Kok Wai Giang

Twenty-Four-Year Trends in the Incidence of Ischemic Stroke in Sweden From 1987 to 2010

Background and Purpose— The incidence of stroke in Sweden increased between 1989 and 2000 among people aged ⩽65 years, but more recent data on those aged >65 years are lacking. Methods— Through the Swedish Hospital Discharge and Cause of Death registries, we identified all cases of nonfatal and fatal ischemic stroke (IS) among people aged 18 to 84 years during 1987–2010 in Sweden. Results— Of the 391 081 stroke cases identified, 1.6% were 18 to 44 years, 16.7% were 45 to 64 years, and 81.7% were 65 to 84 years. Among people aged 18 to 44 years, there was a continuous increase in the incidence of stroke of 1.3% (95% confidence interval, 0.8%–1.8%) per year for men and 1.6% (1.0%–2.3%) per year for women. Among men and women aged 45 to 64 years, slightly declining rates were observed from the late 1990s, with a mean annual decrease of 0.4% (0.1%–0.7%) among men and 0.6% (0.2%–1.0%) among women. Among men aged 65 to 84 years, a decrease of 3.7% in IS (3.4%–4.0%) per year was observed from the late 1990s. This was more marked in women, where an initial decrease of 2.5% (2.1%–2.9%) per year was followed by an accelerated decrease of 5.1% (4.4%–5.8%) after 2005. Mortality from IS decreased markedly in all age groups. Conclusions— The incidence of IS in elderly people in Sweden is now decreasing, whereas the decline in IS incidence in the middle-aged people is much less steep. The increasing incidence of stroke in the young, particularly if carried forward to an older age, is concerning.

Perceived stress and incidence of Type 2 diabetes: a 35-year follow-up study of middle-aged Swedish men

To explore incident cases of diagnosed diabetes over 35 years of follow‐up in relation to self‐perceived stress at baseline.

Sex-specific trends in 4-year survival in 37 276 men and women with acute myocardial infarction before the age of 55 years in Sweden, 1987-2006: a register-based cohort study

Objective To examine sex-specific trends in 4-year mortality among young patients with first acute myocardial infarction (AMI), 1987–2006. Design Prospective cohort study. Setting Sweden. Participants We identified 37 276 cases (19.4% women; age, 25–54 years) from the Swedish Inpatient Register, 1987–2006, who had survived 28 days after an AMI. Outcome measures 4-year mortality from all causes and standard mortality ratio (SMR). Results From the first to last 5-year period, the absolute excess risk decreased from 1.38 to 0.50 and 1.53 to 0.59 per 100 person-years among men aged 25–44 and 45–54 years, respectively. Corresponding figures for women were a decrease from 2.26 to 1.17 and from 1.93 to 1.45 per 100 person-years, respectively. Trends for women were non-linear, decreasing to the same extent as those for men until the third period, then increasing. For the last 5-year period, the standardised mortality ratio for young survivors of AMI compared with the general population was 4.34 (95% CI 3.04 to 5.87) and 2.43 (95% CI 2.12 to 2.76) for men aged 25–44 and 45–54 years, respectively, and 13.53 (95% CI 8.36 to 19.93) and 6.42 (95% CI 5.24 to 7.73) for women, respectively. Deaths not associated with cardiovascular causes increased from 21.5% to 44.6% in men and 41.5% to 65.9% in women. Conclusions Young male survivors of AMI have low absolute long-term mortality rates, but these rates remain twofold to fourfold that of the general population. After favourable development until 2001, women now have higher absolute mortality than men and a 6-fold to 14-fold risk of death compared with women in the general population.

The association between job strain and atrial fibrillation in Swedish men

Objectives The purpose of this study was to investigate whether psychosocial stress defined as high strain based on the job demand–control model increases risk for atrial fibrillation. Methods The present study comprised 6035 men born between 1915 and 1925 and free from previous coronary heart disease, atrial fibrillation and stroke at baseline (1974–1977). Work-related psychosocial stress was measured using a job-exposure matrix for the job demand–control model based on occupation at baseline. The participants were followed from baseline examination until death, hospital discharge or 75 years of age, using the Swedish national register on cause of death and the Swedish hospital discharge register for any registration for atrial fibrillation, resulting in the identification of 436 cases. Data were analysed with Cox regression models with atrial fibrillation as the outcome using high strain as the explanatory variable adjusted for age, smoking, body mass index, hypertension, diabetes and socioeconomic status. Results There was an increased risk for atrial fibrillation in relation to high strain (HR 1.32, 95% CI 1.003 to 1.75). When the four categories of the job-strain model were included and low strain was used as reference, the risk for high strain decreased (HR 1.23, 95% CI 0.84 to 1.82). Conclusions Exposure to occupational psychosocial stress defined as high strain may be associated with increased risk for atrial fibrillation. The observed increase in risk is small and residual confounding may also be present.

Twenty-Year Trends in Long-term Mortality Risk in 17 149 Survivors of Ischemic Stroke Less Than 55 Years of Age

Background and Purpose— The purpose of the present study was to investigate the 4-year mortality risk among patients <55 years with a first ischemic stroke during 1987–2006. Methods— A total of 17 149 cases (37.4% women) aged 18 to 54 years who survived ≥28 days after a first ischemic stroke were identified in the Swedish Inpatient Register from 1987 to 2006. All patients were followed for 4 years or until death. The standardized mortality ratio was calculated by comparing the mortality rates with those of the general population of equivalent age, sex, and calendar year. Results— During the period, there were 1265 deaths. Long-term survival improved over time in both men and women. Among men, the mortality risk decreased by 32% (hazard ratio=0.68 [95% confidence interval, 0.56–0.82]) from the first 5-year period to the last 5-year period (1987–1991 versus 2002–2006), and among women, the mortality risk decreased by 45% (0.55 [0.41–0.75]). Despite an overall decrease in mortality, the standardized mortality ratios for the last 5-year period remained high: 5.88 (95% confidence interval, 5.10–6.71) for men and 5.91 (4.68–7.29) for women with an absolute excess risk of 1.60 and 0.97 per 100 person-years, respectively, with nearly half of all deaths related to cardiovascular disease. Conclusions— During the 20-year period, 4-year mortality decreased by one third but was still 6-fold higher than that of the general population in the most recent period, emphasizing the importance of secondary prevention in young persons who have had a stroke.

Trends in risk of recurrence after the first ischemic stroke in adults younger than 55 years of age in Sweden

Background Previous studies on stroke recurrence in younger adults often contain small sample size which makes it difficult to study trends in stroke recurrence over a long period of time. Aims The aim of the present study was to investigate temporal trends in the risk of recurrence in younger patients with a first ischemic stroke. Methods All men and women aged 18–54 years who had survived at least 28 days after a first ischemic stroke from 1987 to 2006 were identified in the Swedish Inpatient Register. The patients were stratified into four 5-year periods according to their admission period and were followed up for a total of four years after the index event with regard to recurrent ischemic stroke. A Cox regression model was used to analyze the risk of recurrent ischemic stroke. Results Of the 17,149 ischemic stroke patients who were identified, 2432 (14.2%) had a recurrent ischemic stroke event within four years. From the first to the last periods (1987–1991 versus 2002–2006), the four-year risk of recurrent ischemic stroke decreased by 55% (hazard ratio 0.45, 95% confidence interval 0.39–0.53) in men and 59% (hazard ratio 0.41, 95% confidence interval, 0.33–0.50) in women. The cumulative four-year risk was 11.8% (95% CI 10.55–13.25) in men and 9.8% (95% CI 8.40–11.46) in women during the last five-year period (2002–2006). Conclusions The risk of recurrence among younger ischemic stroke patients has decreased over the past 20 years. Despite these improvements, younger patients are still at a high risk for recurrent ischemic stroke.

Stroke and coronary heart disease: predictive power of standard risk factors into old age—long-term cumulative risk study among men in Gothenburg, Sweden

Aims The aim of this study was to examine the short-term and long-term cumulative risk of coronary heart disease (CHD) and stroke separately based on age, sex, smoking status, systolic blood pressure, and total serum cholesterol. Methods and results The Primary Prevention Study comprising 7174 men aged between 47 and 55 free from a previous history of CHD, stroke, and diabetes at baseline examination (1970–73) was followed up for 35 years. To estimate the cumulative effect of CHD and stroke, all participants were stratified into one of five risk groups, defined by their number of risk factors. The estimated 10-year risk for high-risk individuals when adjusted for age and competing risk was 18.1% for CHD and 3.2% for stroke which increased to 47.8 and 19.6%, respectively, after 35 years. The estimates based on risk factors performed well throughout the period for CHD but less well for stroke. Conclusion The prediction of traditional risk factors (systolic blood pressure, total serum cholesterol, and smoking status) on short-term risk (0–10 years) and long-term risk (0–35 years) of CHD of stroke differs substantially. This indicates that the cumulative risk in middle-aged men based on these traditional risk factors can effectively be used to predict CHD but not stroke to the same extent.

Trends in mortality risks among 94,328 patients surviving 30 days after a first isolated coronary artery bypass graft procedure from 1987 to 2006: A population-based study

BACKGROUND Updated knowledge about survival after coronary artery bypass graft (CABG) surgery is needed. We examined 20-year trends in 4-year survival after a first isolated CABG procedure, compared with that of the general population. METHODS We identified 94,328 patients surviving 30days after a first isolated CABG 1987-2006 from the Swedish Inpatient Register. RESULTS Crude annual mortality rates remained stable at approximately 1% in patients aged 18-54years and at approximately 2% in those aged ≥55years. After adjustment for comorbidities, 4-year survival in men aged 18-54 and ≥55years improved by 37% (HR: 0.63, 95% CI, 0.46-0.88) and 31% (HR: 0.69, 95% CI, 0.63-0.76), respectively, (1987-1991 vs. 2002-2006). The corresponding estimate for women aged ≥55years was 38% (HR: 0.62, 95% CI, 0.52-0.75), with no significant change in survival in women aged <55years (HR: 1.02, 95% CI, 0.52-2.03). Men and women aged <55years had higher mortality than the general population, with standardized mortality ratios (SMR) of 1.76 (95% CI, 1.35-2.22) in men and 4.49 (95% CI, 2.74-6.68) in women during the last period (2002-2006). In contrast, patients aged ≥55years had better survival with a SMR of 0.74 (95% CI, 0.70-0.78) in men and 0.82 (95% CI, 0.74-0.91) in women during 2002-2006. CONCLUSION During 1987-2006, there was a significant improvement in survival after CABG for all categories, except in women aged <55years. Men and women aged ≥55years who survived the first 30days after CABG had a lower mortality risk than the general population.

Long-Term Risk of Hemorrhagic Stroke in Young Patients With Congenital Heart Disease.

Background and Purpose— The risk of ischemic stroke is increased in patients with congenital heart disease (CHD); however, data on the risk of hemorrhagic stroke, including intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH), are lacking. Methods— The Swedish Patient Register was used to identify all patients who were born with a diagnosis of CHD between 1970 and 1993. Each patient was compared with 10 randomly selected controls from the general population, matched for age, sex, and county. Follow-up data were collected until December 2011 for both cases and controls. Results— Of 21 982 patients with CHD, 70 developed ICH and 57 developed SAH up to the age of 42 years. CHD patients had more than an 8× higher risk (incidence rate ratio, 8.23; 95% confidence interval, 6–11.2) of developing ICH and almost an 8× higher risk of developing SAH (incidence rate ratio, 7.64; 95% confidence interval, 5.41–10.7) compared with controls. The absolute risk of ICH and SAH was low, with incidence rates of 1.18 and 0.96 cases per 10 000 person-years, respectively. Patients with severe nonconotruncal defects (incidence rate ratio, 16.5; 95% confidence interval, 5.63–51.2) or coarctation of the aorta (incidence rate ratio, 17.3; 95% confidence interval, 6.63–51.8) had the highest relative risk of developing hemorrhagic stroke, with incidence rates of 3.22 and 2.79 cases per 10 000 person-years, respectively. Conclusions— The relative risk of hemorrhagic stroke among children and young adults with CHD was almost 8× higher than that of matched controls from the general population, although the absolute risk was low. The highest risk of ICH and SAH occurred in patients with severe nonconotruncal defects and coarctation of the aorta.

Long-term trends in the prevalence of patients hospitalized with ischemic stroke from 1995 to 2010 in Sweden

Objective The prevalence of stroke is expected to increase partly because of prolonged life expectancy in the general population. The objective of this study was to investigate trends in the prevalence of patients hospitalized with ischemic stroke (IS) in Sweden from 1995–2010. Methods The Swedish inpatient and cause-specific death registries were used to estimate the absolute numbers and prevalence of patients who were hospitalized with and survived an IS from 1995–2010. Results The overall number of IS increased from 129,418 in 1995 to 148,778 in 2010. In 1995, the prevalence of IS was 189 patients per 10,000 population. An increase in overall prevalence was observed until 2000, and then it remained stable, followed by a decline with an annual percentage change of (APC) -0.8% (95% CI -1.0 to 0.6) and with a final prevalence of 199 patients per 10,000 population in 2010. The prevalence of IS in people aged <45 years increased from 6.4 in 1995 to 7.6 patients per 10,000 population in 2010, with an APC of 2.1% (95% CI 0.9 to 3.4) from 1995–1998 and 0.7% (95% CI 0.6–0.9) from 1998–2010. Among those aged 45–54 years, the prevalence rose through the mid to late 1990s, followed by a slight decrease (APC: -0.7%, 95% CI-1.1 to -0.4) until 2006 and then remained stable with a prevalence of 43.8 patients per 10,000 population in 2010. Among ≥85 years, there was a minor decrease (APC: -0.3%, 95% CI -0.5 to -0.1) in overall prevalence after 2002 from 1481 to 1453 patients per 10,000 population in 2010. Conclusion The overall prevalence of IS increased until 2000, but then remained stable followed by a slight decline. However, the prevalence of IS in the young increased through the study period. The absolute number of IS survivors has markedly increased, mainly because of demographic changes.