Swedish Residents Research Articles

Risk of Travel-Associated Typhoid and Paratyphoid Fevers in Various Regions

Although enteric fever (typhoid and paratyphoid fevers) is a major global public health problem, comparable data on the risks of contracting travel-associated enteric fever in various regions of the world are scarce. From the Swedish database on notifiable communicable diseases, we retrieved all case records from 1997 to 2003 on typhoid and paratyphoid fevers. The data set was compared with data on travel patterns obtained from a comprehensive travel database with information from interviews with more than 16,000 Swedish residents with recent overnight travel outside Sweden. The overall risk of being notified with enteric fever after travel was 0.42 in 100,000 travelers. The highest risk for typhoid fever was seen in travelers from India and neighboring countries (41.7 in 100,000), the Middle East (5.91 in 100,000), and Central Africa (3.33 in 100,000), whereas the risk was comparatively low in East Asia (0.24 in 100,000). Almost the same risk areas stood out for paratyphoid fever: India and neighbors (37.5 in 100,000), the Middle East (3.64 in 100,000), and East Africa (3.33 in 100,000). The epidemiology of paratyphoid fever was considerably affected by a large outbreak of paratyphoid B in a Turkish tourist resort in 1999. The youngest children were at highest risk for typhoid fever (odds ratio 44.2), whereas youths ages 7 to 18 years were at highest risk for paratyphoid fever (odds ratio 9.7). Detailed risk data for enteric fever after travel could form the basis for travel advice. Vaccination against typhoid fever should always be considered for travelers to the Indian subcontinent, the Middle East, and Africa but should not routinely be given to travelers to the Malay Peninsula.

The comparative burden of salmonellosis in the European Union member states, associated and candidate countries

BackgroundSalmonella is an infectious agents causing numerous cases of illness each year, and thereby having significant economic impact. Using returning Swedish travellers we estimated the burden of salmonellosis in different European countries.MethodsFrom the Swedish database on notifiable communicable diseases 15,864 cases with travel-associated salmonellosis acquired in Europe from 1997–2003 were retrieved. These cases were compared to a dataset from the same years on 14,171 randomly selected Swedish residents, with a history of recent overnight travel in Europe. Distribution of salmonellosis in returning travellers and the distribution of Salmonella Enteritidis was analysed for different member states in the European Union, associated and candidate countries. The risk of being notified with a salmonella infection after return from each European country/region was calculated, and compared with official reporting data rom these countries. Using Norway as reference country, we could 1) construct comparable incidence estimates and 2) calculate the "under-reporting" in each country compared to Norway.ResultsThe highest burden of salmonellosis was estimated for Bulgaria (2741/100,000), followed by Turkey with 2344/100 000 and Malta with 2141/100 000. S. Enteritidis is the dominating serotype, 66.9 % of all cases and phage type 4 accounts for 37.5 % of the S. Enteritidis casesConclusionUsing returning tourists as a sentinel population can provide a useful base for comparison of disease burdens in different countries/regions. Focusing prevention of salmonellosis to prevention of egg and poultry associated S. Enteritidis infection will have a major impact from a public health perspective and will significantly lower the burden of disease in most European countries.

Perfluorinated chemicals in relation to other persistent organic pollutants in human blood

In order to evaluate blood levels of some perfluorinated chemicals (PFCs) and compare them to current levels of classical persistent organic pollutants (POPs) whole blood samples from Sweden were analyzed with respect to 12 PFCs, 37 polychlorinated biphenyls (PCBs), p, p′-dichlorodiphenyl-dichloroethylene (DDE), hexachlorobenzene (HCB), six chlordanes and three polybrominated diphenyl ethers (PBDEs). The median concentration, on whole blood basis, of the sum of PFCs was 20–50 times higher compared to the sum of PCBs and p, p′-DDE, 300–450 times higher than HCB, sum of chlordanes and sum of PBDEs. Estimations of the total body amount of PFCs and lipophilic POPs point at similar body burdens. While levels of for example PCBs and PBDEs are normalized to the lipid content of blood, there is no such general procedure for PFCs in blood. The distributions of a number of perfluorinated compounds between whole blood and plasma were therefore studied. Plasma concentrations were higher than whole blood concentrations for four perfluoroalkylated acids with plasma/whole blood ratios between 1.1 and 1.4, whereas the ratio for perflurooctanesulfonamide (PFOSA) was considerably lower (0.2). This suggests that the comparison of levels of PFCs determined in plasma with levels determined in whole blood should be made with caution. We also conclude that Swedish residents are exposed to a large number of PFCs to the same extent as in USA, Japan, Colombia and the few other countries from which data is available today.

The updated Swedish family-cancer database used to assess familial risks of prostate cancer during rapidly increasing incidence

The Swedish Family-Cancer Database has been used for some 10 years in the study of familial risks at all common sites. In the present paper we describe some of the main features of version VII of this Database, assembled in year 2006. This update included all residents in Sweden born or immigrated in 1932 and later (offspring) with their biological parents, a total of 11.5 million individuals. Cancer cases were retrieved from the Swedish Cancer Registry from years 1958 to 2004, including over 1.2 million first and multiple primary cancers and in situ tumours. We show one application of the Database in the study of familial risks in prostate cancer, with special reference to the modification of familial risk at the time of about 50% increase in incidence due to prostate specific antigen (PSA) screening. The familial risks for prostate cancer were 1.92 for sons of affected fathers, 3.03 for brothers and 5.44 for men with an affected father and an affected brother. Familial risk for prostate cancer according to the time since the first family member was diagnosed showed significant increases for two family members being diagnosed in the same year compared to 5+ years apart. Increased surveillance and the availability of PSA screening are the likely reasons for the overestimated familial relative risk shortly after the first diagnosis. This lead time bias should be considered in clinical counselling.

Prevention of travel-related infectious diseases: Knowledge, practices and attitudes of Swedish travellers

More Swedish residents travel to countries where they are at risk for contracting malaria, hepatitis, and other serious travel-related diseases. To safeguard the public's health, it is important to determine if travellers accurately perceive health risks and take appropriate preventative measures before and during their trips. This study examined travel health knowledge, attitudes and practices among Swedish residents traveling to destinations with risk of malaria and hepatitis. Self-administered anonymous questionnaires were distributed to Swedish residents (n=957) waiting to board intercontinental flights at the Stockholm-Arlanda International Airport. A majority of travellers sought general information (74%) and travel health advice (59%) prior to departure. Most perceived vaccination as safe and effective, but only 40% and 3% of travellers reported adequate vaccine coverage against hepatitis A or hepatitis B, respectively. Although most did not know the actual malaria risk at the destination, 97% of persons flying to high-risk areas were carrying malaria medication. The study results were in line with those found in surveys conducted in other countries, and demonstrate need for further health education among travellers to risk destinations. Efforts should focus on reaching more travellers, providing clear information and improving compliance with recommended travel health advice.

How much transport can the climate stand?—Sweden on a sustainable path in 2050

In this paper an image of a sustainable transport system for Sweden in 2050 is outlined. The emissions per capita in this image may be generalized to a global population of 9 billions, and still be consistent with a stabilization of the carbon dioxide concentration at 450 ppm (parts per million). Swedish transport energy use per capita is 4.6 MWh in the image, compared to 12.5 MWh at present. The aim is, first, to widen the perspective of sustainable transport futures and, second, to provide a basis for present decisions in areas characterized by a high inertia, e.g. regarding infrastructure and the built-up environment. All transport generated by the lifestyles of Swedish residents are included. The reduction of energy use in the image is primarily achieved by an introduction of energy efficient vehicles and a conscious combination of IT-services and urban planning. The latter aims at increasing functional accessibility while reducing commuting. A prioritization of leisure travel to structurally-enforced travel gives the possibility to increase leisure travel per capita by one third. However, this is contingent on a 50% reduction of per capita car travel in cities. Given the set-up target, it may be concluded that the need for new arterial road capacity in cities often is negligible, even with a considerable population increase.

Travel-associated non-typhoidal salmonellosis: geographical and seasonal differences and serotype distribution

The Swedish database on notifiable communicable diseases was used to identify 24 803 cases of travel-associated non-typhoidal salmonellosis from the period 1997-2003. Serotype data were available for 24 358 (98.2%) of these cases, which were compared with a data set from the same period of 16 255 randomly selected Swedish residents with a history of recent overnight travel outside Sweden. The highest risk of disease was seen in travellers returning from East Africa (471/100 000 travellers; 95% CI 294-755), or the Indian subcontinent (474/100 000; 95% CI 330-681). Children aged 0-6 years were at higher risk than travellers of other ages (OR 2.4; 95% CI 2.1-2.8). Some distinct seasonal patterns could be distinguished, with highest (adjusted) risk in December in East Asia, and in August in Europe. Marked geographical differences in serotype distribution were noted. Salmonella Enteritidis was especially dominant in Europe, but was much less common in Africa, Asia and America, where the variety of circulating serotypes was greater. Overall, the two data sets provided important information on travel risks which are also likely to apply to travellers from other western countries.

Knee surgery costs in football, floor ball, European team handball and ice hockey

The purpose of this study was first, to identify the health costs of knee surgery related to different sports (football, floor ball, European team handball and ice hockey) among players at competitive level in Stockholm 1997. Information was retrieved from three different databases, one containing information on all players in different sports, another one containing information on all surgery performed at S:t Gorans Hospital, Stockholm, and a third one containing information on all surgery performed in Stockholm. The National Registration Number (NRN) was used to identify the patients. The NRN is a unique personal identifier assigned to all Swedish residents, which allows linkage between different registers and databases. In Stockholm in 1997, 6781 surgical procedures related to the knee were performed at a cost of SEK (Swedish Crowns) 39,026,657. On players in all studied sports, 762 knee surgical procedures were performed on 657 patients in Stockholm at a cost of SEK 4,884,076. At S:t Gorans Hospital, 319 knee surgical procedures were performed on 288 patients, and 293 (92%) of these were directly related to sport participation. It was also found that only 74% of anterior cruciate ligament injuries that resulted in a surgical intervention were reported to the insurance company. The average cost for knee surgery in the studied sports was low. Knee surgery costs for European team handball players were the highest compared with other sports studied.

Regional risks and seasonality in travel-associated campylobacteriosis

BackgoundThe epidemiology of travel-associated campylobacteriosis is still largely unclear, and various known risk factors could only explain limited proportions of the recorded cases.MethodsUsing data from 28,704 notifications of travel-associated campylobacteriosis in Sweden 1997 to 2003 and travel patterns of 16,255 Swedish residents with overnight travel abroad in the same years, we analysed risks for travel-associated campylobacteriosis in 19 regions of the world, and looked into the seasonality of the disease in each of these regions.ResultsThe highest risk was seen in returning travellers from the Indian subcontinent (1,253/100,000 travellers), and the lowest in travellers from the other Nordic countries (3/100,000 travellers). In Africa, large differences in risk between regions were noted, with 502 /100,000 in travellers from East Africa, compared to 76/100,00 from West Africa and 50/100,000 from Central Africa. A distinct seasonal pattern was seen in all temperate regions with peaks in the summer, while no or less distinct seasonality was seen in tropical regions. In travellers to the tropics, the highest risk was seen in children below the age of six.ConclusionsData on infections in returning travellers together with good denominator data could provide comparable data on travel risks in various regions of the world.

Social adversity contributes to high morbidity in psychoses in immigrants – a national cohort study in two generations of Swedish residents

Recent reports have indicated that immigrants have an elevated risk of schizophrenia as well as an increasing tendency for social exclusion. The aim of this study was to compare rates of schizophrenia and other psychoses in immigrants and their children of different ethnic groups with the majority population in Sweden in relation to social adversity. The study population consists of a national cohort of 1.47 million adults (born 1929-1965) and 1.16 million children and youth (born 1968-1979) in family households from the national census of 1985. Multivariate Cox regression analyses was used to study hospital discharge data during 1991-2000 in relation to socio-economic household indicators from 1985 and 1990 (single adult household, adults having received social welfare, parental unemployment, urban residency, housing and socio-economic status). First as well as second generation immigrants had higher age and sex adjusted risk ratios for schizophrenia as well as for other psychoses (RRs 1.4-3.1 and 1.0-2.0 respectively) compared with the Swedish majority population. These risk ratios decreased considerably after adjusting for socio-economic indicators, for all groups, but particularly for the non-European immigrants. However, an elevated risk still remained in the Finnish and Eastern and Southern European study groups. A higher risk of schizophrenia and psychoses was found in two generations of immigrants of diverse ethnicity. The results indicate that social adversity contributes to the higher risk.

Implementing a public web based GIS service for feedback of surveillance data on communicable diseases in Sweden.

BackgroundSurveillance data allow for analysis, providing public health officials and policy-makers with a basis for long-term priorities and timely information on possible outbreaks for rapid response (data for action). In this article we describe the considerations and technology behind a newly introduced public web tool in Sweden for easy retrieval of county and national surveillance data on communicable diseases.MethodsThe web service was designed to automatically present updated surveillance statistics of some 50 statutory notifiable diseases notified to the Swedish Institute for Infectious Disease Control (SMI). The surveillance data is based on clinical notifications from the physician having treated the patient and laboratory notifications, merged into cases using a unique personal identification number issued to all Swedish residents. The web service use notification data from 1997 onwards, stored in a relational database at the SMI.ResultsThe web service presents surveillance data to the user in various ways; tabulated data containing yearly and monthly disease data per county, age and sex distribution, interactive maps illustrating the total number of cases and the incidence per county and time period, graphs showing the total number of cases per week and graphs illustrating trends in the disease data. The system design encompasses the database (storing the data), the web server (holding the web service) and an in-the-middle computer (to ensure good security standards).ConclusionsThe web service has provided the health community, the media, and the public with easy access to both timely and detailed surveillance data presented in various forms. Since it was introduced in May 2003, the system has been accessed more than 1,000,000 times, by more than 10,000 different viewers (over 12.600 unique IP-numbers).

Performance of the Swedish SF-36 version 2.0.

To evaluate the performance of the first non-English (Swedish) SF-36 version 2.0 (V2) regarding scaling assumptions, reliability and validity, with special emphasis on the effects of extending the response scales of the two role functioning scales, role physical (RP) and role emotional (RE), from a dichotomous to a five-step format. Questionnaires were mailed to a non-stratified, random national sample of 3000 18-75 year old Swedish residents in 1998-1999. Methods traditionally used in evaluating the original US SF-36 version 1.0 (V1) and other international versions were applied. A total of 73% of the questionnaires were returned. Scaling assumptions were satisfactorily met and generally enhanced compared with V1, particularly regarding the role functioning scales. Floor/ceiling effects were reduced and reliability estimates increased for the role scales. The factor structure was replicated and the relative validity of the role scales as measures of their components increased. Overall, the tests of the criterion-based validity using known groups comparisons produced results supporting hypotheses: scales from the physical domain distinguished best between groups expected to differ in physical health; and scales comprising the mental domain distinguished best between groups expected to differ in mental health. Furthermore, hypothesized differences in mean scale scores as a function of age and social risk factors were confirmed. The changes to the response formats of the role functioning scales have improved their precision, reliability and validity without jeopardizing the underlying structure of the original SF-36. These changes will likely further enhance the responsiveness of the SF-36.

Inequality in access to coronary revascularization in Sweden

Objectives—To investigate social and gender equality in access to coronary revascularization for those treated for coronary heart disease in Sweden between 1991 and 2000.Design—All Swedish residents between 25 and 74 years old with a hospital stay for coronary heart disease were eligible for the study, in total about 153 000 persons. The Swedish Hospital Discharge Register from 1988 through 2000 was used to define the study population. Poisson regression analyses were used to estimate the effect of socio‐economic status on the likelihood for coronary artery bypass grafting (CABG) within 2 years. In the analysis of gender differences, the likelihood for percutaneous coronary intervention (PCI) was also included.Results—Males were 1.5 times more likely to undergo revascularization procedures than females even after adjusting for confounding factors and the fact that women are less eligible for interventions. The analyses also showed significant socio‐economic inequalities in access to CABG among men, but not among women.Conclusions—There are gender and socio‐economic inequalities in access to cardiac procedures in Sweden.

Neuropsychotherapeutics often used among elderly residents in Sweden

Neuropsychotherapeutics often used among elderly residents in Sweden

Absence of association between organic solvent exposure and risk of chronic renal failure: a nationwide population-based case-control study.

Exposure to organic solvents has been suggested to cause or exacerbate renal disease, but methodologic concerns regarding previous studies preclude firm conclusions. We examined the role of organic solvents in a population-based case-control study of early-stage chronic renal failure (CRF). All native Swedish residents aged 18 to 74 yr, living in Sweden between May 1996 and May 1998, formed the source population. Incident cases of CRF in a pre-uremic stage (n = 926) and control subjects (n = 998), randomly selected from the study base, underwent personal interviews that included a detailed occupational history. Expert rating by a certified occupational hygienist was used to assess organic solvent exposure intensity and duration. Relative risks were estimated by odds ratios (OR) in logistic regression models, with adjustment for potentially important covariates. The overall risk for CRF among subjects ever exposed to organic solvents was virtually identical to that among never-exposed (OR, 1.01; 95% confidence interval [CI], 0.81 to 1.25). No dose-response relationships were observed for lifetime cumulative solvent exposure, average dose, or exposure frequency or duration. The absence of association pertained to all subgroups of CRF: glomerulonephritis (OR, 0.96; 95% CI, 0.68 to 1.34), diabetic nephropathy (OR, 1.02; 95% CI, 0.74 to 1.41), renal vascular disease (OR, 1.16; 95% CI, 0.76 to 1.75), and other renal CRF (OR, 0.92; 95% CI, 0.66 to 1.27). The results from a nationwide, population-based study do not support the hypothesis of an adverse effect of organic solvents on CRF development, in general. Detrimental effects from subclasses of solvents or on specific renal diseases cannot be ruled out.

Illicit drug abuse in second-generation immigrants: a register study in a national cohort of Swedish residents.

This study investigates ethnic and socioeconomic risk factors for hospital admissions related to illicit drug abuse in second-generation immigrants in Sweden. Cox analyses of proportional hazards were used to estimate the relative risk of sociodemographic covariates in analyses of register data on hospital admissions because of illicit drug abuse during 1990-99. The study population was a national cohort of 1.25 million residents (aged 10-30 years). Second-generation immigrants had two- to three fold higher age and sex-adjusted relative risks (RRs) for hospital admissions because of illicit drug use compared with the Swedish majority population with a limited variation between different ethnic groups. The RRs decreased greatly after the model was adjusted for socioeconomic indicators of the childhood household. Inter-country adoptees had the highest risk for hospital admission related to illicit drug abuse of all study groups after adjustment for sociodemographic variables (RR 2.8). Second-generation immigrants are at particular risk for illicit drug abuse in Sweden. Adverse socioeconomic living conditions are very important in explaining this high risk.

Creating Narratives of Place and Identity in “Little Sweden, U.S.A.”

In Lindsborg, Kansas—“Little Sweden, U.S.A.”—the streets are lined with shops offering “An Adventure in Swedish Tradition,” and residents put on numerous festivals throughout the year highlighting Swedish folk customs. Such ethnic tourist towns have become increasingly widespread in the United States over the past thirty years. Tourists tend to perceive these places as towns where folk culture has been passed down unchanged for generations, while academics tend to dismiss residents' ethnicity as crass commercialism. Neither view is correct. Ethnicity and tradition are not static but constantly invented and reinvented. Modern folk ethnicity, among European Americans in particular, is simply the most recent incarnation of this process, one that attempts to recover ties to a specific, small‐scale landscape and history. This article explores the changing nature of the narratives of ethnicity and place‐based identity that the residents of Lindsborg have used to create a place for themselves in American society.

The Swedish Young Male Twins Register: a resource for studying risk factors for cardiovascular disease and insulin resistance.

A new Swedish twin register was created in 1998. All male twins born in Sweden 1973-1979 were identified in the Swedish Medical Birth Register. 3566 twins (1783 pairs) who were alive and residents of Sweden in 1997 were included in the new register. Data on birthweight, birthlength, gestational age, and so forth, were obtained from the Medical Birth Register. Record linkage was effected with the Military Service Conscription Register for the years 1991-1999. Anthropometrical data and information on blood pressure were obtained from this latter source. In 1998 a questionnaire was mailed to all twins in the register. Questions were posed about zygosity, socioeconomic conditions, lifestyle factors (physical activity, smoking habits, etc.), body shape and body size. Complete responses were obtained from 2654 twins (1327 pairs). In 2002 the cohort is being followed-up by a more extensive mailed questionnaire. Data will be collected about socioeconomic conditions, lifestyle, eating behaviour (TFEQ), body size and body shape. In the next few years genomic DNA will also be collected from buccal mucosa (using brush techniques).

Risk factors for invasive epithelial ovarian cancer: results from a Swedish case-control study.

This case-control study evaluated reproductive and other factors in relation to epithelial ovarian cancer (EOC) risk. Between 1993 and 1995, the authors recruited 655 EOC cases and 3,899 population controls aged 50-74 years who were born in and residents of Sweden. Data were collected through mailed questionnaires. Odds ratios were estimated by unconditional logistic regression. Parity reduced EOC risk (odds ratio = 0.61, 95% confidence interval (CI): 0.46, 0.81) for uniparous compared with nulliparous women. The risk of EOC decreased with incomplete pregnancies, early menopausal age, late age at first birth, and unilateral oophorectomy; increased with family history of ovarian cancer; and was not associated with menarcheal age, lactation, irregular menses, and menopausal symptoms. Histology-specific odds ratios of EOC for ever compared with never users of oral contraceptives were: serous, 0.56 (95% CI: 0.42, 0.74); mucinous, 1.96 (95% CI: 1.04, 3.68); endometrioid, 0.71 (95% CI: 0.49, 1.03); clear cell, 0.66 (95% CI: 0.31, 1.43); and all EOCs, 0.73 (95% CI: 0.59, 0.90). Prolonged oral contraceptive use reduced EOC risk, with persistent protection up to 25 years after the last use. Ever use of hormone replacement therapy increased EOC risk (odds ratio = 1.41, 95% CI: 1.15, 1.72). Among etiologic hypotheses, the retrograde transportation hypothesis accommodates most epidemiologic findings concerning EOC risk.

Suboptimal treatment of elderly nursing-home residents in Sweden

Suboptimal treatment of elderly nursing-home residents in Sweden