% type 2 diabetes, 6.1% without diabetes; p < 0.0001), and these proportions increased with time for both groups (p < 0.005). Proportions of elective Caesarean sections (29.4% type 1 diabetes, 30.5% type 2 diabetes, 9.6% without diabetes) and emergency Caesarean sections (38.3% type 1 diabetes, 29.1% type 2 diabetes, 14.6% without diabetes) were greatly increased in women with diabetes and increased over time except for stable rates of emergency Caesarean section in type 1 diabetes. Gestational age-, sex- and parity-adjusted z score for birthweight (1.33 ± 1.34; p < 0.001) were higher in type 1 diabetes and increased over time from 1.22 to 1.47 (p < 0.001). Birthweight was also increased in type 2 diabetes (0.94 ± 1.34; p < 0.001) but did not alter with time. There were 65 perinatal deaths in offspring of mothers with type 1 diabetes and 39 to mothers with type 2 diabetes, representing perinatal mortality rates of 20.1 (95% CI 14.7, 24.3) and 26.9 (16.7, 32.9) per 1000 births, respectively, and rates 3.1 and 4.2 times, respectively, those observed in the non-diabetic population (p < 0.001). Stillbirth rates in type 1 and type 2 diabetes were 4.0-fold and 5.1-fold that in the non-diabetic population (p < 0.001). Perinatal mortality and stillbirth rates showed no significant fall over time despite small falls in the rates for the non-diabetic population. CONCLUSIONS/INTERPRETATION: Women with diabetes are receiving increased intervention in pregnancy (earlier delivery, increased Caesarean section rates), but despite this, higher birthweights are being recorded. Improvements in rates of stillbirth seen in the general population are not being reflected in changes in stillbirth or perinatal mortality in our population with diabetes.

Cancer incidence in persons with type 1 diabetes: a five-country study of 9,000 cancers in type 1 diabetic individuals.

AIMS/HYPOTHESIS: An excess cancer incidence of 20-25% has been identified among persons with diabetes, most of whom have type 2 diabetes. We aimed to describe the association between type 1 diabetes and cancer incidence. METHODS: Persons with type 1 diabetes were identified from five nationwide diabetes registers: Australia (2000-2008), Denmark (1995-2014), Finland (1972-2012), Scotland (1995-2012) and Sweden (1987-2012). Linkage to national cancer registries provided the numbers of incident cancers in people with type 1 diabetes and in the general population. We used Poisson models with adjustment for age and date of follow up to estimate hazard ratios for total and site-specific cancers. RESULTS: A total of 9,149 cancers occurred among persons with type 1 diabetes in 3.9 million person-years. The median age at cancer diagnosis was 51.1 years (interquartile range 43.5-59.5). The hazard ratios (HRs) (95% CIs) associated with type 1 diabetes for all cancers combined were 1.01 (0.98, 1.04) among men and 1.07 (1.04, 1.10) among women. HRs were increased for cancer of the stomach (men, HR 1.23 [1.04, 1.46]; women, HR 1.78 [1.49, 2.13]), liver (men, HR 2.00 [1.67, 2.40]; women, HR 1.55 [1.14, 2.10]), pancreas (men, HR 1.53 [1.30, 1.79]; women, HR 1.25 [1.02,1.53]), endometrium (HR 1.42 [1.27, 1.58]) and kidney (men, HR 1.30 [1.12, 1.49]; women, HR 1.47 [1.23, 1.77]). Reduced HRs were found for cancer of the prostate (HR 0.56 [0.51, 0.61]) and breast (HR 0.90 [0.85, 0.94]). HRs declined with increasing diabetes duration. CONCLUSION: Type 1 diabetes was associated with differences in the risk of several common cancers; the strength of these associations varied with the duration of diabetes.

Trends in type 2 diabetes incidence and mortality in Scotland between 2004 and 2013.

AIMS/HYPOTHESIS: The relative contribution of increasing incidence and declining mortality to increasing prevalence of type 2 diabetes in Scotland is unclear. Trends in incidence and mortality rates are described for type 2 diabetes in Scotland between 2004 and 2013 by age, sex and socioeconomic deprivation. METHODS: Data for incident and prevalent cases of type 2 diabetes were obtained from the Scottish national diabetes register with number of deaths identified from linkage to mortality records. Population size and death data for Scotland by age, sex and socioeconomic deprivation were obtained from National Records of Scotland. Age- and sex-specific incidence and mortality rates stratified by year and deciles of socioeconomic status were calculated using Poisson models. RESULTS: There were 180,290 incident cases of type 2 diabetes in Scotland between 2004 and 2013. Overall, incidence of type 2 diabetes remained stable over time and was 4.88 (95% CI 4.84, 4.90) and 3.33 (3.28, 3.32) per 1000 in men and women, respectively. However, incidence increased among young men, remained stable in young women, and declined in older men and women. Incidence rates declined in all socioeconomic groups but increased after 2008 in the most deprived groups. Standardised mortality ratios associated with diabetes, adjusted for age and socioeconomic group, were 1.38 (1.36, 1.41) in men and 1.49 (1.45, 1.52) in women, and remained constant over time. CONCLUSIONS/INTERPRETATION: Incidence of type 2 diabetes has stabilised in recent years suggesting that increasing prevalence may be primarily attributed to declining mortality. Prevention of type 2 diabetes remains important, particularly among socioeconomically deprived populations.

Trends in disease incidence and survival and their effect on mortality in Scotland: nationwide cohort study of linked hospital admission and death records 2001-2016.

OBJECTIVES: Identify causes and future trends underpinning Scottish mortality improvements and quantify the relative contributions of disease incidence and survival. DESIGN: Population-based study. SETTING: Linked secondary care and mortality records across Scotland. PARTICIPANTS: 1 967 130 individuals born between 1905 and 1965 and resident in Scotland from 2001 to 2016. MAIN OUTCOME MEASURES: Hospital admission rates and survival within 5 years postadmission for 28 diseases, stratified by sex and socioeconomic status. RESULTS: 'Influenza and pneumonia', 'Symptoms and signs involving circulatory and respiratory systems' and 'Malignant neoplasm of respiratory and intrathoracic organs' were the hospital diagnosis groupings associated with most excess deaths, being both common and linked to high postadmission mortality. Using disease trends, we modelled a mean mortality HR of 0.737 (95% CI 0.730 to 0.745) from one decade of birth to the next, equivalent to a life extension of ~3 years per decade. This improvement was 61% (30%-93%) accounted for by improved disease survival after hospitalisation (principally cancer) with the remainder accounted for by lowered hospitalisation incidence (principally heart disease and cancer). In contrast, deteriorations in infectious disease incidence and survival increased mortality by 9% (~3.3 months per decade). Disease-driven mortality improvements were slightly greater for men than women (due to greater falls in disease incidence), and generally similar across socioeconomic deciles. We project mortality improvements will continue over the next decade but slow by 21% because much progress in disease survival has already been achieved. CONCLUSION: Morbidity improvements broadly explain observed mortality improvements, with progress on prevention and treatment of heart disease and cancer contributing the most. The male-female health gaps are closing, but those between socioeconomic groups are not. Slowing improvements in morbidity may explain recent stalling in improvements of UK period life expectancies. However, these could be offset if we accelerate improvements in the diseases accounting for most deaths and counteract recent deteriorations in infectious disease.

A case study in distributed team science in research using electronic health records.

INTRODUCTION: Due to various regulatory barriers, it is increasingly difficult to move pseudonymised routine health data across platforms and among jurisdictions. To tackle this challenge, we summarized five approaches considered to support a scientific research project focused on the risk of the new non-vitamin K Target Specific Oral Anticoagulants (TSOACs) and collaborated between the Farr institute in Wales and Scotland. APPROACH: In Wales, routinely collected health records held in the Secure Anonymous Information Linkage (SAIL) Databank were used to identify the study cohort. In Scotland, data was extracted from national dataset resources administered by the eData Research & Innovation Service (eDRIS) and stored in the Scottish National Data Safe Haven. We adopted a federated data and multiple analysts approach, but arranged simultaneous accesses for Welsh and Scottish analysts to generate study cohorts separately by implementing the same algorithm. Our study cohort across two countries was boosted to 6,829 patients towards risk analysis. Source datasets and data types applied to generate cohorts were reviewed and compared by analysts based on both sites to ensure the consistency and harmonised output. DISCUSSION: This project used a fusion of two approaches among five considered. The approach we adopted is a simple, yet efficient and cost-effective method to ensure consistency in analysis and coherence with multiple governance systems. It has limitations and potentials of extending and scaling. It can also be considered as an initialisation of a developing infrastructure to support a distributed team science approach to research using Electronic Health Records (EHRs) across the UK and more widely.