Rickard Ljung

Weekend Versus Weekday Admission and Stroke Outcome in Sweden From 1968 to 2005

To the Editor:nnWe read with great interest the article by Saposnik et al.1 The authors analyzed data from stroke patients admitted to Canadian acute care hospitals between April 1, 2003, and March 31, 2004, and concluded that stroke patients admitted on weekends had a higher mortality than did patients admitted on weekdays. To shed further light on this issue we here …

Insulin glargine use and short-term incidence of malignancies — a three-year population-based observation

Abstract Aims/hypothesis. To further investigate the association of cancer occurrence with the use of insulin glargine. Methods. We followed 114 838 individuals using insulin between 1 July and 31 December 2005. From 1 January 2006 to 31 December 2008, we noted the occurrence of malignancies (cohort I). Insulin users between 1 July and 31 December 2006 were followed for the occurrence of malignancies in 2007 and 2008 (cohort II). Users of insulin during three consecutive six-month periods from 1 July 2005 to 31 December 2006 were followed for the occurrence of malignancies in 2007 and 2008 (cohort III). The Prescribed Drug Register, the Cancer Register, and the Causes of Death Register were used to obtain information on targeted person-time and outcome. We retrieved variables reflecting potential confounding factors from the Swedish National Diabetes Register, the Prescribed Drug Register, the Patient Register, the Medical Birth Register and the National Education Register. With Poisson regression we evaluated the association between insulin use and malignancy outcome with adjustment for confounders. Results. The adjusted incidence rate ratio (and 95% confidence interval) for women who used insulin glargine alone compared with those who used other types of insulin, was 1.60 (1.10–2.32) for breast cancer but included 1.0 for malignancy outcomes other than breast cancer for men and women when analyzing cohort I with follow-up in 2006–2008. For cohort II and III the corresponding incidence rate ratios were 1.38 (0.87–2.18), and 0.87 (0.41–1.85), respectively. Conclusion/interpretation. We do not see an increased risk during 2008 for breast cancer in the insulin glargine group. We need data for additional years before we can state with reasonable certainty that the increase in breast cancer incidence that we observed in Sweden in 2006 and 2007 was due to a random fluctuation or whether there is an association with the use of insulin glargine.

Juvenile delinquency, social background and suicide—a Swedish national cohort study of 992 881 young adults

BACKGROUNDnAs the suicide rates in young adults do not show a clear decline, it is important to elucidate possible risk factors. Juvenile delinquency has been pointed out as a possible risk behaviour.nnnMETHODSnThis register-based cohort study comprises the birth cohorts between 1972 and 1981 in Sweden. We followed 992,881 individuals from the age of 20 years until 31 December 2006, generating 10 210 566 person-years and 1482 suicides. Juvenile delinquency was defined as being convicted of a crime between the ages of 15 and 19 years. Estimates of risk of suicide were calculated as incidence rate ratio (IRR) with 95% confidence intervals (CIs) using Poisson regression analysis with adjustment for potential confounding by their own and their parents mental illness or substance abuse, parental education, single parenthood, social assistance, adoption and foster care.nnnRESULTSnAmong females, 5.9%, and among males, 17.9%, had at least one conviction between the ages 15 and 19 years. In the fully adjusted model, females with one conviction had a suicide risk of 1.7 times higher (95% CI 1.2-2.4), the corresponding IRR for men was 2.0 (95% CI 1.7-2.4) and 5.7 (95% CI 2.5-13.1) and 6.6 (95% CI 5.2-8.3), for women and men with five or more convictions. The effect of severe delinquency on suicide was independent of parental educational level.nnnCONCLUSIONSnThis study supports the hypothesis that individuals with delinquent behaviour in late adolescence have an increased risk of suicide as young adults. Regardless of causality issues, repeated juvenile offenders should be regarded by professionals in health, social and correctional services who come into contact with this group as a high-risk group for suicide.

Widowhood and the risk of psychiatric care, psychotropic medication and all-cause mortality: A cohort study of 658,022 elderly people in Sweden

Objectives: To study the effect of widowhood on the risk of psychiatric care, psychotropic medication and mortality, and to study if the effect is modified by educational level. Method: A nationwide, register-based cohort study. All married or widowed individuals aged 75 and older who were alive and registered in Sweden on 31 December 2004 and still registered on 31 December 2005. A total of 658,022 individuals were included in the study and followed in 2006. Odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated. Results: Loss of spouse increased the risk of outpatient psychiatric visits, psychotropic medication and all-cause mortality. Prescribed psychotropic medication was more common among those newly bereaved, adjusted OR of 1.46 (95% CI 1.41–1.50), compared to those married. For those widowed for a longer period, the corresponding estimate was 1.12 (95% CI 1.11–1.14). The OR for all-cause mortality was 1.18 (95% CI 1.11–1.26). The analyses also indicated different effects on inpatient care depending on educational level. Conclusion: Loss of spouse increases the risk of people getting psychiatric care, both for severe and minor psychiatric conditions. The effect seems to differ depending on educational level. Further studies are needed to disentangle the mechanism behind the effects of each measurement of psychiatric conditions and how these are affected by educational level.

Insulin glargine use and short-term incidence of breast cancer - a four-year population-based observation.

1National Board of Health and Welfare, Stockholm, Sweden, 2Upper Gastrointestinal Research, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden, 3Equity and Health Policy, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden, 4Division of Clinical Cancer Epidemiology, Department of Oncology, The Sahlgrenska Academy, Onkologiskt Centrum, Gothenburg, Sweden, 5Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden, 6Diabetes Centre, Sahlgrenska University Hospital, Gothenburg, Sweden, 7Nordic School of Public Health, Gothenburg, Sweden and 8National Diabetes Register, Register Center, Västra Götaland Region, Sweden

Systematic underreporting of the population-based incidence of pancreatic and biliary tract cancers

Abstract Background. Incidence rates of cancers of the pancreas and biliary tract, typically derived from cancer registers, have been reported to be decreasing. This study tested whether pancreatic and biliary tract cancers are underreported in the Swedish Cancer Register (CR). Methods. The concordance of pancreatic and biliary tract cancer diagnoses in 1990–2009 between CR and the Swedish Patient Register (PR) were evaluated through record linkage. To further assess the completeness of these cancer diagnoses in both CR and PR, record linkage was also made to the Swedish Causes of Death Register (DR). Results. A total of 31 067 cases of pancreatic cancer and 14 273 cases of biliary tract cancer were identified in CR or PR. Altogether, 44% of the pancreatic cancers and 44% of the biliary tract cancers were registered in PR only, and not in CR. The concordance between CR and PR declined from 63% in the years 1990–1994 to 44% in 2005–2009 for pancreatic cancer. The corresponding figures for biliary tract cancer were 60% and 37%. This decline in concordance was also observed with increasing age, e.g. the concordance between CR and PR for pancreatic cancer declined from 62% in patients < 60 years to 36% among patients ≥ 80 years. The corresponding figures for biliary tract cancer were 52% and 38%. Conclusion. There is an overwhelming underreporting of pancreatic and biliary tract cancers within the Swedish Cancer Register, which has increased during recent years. The reported decreasing incidence rates for pancreatic and biliary tract cancers might therefore be incorrect.

Thyroxin substitution and open-angle glaucoma: a nationwide register-based study on filled prescriptions.

The issue of the possible association between hypothyroidism and glaucoma is well studied but still remains controversial. Some previous studies have found a correlation between hypothyroidism and open-angle glaucoma1–3 whereas others have not.4–6 Our aim was to test the hypothesis that hypothyroidism is associated with open-angle glaucoma in a large nationwide register-based cohort study on filled prescriptions, a design unique to the existing literature on the subject.nnAll 2u2008088u2008297 residents in Sweden aged 60–89 years who were alive during the period 31 December 2007 to 31 December 2008 constituted our source population. We used the unique personal identity number, assigned to each Swedish resident (about 9 million in total), to link information from three population-based registers of almost complete coverage and high quality—the Prescribed Drug Register, the Cause of Death Register and the Register of the Total Population.nnThe Swedish Prescribed …

Twelve tips for conducting a postgraduate course on study design and study protocol writing for the medical profession

Background: It is desirable to use a methodological approach of the highest scientific quality when planning and conducting valid research. However, several studies have shown that the biostatistical and epidemiological knowledge of academically active health care professionals is far below the desired level. Aim: To outline an approach to conducting a postgraduate course in clinical study design and study protocol writing. Method: We offer 12 tips based on critical reflection of our experience of conducting and continuously improving a course in study design repeatedly over several years, combined with evidence from the literature on pedagogical approaches. Result: The tips are organized in chronological order so that a course director will be able to develop a similar course. Conclusion: Combining the results of our critical reflection with evidence from the literature has allowed us to develop a successful approach to running courses in study design and study protocol writing. We hope that our extensive experience in conducting this course, as reflected by the 12 tips, will support and inspire others planning similar courses.

Cancer incidence in persons with type 1 diabetes: a five-country study of 9,000 cancers in type 1 diabetic individuals

Aims/hypothesisAn excess cancer incidence of 20–25% has been identified among persons with diabetes, most of whom have type 2 diabetes. We aimed to describe the association between type 1 diabetes and cancer incidence.MethodsPersons with type 1 diabetes were identified from five nationwide diabetes registers: Australia (2000–2008), Denmark (1995–2014), Finland (1972–2012), Scotland (1995–2012) and Sweden (1987–2012). Linkage to national cancer registries provided the numbers of incident cancers in people with type 1 diabetes and in the general population. We used Poisson models with adjustment for age and date of follow up to estimate hazard ratios for total and site-specific cancers.ResultsA total of 9,149 cancers occurred among persons with type 1 diabetes in 3.9 million person-years. The median age at cancer diagnosis was 51.1xa0years (interquartile range 43.5–59.5). The hazard ratios (HRs) (95% CIs) associated with type 1 diabetes for all cancers combined were 1.01 (0.98, 1.04) among men and 1.07 (1.04, 1.10) among women. HRs were increased for cancer of the stomach (men, HR 1.23 [1.04, 1.46]; women, HR 1.78 [1.49, 2.13]), liver (men, HR 2.00 [1.67, 2.40]; women, HR 1.55 [1.14, 2.10]), pancreas (men, HR 1.53 [1.30, 1.79]; women, HR 1.25 [1.02,1.53]), endometrium (HR 1.42 [1.27, 1.58]) and kidney (men, HR 1.30 [1.12, 1.49]; women, HR 1.47 [1.23, 1.77]). Reduced HRs were found for cancer of the prostate (HR 0.56 [0.51, 0.61]) and breast (HR 0.90 [0.85, 0.94]). HRs declined with increasing diabetes duration.ConclusionType 1 diabetes was associated with differences in the risk of several common cancers; the strength of these associations varied with the duration of diabetes.

FC08-02 - Severity of mental disorder and the risk of all-cause, avoidable, ischemic heart disease, violent and suicide mortality

Introduction There are indications that psychiatric patients do not receive adequate treatment of their somatic diseases. Objectives To evaluate the effect of mental disorder on the risk of mortality. Aims To study whether severity of psychiatric disease increases the risk of mortality. Methods A register-based cohort study comprising all individuals alive and registered in Sweden in 2004 and 2005 aged 20–64. We followed 5,181,743 individuals with respect to mortality 2006 and 2007, generating 10,261,263 person-years and 24,475 deaths. Psychiatric patients were defined as those treated with a main diagnosis of psychiatric disease within the last five years and were classified according to type of mental disorder: psychoses, depression/anxiety, substance abuse, and other psychiatric diagnoses. We studied all cause mortality, mortality from ischemic heart disease, suicide, violent deaths, smoking related cancer and policy-related and health care-related avoidable mortality. Estimates of risk of mortality were calculated as incidence rate ratio (IRR) with 95% confidence intervals (CI) using Poisson Regression Analysis. Results Patients with schizophrenia or other psychosis in general had the highest mortality for most mortality outcomes. For both women and men, those treated for substance abuse had the highest all-cause mortality risk (Women: IRRxa0=xa012.56 (95% CIxa0=xa010.82–14.57); Men: IRRxa0=xa09.38 (95% Cxa0=xa08.73–10.08). For all psychiatric diseases and for all mortality outcomes those on social benefits had a higher mortality. Conclusion Psychiatric patients have a higher overall mortality and cause-specific mortality. The more severe the psychiatric disease the higher is the risk of mortality even after disregarding violent deaths and suicide.