Swedish Hospital Discharge Register Research Articles

Heredity of pregnancy-related pelvic girdle pain in Sweden.

Pelvic girdle pain during and after pregnancy is a major public health problem with significant daily problems for affected women and their families. There is now accumulating evidence that pregnancy-related pelvic girdle pain originates from the sacroiliac joints and the pubic symphysis as well as their extra-articular ligaments. However, the heritability of the disease remains to be determined. We hypothesized that there is an increased familial risk of pregnancy-related pelvic girdle pain. A population-based national database linkage registry study of approximately 9.3 million individuals within 4.2 million families in Sweden with a recruitment period from 1997 to 2018. The Swedish Multi-generation register was used to find female pairs of twins, full siblings, half-siblings and first cousins where both in the pairs had a completed pregnancy. The outcome measure was diagnosis of pregnancy-related pelvic girdle pain (International Classification of Diseases-10 O26.7 [1997-2018]) in the first pregnancy. Data was obtained from the Swedish Hospital Discharge Register, the Swedish Outpatient Care Register, the Swedish Medical Birth Register, the Primary Healthcare Register, and Medical Treatment Register. Cox regression analysis was used to calculate adjusted estimated effect of the exposure variable familial history of pregnancy-related pelvic girdle pain on the outcome variable pregnancy-related pelvic girdle pain at first birth. From the registers, 1 010 064 women pregnant with their first child within 795 654 families were collected. In total, 109 147 women were diagnosed with pregnancy-related pelvic girdle pain. The adjusted hazard ratio for a familial risk of pregnancy-related pelvic girdle pain was 2.09 (95% CI 1.85-2.37) among twins (monozygotic and dizygotic), 1.78 (95% CI 1.74-1.82) in full siblings, 1.16 (95% CI 1.06-1.28) in half-siblings from the mother, 1.09 (95% CI 1.024-1.16) in half-siblings from the father and 1.09 (95% CI 1.07-1.12) in first cousins. This nationwide observational study showed a familial clustering of pregnancy-related pelvic girdle pain. The hazard ratio for the condition was associated with the degree of relatedness, suggesting that heredity factors contribute to the development of pregnancy-related pelvic girdle pain. There is no causal treatment available for pregnancy-related pelvic girdle pain and further studies are now encouraged to clarify the specific genetic factors that contribute to the disease and for future targeted interventions.

Decreasing incidence of knee arthroscopy in Sweden between 2002 and 2016: a nationwide register-based study.

Several randomized trials have demonstrated the lack of effect of arthroscopic lavage as treatment for knee osteoarthritis (OA). These results have in turn resulted in a change in Swedish guidelines and reimbursement. We aimed to investigate the use of knee arthroscopies in Sweden between 2002 and 2016. Patient demographics, regional differences, and the magnitude of patients with knee OA undergoing knee arthroscopy were also analyzed. Trends in knee arthroscopy were investigated using the Swedish Hospital Discharge Register (SHDR) to conduct a nationwide register-based study including all adults (>18 years of age) undergoing any knee arthroscopy between 2002 and 2016. The total number of knee arthroscopies performed during the studied period was 241,055. The annual surgery rate declined in all age groups, for males and females as well as patients with knee OA. The incidence dropped from 247 to 155 per 105inhabitants. Over 50% of arthroscopies were performed in metropolitan regions. We showed a dramatic decline in knee arthroscopy. There is variability in the surgery rate between males and females and among the regions of Sweden.

Mortality following proximal humerus fracture—a nationwide register study of 147,692 fracture patients in Sweden

SummaryLittle is known about survival after proximal humerus fracture. In this manuscript, we found the mortality to be high (almost four times higher than in age- and sex-matched controls). While frailty hip fracture has gained attention, we hope our manuscript will shed light on frailty proximal humerus fracture patients.IntroductionProximal humerus fractures (PHF) are common and occur mostly after the 6th decade of life. While mortality following PHF has been reported previously, mortality data after longer follow-up on a national level is lacking.MethodsWe obtained data from the Swedish Hospital Discharge Register (SHDR), on all adult patients (≥ 18 years) with a diagnosis of PHF (S42.2, S42.20, or S42.21) for the period between 2001 and 2016. We used the Swedish Cause of Death Register (SCDR) to investigate mortality in the fracture cohort. We compared the mortality of fracture patients with age- and sex-matched population-based mortality data obtained from Statistics Sweden.ResultsA total of 147 692 PHF patients were identified, with a male to female ratio of 1:3. The mean age was 69 years (range, 18 to 111). Most patients were treated non-surgically (n = 126,487, 86%). The crude mortality rate was 2.2% at 1 month, 4.1% at 3 months, 8.5% at 12 months, and 24% at 48 months after sustaining a PHF. Mortality increased with age; however, the standardized mortality rate (SMR) was highest among young patients. SMR was 5.4 in the 18- to 39-year age group, 3.9 in the 40- to 64-year age group, 1.8 in the 65–79-year age group, and 1.2 in the ≥ 80-year-old population. The age-adjusted SMR was 3.9 in the whole adult PHF population.ConclusionThe mortality rate and SMR suggest that PHF patients are heterogeneous. Some older PHF patients may benefit from specialized care (e.g., orthogeriatric), and this should be evaluated in future studies.

Morphology-Voltage-P-wave duration (MVP) score in prediction of incident atrial fibrillation in an elderly epidemiologic cohort

Abstract Background Interatrial block (IAB) on electrocardiography (ECG) and reduced P wave voltage reflect atrial abnormalities which may contribute to development of atrial fibrillation (AF). Purpose We aimed to assess the value of a recently proposed ECG risk score that combines the morphology, voltage and length of the P wave (MVP score) for prediction of incident AF in a prospective population-based setting. Material and methods The study population is based on the large, prospective Malmö Preventative Project (MPP) cohort. We included subjects without a history of AF, with a readable ECG in sinus rhythm and an echocardiography performed in 2002–2006 (n=983, mean age 70±5 years, 38% females). Median follow-up was 4.2 (IQR 3.7–4.8) years. ECGs were digitally processed using the Glasgow algorithm. Advanced IAB (aIAB) was defined as a P-wave ≥120 ms and biphasic morphology (+/−) in inferior leads, partial IAB (pIAB) as P-wave ≥120 ms and a monophasic positive morphoology in inferior leads. MVP score was calculated based on the P-wave morphology in inferior leads, voltage in lead 1, and P-wave duration (Table 1).Incident AF events (n=66, 7%) were obtained from the Swedish Hospital Discharge Register and Cause of Death Register. Cox regression analysis and Kaplan Meier curve analysis were used to study the association of echocardiographic and P-wave characteristics with the risk of new onset AF. Results At baseline the mean MVP score was 1±1, none of the subjects had MVP score above 4. MVP score correlated with left atrial (LA) area: Pearson r=0.192, p<0.001. After adjustment for age, gender and LA enlargement expressed as LA area >20 cm2, new onset AF was associated with MVP score 4 (HR 6.17, 95% CI 1.76–21.64 compared to those with MVP score <4, Figure 1). Neither aIAB (univariate HR 1.93 CI 95% 0.82–4.56), nor pIAB (univariate HR 1.16 CI 95% 0.52–2.55) predicted incident AF. Conclusion In a population-based elderly epidemiological cohort, the ECG-based MVP score was significantly associated with incident AF, independently of LA enlargement. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The Swedish Heart-Lung Foundation

Epidemiology of Amyloidosis and Genetic Pathways to Diagnosis and Typing

We reviewed our studies on epidemiology and germline genetics of amyloidosis. In epidemiology, we considered both hereditary and non-hereditary amyloidosis. As the source of data, we used the nationwide Swedish hospital discharge register. We estimated the incidence of hereditary ATTR amyloidosis, for which Sweden is a global endemic area, at 2/million. Surprisingly, the disease was also endemic within Sweden; the incidence in the province with the highest incidence was 100 times higher than in the rest of Sweden. Risk of non-Hodgkin lymphoma increased five-fold in the affected individuals. Among non-hereditary amyloidosis, the incidence for AL amyloidosis (abbreviated as AL) was estimated at 3.2/million, with a median survival time of 3 years. Secondary systemic amyloidosis (most likely AA amyloidosis) showed an incidence of 1.15/million for combined sexes. The female rate was two times higher than the male rate, probably relating to the higher female prevalence of rheumatoid arthritis. The median survival time was 4 years. We also identified patients who likely had familial autoinflammatory disease, characterized by early onset and immigrant background from the Eastern Mediterranean area. Young Syrian descendants had the highest incidence rate, which was over 500 times higher than that in individuals with Swedish parents. Germline genetics focused on AL on which we carried out a genome-wide association study (GWAS) in three AL cohorts (N = 1129) from Germany, UK, and Italy. Single nucleotide polymorphisms (SNPs) at 10 loci showed evidence of an association at p < 10−5; some of these were previously documented to influence multiple myeloma (MM) risk, including the SNP at the IRF4 binding site. In AL, SNP rs9344 at the splice site of cyclin D1, influencing translocation (11;14), reached the highest significance, p = 7.80 × 10−11; the SNP was only marginally significant in MM. The locus close to gene SMARCD3, involved in chromatin remodeling, was also significant. These data provide evidence for common genetic susceptibility to AL and MM. We continued by analyzing genetic associations in nine clinical profiles, characterized by organ involvement or Ig profiles. The light chain only (LCO) profile associated with the SNP at the splice site of cyclin D1 with p = 1.99 × 10−12. Even for the other profiles, distinct genetic associations were found. It was concluded that the strong association of rs9344 with LCO and t(11;14) amyloidosis offer attractive mechanistic clues to AL causation. Mendelian randomization analysis identified associations of AL with increased blood monocyte counts and the tumor necrosis factor receptor superfamily member 17 (TNFRSF17 alias BCMA) protein. Two other associations with the TNFRSF members were found. We discuss the corollaries of the findings with the recent success of treating t(11;14) AL with a novel drug venetoclax, and the application of BCMA as the common target of plasma cell immunotherapies.

Increased incidence of heart failure in patients with severe obstructive sleep apnoea: a long-term prospective cohort study

Abstract Background Obstructive sleep apnoea (OSA) is highly prevalent among patients with heart failure. Accumulating research data suggest that this association is bidirectional. Less is known regarding the long-term impact of OSA and continuous positive airway pressure (CPAP) treatment on incident heart failure. Purpose We addressed the association of severe OSA with development of heart failure, and consequently addressed the impact of efficient CPAP treatment in a sleep clinic cohort. Methods The “Sleep Apnea Patients in Skaraborg (SAPIS)” project was a single center (two sites), open-label, prospective cohort study, conducted in Sweden between 2005 and 2018. All consecutive adults admitted to the Skaraborg Hospital between 2005 and 2011 were registered in a local database, and the follow-up ended in May 2018. Anthropomorphic and clinical characteristics as well as results of the diagnostic cardiorespiratory recordings were documented. Treatment of OSA was based on the clinical routines. OSA was defined as an apnoea-hypopnoea index (AHI) of at least 5 events/hr, and severe OSA consisted of patients with an AHI ≥30 events/hr. Median follow-up for the entire cohort was 8.8 years (interquartile range 7.5–10.1 years). Data regarding incident heart failure were obtained from the medical records and the Swedish Hospital Discharge Register. CPAP use (downloaded reports from the devices) of at least 4 hrs/night was defined as efficient treatment. Results Among 4239 patients with diagnostic sleep recordings, 3185 were free of a known cardiac disease at baseline. Severe OSA was observed among 953 (29.9%). Severe OSA significantly predicted incident heart failure (hazard ratio [HR] 2.42; 95% confidence interval [CI] 1.44–4.06) compared to adults with AHI <30 events/hr, adjusted for age, gender, obesity, hypertension and diabetes mellitus. The adjusted HR for severe OSA was 2.82 (95% CI 1.33–5.99) among inefficiently treated/untreated patients whereas the risk was lower but still meaningful among the individuals who were adherent to CPAP (HR 2.25; 95% CI 0.99–5.15) Conclusion Our results suggest that severe OSA is associated with increased risk for development of heart failure. More than 4 hours of CPAP use per night may be necessary for OSA patients in the primary prevention models. CHF-free survival Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): ALF

Distal Biceps Tendon Rupture Surgery: Changing Incidence in Finnish and Swedish Men Between 1997 and 2016

Distal biceps tendon rupture is a relatively rare injury usually occurring with excess external extension force applied to a flexed elbow. The aim of this study was to examine the incidence of distal biceps tendon rupture surgery in the Finnish and Swedish adult population between the years 1997 and 2016. A secondary aim was to investigate the distal biceps rupture incidence in the Swedish population in 2001 to2016. We assessed the number and rate of distal biceps tendon rupture surgery using the Finnish and Swedish Hospital Discharge Register as databases. The study included the entire Finnish and Swedish adult population aged 18 years and older between January 1, 1997 and of December 31,2016. During the study period, 2,029 patients had a distal biceps tendon rupture in Finland, and the corresponding figure was 2,000 in Sweden. The rate of distal biceps tendon rupture surgery increased steeply, but equally, in both countries, in Finnish men from 1.3 per 100,000 person-years in 1997 to 9.6 in 2016, and in Swedish men from 0.2 in 1997 to 5.6 in 2016. The incidence of distal biceps tendon rupture in Sweden increased in men from 1.6 to 10.0 per 100,000 person-years from 2001 to2016. There was a 7-fold and a 28-fold increase in the incidence of distal biceps tendon rupture surgery in Finnish and Swedish men during 1997 to 2016. The incidence of distal biceps tendon rupture rose 6-fold in Swedish men in 2001 to2016. Prognostic IV.

Risk factors for intracerebral haemorrhage - Results from a prospective population-based study.

IntroductionWhile the relationship between hypertension and incident intracerebral haemorrhage is well established, other risk factors are less clear. This study examined risk factors for primary intracerebral haemorrhage, separately for lobar and non-lobar intracerebral haemorrhage.Patients and methodsIncidence of intracerebral haemorrhage was studied among 28,416 individuals from the population-based Malmö Diet and Cancer cohort. Intracerebral haemorrhage cases were ascertained using the Swedish Hospital Discharge Register and the Stroke Register of Malmö, validated by review of hospital records and images, and classified by location by a neuroradiologist. Multivariable Cox regression was used.ResultsThree hundred and thirty-three intracerebral haemorrhages occurred, mean follow-up time was 18.4 years. Systolic blood pressure (hazard ratio per 10 mmHg 1.19 [95% confidence interval 1.13–1.26], diastolic blood pressure (hazard ratio 1.42 [1.27–1.59]), oral anticoagulants (hazard ratio 4.26 [2.17–8.38]), smoking (hazard ratio 1.45 [1.14–1.87]), living alone (hazard ratio 1.32 [1.04–1.69]) and low apolipoprotein B (hazard ratio per 10 mg/dL: 0.94 [0.90–0.99]) were significantly associated with incident intracerebral haemorrhage after multivariable adjustment. Systolic blood pressure, smoking and oral anticoagulants were associated with lobar intracerebral haemorrhage. Systolic blood pressure, diastolic blood pressure, living alone and diabetes were associated with non-lobar intracerebral haemorrhage. Diabetes and diastolic blood pressure showed significantly different relationships with lobar and non-lobar intracerebral haemorrhage. Alcohol, apolipoprotein A1, body mass index, waist circumference, physical activity and education were not independently associated with intracerebral haemorrhage.Discussion and conclusions: Blood pressure, smoking, low apolipoprotein B, oral anticoagulants and living alone were associated with intracerebral haemorrhage. Diabetes was associated with non-lobar intracerebral haemorrhage only. Further research is required on differences between lobar and non-lobar intracerebral haemorrhage.

The Association Between Cancer and Dementia: A National Cohort Study in Sweden.

Background: Previous studies have found that the incidence of dementia is lower in patients with cancer. However, the impact of survival bias, as well as the confounding by medical treatment, have not been fully addressed. We aimed to explore the subsequent risk of dementia in different follow-up intervals among patients with cancer, as well as the risk before the diagnosis of cancer.Methods: By using the Swedish Cancer Register and the Swedish Hospital Discharge Register, we systematically examined the risk of dementia among patients diagnosed with 35 different types of cancer. Standardized incidence ratios (SIRs) were used to calculate the relative risk.Results: The subsequent risk of dementia in patients with cancer decreased by 21% compared to matched cancer-free controls (SIR = 0.79, 95% CI 0.78–0.80). For specific cancer sites, 21 of them had a significantly lower risk of subsequent dementia. The decreased risk of dementia was also significant before the diagnosis of cancer. However, the risk was higher among patients with cancer who survived for more than 10 years' post-diagnosis (SIR = 1.37, 95% CI 1.32–1.41).Conclusions: In this population-based study, we found that the risk of dementia was lower among patients with cancer, and the risk was also lower before the diagnosis of cancer. This suggests that lower dementia risk is not simply due to bias. However, the underlying mechanisms need to be explored further.

Familial risks between Graves disease and Hashimoto thyroiditis and other autoimmune diseases in the population of Sweden

Genetic and family studies have indicated that Graves disease and Hashimoto thyroiditis have a heritable component which appears to be shared to some extend also with some other autoimmune diseases (AIDs). In the present nation-wide study we describe familial risk for Graves disease and Hashimoto thyroiditis identified from the Swedish Hospital Discharge Register (years 1964 through 2012) and the Outpatient Register (2001 through 2012). Family relationships were obtained from the Multigeneration Register and cancers from the Cancer Registry. Familial standardized incidence ratios (SIRs) were calculated for 29,005 offspring with Graves disease and for 25,607 offspring with Hashimoto thyroiditis depending on any of 43 AIDs in parents or siblings. The concordant familial risks for Graves disease and Hashimoto thyroiditis were 3.85 and 4.75, higher for men than for women. The familial risks were very high (11.35, Graves and 22.06, Hashimoto) when both a parent and a sibling were affected. Spousal familial risks were higher for Hashimoto thyroiditis (1.98/1.93) than for Graves disease (1.48/1.50). For Graves disease, 24 discordant AIDs showed a significant association; for Hashimoto thyroiditis, 20 discordant associations were significant. All significant discordant associations were positive for the two thyroid AIDs, with the exception of Hashimoto thyroiditis with Reiter disease. Overall 8 associations were significant only for Graves disease and 6 Hashimoto thyroiditis. The overall high concordant familial risks for Graves disease and Hashimoto thyroiditis suggest a strong genetic contribution to the familial risk. Significant familial associations among more than half of the 43 AIDs attest to the extensive polyautoimmunity among thyroid AIDs.

1444Metabolically healthy obesity (MHO) in the Malmo Diet Cancer Study - epidemiology and prospective risks

Abstract Background/Aims Metabolically healthy obesity (MHO) is a controversial topic, since the underlying mechanisms and contributing factors behind this phenotype remain unclear. Here we aimed to investigate the characteristics of MHO, as well as prospective mortality risk. Method A cross-sectional analysis was carried out in a subsample of 3,812 obese subjects (BMI ≥30 kg/m2) selected from the Malmo Diet Cancer Study (MDCS) cohort (n=28,403). Subjects with MHO (n=1182; mean age 58±7 years) were defined by having no records of hospitalization in the national Swedish Hospital Discharge Register prior to the baseline examination, other than hospitalization due to normal deliveries or external injuries. MHO subjects were further compared to subjects with metabolically unhealthy obesity, MUO (n=2,630; mean age 60±7 years), and all non-obese individuals (n=24,591; mean age 58±8 years) in the cohort study. Moreover, prospective risk analyses for incident morbidity and mortality were carried out by Cox regression. Results Compared to MOU individuals (one-way ANOVA), MHO individuals were younger (58±7 years vs. 60±7 years, p=0.001) and more likely to be male (41.2% vs 37.1%, p=0.016). MHO individuals reported a significantly lower proportion of sedentary life style than MUO (17.4% vs. 21.9%, p=0.009), and were more likely to hold a university degree (13.4% vs. 9.4%, p=0.003). Furthermore, MHO individuals had significantly lower HbA1c (p=0.012), fasting plasma glucose (p=0.001) and triglyceride levels (p=0.011) as compared to their MOU counterparts. Cox-regression analysis adjusted for age, sex, smoking and blood pressure (follow-up time 20±6 years) showed both a significantly lower all-cause mortality risk for MHO individuals as compared to MUO (HR 0.74, 95% CI: 0.66–0.82; p=0.001), as well as lower total incident cardiovascular (CV) morbidity risk (HR 0.69, 95% CI: 0.60–0.80; p=0.001). Interestingly, when comparing MHO individuals to all non-obese individuals in the MDCS, there were no significant differences in neither mortality risk (p=0.9), nor incident CV morbidity risk (p=0.7). All-cause mortality risk Conclusion Compared to MUO individuals, MHO individuals presented with a higher level of education- and physical activity together with a more favorable lipid- and glucose profile. MHO individuals were at significantly lower prospective risk of total- and cardiovascular mortality during 20-years follow-up, as compared to MOU individuals. Notably, no significant differences could be seen in mortality and CV morbidity risks when comparing MHO subjects to all non-obese individuals in the total cohort. Acknowledgement/Funding The Research Council of Sweden and Skane University Hospital Funds and Foundations (Sweden)

Methylation age acceleration does not predict mortality in schizophrenia

Schizophrenia (SCZ) is associated with high mortality. DNA methylation levels vary over the life course, and pre-selected combinations of methylation array probes can be used to estimate “methylation age” (mAge). mAge correlates highly with chronological age but when it differs, termed mAge acceleration, it has been previously associated with all-cause mortality. We tested the association between mAge acceleration and mortality in SCZ and controls. We selected 190 SCZ cases and 190 controls from the Sweden Schizophrenia Study. Cases were identified from the Swedish Hospital Discharge Register with ≥5 specialist treatment contacts and ≥5 antipsychotic prescriptions. Controls had no psychotic disorder or antipsychotics. Subjects were selected if they had died or survived during follow-up (2:1 oversampling). Extracted DNA was assayed on the Illumina MethylationEPIC array. mAge was regressed on age at sampling to obtain mAge acceleration. Using Cox proportional hazards regression, the association between mAge acceleration and mortality was tested. After quality control, the following were available: n = 126 SCZ died, 63 SCZ alive, 127 controls died, 62 controls alive. In the primary analyses, we did not find a significant association between mAge acceleration and SCZ mortality (adjusted p > 0.005). Sensitivity analyses excluding SCZ cases with pre-existing cancer demonstrated a significant association between the Hannum mAge acceleration and mortality (hazard ratio = 1.13, 95% confidence interval = 1.04–1.22, p = 0.005). Per our pre-specified criteria, we did not confirm our primary hypothesis that mAge acceleration would predict subsequent mortality in people with SCZ, but we cannot rule out smaller effects or effects in patient subsets.

Use of Phosphodiesterase 5 Inhibitors Is Associated With Lower Risk of Colorectal Cancer in Men With Benign Colorectal Neoplasms

Phosphodiesterase 5 (PDE5) inhibitors have been proposed to have chemopreventative effects on colorectal cancer (CRC), although data are needed from population-based studies. We performed a nationwide cohort study to investigate the association between the use of PDE5 inhibitors and the risk of CRC in men with benign colorectal neoplasms. We identified men who received a diagnosis of benign colorectal neoplasm from July 2005 through March 2015 who were listed in the Swedish Hospital Discharge Register. We linked data with those from other national Swedish registers to obtain information about the prescription of PDE5 inhibitors and CRC diagnoses. Cox regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). A total of 4823 patients were prescribed PDE5 inhibitors during the study period; the incidence rate of CRC was 2.64 per 1000 person-years for men prescribed PDE5 inhibitors compared with 4.46 per 1000 person-years for men without a prescription. We found a significant negative association between PDE5 inhibitor use and risk of CRC (adjusted HR, 0.65; 95% CI, 0.49-0.85); the decreased risk of CRC was associated with an increased cumulative dose of PDE5 inhibitors (P= .003). PDE5 prescription was associated with greater reduction in risk of advanced-stage CRC (adjusted HR, 0.61; 95% CI, 0.37-1.00) than early-stage CRC (adjusted HR, 0.70; 95% CI, 0.50-0.98), but the difference was not significant. In a nationwide population-based study of men with a diagnosis of benign colorectal neoplasm in Sweden, we found evidence that use of PDE5 inhibitors is associated with a reduced risk of CRC. Further studies are needed to confirm the observed association.

Hospitalization rate in offspring of cancer survivors: a national cohort study

PurposeThe number of childbirths among cancer survivors continues to increase, but it is still largely unknown whether the children of cancer survivors might experience adverse health outcomes during the process of growing up.MethodsWe identified all individuals diagnosed with cancer between 1958 and 2015 from the Swedish Cancer Registry and linked them to the Swedish Medical Birth Register to identify their offspring born between 1997 and 2015. Up to 10 children, whose parents did not have a diagnosis of cancer, were matched with the study population according to date of birth and gender.ResultsBy linking with the Swedish Hospital Discharge Register, we found that the hospitalization rate was 15% higher in offspring of female cancer survivors, and 16% higher in offspring of male cancer survivors as compared to matched controls. Besides an increased risk of hospitalization due to malignant neoplasms (relative risk (RR) = 1.86, 99% CI 1.70–2.04) and benign neoplasms (RR = 1.48, 99% CI 1.18–1.86), a non-significant increased risk was found for hospitalization due to infectious and parasitic disease (RR = 1.09, 99% CI 0.98–1.21), diseases of the blood and blood-forming organs and certain disorders involving the immune mechanisms (RR = 1.33, 99% CI 0.98–1.80), and diseases of the circulatory system (RR = 1.05, 99% CI 0.98–1.12).ConclusionOur study suggests that children of cancer survivors might experience a significantly increased rate of hospitalization, which calls for further studies.Implications for Cancer SurvivorsCancer survivors might be aware that the risk of hospitalization due to various diseases might be higher in their children as compared to the normal population.

Socioeconomic circumstances and incidence of chronic obstructive pulmonary disease (COPD) in an urban population in Sweden

The association between socioeconomic circumstances and incidence of chronic obstructive pulmonary disease (COPD) was investigated in an urban population in Sweden. The study included all 40–89 year-old inhabitants in Malmö, Sweden (N = 117,479) without previous hospitalization due to COPD, who were followed over 14 years for COPD related hospital admissions. The Malmö Preventive Project (MPP) cohort (n = 27,358) with information on biological and lifestyle factors was also used to study the association between socioeconomic circumstances and COPD. The Swedish hospital discharge register was used to record incidence of COPD hospitalizations. A total of 2,877 individuals (47.5% men) were discharged from hospital with COPD as the primary diagnosis during follow-up in Malmö. Low annual income (hazard ratio (HR): 2.23; 95%CI: 1.97–2.53, P < 0.001) and rented (vs. self-owned) housing (HR: 1.41; 1.30–1.52, P < 0.001) were associated with a higher risk for COPD. In addition, compared to married subjects, divorced (HR: 1.61; 1.46–1.78, P < 0.001) and widowed (HR: 1.30; 1.16–1.46, P < 0.001) individuals had an increased risk for hospitalization due to COPD. Low income, low occupation and being divorced or widowed were similarly associated with COPD in the MPP cohort, after adjustments for smoking, FEV1, BMI, age and sex. However, socioeconomic circumstances were not associated with COPD in analyses restricted to never smokers. Low socioeconomic circumstances were associated with an increased risk of COPD after adjustments for biological and lifestyle risk factors including smoking status. However, this relationship was not significant in those who never smoked.

The impact of post-hepatectomy liver failure on mortality: a population-based study

Background: Post-hepatectomy liver failure (PHLF) is considered a main reason for death after major hepatectomy. The reported PHLF-related mortality differs largely and the data mainly originate from single centers.Aim: A retrospective, population-based register study was designed to evaluate the impact of PHLF on 90-day mortality after hepatectomy.Method: All patients who underwent liver resection in Sweden between 2005 and 2009 were retrospectively identified using the Swedish Hospital Discharge Registry. 30- and 90-day mortality were identified by linkage to the Registry of Causes of Death. Additional clinical data were obtained from the medical charts in all seven university hospitals in Sweden. PHLF was defined according to Balzan criteria (Bilirubin >50 µg/L and international normalized ratio >1.5) on postoperative day 5.Results: A total of 2461 liver resections were performed (2194 in university hospitals). 30- and 90-day mortality were 1.3% and 2.5%, respectively. 90-day mortality at university hospitals was 2.1% (n = 46). In 41% (n = 19) of these patients, PHLF alone or in combination with multi-organ failure was identified as cause of death. Between the PHLF and non-PHLF group, there was no significant difference regarding age, sex, American Society of Anesthesiologists-classification, or preoperative chemotherapy. Cholangiocarcinoma as indication for surgery, need for vascular reconstruction and an extended resection were significantly overrepresented in the PHLF-group. Between groups, the incidence of 50:50 criteria differed significantly already on postoperative day 3.Conclusion: Overall mortality is very low after hepatectomy in Sweden. PHLF represents the single most important cause of death even in a population-based setting.

Hospitalization rate of paroxysmal supraventricular tachycardia in Sweden

Introduction: The hospitalization rate of paroxysmal supraventricular tachycardia (PSVT) in a nationwide study is not established. We determined age- and sex-specific hospitalization rates and time trends for hospitalized PSVT in the Swedish population between 1987 and 2010.Methods: This nationwide study is based on the Swedish Hospital Discharge Register. The patients with first PSVT diagnoses between January 1987 and December 2010 were identified.Results: A total of 42,765 individuals with PSVT were diagnosed (mean age 60 years; 44% males). The overall age- and sex-adjusted hospitalization rate was 20 per 100,000 person-years. The hospitalization rate increased with advancing age with highest hospitalization rates in individuals aged 80–84 years (67.12 per 100,000 person-years) and did not change significantly over time. A total of 20,011 (46.8%) patients had “lone” PSVT without any comorbidities. Lone PSVT patients were younger than PSVT patients with comorbidities (mean age 54 vs. 67 years, p = .0002).Conclusions: This study showed a slight preponderance for females and stable hospitalization rate of PSVT over time; the hospitalization rate increased with age. A high proportion of PSVT patients had no comorbidities. They were affected at a younger age than patients with comorbidities, which suggests an inherent predisposition.Key messagesThis study represents the first extensive and nationwide hospitalization study of PSVT. Hospitalization is highest in old age but a bimodal pattern was observed with a small peak in the first years of life. Patients with lone PSVT are younger than those with comorbidities; which suggests an inherent predisposition.

Characteristics and prognosis of healthy severe obesity (HSO) subjects - The Malmo Preventive Project

BackgroundThe characteristics and prognosis of healthy obesity (HO) still remain unclear. We aimed to examine the characteristics of healthy severe obesity (HSO), defined by a novel approach, with a focus on self-reported physical activity (PA) and a genetic risk score for type 2 diabetes (GRS DM2). MethodsA cross-sectional analysis was carried out in a subsample of severly obese subjects (BMI≥35 kg/m2; n = 809) selected from the population-based Malmo Preventive Project (MPP). Subjects with HSO (n = 57) were defined by having no records of hospitalisation in the Swedish Hospital Discharge Register during a time period of 33.4 ± 3.9 years between baseline (1974–1992) and the end of follow-up (31st of December 2014). They were compared to subjects with unhealthy severe obesity (USO; n = 752), as well as age- and sex-matched non-obese controls (n = 1618). ResultsSubjects with HSO had a significantly lower GRS DM2 (HSO 40.4 ± 3.7 vs. USO 41.8 ± 3.8, p = 0.007). Compared to subjects with USO, the HSO subjects reported significantly more leisure-time physical activity, PA (p = 0.016). There were no significant differences between HSO and USO subjects in the distribution of fat mass or obesity-associated gene phenotypes (FTO gene; variant rs9939609; p = 0.8). ConclusionHigher PA and lower GRS DM2 might be protective factors against all-cause hospitalisation in subjects with severe obesity. These findings support the concept of HO being fat but fit. Still, it remains unclear whether higher PA is causally related to HSO, and which role environmental factors such as PA play in the interaction with genetic factors such as GRS DM2.

Exposure to whole-body vibration and hospitalization due to lumbar disc herniation

ObjectiveThe aim was to examine if exposure to whole-body vibration (WBV) increases the risk for hospitalization due to lumbar disc herniation.MethodsThe study basis is a cohort of 288,926 Swedish construction workers who participated in a national occupational health surveillance programme from 1971 until 1992. Job title, smoking habits, body weight, height and age were registered at the examinations. Assessment of WBV were made for each of the constituent occupations by constructing a job-exposure matrix (JEM). Exposure to WBV was graded on a scale from 0 to 5. In addition, the occurrence of hospitalization due to lumbar disc herniation from January 1st 1987 until December 31st 2010 was collected from a linkage with the Swedish Hospital Discharge Register. Poisson regressions were used to estimate relative risk with 95 percent confidence intervals (95% CI), adjusting for age, height, weight and smoking, using white-collar workers and foremen as a reference group.ResultsThere was an increased risk for hospitalization due to lumbar disc herniation for workers in the construction industry exposed to medium to high WBV compared to white-collar workers and foremen 1.35 (1.12–1.63). When restricting the analyses to include workers 30–49 years of age at the time of the hospital admission the risk was 1.69 (95% CI 1.29–2.21).ConclusionThis study further supports that occupational exposure to whole-body vibration increases the risk for hospitalization due to lumbar disc herniation.

Congenital malformation in offspring of female cancer survivors: a national cohort study.

Current evidence on congenital malformations in the offspring of cancer survivors is largely inconsistent. Therefore, through this study we aimed to explore the prevalence of congenital malformations in the offspring of cancer survivors. To this end, female cancer survivors were identified from the Swedish Cancer Register and were further linked to the Swedish Medical Birth Register and Hospital Discharge Register to identify congenital malformation in their children at birth or during adulthood between 1987 and 2010. Multivariate logistic regression was used to estimate odds ratios and 95% confidence intervals for the association between congenital malformation and maternal cancer diagnosis. A total of 816 congenital malformations were noted among 9266 children of maternal cancer survivors, and the rate was 8.8%, whereas the rate in the general population was 7.7%. After adjusting for some confounding factors, we found that the risk for congenital malformation in children of cancer survivors was significantly increased with an odds ratio of 1.11 and 95% confidence interval of 1.04-1.20 as compared with that in controls. The increased risk was largely consistent irrespective of maternal age at diagnosis of cancer. The risk for congenital malformation was increased among offspring of female cancer survivors, which calls for further attention directed toward those cancer survivors who plan to have children.