Comparative trends in the incidence of hospitalized myocardial infarction and coronary heart disease in adults with and without diabetes mellitus in Western Australia from 1998 to 2010

Sex-specific trends in incidence of first myocardial infarction among people with and without diabetes between 1985 and 2016 in a German region

BACKGROUND

The reduction of myocardial infarction (MI) and narrowing the gap between the populations with and without diabetes are important goals of diabetes care. We analyzed time trends for sex-specific incidence rates (IR) of first MI (both non-fatal MI and fatal MI) as well as separately for first non-fatal MI and fatal MI in the population with and without diabetes.

METHODS

Using data from the KORA myocardial infarction registry (Augsburg, Germany), we estimated age-adjusted IR in people with and without diabetes, corresponding relative risks (RR), and time trends from 1985 to 2016 using Poisson regression.

RESULTS

There were 19,683 people with first MI (34% fatal MI, 71% men, 30% with diabetes) between 1985 and 2016. In the entire study population, the IR of first MI decreased from 359 (95% CI: 345-374) to 236 (226-245) per 100,000 person years. In men with diabetes, IR decreased only in 2013-2016. This was due to first non-fatal MI, where IR in men with diabetes increased until 2009-2012, and slightly decreased in 2013-2016. Overall, fatal MI declined stronger than first non-fatal MI corresponding to IRs. The RR of first MI substantially increased among men from 1.40 (1.22-1.61) in 1985-1988 to 2.60 (2.26-2.99) in 1997-2000 and moderately decreased in 2013-2016: RR: 1.75 (1.47-2.09). Among women no consistent time trend for RR was observed. Time trends for RR were similar regarding first non-fatal MI and fatal MI.

CONCLUSIONS

Over the study period, we found a decreased incidence of first MI and fatal MI in the entire study population. The initial increase of first non-fatal MI in men with diabetes needs further research. The gap between populations with and without diabetes remained.

Long-term trends in population-based hospitalisation rates for myocardial infarction in England: a national database study of 3.5 million admissions, 1968-2016

AIM

To analyse the timing and scale of temporal changes in rates of hospitalised myocardial infarction (MI) in England by age and sex from 1968 to 2016.

METHODS

MI admissions for adults aged 15-84 years were identified from electronic hospital data. We calculated age-standardised and age-specific rates, and examined trends using joinpoint.

RESULTS

From 1968 to 2016, there were 3.5 million admissions for MI in England (68% men). Rates increased in the early years of the study in both men and women, peaked in the mid-1980s (355 per 100 000 population in men; 127 in women) and declined by 38.8% in men and 37.4% in women from 1990 to 2011. From 2012, however, modest increases were observed in both sexes. Long-term trends in rates over the study period varied by age and sex, with those aged 70 years and older having the greatest and most sustained increases in the early years (1968-1985). During subsequent years, rates decreased in most age groups until 2010-2011. The exception was younger women (35-49 years) and men (15-34 years) who experienced significant increases from the mid-1990s to 2007 (range +2.1%/year to 4.7%/year). From 2012 onwards, rates increased in all age groups except the oldest, with the most marked increases in men aged 15-34 years (7.2%/year) and women aged 40-49 (6.9%-7.3%/year) .

CONCLUSION

Despite substantial declines in hospital admission rates for MI in England since 1990, the burden of annual admissions remains high. Continued surveillance of trends and coronary disease preventive strategies are warranted.

Clinical Characteristics, Prognosis, and Gender Disparities in Young Patients With Acute Myocardial Infarction

Background: Young people hold a stable or increasing percentage of patients with acute myocardial infarction (AMI) in many countries. However, data on clinical characteristics and outcomes of young AMI patients were insufficient. This study aimed to analyze clinical characteristics, prognosis, and gender disparities in patients aged ≤45 years with AMI. Methods: A total of 24,125 patients from China Acute Myocardial Infarction registry were included in this study. Clinical characteristics, managements, and in-hospital and 2-year outcomes were compared between patients aged ≤45 years and those aged >45 years. Predictors of all-cause death were obtained using multivariate regression models. Gender disparities of AMI were analyzed among young patients. Results: Of 24,125 patients, 2,042 (8.5%, 116 female) were aged ≤45 years. Compared with patients aged >45 years, young patients were more often male, current smokers, and more likely to have medical history of hyperlipidemia. Smoking (72.1%) was the major modifiable risk factor in patients aged ≤45 years. Young patients received more evidence-based medications and had significantly lower risk of both in-hospital and 2-year adverse events than older patients. Education level and left ventricular ejection fraction were independent predictors of 2-year mortality in young patients. Moreover, symptom onset to admission time of young women was significantly longer than that of young men. Young women were less likely to receive percutaneous coronary intervention and suffered higher risk of in-hospital adverse events than young men (adjusted odds ratio for death: 5.767, 95% confidence interval 1.580-21.049, p = 0.0080; adjusted odds ratio for the composite of death, re-infarction, and stroke: 3.981, 95% confidence interval 1.150-13.784, p = 0.0292). Young women who survived at discharge had a higher 2-year cumulative incidence of death (3.8 vs 1.4%, p log-rank = 0.0412). Conclusions: Patients aged ≤45 years constituted a non-negligible proportion of AMI patients, with higher prevalence of smoking and hyperlipidemia but better care and prognosis compared with older patients. There were significant gender disparities of managements and outcomes in young patients. More efforts to improve quality of care in young women are needed.

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.

Trends in age- and sex-specific prevalence and incidence of cardiovascular disease in Western Australia

Background Temporal trends in incidence and mortality of cardiovascular disease (CVD) have been well described, with recent data suggesting declining improvements in those aged under 55 years. However, little is known about the combined impact of incidence and mortality trends on disease prevalence, an important indicator of disease burden and cost. We analysed changes in age-specific and age-standardised temporal trends in prevalence and incidence of CVD subtypes. Methods Annual prevalence and incidence rates of coronary heart disease, cerebrovascular disease and peripheral arterial disease for the Western Australian population for 1995-2010 were calculated using data from the Western Australian Data Linkage System. Joinpoint regression analyses were used to identify joinpoints in trends in age-specific and age-standardised annual prevalence and incidence rates for each CVD subtype. Results Between 1995 and 2010, age- and sex-specific incidence and prevalence of the CVD subtypes generally decreased among middle-aged and older adults, but were stable or increased among younger adults. In < 55 year olds, increases in incidence tended to occur from 2003, while increases in prevalence were from 2007/2008. Declines in age-standardised incidence were greater than those in crude incidence, with changes in population structure having a greater impact among men than women. Conclusions The majority of CVDs occurs in older adults. Our findings of generally worsening trends in prevalence in younger adults across most CVD subtypes were in contrast to generally declining trends in older age groups. These data highlight the importance of monitoring prevalence and incidence, particularly in younger adults.

Identification of myocardial infarction type from electronic hospital data in England and Australia: a comparative data linkage study

OBJECTIVE

To determine the utility of International Classification of Diseases (ICD) codes in investigating trends in ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI) using person-linked electronic hospitalisation data in England and Western Australia (WA).

METHODS

All hospital admissions with myocardial infarction (MI) as the principal diagnosis were identified from 2000 to 2013 from both jurisdictions. Fourth-digit ICD-10 codes were used to delineate all MI types-STEMI, NSTEMI, unspecified and subsequent MI. The annual frequency of each MI type was calculated as a proportion of all MI admissions. For all MI and each MI type, age-standardised rates were calculated and age-adjusted Poisson regression models used to estimate annual percentage changes in rates.

RESULTS

In 2000, STEMI accounted for 49% of all MI admissions in England and 59% in WA, decreasing to 35% and 25% respectively by 2013. Less than 10% of admissions were recorded as NSTEMI in England throughout the study period, whereas by 2013, 70% of admissions were NSTEMI in WA. Unspecified MI comprised 60% of all MI admissions in England by 2013, compared with <1% in WA. Trends in age-standardised rates differed for all MI (England, -2.7%/year; WA, +1.7%/year), underpinned by differing age-adjusted trends in NSTEMI (England, -6.1%/year; WA, +10.2%/year).

CONCLUSION

Differences between the proportion and trends for MI types in English and WA data were observed. These were consistent with the coding standards in each country. This has important implications for using electronic hospital data for monitoring MI and identifying MI types for outcome studies.

Cardiovascular complications and drug prescriptions in subjects with and without diabetes in a Northern region of Italy, in 2002 and 2012

BACKGROUND AND AIMS

In contrast to the well-documented global prevalence of diabetes, much less is known about the epidemiology of cardiovascular (CV) complications in recent years. We describe the incidence of major CV events, deaths and drug prescribing patterns from 2002 to 2012 in subjects with (DM) or without diabetes mellitus (No DM).

METHODS AND RESULTS

Subjects and outcomes were identified using linkable health administrative databases of Lombardy, a region in Northern Italy. A logistic regression model was used to compare myocardial infarction (MI), stroke, major amputation and death between DM and No DM in 2002 and 2012 and between the two index years in each population. The interaction between years and diabetes was introduced in the model. From 2002 to 2012 the incidence of major CV complications and death fell in both groups with a larger reduction among DM only for CV events: OR (95% CI) for the interaction 0.86 (0.79-0.93) for MI, 0.89 (0.82-0.96) for stroke, 0.78 (0.57-1.06) for major amputations. CV prevention drugs rose considerably from 2002 to 2012 particularly in DM and a switch towards safer antihyperglycemic drugs was also observed.

CONCLUSIONS

Major CV complications and death declined from 2002 to 2012 in both DM and No DM. This might be due to a larger increase in prescriptions of CV drugs in DM and a relevant change toward recommended antihyperglycemic drugs.

Long-term all-cause and cardiovascular mortality following incident myocardial infarction in men and women with and without diabetes: Temporal trends from 1998 to 2009

BACKGROUND

Long-term mortality following myocardial infarction is higher in diabetic than non-diabetic individuals. Early case-fatality after myocardial infarction has improved but it is unclear whether trends extend to long-term mortality. We aimed to determine whether the disparity in long-term all-cause and cardiovascular disease mortality by diabetes status has decreased.

METHODS

All incident myocardial infarction cases were identified from Western Australian whole-population linked data for 1998-2009. Mortality follow-up was available until 30 June 2011. Unadjusted survival was estimated using Kaplan-Meier survival curves. Hazard ratios comparing five-year mortality in diabetic versus non-diabetic people across three periods (1998-2001, 2002-2005, 2006-2009) were estimated from multivariable Cox regression models, and adjusted trends calculated from interaction (diabetes status × period) models.

RESULTS

There were 22,594 30-day survivors of incident MI. There was little change across the three periods in all-cause mortality in diabetic men (27.1%, 28.2%, 25.5%) and women (34.9%, 36.8%, 36.1%), but small declines from first to last periods in non-diabetic men (14.5% to 12.1%, p = 0.03) and women (21.0% to 19.4%, p = 0.08). There was no temporal change in the increased all-cause mortality hazard ratios in diabetic versus non-diabetic men and women. Multivariable-adjusted relative risk for cardiovascular disease mortality remained elevated in diabetic women (2006-2009 hazard ratio 1.73, 95% confidence interval 1.29, 2.32) but not in men (2006-2009 hazard ratio 1.08, 95% confidence interval 0.85, 1.37).

CONCLUSIONS

The excess long-term mortality associated with diabetes and excess cardiovascular disease mortality in diabetic women indicates a need for improved secondary prevention in diabetic patients, especially women.

Improving 30-day case fatality after incident myocardial infarction in people with diabetes between 1998 and 2010

OBJECTIVE

To compare population-level trends in 30-day case fatality following incident myocardial infarction (MI) in people with diabetes and those without diabetes.

METHODS

We identified all hospitalised incident MIs in 35-84 year olds from the Western Australian Data Linkage System for 1998-2010, stratified by diabetes status. Crude and age- and sex-standardised 30-day case fatality were estimated, and age- and sex-adjusted trends were calculated from logistic regression. We calculated the trend in risk of 30-day death associated with diabetes from multivariable logistic regression, adjusting for demographics, comorbidities and MI type.

RESULTS

26 610 hospitalised incident MI cases were identified, 24.8% of whom had diabetes. The prevalence of heart failure fell in people with diabetes, concurrent with increasing chronic kidney disease and prior coronary heart disease and increasing levels of evidence-based therapies. Case fatality in people with diabetes fell from 11.65%, in 1998-2001, to 3.96% by 2008-2010. Age- and sex-standardised case fatality declined at a greater rate in those with diabetes (-10.6%/year, 95% CI -12.8% to -8.2%) compared to non-diabetics (-6.9%/year, 95% CI -8.3% to -5.3%; interaction p=0.005). The adjusted risk of 30-day death after incident MI was 1.23 times higher in diabetics than non-diabetics in 1998-2001 (95% CI 1.01 to 1.50), but was lower by 2008-2010 (OR 0.64, 95% CI 0.46 to 0.88).

CONCLUSIONS

Greater improvements in 30-day case fatality following incident MI in people with diabetes during the 13-year study period has led to diabetes no longer being an independent predictor of early death following incident MI by 2008-2010.

Temporal trends in initial and recurrent lower extremity amputations in people with and without diabetes in Western Australia from 2000 to 2010

AIMS

To examine temporal trends in lower extremity amputations in people with type 1 diabetes, type 2 diabetes and cardiovascular disease (CVD) without diabetes in Western Australia (WA) from 2000 to 2010.

METHODS

We used linked health data to identify all non-traumatic lower extremity amputations in adults aged ≥20 years with diabetes and/or CVD from 2000 to 2010 in WA. Annual age- and sex-standardised rates of total, initial and recurrent amputations, stratified by major and minor status, were calculated for type 1 and type 2 diabetes, and CVD without diabetes, from the at-risk population for each group. Age- and sex-adjusted trends were estimated from Poisson regression models.

RESULTS

5891 lower extremity amputations were identified. Peripheral vascular disease (71%), hypertension (70%) and chronic kidney disease (60%) were highly prevalent. Average annual rates of total amputations were 724, 564 and 66 per 100,000 person-years in type 1, type 2 diabetes and CVD without diabetes respectively. Rates of initial amputations fell significantly by 2.4%/year (95% CI -3.5, -1.4) in type 2 diabetes, with similar declines for type 1 diabetes and CVD without diabetes (interaction p=0.96), driven by large falls in major amputations. There was limited improvement in recurrence rates overall, with recurrent minor amputations increasing significantly in type 2 diabetes (+3.5%/year, 95% CI +1.3%, +5.7%).

CONCLUSION

Lower extremity amputation rates have declined at a population level in people with diabetes and CVD without diabetes, suggesting improvements in prevention and management for this high-risk patient group, however limited declines in recurrent amputations requires further investigation.