Background

In recent years, research on the association between physical environments and cardiovascular disease outcomes has gained momentum with growing attention being paid to Geographic Information Systems (GIS). This nationwide study is the first to examine the effect of neighbourhood physical environments on individual-level stroke, using GIS-based measures of neighbourhood availability of potentially health-damaging (fast food restaurants and pubs/bars) and health-promoting (physical activity and healthcare) resources.

Methods

The study population comprised a nationwide sample of 2,115,974 men and 2,193,700 women aged 35–80 years who were followed between 1 December 2005 and 31 December 2007 in Sweden. Totally 42,270 first-ever strokes (both morbidity and mortality) were identified. Multilevel logistic regression models were used to estimate the association between neighbourhood availability of four different resources (fast food restaurants, pubs/bars, physical activity and healthcare) and individual-level stroke.

Principal Findings

There were significant associations between neighbourhood availability of the four types of neighbourhood resources and individual-level stroke. The significant odds ratios varied between 1.06 and 1.12 for men and 1.07 and 1.24 for women. After adjustment for age, income, and neighbourhood-level deprivation, the increased odds remained statistically significant for neighbourhood availability of fast food restaurants in both men and women.

Conclusions

Specific neighbourhood availability of resources were associated with individual-level stroke but most of these associations were explained by individual-level sociodemographic factors and neighbourhood-level deprivation.

Background

Cancer of unknown primary site (CUP) is considered an aggressive metastatic disease but whether the prognosis differs from metastatic cancers of known primary site is not known. Such data may give insight into the biology of CUP and the metastatic process in general.

Methods

6,745 cancer patients, with primary metastatic cancer at diagnosis, were identified from the Swedish Cancer Registry, and were compared with 2,881 patients with CUP. Patients were diagnosed and died between 2002 and 2008. The influence of the primary site, known or unknown, on survival in patients with metastases at specific locations was investigated. Hazard ratios (HRs) of death were estimated for several sites of metastasis, where patients with known primary sites were compared with CUP patients.

Results

Overall, patients with metastatic cancers with known primary sites had decreased hazards of death compared to CUP patients (HR = 0.69 [95% CI = 0.66–0.72]). The exceptions were cancer of the pancreas (1.71 [1.54–1.90]), liver (1.58 [1.36–1.85]), and stomach (1.16 [1.02–1.31]). For individual metastatic sites, patients with liver or bone metastases of known origin had better survival than those with CUP of the liver and bone. Patients with liver metastases of pancreatic origin had an increased risk of death compared with patients with CUP of the liver (1.25 [1.06–1.46]). The median survival time of CUP patients was three months.

Conclusions

Patients with CUP have poorer survival than patients with known primaries, except those with brain and respiratory system metastases. Of CUP sites, liver metastases had the worst prognosis. Survival in CUP was comparable to that in metastatic lung cancer. The aggressive behavior of CUP may be due to initial immunosuppression and immunoediting which may allow accumulation of mutations. Upon escape from the suppressed state an unstoppable tumor spread ensues. These novel data on the epidemiology of the metastatic process at the population level demonstrated large survival differences in organ defined metastases depending on the original cancer.

Context

Prior research suggests that drug abuse (DA) is strongly influenced by both genetic and familial environmental factors. No large-scale adoption study has previously attempted to verify and integrate these findings.

Objective

To determine how genetic and environmental factors contribute to the risk for DA.

Design

Follow-up in 9 public databases (1961–2009) of adopted children and their biological and adoptive relatives.

Setting

Sweden.

Participants

The study included 18 115 adopted children born between 1950 and 1993; 78 079 biological parents and siblings; and 51 208 adoptive parents and siblings.

Main Outcome Measures

Drug abuse recorded in medical, legal, or pharmacy registry records.

Results

Risk for DA was significantly elevated in the adopted offspring of biological parents with DA (odds ratio, 2.09; 95% CI, 1.66–2.62), in biological full and half siblings of adopted children with DA (odds ratio, 1.84; 95% CI, 1.28–2.64; and odds ratio, 1.41; 95% CI, 1.19–1.67, respectively), and in adoptive siblings of adopted children with DA (odds ratio, 1.95; 95% CI, 1.43–2.65). A genetic risk index (including biological parental or sibling history of DA, criminal activity, and psychiatric or alcohol problems) and an environmental risk index (including adoptive parental history of divorce, death, criminal activity, and alcohol problems, as well as an adoptive sibling history of DA and psychiatric or alcohol problems) both strongly predicted the risk for DA. Including both indices along with sex and age at adoption in a predictive model revealed a significant positive interaction between the genetic and environmental risk indices.

Conclusions

Drug abuse is an etiologically complex syndrome strongly influenced by a diverse set of genetic risk factors reflecting a specific liability to DA, by a vulnerability to other externalizing disorders, and by a range of environmental factors reflecting marital instability, as well as psychopathology and criminal behavior in the adoptive home. Adverse environmental effects on DA are more pathogenic in individuals with high levels of genetic risk. These results should be interpreted in the context of limitations of the diagnosis of DA from registries.

Purpose

Previous studies of neighborhood deprivation and mental disorders have yielded mixed results, possibly because they were based on different substrata of the population. We conducted a national multilevel study to determine whether neighborhood deprivation is independently associated with psychiatric medication prescription in a national population.

Methods

Nationwide outpatient and inpatient psychiatric medication data were analyzed for all Swedish adults (N=6,998,075) after 2.5 years of follow-up. Multilevel logistic regression was used to estimate the association between neighborhood deprivation (index of education, income, unemployment, and welfare assistance) and prescription of psychiatric medications (antipsychotics, antidepressants, anxiolytics, or hypnotics/sedatives), after adjusting for broadly measured individual-level sociodemographic characteristics.

Results

For each psychiatric medication class, a monotonic trend of increasing prescription was observed by increasing level of neighborhood deprivation. The strongest associations were found for antipsychotics and anxiolytics, with adjusted odds ratios of 1.40 (95% CI, 1.36–1.44) and 1.24 (95% CI, 1.22–1.27), respectively, comparing the highest- to the lowest-deprivation neighborhood quintiles.

Conclusions

These findings suggest that neighborhood deprivation is associated with psychiatric medication prescription independent of individual-level sociodemographic characteristics. Further research is needed to elucidate the mechanisms by which neighborhood deprivation may affect mental health and to identify the most susceptible groups in the population.

Background

Although the heritability of atrial fibrillation (AF) has been determined, the relevance of family history of AF for the likelihood of recurrent hospitalization for AF is unknown. The aim of this nationwide study was to determine whether family history of AF is a risk factor of recurrent hospitalization for lone AF (LAF), i.e., AF with unknown etiology. The familial risk for first time LAF hospitalization was also determined and compared to the risk of recurrent hospitalization for LAF.

Methods

We examined whether family history of AF is a risk factor for recurrent hospitalization for LAF in the whole Swedish population. We linked Multigeneration Register data on individuals aged 0–60 years to Hospital Discharge Register data for the period 1987–2009 to compare LAF recurrent hospitalization risk among individuals with and without parental or sibling history of AF. We calculated hazard ratios (HRs) to determine the familial HR of recurrent hospitalization for LAF. Odds ratios (OR) were calculated for familial risk of first time LAF hospitalization.

Results

The risk of recurrent LAF hospitalization was 1.23 (95% CI 1.17-1.30) for individuals with affected parents compared to 1.30 (95% CI 1.22-1.38) for those with affected siblings. After 10 years of follow up 50% of those without and 60% of those with family history had recurrent hospitalization for LAF. The risk of recurrent LAF hospitalization in individuals with two affected parents was 1.65 (95% CI 1.44-1.90). There was an interaction between age and family history, with family history having a weaker effect on LAF hospitalization risk in older age groups. The OR for first time LAF hospitalization was 2.08 (95% CI 2.02-2.15) for offspring with affected parents and 3.23 (95% CI 3.08-3.39) for individuals with affected siblings.

Conclusions

Family history of AF is a novel risk factor for recurrent LAF hospitalization. The higher recurrence hospitalization risk in multiplex families and younger individuals suggests a genetic contribution. However, the familial risk for recurrent LAF hospitalization was much lower than the risk for first time LAF hospitalization, suggesting that familial and possibly genetic factors are more important for first time LAF hospitalization than recurrent LAF hospitalization.

Background

Amyloidosis is a heterogeneous disease caused by deposition of amyloid fibrils in organs and thereby interfering with physiological functions. Hardly any incidence data are available and most survival data are limited to specialist clinics.

Methods

Amyloidosis patients were identified from the Swedish Hospital Discharge and Outpatients Registers from years 2001 through 2008.

Results

The incidence of non-hereditary amyloidosis in 949 patients was 8.29 per million person-years and the diagnostic age with the highest incidence was over 65 years. Secondary systemic amyloidosis showed an incidence of 1 per million and a female excess and the largest number of subsequent rheumatoid arthritis deaths; the median survival was 4 years. However, as rheumatoid arthritis deaths also occurred in other diagnostic subtypes, the incidence of secondary systemic amyloidosis was likely to be about 2.0 per million. The median survival of patients with organ-limited amyloidosis was 6 years. Most myeloma deaths occurred in patients diagnosed with unspecified or ‘other’ amyloidosis. These subtypes probably accounted for most of immunoglobulin light chain (AL) amyloidosis cases; the median survival time was 3 years.

Conclusions

The present diagnostic categorization cannot single out AL amyloidosis in the Swedish discharge data but, by extrapolation from myeloma cases, an incidence of 3.2 per million could be ascribed to AL amyloidosis. Similarly, based on rheumatoid arthritis death rates, an incidence of 2.0 could be ascribed to secondary systemic amyloidosis.

Aim.

To examine whether mothers' and fathers' levels of perceived relationship discord at childbirth were associated with postpartum depressive symptoms when the child was 3 months old. Another aim was to examine parents' levels of self-reported depressive symptoms. The hypothesis was that parents with high levels of perceived relationship discord have higher levels of postpartum depressive symptoms than parents with low levels of perceived relationship discord.

Method.

One week after childbirth, 305 couples' perceived level of relationship discord was measured using the Dyadic Consensus Subscale (DCS) of the Dyadic Adjustment Scale (DAS). At 3 months postpartum, the same couples answered the Edinburgh Postnatal Depression Scale (EPDS) questionnaire. The relations between perceived level of relationship discord and postpartum depressive symptoms were analysed using standard non-parametric statistical methods.

Results.

The mothers and fathers partly differed regarding which areas of their relationship they perceived that they disagreed with their partners about. Furthermore, 16.5% of the mothers and 8.7% of the fathers reported postpartum depressive symptoms, and there was a moderate level of correlation between the DCS and EPDS scores.

Conclusion.

These results may be useful for professionals in antenatal care and child health centres as well as for family caregivers who need to be aware that mothers and fathers may have different views on relationship discord and of the high level of depressive symptoms in recent parents. Further research is needed to examine perceived relationship discord and the development of depressive symptoms postpartum over a longer term.

Background

Neighborhood walkability has been associated with physical activity in several studies. However, as environmental correlates of physical activity may be context specific, walkability parameters need to be investigated separately in various countries and contexts. Furthermore, the mechanisms by which walkability affects physical activity have been less investigated. Based on previous research, we hypothesized that vehicle ownership is a potential mediator. We investigated the associations between walkability parameters and physical activity, and the mediating and moderating effects of vehicle ownership on these associations in a large sample of Swedish adults.

Methods

Residential density, street connectivity and land use mix were assessed within polygon-based network buffers (using Geographic Information Systems) for 2,178 men and women. Time spent in moderate to vigorous physical activity was assessed by accelerometers, and walking and cycling for transportation were assessed by the International Physical Activity Questionnaire. Associations were examined by linear regression and adjusted for socio-demographic characteristics. The product of coefficients approach was used to investigate the mediating effect of vehicle ownership.

Results

Residential density and land use mix, but not street connectivity, were significantly associated with time spent in moderate to vigorous physical activity and walking for transportation. Cycling for transportation was not associated with any of the walkability parameters. Vehicle ownership mediated a significant proportion of the association between the walkability parameters and physical activity outcomes. For residential density, vehicle ownership mediated 25% of the association with moderate to vigorous physical activity and 20% of the association with the amount of walking for transportation. For land use mix, the corresponding proportions were 34% and 14%. Vehicle ownership did not moderate any of the associations between the walkability parameters and physical activity outcomes.

Conclusions

Residential density and land use mix were associated with time spent in moderate to vigorous physical activity and walking for transportation. Vehicle ownership was a mediator but not a moderator of these associations. The present findings may be useful for policy makers and city planners when designing neighborhoods that promote physical activity.

Objective:

To determine whether preterm birth is associated with epilepsy in a national cohort of adults aged 25–37 years.

Methods:

We conducted a national cohort study of 630,090 infants born in Sweden from 1973 through 1979, including 27,953 born preterm (<37 weeks), followed from 2005 to 2009 for 1) hospitalization for epilepsy and 2) outpatient and inpatient prescription of antiepileptic drugs. Epilepsy diagnoses and medication data were obtained from all hospitals and pharmacies throughout Sweden.

Results:

We found a strong association between preterm birth and epilepsy that increased by earlier gestational age. After adjusting for fetal growth and potential confounders, odds ratios for hospitalization for epilepsy were 4.98 (95%confidence interval [CI] 2.87–8.62) for those born at 23–31 weeks, 1.98 (95% CI 1.26–3.13) for those born at 32–34 weeks, and 1.76 (95% CI 1.30–2.38) for those born at 35–36 weeks, relative to those born full-term (37–42 weeks). A similar but slightly weaker trend was observed for the association between preterm birth and antiepileptic drug prescription. These associations persisted after excluding individuals with cerebral palsy, inflammatory diseases of the CNS, cerebrovascular disease, and brain tumors.

Conclusions:

These findings suggest that preterm birth, including late preterm birth, is strongly associated with epilepsy in Swedish adults aged 25–37 years. This association was independent of fetal growth and was not mediated by cerebral palsy or other comorbidities.

Background

Patients with many types of autoimmune diseases (AIDs) are at an increased risk of cancer, which may depend on underlying dysregulation of the immune system or treatment. We systematically analyzed myeloma risk and survival in patients diagnosed with 33 different AIDs.

Methods

Data on patients with AIDs were retrieved from the Swedish Hospital Discharge Register and were linked to myeloma diagnoses from the Cancer Registry. Standardized incidence ratios (SIR) and hazard ratios (HRs) were calculated for subsequent myeloma between 1964 and 2008.

Results

Among patients with the 33 AIDs analyzed, 457 cases of myeloma were diagnosed. The overall SIR for myeloma was 1.12 and the overall HR was 0.92 and non-significant. SIRs for myeloma were significantly increased after ankylosing spondylitis (2.02) and systemic sclerosis (2.63). Only the HR for myeloma after rheumatic fever (5.27) was significantly increased. The SIR for myeloma before age 60 years was 1.45; the SIR for myeloma was only increased in the period 1964–1990 (1.31) and not later (1.04). Only the SIR for myeloma after ankylosing spondylitis was increased in the period 1991–2008 (2.09); the HRs for myeloma were increased after polymyositis/dermatomyositis (6.44) and rheumatic fever (4.43) but there were only three deaths of myeloma after these AIDs.

Conclusions

The present data showed an increase in myeloma SIR after two AIDs, ankylosing spondylitis and systemic sclerosis, and in HR after rheumatic fever. The overall myeloma risk after any AID was no longer increased in the latter follow-up period of 1991 through 2008.

Background

Few studies have investigated sexual dysfunction in immigrant patients with type 2 diabetes in Sweden. The aim of this study was to examine the association between ethnicity and sexual dysfunction and to analyze if this association remains after adjusting for explanatory variables including age, marital status, HbA1c, triglycerides, and hypertension. This cross-sectional study was conducted at four primary health care centers in the Swedish town of Södertälje. A total of 354 persons with type 2 diabetes (173 Assyrians/Syrians and 181 Swedish-born patients) participated in the survey. The main outcome measure was the self-reported presence of sexual dysfunction based on two questions, one regarding loss of ability to have sexual intercourse and the other loss of sexual desire. Response rates were 78% and 86%, respectively.

Findings

The total prevalence of loss of ability to have intercourse was 29.5%. In the multivariate models, the odds of loss of ability to have intercourse was significantly higher in the oldest age group (OR = 5.80; 95% CI, 2.33–14.40), in men (OR = 3.33; 95% CI, 1.33–8.30), and in unmarried individuals (OR = 2.40; 95% CI, 1.02–5.70). The odds of reporting loss of sexual desire was higher in Assyrians/Syrians than in Swedish-born patients and increased from 2.00 in the age- and gender-adjusted model to 2.70 in the fully adjusted model when all confounders were taken into account.

Conclusions

Sexual dysfunction appears to be more common in Assyrians/Syrians than in Swedish-born patients. Health care workers should actively ask about sexual function in their patients with type 2 diabetes.

Background

Exercise facilities may have the potential to promote physical activity among residents, and to support an active lifestyle throughout the year. We investigated the association between objectively assessed availability of exercise facilities and objectively assessed physical activity outcomes, and whether time of year had a modifying effect on these associations.

Methods

A total of 2,037 adults (55% females) wore an accelerometer for seven days. Time spent in moderate to vigorous physical activity (minutes per day) and meeting the physical activity recommendations (yes/no) were used as outcome variables. Availability of exercise facilities was measured within 1,000-meter line-based road network buffers around participants’ residential addresses using Geographic Information Systems. Socio-demographic variables and time of year were included as covariates in the analyses.

Results

Participants with ≥4 exercise facilities within their buffer zones spent 5.4 (confidence interval (CI) = 2.3-8.5) more minutes in moderate to vigorous physical activity per day, and had 69% higher odds (OR = 1.69; CI = 1.39-2.05) of meeting the physical activity recommendations, compared to those with no exercise facilities within their buffer zones. Time of year had no modifying effect on these associations.

Conclusions

Our results show that objective availability of exercise facilities was associated with accelerometer-assessed time spent in moderate to vigorous physical activity and the odds of meeting the recommended levels of physical activity. Neighborhoods may be a logical and potentially significant venue for policy interventions aimed at increasing physical activity in the overall population.

SUMMARY

Objective

Previous studies suggest that low birth weight is associated with thyroid autoimmunity and hypothyroidism in later life, but the potential effect of preterm birth, independent of fetal growth, is unknown. Our objective was to determine whether preterm birth is independently associated with medically treated hypothyroidism in young adulthood.

Design/Participants

National cohort study of 629,806 individuals born in Sweden from 1973 through 1979, including 27,935 born preterm (<37 weeks).

Measurements

Thyroid hormone prescription during 2005–2009 (ages 25.5–37.0 years), obtained from all outpatient and inpatient pharmacies throughout Sweden.

Results

Preterm birth was associated with increased relative odds of thyroid hormone prescription in young adulthood, after adjusting for fetal growth and other potential confounders. This association appeared stronger among twins than singletons (P=0.04 for the interaction). Twins had increased relative odds across the full range of preterm gestational ages, whereas singletons had increased relative odds only if born very preterm (23–31 weeks). Among twins and singletons, respectively, adjusted odds ratios for individuals born preterm (<37 weeks) were 1.54 (95% CI, 1.11–2.14) and 1.08 (95% CI, 0.98–1.19), and for individuals born very preterm (23–31 weeks) were 2.62 (95% CI, 1.30–5.27) and 1.59 (95% CI, 1.18–2.14), relative to full-term births.

Conclusions

This national cohort study suggests that preterm birth is associated with an increased risk of medically treated hypothyroidism in young adulthood. This association was independent of fetal growth and appeared stronger among twins than singletons. Additional studies are needed to confirm these new findings in other populations and to elucidate the mechanisms.

Venous thromboembolism (VTE) is major health problem and is sometimes complicated by lethal pulmonary embolism (PE). Disturbances of the coagulation and anticoagulation systems are important risk factors for VTE. Comparative studies suggest that coagulation and innate immunity have a shared evolutionary origin. It is therefore unsurprising that the immune and coagulation systems are linked, with many molecular components being important for both systems. Systemic inflammation modulates thrombotic responses by suppressing fibrinolysis, upregulating procoagulant, and downregulating anticoagulants, and autoimmune disorders such as systemic lupus erythematosus (SLE), inflammatory bowel disease (IBD), and Behçet’s syndrome have been linked to an increased risk of VTE. Recent reports have further shown that a majority of autoimmune and immune-mediated disorders are linked to an increased risk of venous thrombosis, PE, or VTE. For instance, a Swedish nationwide study found that the risk of PE was increased in the first year after hospitalization for 33 different autoimmune disorders. Especially high risks were noted for several autoimmune diseases such as immune thrombocytopenic purpura, polyarteritis nodosa, polymyositis/dermatomyositis, ulcerative colitis, and SLE. Another study from England, also based on hospitalization data, found that immune-mediated disorders were associated with an increased risk of VTE compared with other medical causes of hospitalization. Multiple mechanisms may operate and disease-specific factors, such as cardiolipin antibodies, have been identified. However, inflammation by itself appears to change the hemostatic balance in a thrombogenic direction. Recent epidemiological studies, together with previous experimental and clinical studies, indicate that autoimmune disorders should not only be viewed as inflammatory disorders, but also hypercoagulable disorders. Research to identify thrombotic risk factors, elucidate the mechanisms involved, and investigate prophylactic regiments is needed. The present review describes the epidemiological, clinical, and experimental evidence for the connection between VTE and autoimmune and immune-mediated disorders.

Background

Acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) are common early-onset malignancies. Their causes are largely unknown but infectious etiology has been implicated. Type 1 diabetes (T1D) is an autoimmune disease for which infectious triggers of disease onset have been sought and increasing pointing to enteroviruses. Based on our previous results on co-morbidity between leukemia and T1D, we updated the Swedish dataset and focused on early onset leukemias in patients who had been hospitalized for T1D, comparing to those not hospitalized for T1D.

Methods and Findings

Standardized incidence ratios (SIRs) were calculated for leukemia in 24,052 patients hospitalized for T1D covering years 1964 through 2008. T1D patients were included if hospitalized before age 21 years. Practically all Swedish children and adolescents with T1D are hospitalized at the start of insulin treatment. SIR for ALL was 8.30 (N = 18, 95% confidence interval 4.91–13.14) when diagnosed at age 10 to 20 years after hospitalization for T1D and it was 3.51 (13, 1.86–6.02) before hospitalization for T1D. The SIR for ALL was 19.85 (N = 33, 13.74–27.76) and that for AML was 25.28 (8, 10.80–50.06) when the leukemias were diagnosed within the year of T1D hospitalization. The SIRs increased to 38.97 (26, 25.43–57.18) and 40.11 (8, 17.13–79.42) when T1D was diagnosed between ages 10 to 20 years. No consistent time-dependent changes were found in leukemia risk.

Conclusion

A shared infectious etiology could be a plausible explanation to the observed co-morbidity. Other possible contributing factors could be insulin therapy or T1D related metabolic disturbances.

Background

The present study protocol describes the trial design of a primary care intervention cohort study, which examines whether an extended, multi-professional physical activity referral (PAR) intervention is more effective in enhancing and maintaining self-reported physical activity than physical activity prescription in usual care. The study targets patients with newly diagnosed hypertension and/or type 2 diabetes. Secondary outcomes include: need of pharmacological therapy; blood pressure/plasma glucose; physical fitness and anthropometric variables; mental health; health related quality of life; and cost-effectiveness.

Methods/Design

The study is designed as a long-term intervention. Three primary care centres are involved in the study, each constituting one of three treatment groups: 1) Intervention group (IG): multi-professional team intervention with PAR, 2) Control group A (CA): physical activity prescription in usual care and 3) Control group B: treatment as usual (retrospective data collection). The intervention is based on self-determination theory and follows the principles of motivational interviewing. The primary outcome, physical activity, is measured with the International Physical Activity Questionnaire (IPAQ) and expressed as metabolic equivalent of task (MET)-minutes per week. Physical fitness is estimated with the 6-minute walk test in IG only. Variables such as health behaviours; health-related quality of life; motivation to change; mental health; demographics and socioeconomic characteristics are assessed with an electronic study questionnaire that submits all data to a patient database, which automatically provides feed-back to the health-care providers on the patients’ health status. Cost-effectiveness of the intervention is evaluated continuously and the intermediate outcomes of the intervention are extrapolated by economic modelling.

Discussions

By helping patients to overcome practical, social and cultural obstacles and increase their internal motivation for physical activity we aim to improve their physical health in a long-term perspective. The targeted patients belong to a patient category that is supposed to benefit from increased physical activity in terms of improved physiological values, mental status and quality of life, decreased risk of complications and maybe a decreased need of medication.

Background

Certain immune-mediated diseases (IMDs) have been associated with increased risk for cardiovascular disorders. The aim of the present study was to examine whether there is an association between 32 different IMDs and first hospitalization for ischemic or hemorrhagic stroke.

Methods

All individuals in Sweden hospitalized with a main diagnosis of IMD (without previous or coexisting stroke), between January 1, 1987 and December 31, 2008 (n = 216,291), were followed for first hospitalization for ischemic or hemorrhagic stroke. The reference population was the total population of Sweden. Adjusted standardized incidence ratios (SIRs) for ischemic and hemorrhagic stroke were calculated.

Results

Totally 20 and 15 of the 32 IMDs studied, respectively, were associated with an increased risk of ischemic and hemorrhagic stroke during the follow-up. The overall risks of ischemic and hemorrhagic stroke during the first year after hospitalization for IMD were 2.02 (95% CI 1.90–2.14) and 2.65 (95% CI 2.27–3.08), respectively. The overall risk of ischemic or hemorrhagic stroke decreased over time, to 1.50 (95% CI 1.46–1.55) and 1.83 (95% CI 1.69–1.98), respectively, after 1–5 years, and 1.29 (95% CI 1.23–1.35) and 1.47 (95% CI 1.31–1.65), respectively, after 10+ years. The risk of hemorrhagic stroke was ≥2 during the first year after hospitalization for seven IMDs: ankylosing spondylitis (SIR = 8.11), immune thrombocytopenic purpura (SIR = 8.60), polymyalgia rheumatica (SIR = 2.06), psoriasis (SIR = 2.88), rheumatoid arthritis (SIR = 3.27), systemic lupus erythematosus (SIR = 8.65), and Wegener´s granulomatosis (SIR = 5.83). The risk of ischemic stroke was ≥2 during the first year after hospitalization for twelve IMDs: Addison’s disease (SIR = 2.71), Crohn´s disease (SIR = 2.15), Grave´s disease (SIR = 2.15), Hashimoto´s thyroiditis (SIR = 2.99), immune thrombocytopenic purpura (SIR = 2.35), multiple sclerosis (SIR = 3.05), polymyositis/dermatomyositis (SIR = 3.46), rheumatic fever (SIR = 3.91), rheumatoid arthritis (SIR = 2.08), Sjögren’s syndrome (SIR = 2.57), systemic lupus erythematosus (SIR = 2.21), and ulcerative colitis (SIR = 2.15).

Conclusions

Hospitalization for many IMDs is associated with increased risk of ischemic or hemorrhagic stroke. The findings suggest that several IMDs are linked to cerebrovascular disease.

Background

Previous studies of the association between gestational age or birth weight and allergic rhinitis in later life have had various limitations, including inability to estimate risk among individuals born extremely preterm and/or to examine specific contributions of gestational age and fetal growth.

Objective

To determine whether gestational age at birth, independent of fetal growth, is associated with allergic rhinitis medication prescription in a national cohort of young adults.

Methods

We conducted a national cohort study of 630,090 infants born in Sweden from 1973 through 1979 (including 27,953 born preterm, <37 weeks), followed for prescription of nasal corticosteroids and oral antihistamines in 2005-2009 (ages 25.5-37.0 years). Medication data were obtained from all outpatient and inpatient pharmacies throughout Sweden.

Results

The overall prevalence of nasal corticosteroid and oral antihistamine prescription was 16.3% and 16.8%, respectively, similar to the reported prevalence of allergic rhinitis in this population. Low gestational age at birth was associated with a decreased risk of nasal corticosteroid and/or oral antihistamine prescription in young adulthood, after adjusting for fetal growth and other potential confounders. For individuals born extremely preterm (23-28 weeks), adjusted odds ratios were 0.70 (95% CI, 0.51-0.96) for nasal corticosteroid prescription, and 0.45 (95% CI, 0.27-0.76) for both nasal corticosteroid and oral antihistamine prescription, relative to full-term births.

Conclusion

These findings suggest that low gestational age at birth, independent of fetal growth, is associated with a decreased risk of allergic rhinitis in young adulthood, possibly due to a protective effect of earlier exposure to pathogens.

OBJECTIVE

Previous studies have suggested that preterm birth is associated with diabetes later in life. These studies have shown inconsistent results for late preterm births and have had various limitations, including the inability to evaluate diabetic outpatients or to estimate risk across the full range of gestational ages. Our objective was to determine whether preterm birth is associated with diabetes medication prescription in a national cohort of young adults.

RESEARCH DESIGN AND METHODS

This was a national cohort study of 630,090 infants born in Sweden from 1973 through 1979 (including 27,953 born preterm, gestational age <37 weeks), followed for diabetes medication prescription in 2005–2009 (ages 25.5–37.0 years). Medication data were obtained from all outpatient and inpatient pharmacies throughout Sweden.

RESULTS

Individuals born preterm, including those born late preterm (gestational age 35–36 weeks), had modestly increased odds ratios (ORs) for diabetes medication prescription relative to those born full term, after adjusting for fetal growth and other potential confounders. Insulin and/or oral diabetes medications were prescribed to 1.5% of individuals born preterm compared with 1.2% of those born full term (adjusted OR 1.13 [95% CI 1.02–1.26]). Insulin without oral diabetes medications was prescribed to 1.0% of individuals born preterm compared with 0.8% of those born full term (1.22 [1.08–1.39]).

CONCLUSIONS

Preterm birth, including late preterm birth, is associated with a modestly increased risk of diabetes in young Swedish adults. These findings have important public health implications given the increasing number of preterm births and the large disease burden of diabetes, particularly when diagnosed in young adulthood.

Previous studies have reported an association between preterm birth and elevated blood pressure in adolescence and young adulthood. These studies were based on single-day blood pressure measurements and had limited ability to estimate risk of hypertension measured over a longer period and across the full range of gestational ages. The authors conducted a national cohort study of all infants born in Sweden from 1973 through 1979 (n = 636,552), including 28,220 born preterm (<37 weeks), followed to ages 25.5–37.0 years to determine whether individuals born preterm were more likely to be prescribed antihypertensive medications in 2005–2009 than those born full term. Antihypertensive medication data were obtained from all outpatient and inpatient pharmacies throughout Sweden. Young adults who were born preterm had an increased relative rate of antihypertensive medication prescription that increased monotonically by earlier gestational age and that was independent of fetal growth. The adjusted odds ratio for ≥1 antihypertensive medications/year ranged from 1.25 (95% confidence interval: 1.12, 1.39) for those born near term (35–36 weeks) to 2.51 (95% confidence interval: 1.11, 5.68) for those born extremely preterm (23–27 weeks) relative to those born full term. These findings suggest that preterm birth is strongly associated with hypertension in young adulthood, including an increased risk among those born near term.

OBJECTIVE:

Preterm birth is associated with asthma-like symptoms in childhood and possibly in adolescence, but the longer-term risk of asthma is unknown and increasingly relevant as larger numbers of these individuals enter adulthood. Our objective was to evaluate whether those who were born preterm are more likely to be prescribed asthma medications in young adulthood than those who were born term.

PATIENTS AND METHODS:

We conducted a national cohort study of all singleton infants born in Sweden from 1973 through 1979 (n = 622 616), followed to ages 25.5 to 35.0 years to determine whether asthma medications were prescribed in 2005–2007. Asthma medication data were obtained from all outpatient and inpatient pharmacies throughout Sweden. To improve the positive predictive value for asthma, the outcome was defined as prescription of (1) both a β-2 agonist inhalant and a glucocorticoid inhalant or (2) a combination inhalant containing a β-2 agonist and other drugs for obstructive airway diseases.

RESULTS:

Young adults who were born extremely preterm (23–27 weeks' gestation) were 2.4 times more likely (adjusted 95% CI: 1.41–4.06) to be prescribed asthma medications than those who were born term. No association was found between later preterm birth (28–32 or 33–36 weeks' gestation) and asthma medications in young adulthood.

CONCLUSIONS:

This is the first study with sufficient statistical power to evaluate the risk of asthma beyond adolescence in individuals who were born extremely preterm. The results suggest that extreme preterm birth (23–27 weeks' gestation), but not later preterm birth, is associated with an increased risk of asthma at least into young adulthood.

Background

Certain immune-mediated diseases (IMDs), such as rheumatoid arthritis and systemic lupus erythematosus, have been linked to cardiovascular disorders. We examined whether there is an association between 32 different IMDs and risk of subsequent hospitalization for coronary heart disease (CHD) related to coronary atherosclerosis in a nationwide follow up study in Sweden.

Methods and Findings

All individuals in Sweden hospitalized with a main diagnosis of an IMD (n = 336,479) without previous or coexisting CHD, between January 1, 1964 and December 31 2008, were followed for first hospitalization for CHD. The reference population was the total population of Sweden. Standardized incidence ratios (SIRs) for CHD were calculated. Overall risk of CHD during the first year after hospitalization for an IMD was 2.92 (95% CI 2.84–2.99). Twenty-seven of the 32 IMDs studied were associated with an increased risk of CHD during the first year after hospitalization. The overall risk of CHD decreased over time, from 1.75 after 1–5 years (95% CI 1.73–1.78), to 1.43 after 5–10 years (95% CI 1.41–1.46) and 1.28 after 10+ years (95% CI 1.26–1.30). Females generally had higher SIRs than males. The IMDs for which the SIRs of CDH were highest during the first year after hospitalization included chorea minor 6.98 (95% CI 1.32–20.65), systemic lupus erythematosus 4.94 (95% CI 4.15–5.83), rheumatic fever 4.65 (95% CI 3.53–6.01), Hashimoto's thyroiditis 4.30 (95% CI 3.87–4.75), polymyositis/dermatomyositis 3.81 (95% CI 2.62–5.35), polyarteritis nodosa 3.81 (95% CI 2.72–5.19), rheumatoid arthritis 3.72 (95% CI 3.56–3.88), systemic sclerosis 3.44 (95% CI 2.86–4.09), primary biliary cirrhosis 3.32 (95% CI 2.34–4.58), and autoimmune hemolytic anemia 3.17 (95% CI 2.16–4.47).

Conclusions

Most IMDs are associated with increased risk of CHD in the first year after hospital admission. Our findings suggest that many hospitalized IMDs are tightly linked to coronary atherosclerosis.

Background Recent studies suggest an increased risk of adverse mental health outcomes among young adults who were born preterm. These studies have been based mainly on hospital data, thus missing large numbers of mental health problems that do not require inpatient treatment. We used national outpatient and inpatient pharmacy data to evaluate whether individuals who were born preterm were more likely to be prescribed psychiatric medications during young adulthood than individuals who were born full term.

Methods A national cohort of all infants born in Sweden from 1973 through 1979 [N = 635 933, including 28 799 who were born preterm (<37 weeks)] was followed to ages 25.5–34.0 years to determine whether psychotropic medications (antidepressants, antipsychotics, anxiolytics, hypnotics/sedatives and/or psychostimulants) were prescribed in 2005–06.

Results A trend of increasing rate of prescriptions for antipsychotics, antidepressants and hypnotics/sedatives in young adulthood was observed by earlier gestational age at birth. Young adults who were extremely preterm at birth (23–27 weeks) were 3.1 times more likely to be prescribed antipsychotics [95% confidence interval (CI) 1.66–5.93], 1.8 times more likely to be prescribed antidepressants (95% CI 1.26–2.64) and 1.8 times more likely to be prescribed hypnotics/sedatives (95% CI 1.15–2.96) than individuals who were full term at birth, after adjusting for potential confounders.

Conclusions This national cohort study, using outpatient and inpatient pharmacy data, suggests that preterm birth has important independent effects on mental health that extend at least into young adulthood.

The present study assessed subsequent cancer risks in type 2 diabetes patients first hospitalized for this disease at age >39 years. Twenty-four cancer types showed an elevated risk when follow-up was started after the last hospitalization for type 2 diabetes. No additional risk was found in familial diabetics.

Objectives.

Cancer and type 2 diabetes (T2D) are two common diseases that may share risk factors. We aimed at determining subsequent cancer risks in patients hospitalized for T2D in Sweden.

Methods.

T2D patients were obtained from the nationwide Hospital Discharge Register; cancers were recorded from the Swedish Cancer Registry. Standardized incidence ratios (SIRs) were calculated for cancer following last hospitalization for T2D. The comparison group was the general Swedish population.

Results.

The number of hospitalized T2D patients from 1964 to 2007 was 125,126, of whom 26,641 had an affected family member. Altogether 24 cancers showed an elevated risk when follow-up was started after the last hospitalization. The highest SIRs were for pancreatic (6.08) and liver (4.25) cancers. The incidences of these cancers were even elevated when follow-up was started 5 years after the last hospitalization for T2D, with primary liver cancer showing the highest SIR of 4.66. Also increased were the incidences of upper aerodigestive tract, esophageal, colon, rectal, pancreatic, lung, cervical, endometrial, ovarian, and kidney cancers. Prostate cancer showed a lower risk. Familial T2D patients showed no exceptional elevated cancer risks but their prostate cancer and melanoma risks were lower.

Conclusions.

This study, covering approximately one half of Swedish T2D patients, showed an elevated risk for several cancers after hospitalization for T2D, probably indicating the profound metabolic disturbances of the underlying disease. The highest risks were found for liver and pancreatic cancers. No excess cancer risks were observed in familial diabetics. The lower risk for prostate cancer remains intriguing.

Background

During the last decades, global migration has increased and many immigrant groups have a higher prevalence than the native born population of several cardiovascular disease risk factors, including poor dietary habits. However, it is uncertain if dietary habits in immigrant populations reflect dietary habits in their country of origin or if the current diet is a consequence of the migration and possible change of dietary habits. The aim of this study was to examine possible dietary differences between elderly Iranians living in Stockholm, Sweden with elderly Iranians living in Tehran, Iran, taking into account sex, age, marital status, and education.

Methods

Dietary intakes were assessed by semi - quantitative food frequency questionnaire in a cross-sectional study of 121 Iranians living in Stockholm and 52 Iranians living in Tehran, aged 60-80. Differences in dietary habits between the two groups was analysed by bootstrapped regression analyses with 1000 replications.

Results

Iranians living in Sweden had significantly higher intake of protein, total fat, fiber than Iranians living in Iran, but lower consumption of carbohydrates. The observed differences in intake of macronutrients were reflected in consumed amount of all food items, which were higher among Iranians living in Iran with the exception of bread and grain consumption which was lower.

Conclusions

There are general differences in dietary habits between Iranians living in Iran and Iranians living in Sweden. Parts of observed differences in dietary habits may reflect a favourable adoption process to the Swedish dietary habits after migration. Meanwhile other differences are point of concern in light of the high prevalence of overweight, among Iranians living in Sweden and can have unfavourable impact in particular in the context of cardiovascular health.