K. Sundquist

Neighbourhood deprivation and incidence of coronary heart disease: a multilevel study of 2.6 million women and men in Sweden

Study objective: To examine whether neighbourhood deprivation predicts incidence rates of coronary heart disease, beyond age and individual income. Design: Follow up study from 31 December 1995 to 31 December 1999. Women and men were analysed separately with respect to incidence rates of coronary heart disease. Multilevel logistic regression was used in the analysis with individual level characteristics (age, individual income) at the first level and level of neighbourhood deprivation at the second level. Neighbourhood deprivation was measured at small area market statistics level by the use of Care Need Index. Setting: Sweden. Participants: All women and men aged 40–64 in the Swedish population, in total 2.6 million people. Main results: There was a strong relation between level of neighbourhood deprivation and incidence rates of coronary heart disease for both women and men. In the full model, which took account of individual income, the risk of developing coronary heart disease was 87% higher for women and 42% higher for men in the most deprived neighbourhoods than in the most affluent neighbourhoods. For both women and men the variance at neighbourhood level was over twice the standard error, indicating significant differences in coronary heart disease risk between neighbourhoods. Conclusions: High levels of neighbourhood deprivation independently predict coronary heart disease for both women and men. Both individual and neighbourhood level approaches are important in health care policies.

Cancer risks in Crohn disease patients

BACKGROUNDnPatients diagnosed with Crohn disease (CD) are known to be at an increased risk of bowel cancers and lymphoma. CD is an autoimmune disease and we hypothesize that the patients are predisposed to a wider spectrum of cancers.nnnPATIENTS AND METHODSnA CD research database was constructed by identifying hospitalized CD patients from the Hospital Discharge Register and cancer patients from the Swedish Cancer Registry. Follow-up of 21 788 CD patients first hospitalized during the years 1964-2004 identified 1424 cancer cases. Standardized incidence ratios (SIRs) were calculated by comparing cancers in CD patients with subjects without CD.nnnRESULTSnIn addition to the known sites, many additional sites were in excess in CD patients. These included liver, pancreatic, lung, prostate, testicular, kidney and skin (squamous cell) cancers; nonthyroid endocrine tumors and leukemia. The previously established sites showed the highest SIRs; however, SIRs >2.0 were noted for the novel sites of the liver, testis and kidney. For testicular cancer, the SIR of seminoma was 2.74. Cancer risks were influences by age at first hospitalization for CD but whether the age effects were increasing or decreasing depending on the cancer type.nnnCONCLUSIONSnThis large study identified many novel subsequent cancers in CD patients.

Familial association between type 1 diabetes and other autoimmune and related diseases

Aims/hypothesisIn the era of genome-wide association studies, familial risks are used to estimate disease heritability and success in gene identification. We wanted to estimate associations between type 1 diabetes mellitus and 33 autoimmune and related diseases in parents, offspring, singleton siblings and twins.MethodsThe availability of a Multigeneration Register in Sweden provides reliable access to families throughout the last century. The diseases in individual family members were obtained through linkage to the Hospital Discharge Register. Standardised incidence ratios (SIRs) were calculated as relative risks of contracting type 1 diabetes in family members of affected patients compared with those lacking affected family members.ResultsAmong a total of 450,899 patients, 21,168 were diagnosed with type 1 diabetes. Familial cases amounted to 10.3% of all type 1 diabetes patients. SIR for type 1 diabetes was 8.23 in offspring of affected parents, 11.92 in singleton siblings, 39.22 in multiplex families and 21.88 in twins; the calculated risk for monozygotic twins was 32.33. Type 1 diabetes in offspring was associated with 13 diseases in parents, including Addison’s disease (SIR 2.41), asthma (1.38), coeliac disease (2.73), Graves’ disease/hyperthyroidism (1.86), Hashimoto disease/hypothyroidism (2.35), pernicious anaemia (3.09), primary biliary cirrhosis (3.63), rheumatoid arthritis (2.12), sarcoidosis (1.62), systemic lupus erythematosus (2.04), ulcerative colitis (1.23) and Wegener’s granulomatosis (2.12).Conclusions/interpretationThe concordant familial risks for type 1 diabetes were high and the calculated risk for multiplex families and monozygotic twins may be explained by epistatic geneu2009×u2009gene or geneu2009×u2009environment interactions. Familial associations with several autoimmune and related diseases suggest genetic sharing and challenge to gene identification.

Cancer risk in hospitalized rheumatoid arthritis patients

OBJECTIVESnPatients diagnosed with RA have been at an increased risk of many cancers and at a decreased risk of some cancers. We planned to revisit the theme by using a nation-wide population of RA patients.nnnMETHODSnAn RA research database was constructed by identifying hospitalized RA patients from the Hospital Discharge Register and cancer patients from the Cancer Registry. Earlier studies from Sweden have shown that some 75% of RA patients have been hospitalized at some time point. Follow-up of 42,262 RA patients was carried out from year 1980 to 2004 including separate follow-ups for shorter intervals. Standardized incidence ratios (SIRs) were calculated for cancer in RA patients by comparing with subjects without RA.nnnRESULTSnMany cancers were in excess in RA patients, especially Hodgkin disease, non-Hodgkin lymphoma and squamous cell skin cancer; a novel association was found for non-thyroid endocrine tumours. Colon, rectal and endometrial cancers were decreased in RA patients. When RA patients were first hospitalized after 1999, the SIRs for melanoma, squamous cell skin and upper aerodigestive tract cancers and for leukaemia were increased compared with previous periods.nnnCONCLUSIONSnThis study, the largest so far published, quantified the increased and decreased site-specific risks of cancer in RA patients. The recent increases in the risks of squamous cell skin and upper aerodigestive tract cancers, melanoma and leukaemia call for continuous vigilance and recording of changes in treatment.

Cancer risk among patients hospitalized for Type 1 diabetes mellitus: a population-based cohort study in Sweden

Diabet. Med. 27, 791–797 (2010)

Cancer risk in hospitalized sarcoidosis patients: a follow-up study in Sweden

BACKGROUNDnSarcoidosis patients show dysregulated immune function, which may be related to subsequent cancer. We examined here the overall and specific cancer risks among Swedish subjects who had been hospitalized for sarcoidosis.nnnMETHODSnA sarcoidosis research database was created by identifying hospitalized sarcoidosis patients from the Swedish Hospital Discharge Register and by linking them with the Cancer Registry. Standardized incidence ratios (SIRs) were calculated for cancers in sarcoidosis patients compared with subjects without sarcoidosis.nnnRESULTSnA total of 10 037 patients were hospitalized for sarcoidosis during years 1964-2004. Among them 1045 patients developed subsequent cancer, giving an overall SIR of 1.40 and 1.18 for cancer diagnosed later than 1 year of follow-up. A significant excess was noted for skin (squamous cell), kidney and nonthyroid endocrine tumors and additionally for non-Hodgkins lymphoma and leukemia. Patients with multiple hospitalizations showed high risks.nnnCONCLUSIONSnA 40% overall excess incidence of cancer was noted among sarcoidosis patients, but the increase was confined mainly to the first year after hospitalization. However, the increased risks of skin cancer and non-Hodgkins lymphoma and leukemia, especially for those with multiple hospitalizations or hospitalized at old age, call for clinical attention.

Care Need Index, a useful tool for the distribution of primary health care resources

Study objective: To demonstrate how Care Need Index (CNI), a social deprivation index, may be used to allocate total primary health care resources. Design: Cross sectional survey and register data. The CNI was based on sociodemographic factors: elderly persons living alone, children under age 5, unemployed people, people with low educational status, single parents, high mobility, and foreign born people. The CNI weights were calculated from the ratings of Swedish GPs of the impact of these factors on their workload. The CNI scale was transformed into a positive scale to avoid negative values. CNI weights were calculated for each decile of the study population. The risk of poor self reported health in the CNI deciles was estimated by means of a hierarchical logistic regression in the age range 25–74 (n=27 346). The MigMed database comprising all people living in Sweden was used to calculate the CNI for Stockholm. Participants: The Swedish population and the population in Stockholm County. Main results: The means of the CNI for deciles ranged from 61 (most affluent neighbourhoods) to 140 (most deprived) in Stockholm County. The ratio between the tenth and the first decile was 1.66. There was an approximately 150% increased risk of poor self reported health for people living in the most disadvantaged neighbourhoods (OR=2.50) compared with those living in the most affluent ones (OR=1). CNI ratios for the deciles corresponded approximately to the odds ratios of poor self reported health status. Conclusions: The CNI can be used to allocate total primary health care resources.

Cancer risk in hospitalised psoriasis patients: a follow-up study in Sweden

We examined overall and specific cancer risks among Swedish subjects who had been hospitalised one or more times for psoriasis. A database was created by identifying such patients from the Swedish Hospital Discharge Register and linking them with the Cancer Registry. Follow-up of patients was carried out from the last hospitalisation through 2004. A total of 15 858 patients were hospitalised for psoriasis during 1965–2004, of whom 1408 developed cancer, giving an overall standardised incidence ratios (SIRs) of 1.33. A significant excess was noted for squamous cell skin cancer, and for cancers of the upper aerodigestive tract, oesophagus, stomach, liver, pancreas, lung, kidney and bladder as well as non-Hodgkin lymphoma. Many of these may reflect the effects of alcohol drinking and tobacco smoking. Patients with multiple hospitalisations showed high risk, particularly for oesophageal (SIR 6.97) and skin (SIR 4.76) cancers.

Country of birth and body mass index: a national study of 2,000 immigrants in Sweden.

The aim of this study is to analyse the influence of country of birth on body mass index (BMI) after adjustment for age, educational status, physical activity and smoking habits. Two random samples of men and women, aged 27–60, were used: 1,957 immigrants and 2,975 Swedes, both from 1996. Men and women were analysed in separate models by the use of linear regression. The BMI levels were significantly higher among Polish (0.8 BMI units) and Chilean (0.7 BMI units) men, and Chilean (1.9␣BMI units) and Turkish (1.5 BMI units) women than among their Swedish controls, after adjustment for all explanatory variables. Other intermediate risk factors for cardiovascular disease, such as physical inactivity and daily smoking, were also more frequent among almost all the immigrant subgroups. This study shows a strong influence of country of birth on BMI even after adjustment for age, educational status, physical activity and smoking habits.

Familial risks for asthma among twins and other siblings based on hospitalizations in Sweden

Background Asthma is a common disabling condition, with known environmental and familial risk factors and with their assumed interactions. We wanted to carry out a family study on asthma to address gene–environment interactions at a population level.