Federated analyses of multiple data sources in drug safety studies.

PURPOSE: Studies of rare side effects of new drugs with limited exposure may require pooling of multiple data sources. Federated Analyses (FA) allow real-time, interactive, centralized statistical processing of individual-level data from different data sets without transfer of sensitive personal data. METHODS: We review IT-architecture, legal considerations, and statistical methods in FA, based on a Swedish Medical Products Agency methodological development project. RESULTS: In a review of all post-authorisation safety studies assessed by the EMA during 2019, 74% (20/27 studies) reported issues with lack of precision in spite of mean study periods of 9.3 years. FA could potentially improve precision in such studies. Depending on the statistical model, the federated approach can generate identical results to a standard analysis. FA may be particularly attractive for repeated collaborative projects where data is regularly updated. There are also important limitations. Detailed agreements between involved parties are strongly recommended to anticipate potential issues and conflicts, document a shared understanding of the project, and fully comply with legal obligations regarding ethics and data protection. FA do not remove the data harmonisation step, which remains essential and often cumbersome. Reliable support for technical integration with the local server architecture and security solutions is required. Common statistical methods are available, but adaptations may be required. CONCLUSIONS: Federated Analyses require competent and active involvement of all collaborating parties but have the potential to facilitate collaboration across institutional and national borders and improve the precision of postmarketing drug safety studies.

Optimized diagnosis-based comorbidity measures for all-cause mortality prediction in a national population-based ICU population.

BACKGROUND: We aimed to optimize prediction of long-term all-cause mortality of intensive care unit (ICU) patients, using quantitative register-based comorbidity information assessed from hospital discharge diagnoses prior to intensive care treatment. MATERIAL AND METHODS: Adult ICU admissions during 2006 to 2012 in the Swedish intensive care register were followed for at least 4 years. The performance of quantitative comorbidity measures based on the 5-year history of number of hospital admissions, length of stay, and time since latest admission in 36 comorbidity categories was compared in time-to-event analyses with the Charlson comorbidity index (CCI) and the Simplified Acute Physiology Score (SAPS3). RESULTS: During a 7-year period, there were 230,056 ICU admissions and 62,225 deaths among 188,965 unique individuals. The time interval from the most recent hospital stays and total length of stay within each comorbidity category optimized mortality prediction and provided clear separation of risk categories also within strata of age and CCI, with hazard ratios (HRs) comparing lowest to highest quartile ranging from 1.17 (95% CI: 0.52-2.64) to 6.41 (95% CI: 5.19-7.92). Risk separation was also observed within SAPS deciles with HR ranging from 1.07 (95% CI: 0.83-1.38) to 3.58 (95% CI: 2.12-6.03). CONCLUSION: Baseline comorbidity measures that included the time interval from the most recent hospital stay in 36 different comorbidity categories substantially improved long-term mortality prediction after ICU admission compared to the Charlson index and the SAPS score. Trial registration ClinicalTrials.gov ID NCT04109001, date of registration 2019-09-26 retrospectively.

Outcome of PCI with Xience versus other commonly used modern drug eluting stents: A SCAAR report.

OBJECTIVES: To analyze the clinical outcome of percutaneous coronary intervention (PCI) using the Xience drug eluting stent (DES) versus other modern DES. METHODS: This retrospective study based on the Swedish Coronary Angiography and Angioplasty Registry (SCAAR) analyzed the outcome of PCI using Xience versus other commonly used modern DES, 2007 to 2017. The primary outcome measure was a combination of all-cause death, myocardial infarction (MI) and revascularisation with PCI. Angiographical outcome measures were in-stent restenosis (ISR) and stent thrombosis (ST). RESULTS: Rates of the primary outcome measure for Xience and other DES were 31.9% and 28.2% respectively, adjusted hazard ratio (HR) 0.99 (95% CI 0.95-1.03). Crude rates of ISR were 2.9% versus 2.1% over 4.3 and 2.9 years respectively, adjusted HR 0.93 (95% CI 0.81-1.06). Crude rates of ST were 0.9% versus 0.7%, adjusted HR 1.07 (95% CI 0.82-1.39). Results were consistent in all sensitivity analyses. CONCLUSIONS: This nationally complete, real-world study confirms that Xience is a safe and effective DES with low-event rates of ISR and ST. Compared with a control group containing a large proportion of thinner strut stents and absorbable polymers, Xience exhibits similar results in all important clinical endpoints.

Combined associations of body mass index and adherence to a Mediterranean-like diet with all-cause and cardiovascular mortality: A cohort study.

BACKGROUND: It is unclear whether the effect on mortality of a higher body mass index (BMI) can be compensated for by adherence to a healthy diet and whether the effect on mortality by a low adherence to a healthy diet can be compensated for by a normal weight. We aimed to evaluate the associations of BMI combined with adherence to a Mediterranean-like diet on all-cause and cardiovascular disease (CVD) mortality. METHODS AND FINDINGS: Our longitudinal cohort design included the Swedish Mammography Cohort (SMC) and the Cohort of Swedish Men (COSM) (1997-2017), with a total of 79,003 women (44%) and men (56%) and a mean baseline age of 61 years. BMI was categorized into normal weight (20-24.9 kg/m2), overweight (25-29.9 kg/m2), and obesity (30+ kg/m2). Adherence to a Mediterranean-like diet was assessed by means of the modified Mediterranean-like diet (mMED) score, ranging from 0 to 8; mMED was classified into 3 categories (0 to <4, 4 to <6, and 6-8 score points), forming a total of 9 BMI × mMED combinations. We identified mortality by use of national Swedish registers. Cox proportional hazard models with time-updated information on exposure and covariates were used to calculate the adjusted hazard ratios (HRs) of mortality with their 95% confidence intervals (CIs). Our HRs were adjusted for age, baseline educational level, marital status, leisure time physical exercise, walking/cycling, height, energy intake, smoking habits, baseline Charlson's weighted comorbidity index, and baseline diabetes mellitus. During up to 21 years of follow-up, 30,389 (38%) participants died, corresponding to 22 deaths per 1,000 person-years. We found the lowest HR of all-cause mortality among overweight individuals with high mMED (HR 0.94; 95% CI 0.90, 0.98) compared with those with normal weight and high mMED. Using the same reference, obese individuals with high mMED did not experience significantly higher all-cause mortality (HR 1.03; 95% CI 0.96-1.11). In contrast, compared with those with normal weight and high mMED, individuals with a low mMED had a high mortality despite a normal BMI (HR 1.60; 95% CI 1.48-1.74). We found similar estimates among women and men. For CVD mortality (12,064 deaths) the findings were broadly similar, though obese individuals with high mMED retained a modestly increased risk of CVD death (HR 1.29; 95% CI 1.16-1.44) compared with those with normal weight and high mMED. A main limitation of the present study is the observational design with self-reported lifestyle information with risk of residual or unmeasured confounding (e.g., genetic liability), and no causal inferences can be made based on this study alone. CONCLUSIONS: These findings suggest that diet quality modifies the association between BMI and all-cause mortality in women and men. A healthy diet may, however, not completely counter higher CVD mortality related to obesity.

Increased availability of paracetamol in Sweden and incidence of paracetamol poisoning: using laboratory data to increase validity of a population-based registry study.

PURPOSE: To estimate the incidence trend and outcome of paracetamol poisoning, in relation to increased availability of paracetamol from non-pharmacy outlets in 2009. METHOD: Patients' serum paracetamol results over 14 years (2000-2013) from 20 (out of 21) regions in Sweden were linked to national registers of hospital care, cause of death, and prescriptions. Paracetamol poisonings were defined by serum paracetamol levels, hospital diagnoses, or cause of death. The change in incidence of poisonings following increased availability of paracetamol was analysed by using segmental regression of time series. RESULTS: Of the 12 068 paracetamol poisonings, 85% were classified as intentional self-harm. Following increased availability from non-pharmacy outlets, there was a 40.5% increase in the incidence of paracetamol poisoning, from 11.5/100 000 in 2009 to 16.2/100 000 in 2013. Regression analyses indicated a change in the trend (p < 0.0001) but not an immediate jump in the incidence (p = 0.5991) following the increased availability. Adjusting for trends in hospital episodes for self-harm, suicides, and the sales volume of paracetamol did not influence the result. All-cause mortality at 30 days (3.2%) did not change over time. CONCLUSIONS: The incidence of paracetamol poisoning in Sweden has increased since 2009, contrasting the decreased incidence in the period of 2007-2009. The change in trend was temporally associated with the introduction of availability of paracetamol from non-pharmacy outlets but did not appear to be related to sales volume of paracetamol or general trends in self-harm or suicides. © 2017 Commonwealth of Australia. Pharmacoepidemiology and Drug Safety © 2017 John Wiley & Sons, Ltd.

Low real-world early stent thrombosis rates in ST-elevation myocardial infarction patients and the use of bivalirudin, heparin alone or glycoprotein IIb/IIIa inhibitor treatment: A nationwide Swedish registry report.

BACKGROUND: In recent studies of primary percutaneous coronary intervention (PCI), bivalirudin compared with heparin has been associated with increased risk of stent thrombosis (ST). Our aim was to describe incidence and outcome of definite, early ST in a large contemporary primary PCI population divided in antithrombotic therapy subgroups. METHODS AND RESULTS: A prospective, observational cohort study of all 31,258 ST-elevation myocardial infarction patients who received a stent in Sweden from January 2007 to July 2014 in the SWEDEHEART registry was conducted. Patients were divided into 3 groups: bivalirudin, heparin alone, or glycoprotein IIb/IIIa inhibitor treated. Primary outcome measure was incidence of definite early ST (within 30 days of PCI). Secondary outcomes included all-cause mortality. Incidence of early ST was low, regardless of bivalirudin, heparin alone, or glycoprotein IIb/IIIa inhibitor treatment (0.84%, 0.94%, and 0.83%, respectively). All-cause mortality at 1 year was 20.7% for all ST patients (n = 265), compared with 9.1% in those without ST (n = 31,286; P < .001). Patients with ST days 2-30 had numerically higher all-cause mortality at 1 year compared with patients with ST days 0-1 (23% vs 16%, P = .20). CONCLUSION: In this real-world observational study of 31,258 ST-elevation myocardial infarction patients, the incidence of early ST was low, regardless of antithrombotic treatment strategy. Early ST was associated with increased mortality. Numerically higher all-cause mortality at 1 year was noted with ST days 2-30 compared with ST days 0-1 post-PCI.

Body weight and risk of atrial fibrillation in 7,169 patients with newly diagnosed type 2 diabetes; an observational study.

BACKGROUND: Obesity, type 2 diabetes and atrial fibrillation (AF) are closely associated, but the underlying mechanisms are not fully understood. We aimed to explore associations between body mass index (BMI) or weight change with risk of AF in patients with type 2 diabetes. METHODS: A total of 7,169 participations with newly diagnosed type 2 diabetes were stratified according to baseline BMI, and after a second BMI measurement within 18 months, further grouped according to relative weight change as "weight gain" (>1 BMI unit), "stable weight" (+/- 1 BMI unit) and "weight loss" (<1 BMI unit). The mean follow-up period was 4.6 years, and the risk of AF was estimated using adjusted Cox regression models. RESULTS: Average age at diabetes diagnosis was 60 years and the patients were slightly obese (mean BMI 30.2 kg/m(2)). During follow-up, 287 patients developed incident AF, and those with overweight or obesity at baseline had 1.9-fold and 2.9-fold higher risk of AF, respectively, than those with normal BMI. The 14% of the patients with subsequent weight gain had 1.5-fold risk of AF compared with those with stable weight or weight loss. CONCLUSIONS: In patients with newly diagnosed type 2 diabetes, baseline overweight and obesity, as well as modest weight increase during the first 18 months after diagnosis, were associated with a substantially increased risk of incident AF. Patients with type 2 diabetes may benefit from efforts to prevent weight gain in order to reduce the risk of incident AF. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01121315.

Symptoms and ECG changes precede sudden cardiac death in hypertrophic cardiomyopathy-A nationwide study among the young in Sweden.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a major cause of sudden cardiac death (SCD) in the young. We aimed to characterize detailed family history, symptoms, hospital utilization and ECG changes before SCD. METHODS: We extracted all cases suffering SCD with HCM from the SUDDY cohort, which includes all cases of SCD between 2000-2010 in Sweden among individuals aged 0-35 years along with their controls. We gathered data from mandatory national registries, autopsy reports, medical records, ECGs (including military conscripts), and detailed family history from an interview-based questionnaire (with relatives, post-mortem). RESULTS: Thirty-eight cases (7 female), mean age 22 years, with HCM were identified. Among these, 71% presented with possible cardiac symptoms (chest pain [26%], syncope [22%], palpitations [37%]), before death; 69% received medical care (vs 21% in controls) within 180 days before death. The majority (68%) died during recreational activity (n = 14) or exercise/competitive sports (n = 12). Fifteen (39%) had a known cardiac disorder prior to death, with HCM being diagnosed pre-mortem in nine cases. 58% presented with abnormal ECG recordings pre-mortem, and 50% had a positive family history (1st-3rd generation) for heart disease. CONCLUSION: In this comprehensive, nationwide study of SCD due to HCM, 87% (33/38) of cases had one or more abnormality prior to death, including cardiac symptoms, a positive family history, known cardiac disease or ECG abnormalities. They sought medical care prior death, to a larger extent than controls. These findings suggest that cardiac screening should be expanded beyond competitive athletes to aid SCD prevention in the young population with HCM.

Family History and Warning Symptoms Precede Sudden Cardiac Death in Arrhythmogenic Right Ventricular Cardiomyopathy (from a Nationwide Study in Sweden).

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiac disease explaining about 4% of sudden cardiac death (SCD) cases in the young in Sweden. This study aimed to describe the circumstances preceding SCD in all victims <35 years of age who received an autopsy-confirmed diagnosis of ARVC from January 1, 2000, to December 31, 2010, in Sweden (n = 22). Data on demographics, medical and family history, circumstances of death, and anatomopathological findings were collected from several compulsory national health registries, clinical records, family interviews, and autopsy reports. Registry-based data were compared with age-matched, gender-matched, and geographically-matched population controls. During the 6 months preceding SCD, 15 cases (68%) had experienced symptoms of cardiac origin, mainly syncope or presyncope (54%) and chest discomfort (27%). A total of 8 cases (36%) had sought medical care because of cardiac symptoms. The occurrence of hospital visits was significantly increased in cases compared with controls (odds ratio 4.62 [1.35 to 15.8]). A total of 10 cases (45%) had a family history of SCD. The most common activity at the time of death was exercise (41%). A complete cardiac investigation was seldom performed; only 1 case was diagnosed with ARVC before death. In conclusion, in this nationwide study, we observed a high prevalence of symptoms of cardiac origin, healthcare use, and family history of SCD preceding SCD in the young caused by ARVC. Increased awareness of these warning signals in younger patients is critical to improving risk stratification and early disease detection.

Cohort profile: the Swedish study of SUDden cardiac Death in the Young (SUDDY) 2000-2010: a complete nationwide cohort of SCDs.

PURPOSE: The rationale behind the SUDden cardiac Death in the Young (SUDDY) cohort was to provide a complete nationwide, high-quality platform with integrated multisource data, for clinical and genetic research on sudden cardiac death (SCD) in the young, with the ultimate goal to predict and prevent SCD. PARTICIPANTS: The cohort contains all SCD victims <36 years, in Sweden during the period 2000-2010. We assigned five population-based controls per case, together with parents of cases and controls, in total 15 633 individuals. Data of all individuals were extracted from multiple mandatory registries; the National Patient Registry, the Medical Birth Registry, the Prescribed Drug registry, the Cause of Death registry, the Multigeneration Registry, combined with socioeconomic data from Statistics Sweden. From SCD victims, the autopsy report, medical records, ECGs, parental information and biological samples were gathered. FINDINGS TO DATE: We identified 903 individuals diagnosed with SCD (67% men, 33% women). The cases comprised 236 infants <1 year of age (26%), 90 individuals aged 1-15 years (10%), 186 individuals aged 15-25 years (21%) and 391 aged 25-35 years (43%). Hospitalisations and outpatient clinic visits due to syncope were significantly more common among cases than controls. DNA obtained from dried blood spots tests (DBS) stored from birth was equally suitable as venous blood samples for high-throughput genetic analysis of SCD cases. FUTURE PLANS: We will explore the SUDDY cohort for symptoms and healthcare consumption, socioeconomic variables and family history of SCD. Furthermore, we will perform whole exome sequencing analysis on DNA of cases obtained from DBS or postmortem samples together with parental blood samples in search for gene variants associated with cardiac disease. The genetic analysis together with data compiled in the nationwide cohort is expected to improve current knowledge on the incidence, aetiology, clinical characteristics and family history of SCD.

Development of gut microbiota during the first 2 years of life.

Although development of microbiota in childhood has been linked to chronic immune-related conditions, early childhood determinants of microbiota development have not been fully elucidated. We used 16S rRNA sequencing to analyse faecal and saliva samples from 83 children at four time-points during their first 2 years of life and from their mothers. Our findings confirm that gut microbiota in infants have low diversity and highlight that some properties are shared with the oral microbiota, although inter-individual differences are present. A considerable convergence in gut microbiota composition was noted across the first 2 years of life, towards a more diverse adult-like microbiota. Mode of delivery accounted for some of the inter-individual variation in early childhood, but with a pronounced attenuation over time. Our study extends previous research with further characterization of the major shift in gut microbiota composition during the first 2 years of life.

Radical reduction of cephalosporin use at a tertiary hospital after educational antibiotic intervention during an outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae.

OBJECTIVES: During an outbreak of extended-spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae at our hospital, we performed an educational antibiotic intervention aimed at reducing prescriptions of second- and third-generation cephalosporins and preventing increased use of fluoroquinolones and carbapenems. In this report, we describe the implementation strategy used and evaluate the intervention effect according to Cochrane recommendations. METHODS: New recommendations for empirical intravenous antibiotic treatment were communicated to prescribers throughout the hospital by infectious diseases physicians working with Strama (the Swedish strategic programme against antibiotic resistance). No restrictive measures were used. The intervention effect was analysed with interrupted time series (ITS) regression analysis of local and national monthly antibiotic sales data. RESULTS: A radical immediate and sustained reduction was demonstrated for the cephalosporins targeted in the intervention, whereas consumption of piperacillin/tazobactam and penicillin G increased substantially. Fluoroquinolone and carbapenem use was essentially unchanged. The ESBL outbreak subsided and no increased resistance to piperacillin/tazobactam was detected in K. pneumoniae, Escherichia coli or Pseudomonas aeruginosa blood isolates during the 2.5 year follow-up. CONCLUSIONS: Our study clearly demonstrates that an educational intervention can have an immediate and profound effect on antibiotic prescription patterns at a large tertiary hospital. ITS regression analysis of local and national antibiotic sales data was valuable to readily assess the immediate and sustained effects of the intervention.

Association between adoption of evidence-based treatment and survival for patients with ST-elevation myocardial infarction.

CONTEXT: Only limited information is available on the speed of implementation of new evidence-based and guideline-recommended treatments and its association with survival in real life health care of patients with ST-elevation myocardial infarction (STEMI). OBJECTIVE: To describe the adoption of new treatments and the related chances of short- and long-term survival in consecutive patients with STEMI in a single country over a 12-year period. DESIGN, SETTING, AND PARTICIPANTS: The Register of Information and Knowledge about Swedish Heart Intensive Care Admission (RIKS-HIA) records baseline characteristics, treatments, and outcome of consecutive patients with acute coronary syndrome admitted to almost all hospitals in Sweden. This study includes 61,238 patients with a first-time diagnosis of STEMI between 1996 and 2007. MAIN OUTCOME MEASURES: Estimated and crude proportions of patients treated with different medications and invasive procedures and mortality over time. RESULTS: Of evidence-based treatments, reperfusion increased from 66% (95%, confidence interval [CI], 52%-79%) to 79% (95% CI, 69%-89%; P < .001), primary percutaneous coronary intervention from 12% (95% CI, 11%-14%) to 61% (95% CI, 45%-77%; P < .001), and revascularization from 10% (96% CI, 6%-14%) to 84% (95% CI, 73%-95%; P < .001). The use of aspirin, clopidogrel, ß-blockers, statins, and angiotensin-converting enzyme (ACE) inhibitors all increased: clopidogrel from 0% to 82% (95% CI, 69%-95%; P < .001), statins from 23% (95% CI, 12%-33%) to 83% (95% CI, 75%-91%; P < .001), and ACE inhibitor or angiotensin II receptor blockers from 39% (95% CI, 26%-52%) to 69% (95% CI, 58%-70%; P < .001). The estimated in-hospital, 30-day and 1-year mortality decreased from 12.5% (95% CI, 4.3%-20.6%) to 7.2% (95% CI, 1.7%-12.6%; P < .001); from 15.0% (95% CI, 6.2%-23.7%) to 8.6% (95% CI, 2.7%-14.5%; P < .001); and from 21.0% (95% CI, 11.0%-30.9%) to 13.3% (95% CI, 6.0%-20.4%; P < .001), respectively. After adjustment, there was still a consistent trend with lower standardized mortality over the years. The 12-year survival analyses showed that the decrease of mortality was sustained over time. CONCLUSION: In a Swedish registry of patients with STEMI, between 1996 and 2007, there was an increase in the prevalence of evidence-based treatments. During this same time, there was a decrease in 30-day and 1-year mortality that was sustained during long-term follow-up.

Serum 25-hydroxyvitamin D is associated with fracture risk only during periods of seasonally high levels in women with a high body mass index.

Serum 25-hydroxyvitamin D (S-25OHD) is used to assess vitamin D status and is known to be affected by season and fat mass. Because these factors are often ignored when interpreting S-25OHD, assessment of vitamin D associations with disease outcomes may be distorted. We aimed to investigate the impact of season of blood draw and fat mass on the association of S25OHD with fracture risk. We enrolled 5000 women, mean ± SD age 68 ± 7 years, with dual-energy x-ray absorptiometry (DXA) scans and blood collection in a population-based cohort. Proportional hazards regression, stratified by season and fat mass, was used to determine hazard ratios (HRs) of fracture according to categories of S-25OHD. Our secondary exposures were serum 1,25-dihydroxycholecalciferol (1,25-(OH)2 D3 ), the most active vitamin D metabolite and plasma parathyroid hormone (P-PTH). During an average of 9.2 years of follow-up, 1080 women had a fracture. Women with S-25OHD <30 nmol/L drawn during sunny months (May-October) had a multivariable-adjusted fracture HR of 2.06 (95% CI, 1.27-3.35) compared with those with S-25OHD >60 nmol/L; those with S-25OHD 30-40 nmol/L had an HR of 1.59 (95% CI, 1.12-2.26). In contrast, S-25OHD drawn during November through April was unrelated to fracture risk. The increased risk with low sunny season S-25OHD was seen only among women with body mass index (BMI) ≥25 kg/m2 or fat mass index (FMI) ≥9.8 kg/m2 . High fat mass and low S-25OHD were independently related to lower S-1,25-dihydroxycholecalciferol, which itself predicted fracture risk with samples collected during the sunny season. Irrespective of season, P-PTH was unrelated to fracture risk. We conclude that S-25OHD is associated with fracture risk only if drawn during periods of seasonally high levels in women with a high BMI. These results have implications for the evaluation of vitamin D status and can explain the lack of effect seen with vitamin D supplementation in many fracture trials. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Early Childhood Antibiotic Treatment for Otitis Media and Other Respiratory Tract Infections Is Associated With Risk of Type 1 Diabetes: A Nationwide Register-Based Study With Sibling Analysis.

OBJECTIVE: The effect of early-life antibiotic treatment on the risk of type 1 diabetes is debated. This study assessed this question, applying a register-based design in children up to age 10 years including a large sibling-control analysis. RESEARCH DESIGN AND METHODS: All singleton children (n = 797,318) born in Sweden between 1 July 2005 and 30 September 2013 were included and monitored to 31 December 2014. Cox proportional hazards models, adjusted for parental and perinatal characteristics, were applied, and stratified models were used to account for unmeasured confounders shared by siblings. RESULTS: Type 1 diabetes developed in 1,297 children during the follow-up (median 4.0 years [range 0-8.3]). Prescribed antibiotics in the 1st year of life (23.8%) were associated with an increased risk of type 1 diabetes (adjusted hazard ratio [HR] 1.19 [95% CI 1.05-1.36]), with larger effect estimates among children delivered by cesarean section (P for interaction = 0.016). The association was driven by exposure to antibiotics primarily used for acute otitis media and respiratory tract infections. Further, we found an association of antibiotic prescriptions in pregnancy (22.5%) with type 1 diabetes (adjusted HR 1.15 [95% CI 1.00-1.32]). In general, sibling analysis supported these results, albeit often with statistically nonsignificant associations. CONCLUSIONS: Dispensed prescription of antibiotics, mainly for acute otitis media and respiratory tract infections, in the 1st year of life is associated with an increased risk of type 1 diabetes before age 10 years, most prominently in children delivered by cesarean section.

Implementation of sacubitril/valsartan in Sweden: clinical characteristics, titration patterns, and determinants.

AIMS: The aim of this study is to study the introduction of sacubitril/valsartan (sac/val) in Sweden with regards to regional differences, clinical characteristics, titration patterns, and determinants of use and discontinuation. METHODS AND RESULTS: A national cohort of heart failure was defined from the Swedish Prescribed Drug Register and National Patient Register. A subcohort with additional data from the Swedish Heart Failure Registry (SwedeHF) was also studied. Cohorts were subdivided as per sac/val prescription and registration in SwedeHF. Median sac/val prescription rate was 20 per 100 000 inhabitants. Between April 2016 and December 2017, we identified 2037 patients with ≥1 sac/val prescription, of which 1144 (56%) were registered in SwedeHF. Overall, patients prescribed with sac/val were younger, more frequently male, and had less prior cardiovascular disease than non-sac/val patients. In SwedeHF subcohort, patients prescribed with sac/val had lower ejection fraction. Overall, younger age [hazard ratio 2.81 (95% confidence interval 2.45-3.22)], registration in SwedeHF [1.97 (1.83-2.12)], male gender [1.50 (1.37-1.64)], ischaemic heart disease [1.50 (1.39-1.62)], lower left ventricular ejection fraction [3.06 (2.18-4.31)], and New York Heart Association IV [1.50 (1.22-1.84)] were predictors for sac/val use. As initiation dose in the sac/val cohort, 38% received 24/26 mg, 54% 49/51 mg, and 9% 97/103 mg. Up-titration to the target dose was achieved in 57% of the overall cohort over a median follow-up of 6 months. The estimated treatment persistence for any dose at 360 days was 82%. CONCLUSIONS: Implementation of sac/val in Sweden was slow and varied five-fold across different regions; younger age, male, SwedeHF registration, and ischaemic heart disease were among the independent predictors of receiving sac/val. Overall, treatment persistence and tolerability was high.

Impact of ischaemic heart disease severity and age on risk of cardiovascular outcome in diabetes patients in Sweden: a nationwide observational study.

OBJECTIVES: To compare short-term cardiovascular (CV) outcome in type 2 diabetes (T2D) patients without ischaemic heart disease (IHD), with IHD but no prior myocardial infarction (MI), and those with prior MI; and assess the impact on risk of age when initiating first-time glucose-lowering drug (GLD). DESIGN: Cohort study linking morbidity, mortality and medication data from Swedish national registries. PARTICIPANTS: First-time users of GLD during 2007-2016. OUTCOMES: Predicted cumulative incidence for the CV outcome (MI, stroke and CV mortality) was estimated. A Cox model was developed where age at GLD start and CV risk was modelled. RESULTS: 260 070 first-time GLD users were included, 221 226 (85%) had no IHD, 16 294 (6%) had stable IHD-prior MI and 22 550 (9%) had IHD+MI. T2D patients without IHD had a lower risk of CV outcome compared with the IHD populations (±prior MI), (3-year incidence 4.78% vs 5.85% and 8.04%). The difference in CV outcome was primarily driven by a relative greater MI risk among the IHD patients. For T2D patients without IHD, an almost linear association between age at start of GLD and relative risk was observed, whereas in IHD patients, the younger (<60 years) patients had a relative greater risk compared with older patients. CONCLUSIONS: T2D patients without IHD had a lower risk of the CV outcome compared with the T2D populations with IHD, primarily driven by a greater risk of MI. For T2D patients without IHD, an almost linear association between age at start of GLD and relative risk was observed, whereas in IHD patients, the younger patients had a relative greater risk compared with older patients. Our findings suggest that intense risk prevention should be the key strategy in the management of T2D patients, especially for younger patients.

Combined association of key risk factors on ischaemic outcomes and bleeding in patients with myocardial infarction.

OBJECTIVE: In patients with myocardial infarction (MI), risk factors for bleeding and ischaemic events tend to overlap, but the combined effects of these factors have scarcely been studied in contemporary real-world settings. We aimed to assess the combined associations of established risk factors using nationwide registries. METHODS: Using the Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies registry, patients with invasively managed MI in 2006-2014 were included. Six factors were assessed in relation to cardiovascular death (CVD)/MI/stroke, and major bleeding: age ≥65, chronic kidney disease, diabetes, multivessel disease, prior bleeding and prior MI. RESULTS: We studied 100 879 patients, of whom 20 831 (20.6%) experienced CVD/MI/stroke and 5939 (5.9%) major bleeding, during 3.6 years median follow-up. In adjusted Cox models, all factors were associated with CVD/MI/stroke, and all but prior MI were associated with major bleeding. The majority (53.5%) had ≥2 risk factors. With each added risk factor, there was a marked but gradual increase in incidence of the CVD/MI/stroke. This was seen also for major bleeding, but to a lesser extent, largely driven by prior bleeding as the strongest risk factor. CONCLUSIONS: The majority of patients with MI had two or more established risk factors. Increasing number of risk factors was associated with higher rate of ischaemic events. When excluding patients with prior major bleeding, bleeding incidence rate increased only minimally with increasing number of risk factors. The high ischaemic risk in those with multiple risk factors highlights an unmet need for additional preventive measures.

Rationale for a Swedish cohort consortium.

We herein outline the rationale for a Swedish cohort consortium, aiming to facilitate greater use of Swedish cohorts for world-class research. Coordination of all Swedish prospective population-based cohorts in a common infrastructure would enable more precise research findings and facilitate research on rare exposures and outcomes, leading to better utilization of study participants' data, better return of funders' investments, and higher benefit to patients and populations. We motivate the proposed infrastructure partly by lessons learned from a pilot study encompassing data from 21 cohorts. We envisage a standing Swedish cohort consortium that would drive development of epidemiological research methods and strengthen the Swedish as well as international epidemiological competence, community, and competitiveness.

Risk factors for subarachnoid haemorrhage: a nationwide cohort of 950 000 adults.

BACKGROUND: Subarachnoid haemorrhage (SAH) is a devastating disease, with high mortality rate and substantial disability among survivors. Its causes are poorly understood. We aimed to investigate risk factors for SAH using a novel nationwide cohort consortium. METHODS: We obtained individual participant data of 949 683 persons (330 334 women) between 25 and 90 years old, with no history of SAH at baseline, from 21 population-based cohorts. Outcomes were obtained from the Swedish Patient and Causes of Death Registries. RESULTS: During 13 704 959 person-years of follow-up, 2659 cases of first-ever fatal or non-fatal SAH occurred, with an age-standardized incidence rate of 9.0 [95% confidence interval (CI) (7.4-10.6)/100 000 person-years] in men and 13.8 [(11.4-16.2)/100 000 person-years] in women. The incidence rate increased exponentially with higher age. In multivariable-adjusted Poisson models, marked sex interactions for current smoking and body mass index (BMI) were observed. Current smoking conferred a rate ratio (RR) of 2.24 (95% CI 1.95-2.57) in women and 1.62 (1.47-1.79) in men. One standard deviation higher BMI was associated with an RR of 0.86 (0.81-0.92) in women and 1.02 (0.96-1.08) in men. Higher blood pressure and lower education level were also associated with higher risk of SAH. CONCLUSIONS: The risk of SAH is 45% higher in women than in men, with substantial sex differences in risk factor strengths. In particular, a markedly stronger adverse effect of smoking in women may motivate targeted public health initiatives.