Fracture risk in men with prostate cancer: a population-based study

Fractures are increased among men with prostate cancer, especially those on androgen-deprivation therapy (ADT), but few data are available on men with localized prostate cancer. The purpose of this investigation was to estimate fracture risk among unselected community men with prostate cancer and systematically assess associations with ADT and other risk factors for fracture. In a population-based retrospective cohort study, 742 Olmsted County, MN, men with prostate cancer first diagnosed in 1990-1999 (mean age 68.2 ± 8.9 years) were followed for 6821 person-years. We estimated cumulative fracture incidence, assessed relative risk by standardized incidence ratios, and evaluated risk factors in time-to-fracture regression models. All together, 482 fractures were observed in 258 men (71 per 1000 person-years). Overall fracture risk was elevated 1.9-fold, with an absolute increase in risk of 9%. Relative to rates among community men generally, fracture risk was increased even among men not on ADT but was elevated a further 1.7-fold among ADT-treated compared with untreated men with prostate cancer. The increased risk following various forms of ADT was accounted for mainly by associations with pathologic fractures (14% of all fractures). Among men not on ADT (62% of the cohort), more traditional osteoporosis risk factors were implicated. In both groups, underlying clinical characteristics prompting different treatments (indication bias) may have been partially responsible for the associations seen with specific therapies. To the extent that advanced-stage disease and pathologic fractures account for the excess risk, the effectiveness of fracture prevention among men with prostate cancer may be limited.

Survival of women with breast cancer in central and northern Denmark, 1998-2009

Objective

Breast cancer is the most common cancer among women worldwide. The Nordic countries have relatively high survival, but Denmark has a lower survival than neighboring countries. A breast cancer screening program was introduced in 2007 and 2008 in the northern and central regions of Denmark respectively. We aimed to examine possible changes in survival of Danish breast cancer patients in central and northern Denmark in the period 1998–2009.

Materials and methods

From the northern and central Denmark regions, we included all women (n = 13,756) with an incident diagnosis of breast cancer, as recorded in the Danish National Registry of Patients during the period January 1, 1998 through December 31, 2009. We calculated age-stratified survival and used Cox proportional hazard regression to estimate mortality rate ratios (MRRs) for all breast cancer patients.

Results

Median age was 62 years (21–102 years). The overall 1-year survival improved steadily over the period from 90.9% in 1998–2000 to 94.4% in 2007–2009, corresponding to a 1-year age adjusted MRR of 0.68 in 2007–2009 compared with the reference period 1998–2000. We estimated the 5-year survival to improve from 70.0% in 1998–2000 to 74.7% in 2007–2009, corresponding to a 5-year age adjusted MRR of 0.82 in 2007–2009 compared with the reference period 1998–2000. For middle-aged women (50–74 years) 1-year survival increased from 92.8% in 1998–2000 to 96.6% in 2008–2009, and 5-year survival was expected to increase from 73.9% in 1998–2000 to 80.2% in 2007–2009. Among younger women (15–49 years) and elderly women (>75 years), 1-year survival and 5-year predicted survival did not change over the two time periods.

Conclusion

Survival of breast cancer patients has improved in Denmark over the period 1998–2009, and this change was most distinct in women aged 50–74 years. Survival improved even before the implementation of a formal breast cancer screening program.

Similar cardiovascular risk factor profile in screen-detected and known type 2 diabetic subjects

OBJECTIVE. To compare the cardiovascular disease (CVD) risk factor profile in subjects with screen-detected type 2 diabetes (SDM) and subjects with known type 2 diabetes (KDM). DESIGN. Population-based, cross-sectional survey. SETTING AND SUBJECTS. In a single, semi-rural general practice 2082 subjects were between 20 and 69 years. Of those, 1970 subjects were invited, and a total of 1374 (69.7%) subjects were examined by blood tests, anthropometric measures, and self-administered questionnaires. RESULTS. Before the survey 19 persons were known to have type 2 diabetes. The screening revealed another 31 individuals with type 2 diabetes, diagnosed according to the 1999 World Health Organization criteria. Age, levels of blood pressure, BMI, and dyslipidaemia, and markers of haemostasis and inflammation were comparable in the two groups. Median age in the KDM group was 58 vs. 57 years in the SDM group, p = 0.82, 79% were male vs. 61%, p = 0.23. In both groups 74% had blood pressure ≥ 130/85 mmHg, p = 1.00. In both groups 90% had BMI ≥ 25, p = 1.00, and about half in both groups had BMI ≥ 30, p = 0.56. In the KDM group 63% had dyslipidaemia (low HDL cholesterol or elevated triglycerides) vs. 80% in the SDM group, p = 0.32. Median levels of plasminogen-activator-inhibitor (PAI-1), tissue plasminogen activator (t-PA), as well as fibrinogen and C-reactive protein (CRP) were without statistically significant differences in the two groups, p > 0.1. In contrast, in markers of glycaemic regulation statistically significant differences were found between groups. Median HbA1 was 8.0 vs. 6.5, p < 0.001. Median fasting whole blood glucose level was 8.8 mmol/L vs. 6.3 mmol/L, p < 0.001, and glucose at two hours during OGTT was 16.9 mmol/L vs. 11.2 mmol/L, p < 0.001. Median fasting serum insulin level was 52 pmol/L vs. 80 pmol/L, p = 0.039 and at two hours 127 pmol/L vs. 479 pmol/L, p < 0.001. CONCLUSIONS. The CVD risk-factor profile of SDM patients was similar to the expected adverse profile of patients with KDM. This indicates an already increased risk of cardiovascular disease in diabetic patients before the diabetes becomes clinically manifest, supporting the need for early diagnosis.

Influence of insulin-like growth factor binding protein (IGFBP)-1 and IGFBP-3 on bone health: results from the European Male Ageing Study

The aim of this study was to determine the influence of insulin-like growth factor binding protein (IGFBP)-1, IGFBP-3, and IGF-I on calcaneal ultrasound parameters in middle-aged and elderly European men. Men aged 40-79 years were recruited from population registers for participation in the European Male Ageing Study (EMAS). Subjects were invited by letter to complete a postal questionnaire and to attend for an interviewer-assisted questionnaire, quantitative ultrasound (QUS) of the calcaneus, and a fasting blood sample from which serum levels of IGFBP-1, IGFBP-3, IGF-I, estradiol (E(2)), and SHBG were assayed. The questionnaires included the Physical Activity Scale for the Elderly (PASE) and questions about smoking and alcohol consumption. Estimated bone mineral density (eBMD) was derived as a function of the QUS parameters speed of sound and broadband ultrasound attenuation. Height and weight were measured in all subjects. 3057 men, mean age 59.7 years (standard deviation 11.0) were included in the analysis. After adjusting for age, center, and BMI, higher levels of IGFBP-1 were associated with lower eBMD. Higher levels of both IGFBP-3 and IGF-I were associated with higher eBMD. After further adjustment for PASE score, current smoking, alcohol consumption, free E(2), and SHBG, IGFBP-3 and IGF-I, though not IGFBP-1, remained significantly associated with eBMD. IGFBP-1 was associated with bone health, though the effect could be explained by other factors. IGFBP-3 and IGF-I were independent determinants of bone health in middle-aged and elderly European men.

Incidence patterns for primary malignant spinal cord gliomas: a Surveillance, Epidemiology, and End Results study

OBJECT

Primary malignant spinal glioma represents a significant clinical challenge due to the devastating effect on clinical outcomes in the majority of cases. As they are infrequently encountered in any one center, there has been limited population-based data analysis on the incidence patterns of these aggressive tumors. The objective of this study was to use publically available Surveillance, Epidemiology and End Results (SEER) program data to examine the overall incidence and incidence patterns over time with regard to age at diagnosis, sex, race, primary site of tumor, and histological subtype in patients in whom primary malignant spinal cord gliomas were diagnosed between 1973 and 2006.

METHODS

The study population of interest was limited to primary, malignant, pathologically confirmed spinal cord gliomas based on data drawn from the SEER 9 standard registries for patients diagnosed between 1973 and 2006. Variables of interest included age at diagnosis, sex, race, primary site of tumor, and histological subtype of tumor. The SEER*Stat 6.5.2 program was used to calculate frequencies, age-adjusted incidence rates with 95% CIs, and annual percentage change (APC) statistics with a 2-sided p value. In addition, linear correlation coefficients (R(2)) were calculated for the time association stratified by variables of interest.

RESULTS

The overall age-adjusted incidence rate for primary malignant spinal gliomas was 0.12 per 100,000, which increased significantly over the study period (APC = 1.74; p = 0.0004; R(2) = 0.36). The incidence was highest in patients diagnosed at ages 35-49 (0.17 per 100,000), males (0.14 per 100,000), whites (0.13 per 100,000), and those with ependymomas (0.07 per 100,000). Over the study period, the incidence of ependymomas increased significantly (APC = 3.17; p < 0.0001; R(2) = 0.58) as did the incidence of these tumors in whites (APC = 2.13; p = 0.0001) and for both males (APC = 1.90, p value < 0.0001) and females (APC = 1.60, p < 0.0001). The authors found no significant changes in the incidence over time by age of diagnosis.

CONCLUSIONS

This study demonstrates an increasing overall incidence of primary, malignant spinal cord glioma over the past 3 decades. Notably, for ependymoma the incidence has increased, whereas the incidence of most other glioma subtypes remained stable. This may be due to improved diagnostic and surgical techniques, changes in histological classification criteria, and changes in neuropathology diagnostic criteria. Although primary, malignant spinal cord gliomas are rare, an improved understanding of the incidence will assist investigators and clinicians in planning potential studies and preparing for allocation of resources to care for these challenging patients.

The prevalence and determinants of antepartum mental health problems among women in the USA: a nationally representative population-based study

Mental health problems disproportionately affect women, particularly during childbearing years. We sought to estimate the prevalence of antepartum mental health problems and determine potential risk factors in a representative USA population. We examined data on 3,051 pregnant women from 11 panels of the 1996-2006 Medical Expenditure Panel Survey. Poor antepartum mental health was defined by self report of mental health conditions or symptoms or a mental health rating of "fair" or "poor." Multivariate regression analyses modeled the odds of poor antepartum mental health; 7.8% of women reported poor antepartum mental health. A history of mental health problems increased the odds of poor antepartum mental health by a factor of 8.45 (95% CI, 6.01-11.88). Multivariate analyses were stratified by history of mental health problems. Significant factors among both groups included never being married and self-reported fair/poor health status. This study identifies key risk factors associated with antepartum mental health problems in a nationally representative sample of pregnant women. Women with low social support, in poor health, or with a history of poor mental health are at an increased risk of having antepartum mental health problems. Understanding these risk factors is critical to improve the long-term health of women and their children.

Non-dioxin-like polychlorinated biphenyls and risk of endometriosis

BACKGROUND

Endometriosis, a gynecologic disorder affecting 8-10% of reproductive-age women in the United States, is defined as the presence of endometrial tissue outside the uterus and is linked to pelvic pain and infertility. Environmental contaminants, including polychlorinated biphenyls (PCBs), are hypothesized to contribute to endometriosis risk through effects on steroid hormones.

OBJECTIVE

We evaluated serum concentrations of certain noncoplanar PCBs, which have no or only weak dioxin-like properties, as risk factors for endometriosis.

METHODS

In a case-control study of Group Health enrollees in western Washington State, 20 PCB congeners were measured in serum from surgically confirmed endometriosis cases that were newly diagnosed between 1996 and 2001 (n = 251) and from female controls matched for age and reference year (n = 538).

RESULTS

Summed and estrogenic PCB concentrations were not associated with endometriosis risk [summed: odds ratio (OR) = 1.3; 95% confidence interval (CI), 0.8-2.2; estrogenic: OR = 1.1; 95% CI, 0.8-1.4]. Although several congener-specific ORs were statistically above or below the null (PCB 170: third quartile vs. lowest: OR = 0.5; 95% CI, 0.3-0.9; PCB 196: third quartile vs. lowest: OR = 0.4; 95% CI, 0.2-0.7; PCB 201: second vs. lowest: OR = 0.5; 95% CI, 0.3-0.8; third quartile vs. lowest: OR = 0.4; 95% CI, 0.2-0.7), there were no overall consistent patterns of endometriosis risk.

CONCLUSIONS

Taken in context with other North American studies, our findings suggest that noncoplanar PCB concentrations consistent within the range of exposure currently observed in western Washington State do not contribute meaningfully to endometriosis risk.

Existing data sources for clinical epidemiology: The North Denmark Bacteremia Research Database

Bacteremia is associated with high morbidity and mortality. Improving prevention and treatment requires better knowledge of the disease and its prognosis. However, in order to study the entire spectrum of bacteremia patients, we need valid sources of information, prospective data collection, and complete follow-up. In North Denmark Region, all patients diagnosed with bacteremia have been registered in a population-based database since 1981. The information has been recorded prospectively since 1992 and the main variables are: the patient’s unique civil registration number, date of sampling the first positive blood culture, date of admission, clinical department, date of notification of growth, place of acquisition, focus of infection, microbiological species, antibiogram, and empirical antimicrobial treatment. During the time from 1981 to 2008, information on 22,556 cases of bacteremia has been recorded. The civil registration number makes it possible to link the database to other medical databases and thereby build large cohorts with detailed longitudinal data that include hospital histories since 1977, comorbidity data, and complete follow-up of survival. The database is suited for epidemiological research and, presently, approximately 60 studies have been published. Other Danish departments of clinical microbiology have recently started to record the same information and a population base of 2.3 million will be available for future studies.

Vegetables, unsaturated fats, moderate alcohol intake, and mild cognitive impairment

BACKGROUND/AIMS

To investigate associations of the Mediterranean diet (MeDi) components and the MeDi score with mild cognitive impairment (MCI).

METHODS

Participants (aged 70-89 years) were clinically evaluated to assess MCI and dementia, and completed a 128-item food frequency questionnaire.

RESULTS

163 of 1,233 nondemented persons had MCI. The odds ratio of MCI was reduced for high vegetable intake [0.66 (95% CI = 0.44-0.99), p = 0.05] and for high mono- plus polyunsaturated fatty acid to saturated fatty acid ratio [0.52 (95% CI = 0.33-0.81), p = 0.007], adjusted for confounders. The risk of incident MCI or dementia was reduced in subjects with a high MeDi score [hazard ratio = 0.75 (95% CI = 0.46-1.21), p = 0.24].

CONCLUSION

Vegetables, unsaturated fats, and a high MeDi score may be beneficial to cognitive function.

Associations between short sleep duration and central obesity in women

STUDY OBJECTIVES

The aim was to assess associations between sleep duration, sleep stages, and central obesity in women.

DESIGN

Cross-sectional study.

SETTING

City of Uppsala, Sweden.

PARTICIPANTS

Population-based sample of 400 women (range 20-70 years).

INTERVENTIONS

Full-night polysomnography and measurement of anthropometric variables.

MEASUREMENTS AND RESULTS

Sleep duration was inversely related to both waist circumference and sagittal abdominal diameter. Sleep duration remained inversely related to waist circumference (adj. beta = -1.22 cm/h; P = 0.016) and sagittal abdominal diameter (adj. beta = -0.46 cm/h; P = 0.001) after adjusting for potential confounders. Duration of slow wave sleep (SWS, adj. beta = -0.058 cm/min; P = 0.025) and REM sleep (adj. beta = -0.062 cm/min; P = 0.002) were both inversely related to waist circumference afteradjustments. Moreover,duration of REM sleep was inversely related to sagittal abdominal diameter (adj. beta = -0.021 cm/min; P < 0.0001). These associations were stronger in young women (age < 50 years).

CONCLUSION

An inverse relationship between short sleep duration and central obesity was found in women after adjusting for confounders. Loss of SWS and REM sleep may be important factors in the association between sleep loss and central obesity.

Genes involved with folate uptake and distribution and their association with colorectal cancer risk

Folate status is an important predictor of colorectal cancer risk. Common genetic variants in genes involved in regulating cellular folate levels might also predict risk, but there are limited data on this issue. We conducted a family-based case-control association study of variants in four genes involved in folate uptake and distribution: FOLR1, FPGS, GGH and SLC19A1, using 1,750 population-based and 245 clinic-based cases of pathologically confirmed colorectal cancer and their unaffected relatives participating in the Colon Cancer Family Registries. Standardized questionnaires, administered to all participants, collected information on risk factors and diet. Standard molecular techniques were used to determine microsatellite instability (MSI) status on cases. tagSNPs (n = 29) were selected based on coverage as assessed by pairwise r2. We found no evidence that tagSNPs in these genes were associated with risk of colorectal cancer. For the SLC19A1-rs1051266 (G80A, Arg27His) missense polymorphism, the A/A genotype was not associated with risk of colorectal cancer using population-based (OR = 1.00; 95% CI = 0.81-1.23) or clinic-based (OR = 0.75; 95% CI = 0.44-1.29) families compared to the G/A and G/G genotypes. We found no evidence that the association between any tagSNP and CRC risk was modified by multivitamin use, folic acid use and dietary folate intake and total folate intake. The odds ratios were similar, irrespective of MSI status, tumor subsite and family history of colorectal cancer. In conclusion, we found no significant evidence that genetic variants in FOLR1, GGH, FPGS and SLC19A1 are associated with the risk of colorectal cancer.

Synergistic association between alcohol intake and body mass index with serum alanine and aspartate aminotransferase levels in older adults: the Rancho Bernardo Study

BACKGROUND

The association between body-mass-index (BMI), alcohol consumption and their joint effect in increasing the risk of elevated serum alanine (ALT) and aspartate (AST) is unclear in older community-dwelling adults.

AIM

To determine the association between alcohol, BMI, and their combined effect with serum ALT and AST in older community-dwelling adults in the United States.

METHODS

A cross-sectional, population-based study in participants (n = 2364) from the Rancho Bernardo Study (54% women; mean age: 70 years, BMI: 25 kg/m(2), alcohol users: 63%) who attended a research visit in 1984-87. BMI was recorded by a trained nurse and alcohol use ascertained by a validated questionnaire. Odds-ratio (OR) and 95% confidence intervals (CI) of elevated serum ALT and AST (defined as > or =30 U/L in men and > or =19 U/L in women) were calculated for alcohol and BMI separately and their joint exposure using logistic regression models.

RESULTS

In multivariate logistic regression models adjusted for age, alcohol use, total cholesterol, serum triglycerides, fasting plasma glucose, systolic blood pressure, and diabetes mellitus, obesity independently increased the odds of elevated ALT in this cohort of older men and women by 3.0 (95% CI, 1.7-5.3) and 1.8 (95% CI, 1.1-2.7) respectively. Joint effects of consuming >3 alcoholic drinks/day and obesity raised the odds of elevated ALT by 8.9 (95% CI, 2.4-33.1) and AST by 21-fold (95% CI, 2.6-170.1), demonstrating synergism. Obese participants had higher odds of elevated ALT even at 0 < or = 1 drink/day.

CONCLUSIONS

In older men and women, the combination of obesity with alcohol is synergistic in increasing the risk of liver injury.

The prevalence of disability in the oldest-old is high and continues to increase with age: findings from The 90+ Study

OBJECTIVES

To examine the prevalence and type of disability in the oldest-old (90+), the fastest growing age group in the United States.

METHODS

The current study included functional data on 697 participants from The 90+ Study, a population-based longitudinal study of aging and dementia in people aged 90 and older. Data were obtained by participant's informants via a written questionnaire. The prevalence of disability was calculated for two definitions using activities of daily living (ADLs). ADL difficulty was defined as difficulty with one or more ADLs whereas ADL dependency was defined as needing help on one or more ADLs.

RESULTS

ADL difficulty was present in 71% in 90-94 year olds, 89% in 95-99 year olds, and 97% in centenarians. ADL dependency was present in 44% of 90-94 year olds, 66% of 95-99 year olds, and 92% of centenarians. The ADL most commonly causing difficulty was walking (70%) whereas the ADL most commonly causing dependency was bathing (51%). Age, gender, and institutionalization were significantly associated with both ADL difficulty and ADL dependency.

CONCLUSIONS

Similar to studies in younger individuals, the current study suggests that the prevalence of disability continues to increase rapidly in people aged 90 and older. With the rapid growth in the number of people in this age group, disability in the oldest-old has major public health implications.

Long-term direct costs before and after proctocolectomy for ulcerative colitis: a population-based study in Olmsted County, Minnesota

PURPOSE

This study was designed to test the hypothesis that patients undergoing definitive surgery for chronic ulcerative colitis have reduced direct medical costs after, as compared with before, total proctocolectomy.

METHODS

A population-based cohort of patients who underwent proctocolectomy for ulcerative colitis from 1988 to 2007 was identified using the Rochester Epidemiology Project. Total direct healthcare costs were estimated from an administrative database. The primary outcome was the observed cost difference between the two-year period before surgery and the two-year period after a surgery/recovery period (surgery + 180 days). Statistical significance was assessed using paired t-tests and bootstrapping methods. Demographic data were presented as median (interquartile range) or frequency (proportion). Mean costs are reported in 2007 constant dollars.

RESULTS

Sixty patients were Olmsted County, Minnesota, residents at the time of surgery and for the entire period of observation. Overall 40 patients (66%) were men, median age was 42 (range, 31-52) years, and duration of median colitis was four (range, 1-11) years. Operations included ileal pouch-anal anastomosis (n = 45, mean cost of surgery/recovery period = $50,530) and total proctocolectomy with Brooke ileostomy (n = 15, mean cost of surgery/recovery period = $39,309). In the pouch subgroup, direct medical costs on average were reduced by $9,296 (P < 0.001, bootstrapped 95% confidence interval: $324-$15,628) during the two years after recovery. In the Brooke ileostomy subgroup, direct medical costs on average were reduced by $12,529 (P < 0.001, bootstrapped 95% confidence interval: $6,467-$18,688) in the two years after recovery.

CONCLUSION

Surgery for chronic ulcerative colitis resulted in reduced direct costs in the two years after surgical recovery. These observations suggest that surgical intervention for ulcerative colitis is associated with long-term economic benefit.

Factors associated with psychological distress in a community-dwelling Japanese population: the Ohsaki Cohort 2006 Study

BACKGROUND

In Asia, there has been no population-based epidemiological study using the K6, a 6-item instrument that assesses nonspecific psychological distress.

METHODS

Using cross-sectional data from 2006, we studied 43,716 (20,168 men and 23,548 women) community-dwelling people aged 40 years or older living in Japan. We examined the association between psychological distress and demographic, medical, lifestyle, and social factors by using the K6, with psychological distress defined as 13 or more points out of a total of 24 points.

RESULTS

The following variables were significantly associated with psychological distress among the population: female sex, young and old age, a history of serious disease (hypertension, diabetes mellitus, stroke, myocardial infarction, or cancer), current smoking, former alcohol drinking, low body mass index, shorter daily walking time, lack of social support (4 of 5 components), and lack of participation in community activities (4 of 5 components). Among men aged 40 to 64 years, only "lack of social support for consultation when in trouble" and a history of diabetes mellitus remained significant on multivariate analysis. Among men aged 65 years or older, age was not significantly associated with psychological distress, and the significant association with current smoking disappeared on multivariate analysis. Among women aged 40 to 64 years, a history of stroke was not associated with psychological distress. Among women aged 65 years or older, the significant association with current smoking disappeared on multivariate analysis.

CONCLUSIONS

A number of factors were significantly associated with psychological distress, as assessed by the K6. These factors differed between men and women, and also between middle-aged and elderly people.

Sibling risk of pediatric obstructive sleep apnea syndrome and adenotonsillar hypertrophy

OBJECTIVES

To estimate sibling risk of hospitalization for children with sleep disordered breathing (SDB), diagnosed with (1) obstructive sleep apnea syndrome (OSAS), or (2) adenotonsillar hypertrophy in the total Swedish population.

DESIGN, SETTING, AND PARTICIPANTS

Using the MigMed database at the Karolinska Institute, we divided the population of Sweden aged 0-18 years into sibling groups based on a shared mother and father and presence of a primary hospital diagnosis of OSAS or adenotonsillar hypertrophy for each individual born between 1978 and 1986, during the follow-up period 1997-2004. Individuals with at least one affected sibling were identified and the incidence rates were computed, using standardized incidence ratios (SIRs) with 95% confidence intervals (CIs). Reference groups were boys and girls with unaffected siblings of 2 or more.

RESULTS

After accounting for socioeconomic status, age, and geographic region, boys with at least one sibling with OSAS had an increased risk of having OSAS (SIR, 33.2; 95% CI, 16.5-64.8), and in girls the SIR was 40.5 (19.4-81.4). For hypertrophy of the tonsils or hypertrophy of the adenoids and tonsils the corresponding SIRs were 4.53 (3.0-6.8) for boys and 4.94 (3.3-7.4) for girls.

CONCLUSIONS

The study indicate an increased sibling risk of sleep disordered breathing in children, which may be due to heritable genes and/or shared environment such as increased awareness among family members or referring doctors. Caregivers should ask parents if siblings have similar symptoms, and thus offer them early treatment.

The University of Michigan Dioxin Exposure Study: methods for an environmental exposure study of polychlorinated dioxins, furans, and biphenyls

BACKGROUND

The University of Michigan Dioxin Exposure Study (UMDES) was undertaken in response to concerns that the discharge of dioxin-like compounds from the Dow Chemical Company facilities in Midland, Michigan, resulted in contamination of soils in the Tittabawassee River floodplain and areas of the city of Midland, leading to an increase in residents' body burdens of polychlorinated dibenzodioxins and polychlorinated dibenzofurans.

OBJECTIVES

The UMDES is a hypothesis-driven study designed to answer important questions about human exposure to dioxins in the environment of Midland, where the Dow Chemical Company has operated for > 100 years, and in neighboring Saginaw, Michigan. In addition, the UMDES includes a referent population from an area of Michigan in which there are no unusual sources of dioxin exposure and from which inferences regarding the general Michigan population can be derived. A central goal of the study is to determine which factors explain variation in serum dioxin levels and to quantify how much variation each factor explains.

CONCLUSIONS

In this article we describe the study design and methods for a large population-based study of dioxin contamination and its relationship to blood dioxin levels. The study collected questionnaire, blood, dust, and soil samples on 731 people. This study provides a foundation for understanding the exposure pathways by which dioxins in soils, sediments, fish and game, and homegrown produce lead to increased body burdens of these compounds.

Hospitalizations and deaths associated with Clostridium difficile infection, Finland, 1996-2004

To determine whether the rate of Clostridium difficile-associated disease (CDAD) and CDAD-related deaths were increasing in Finland, we analyzed registry data from 1996 through 2004. We determined the number of hospital discharges that had a diagnosis code specific for CDAD from the International Classification of Diseases, 10th revision: "enterocolitis due to Clostridium difficile" (A04.7) and "pseudomembranous enterocolitis associated with antimicrobial therapy" (K52.8), listed as any diagnosis in the National Hospital Discharge Registry. CDAD-related deaths were identified from death certificates. Those discharged with a CDAD diagnosis doubled from 810 (16/100,000 population) in 1996 to 1,787 (34/100,000) in 2004. The increase was most prominent for patients 7gt;64 years of age but concerned only those discharged with diagnosis code A04.7. The number of those discharged with diagnosis code K52.8 remained stable. The age-standardized mortality rate associated with CDAD increased from 9/million in 1998 to 17/million in 2004; the increase was limited to persons 7gt;64 years of age.

Familial risks of psychotic disorders and schizophrenia among siblings based on hospitalizations in Sweden

Familial risks of psychotic disorders and schizophrenia have been assessed in previous studies. However, the degree of familial clustering in large population datasets remains to be established. We conducted a study on familial risks of psychotic disorders and schizophrenia by linking the Multigeneration Register to the nationwide Swedish Hospital Discharge Register. All patients younger than 72 years hospitalized for psychotic disorders or schizophrenia between 1987 and 2004 were included. Standardized incidence ratios (SIRs) were calculated for individuals with affected singleton siblings, twins or spouses compared with individuals whose siblings or spouses had no hospitalization for psychotic disorders or schizophrenia. A total of 40,228 hospitalized cases were identified of which 3006 were affected sibling pairs. The overall significant familial SIRs were 4.82 for psychotic disorders and 7.34 for schizophrenia. The highest SIRs were found in the younger ages. There were no significant gender differences. The significant SIR for psychotic disorders among twin pairs was 6.40 and the significant SIRs for psychotic disorders among spouses varied between 3.17 and 3.29. Age difference between siblings had no effect on the magnitude of the SIRs. The findings of the present large-scale study suggest that heritable factors have a stronger effect on psychotic disorders and schizophrenia than environmental factors. Future studies could coordinate epidemiological studies of large populations with molecular biology resources.

The incidence of clinically diagnosed versus research-identified autism in Olmsted County, Minnesota, 1976-1997: results from a retrospective, population-based study

Autism prevalence studies have often relied on administrative prevalence or clinical diagnosis as case-identification strategies. We report the incidence of clinical diagnoses of autism spectrum disorders (ASD), versus research-identified autism among residents of Olmsted County, Minnesota, age < or =21 years, from 1976-1997. The incidence of clinically diagnosed ASD (with 95% CI) was 1.5 per 100,000 (0.0-3.7) in 1980-1983 and 33.1 (22.8-43.3) in 1995-1997, a 22.1-fold increase. In contrast, the incidence of research-identified autism increased from 5.5 (1.4-9.5) per 100,000 to 44.9 (32.9-56.9), an 8.2-fold increase. Only 46.8% of research-identified cases received a clinical diagnosis of ASD. These findings demonstrate the potential for misleading interpretation of results from epidemiologic studies that rely on clinical diagnosis of autism to identify cases.

Reliability of self-reported childhood physical abuse by adults and factors predictive of inconsistent reporting

Little is known about the reliability of self-reported child physical abuse (CPA) or CPA reporting practices. We estimated reliability and prevalence of self-reported CPA and identified factors predictive of inconsistent CPA reporting among 2,256 participants using surveys administered in 1995 and 2000. Reliability of CPA was fair to moderate (kappa = 0.41). Using a positive report from either survey, the prevalence of moderate (61.8%) and severe (12.0%) CPA was higher than at either survey alone. Compared to consistent reporters of having experienced CPA, inconsistent reporters were less likely to be > or = 30 years old (vs. 18-29) or Black (vs. White) and more likely to have < 12 years of education (vs. 12), have no alcohol-related problems (vs. having problems), or report one type (vs. > or = 2) of CPA. These findings may assist researchers conducting and interpreting studies of CPA.

Psychosocial risk markers for new onset irritable bowel syndrome--results of a large prospective population-based study

Irritable bowel syndrome (IBS) affects up to 22% of the general population. Its aetiology remains unclear. Previously reported cross-sectional associations with psychological distress and depression are not fully understood. We hypothesised that psychosocial factors, particularly those associated with somatisation, would act as risk markers for the onset of IBS. We conducted a community-based prospective study of subjects, aged 25-65 years, randomly selected from the registers of three primary care practices. Responses to a detailed questionnaire allowed subjects' IBS status to be classified using a modified version of the Rome II criteria. The questionnaire also included validated psychosocial instruments. Subjects free of IBS at baseline and eligible for follow-up 15 months later formed the cohort for this analysis (n=3732). An adjusted participation rate of 71% (n=2456) was achieved at follow-up. 3.5% (n=86) of subjects developed IBS. After adjustment for age, gender and baseline abdominal pain status, high levels of illness behaviour (odds ratio (OR)=5.2; 95% confidence interval (95% CI) 2.5-11.0), anxiety (OR=2.0; 95% CI 0.98-4.1), sleep problems (OR=1.6; 95% CI 0.8-3.2), and somatic symptoms (OR=1.6; 95% CI 0.8-2.9) were found to be independent predictors of IBS onset. This study has demonstrated that psychosocial factors indicative of the process of somatisation are independent risk markers for the development of IBS in a group of subjects previously free of IBS. Similar relationships are observed in other "functional" disorders, further supporting the hypothesis that they have similar aetiologies.

Sodium and potassium intake and risk of cardiovascular events and all-cause mortality: the Rotterdam Study

BACKGROUND

Dietary electrolytes influence blood pressure, but their effect on clinical outcomes remains to be established. We examined sodium and potassium intake in relation to cardiovascular disease (CVD) and mortality in an unselected older population.

METHODS

A case-cohort analysis was performed in the Rotterdam Study among subjects aged 55 years and over, who were followed for 5 years. Baseline urinary samples were analyzed for sodium and potassium in 795 subjects who died, 206 with an incident myocardial infarction and 181 subjects with an incident stroke, and in 1,448 randomly selected subjects. For potassium, dietary data were additionally obtained by food-frequency questionnaire for 78% of the cohort.

RESULTS

There was no consistent association of urinary sodium, potassium, or sodium/potassium ratio with CVD and all-cause mortality over the range of intakes observed in this population. Dietary potassium estimated by food frequency questionnaire, however, was associated with a lower risk of all-cause mortality in subjects initially free of CVD and hypertension (RR = 0.71 per standard deviation increase; 95% confidence interval: 0.51-1.00). We observed a significant positive association between urinary sodium/potassium ratio and all-cause mortality, but only in overweight subjects who were initially free of CVD and hypertension (RR = 1.19 (1.02-1.39) per unit).

CONCLUSION

The effect of sodium and potassium intake on CVD morbidity and mortality in Western societies remains to be established.

Office work exposures and adult-onset asthma

BACKGROUND

Office exposures have been linked to symptoms of sick building syndrome, but their relation to the development of asthma has not been studied previously. These exposures have increasing importance because an increasing proportion of the workforce is working in office environments.

OBJECTIVES

The aim of this study was to assess the relations of exposure to carbonless copy paper (CCP), paper dust, and fumes from photocopiers and printers to adult-onset asthma.

METHODS

We conducted a population-based incident case-control study of adults 21-63 years of age living in the Pirkanmaa District in South Finland. All new clinically diagnosed cases (n = 521) of asthma were recruited during a 3-year study period. A random sample of the source population formed the controls (n = 1,016). This part focused on 133 cases and 316 controls who were office workers according to their current occupation classified by the 1988 International Standard Classification of Occupations. All participants answered a questionnaire on health, smoking, occupation, and exposures at work and home. Subjects with previous asthma were excluded.

RESULTS

Exposures to paper dust [adjusted odds ratio (OR) = 1.97; 95% confidence interval (CI), 1.25-3.10] and CCP (OR = 1.66; 95% CI, 1.03-2.66) were related to significantly increased risk of adult-onset asthma. An exposure-response relation was observed between exposure to paper dust and risk of asthma.

CONCLUSIONS

This study provides new evidence that exposures to paper dust and CCP in office work are related to increased risk of adult-onset asthma. Reduction of these exposures could prevent asthma in office workers. Clinicians seeing asthma patients should be aware of this link to office exposures.

Ten years' experience with year-round active surveillance of up to 19 respiratory pathogens in children

INTRODUCTION

Surveillance systems for acute respiratory infections (ARI) in children currently are often limited in terms of the panel of pathogens and the age range investigated or are only syndromic and at times only active in the winter season.

METHODS

Within PID-ARI.net, a research network for ARI in children in Germany, an active, year-round surveillance system was formed in three regions from north to south for population-based analysis. Children from birth to 16 years of age were included and up to 19 noncolonizing airway pathogens were tested for with multiplex RT-PCR.

RESULTS

In the 10-year period from July 1996 to June 2006, a total of 18,899 samples were tested. The positive rate increased with the size of the test panel to up to 72.9%. Picornaviruses (35-39%), paramyxoviruses (23-28%) and orthomyxoviruses (5.8-12.5%) comprised the highest fraction. Reoviruses and Legionella pneumophila were not found at all and Chlamydia pneumoniae and Bordetella parapertussis only rarely. Respiratory syncytial virus and parainfluenza virus (PIV) type 3 were anticyclical in rhythmicity with metapneumovirus and PIV1 and PIV2. The age medians per pathogen depended predominantly upon the attack rate and interepidemic intervals.

CONCLUSION

Active surveillance systems for ARI are superior to passive systems. They should be pathogen-specific and comprehensive for viruses and bacteria and age ranges. They should be population-based and multilevel to avoid bias. The impact of atypical bacteria in children was highly overestimated in earlier studies.

Polymorphisms in the gene encoding sterol regulatory element-binding factor-1c are associated with type 2 diabetes

AIMS/HYPOTHESIS

The sterol regulatory element-binding factor (SREBF)-1c is a transcription factor involved in the regulation of lipid and glucose metabolism. We have previously found evidence that a common SREBF1c single-nucleotide polymorphism (SNP), located between exons 18c and 19c, is associated with an increased risk of type 2 diabetes. The present study aimed to replicate our previously reported association in a larger case-control study and to examine an additional five SREBF1c SNPs for their association with diabetes risk and plasma glucose concentrations.

METHODS

We genotyped six SREBF1c SNPs in two case-control studies (n=1,938) and in a large cohort study (n=1,721) and tested for association with type 2 diabetes and with plasma glucose concentrations (fasting and 120-min post-glucose load), respectively.

RESULTS

In the case-control studies, carriers of the minor allele of the previously reported SNP (rs11868035) had a significantly increased diabetes risk (odds ratio [OR]=1.20 [95% CI 1.04-1.38], p=0.015). Also, three other SNPs (rs2236513, rs6502618 and rs1889018), located in the 5' region, were significantly associated with diabetes risk (OR > or =1.21, p< or =0.006). Furthermore, two SNPs (rs2236513 and rs1889018) in the 5' region were weakly (p<0.09) associated with plasma glucose concentrations in the cohort study. Rare homozygotes had increased (p< or =0.05) 120-min post-load glucose concentrations compared with carriers of the wild-type allele. Haplotype analyses showed significant (p=0.04) association with diabetes risk and confirmed the single SNP analyses.

CONCLUSIONS/INTERPRETATION

In summary, we replicated our previous finding and found evidence for SNPs in the 5' region of the SREBF1c gene to be associated with the risk of type 2 diabetes and plasma glucose concentration.

Pain, depression, and fatigue in community-dwelling adults with and without a history of cancer

The State of the Science Report by the National Cancer Institute on Symptom Management in Cancer identified gaps in understanding the epidemiology of pain, depression, and fatigue, and called for studies that will identify the extent of risk for these symptoms among those with cancer relative to other populations. Using year 2000 data from the Health and Retirement Study, a survey of a nationally representative sample of adults aged > or =50, we evaluated whether respondents with a history of cancer had excess risk for pain, depression, and fatigue compared to those without a history of cancer. We also compared clustering/co-occurrence of symptoms. Controlling for the confounding effects of comorbidities, sociodemographic, and access to care factors, respondents with a history of cancer had higher risk for fatigue (OR = 1.45; 95%CI = 1.29,1.63), depression (OR = 1.21; 95%CI = 1.06,1.37), and pain (OR = 1.15; 95%CI = 1.03,1.28). Symptom clusters were also more prevalent among those with a history of cancer (P < 0.001), with the pain-depression-fatigue cluster as most prevalent.

Tubular and glomerular kidney effects in Swedish women with low environmental cadmium exposure

Cadmium is a well-known nephrotoxic agent in food and tobacco, but the exposure level that is critical for kidney effects in the general population is not defined. Within a population-based women's health survey in southern Sweden (Women's Health in the Lund Area, WHILA), we investigated cadmium exposure in relation to tubular and glomerular function, from 1999 through early 2000 in 820 women (71% participation rate) 53-64 years of age. Multiple linear regression showed cadmium in blood (median, 0.38 microg/L) and urine (0.52 microg/L; density adjusted = 0.67 microg/g creatinine) to be significantly associated with effects on renal tubules (as indicated by increased levels of human complex-forming protein and N-acetyl-beta-D-glucosaminidase in urine), after adjusting for age, body mass index, blood lead, diabetes, hypertension, and regular use of nephrotoxic drugs. The associations remained significant even at the low exposure in women who had never smoked. We also found associations with markers of glomerular effects: glomerular filtration rate and creatinine clearance. Significant effects were seen already at a mean urinary cadmium level of 0.6 microg/L (0.8 microg/g creatinine). Cadmium potentiated diabetes-induced effects on kidney. In conclusion, tubular renal effects occurred at lower cadmium levels than previously demonstrated, and more important, glomerular effects were also observed. Although the effects were small, they may represent early signs of adverse effects, affecting large segments of the population. Subjects with diabetes seem to be at increased risk.

Population-based epidemiology of intensive care: critical importance of ascertainment of residency status

INTRODUCTION

Few studies evaluating the epidemiology of critical illness have used strict population-based designs that exclude subjects external to the base population. The objective of this study was to evaluate the potential effects of inclusion of nonresidents in population-based studies in intensive care.

METHODS

A population-based cohort study including all adults admitted to Calgary Health Region (CHR) multidisciplinary and cardiovascular surgical intensive care units (ICUs) between 1 May 1999 and 30 April 2003 was conducted. A comparison of patients resident and nonresident in the base population was then performed.

RESULTS

A total of 12,193 adult patients had at least one admission to an ICU; 7767 (63.7%) were CHR residents, for an incidence of 263.7 per 100,000 per year. Male CHR residents were at significant increased risk for ICU admission as compared with females (330.5 per 100,000 versus 198.2 per 100,000; relative risk, 1.67; 95% confidence interval, 1.59-1.74; P < 0.0001), as were CHR residents aged 65 years and older as compared with younger patients (1719.9 per 100,000 versus 238.7 per 100,000; relative risk, 7.21; 95% confidence interval, 6.95-7.47; P < 0.0001). The mortality rate was significantly lower among non-CHR residents (12.7%) as compared with CHR residents (20.0%; P < 0.0001). Logistic regression modeling identified CHR residency as an independent risk factor for death (odds ratio, 1.4; 95% confidence interval, 1.2-1.5; P < 0.0001).

CONCLUSION

This study provides information on the incidence of and demographic risk factors for admission to ICUs in a defined population. Inclusion of patients that are nonresident in base study populations may lead to gross errors in determination of the occurrence and outcomes of critical illness.

Continuity of care and patient outcomes after hospital discharge

BACKGROUND

Patients are often treated in hospital by physicians other than their regular community doctor. After they are discharged, their care is often returned to their regular community doctor and patients may not see the hospital physician. Transfer of information between physicians can be poor. We determined whether early postdischarge outcomes changed when patients were seen after discharge by physicians who treated them in the hospital.

METHODS

This cohort study used population-based administrative databases to follow 938833 adults from Ontario, Canada, after they were discharged alive from a nonelective medical or surgical hospitalization between April 1, 1995, and March 1, 2000. We determined when patients were seen after discharge by physicians who treated them in the hospital, physicians who treated them 3 months prior to admission (community physicians), and specialists. The outcome of interest was 30-day death or nonelective readmission to hospital.

RESULTS

Of patients studied, 7.7% died or were readmitted. The adjusted relative risk of death or readmission decreased by 5% (95% confidence interval [CI], 4% to 5%) and 3% (95% CI, 2% to 3%) with each additional visit to a hospital physician rather than a community physician or specialist, respectively. The effect of hospital physician visits was cumulative, with the adjusted risk of 30-day death or nonelective readmission reduced to 7.3%, 7.0%, and 6.7% if patients had 1, 2, or 3 visits, respectively, with a hospital rather than a community physician. The effect was consistent across important subgroups.

CONCLUSIONS

Patient outcomes could be improved if their early postdischarge visits were with physicians who treated them in hospital rather than with other physicians. Follow-up visits with a hospital physician, rather than another physician, could be a modifiable factor to improve patient outcomes following discharge from hospital.

Increase of chemotherapy use in older women with breast carcinoma from 1991 to 1996

BACKGROUND

There is little population-based information available on the actual use of chemotherapy and how closely this use mirrors consensus recommendations. The authors hypothesized that given the relative stability of consensus conference recommendations on chemotherapy use during the period 1991-1996 the patterns of use would more closely approximate consensus recommendation over time.

METHODS

The authors studied women who received a diagnosis of Stage I-IV (American Joint Committee on Cancer staging) breast carcinoma at age 65 years and older from 1991 through 1996, using the SEER cancer registry cases linked with Medicare claims.

RESULTS

Overall, women whose disease was diagnosed in 1996 had a 30% higher chance of receiving chemotherapy than those in 1991, after controlling for changes in tumor size, stage, and other factors. The use of chemotherapy was strongly influenced by age, with women age 65-69 years more than twice as likely to receive it as were women 70 years and older. The increase over time in chemotherapy depended on both tumor stage and patient age. For Stage I tumor, there was no increase in chemotherapy for any age. For Stage II, the increase was limited to younger women, whereas for Stage III and IV it was observed in women age 70 years and older.

CONCLUSIONS

There was a significant increase of chemotherapy use over time from 1991 to 1996 in women age 65 years and older with breast carcinoma. The increase was limited to younger women and those with advanced stage at diagnosis. Thus, consensus recommendations and community practice seemed to mirror each other over time.

First results from an intensified monitoring system to estimate drug related hospital admissions

AIMS

An intensified monitoring system was set up to identify drug related hospital admissions and estimate population-based incidences for commonly prescribed medications.

METHODS

Pharmacovigilance-centres systematically screened nonelective admissions to emergency rooms or departments of internal medicine for drug related hospitalizations (DRH). Clinical pharmacologists used standardized causality assessment. Service areas of each acute care hospital were defined by 5 digit postal codes that covered 60% of all admissions. Drug dispensing information was available through claims processed by regional pharmacy computing centres. Quarterly incidences were estimated by dividing the number of events by the number of treated patients.

RESULTS

435 DRHs were reported during five quarters. The incidence of ADRs leading to admissions varied for specific drug groups from 1.5/10 000 treated patients to 24/10 000. Quarterly variation of incidences was moderate except for insulin and calcium antagonists. 95% confidence intervals overlap for all quarters within each group. Incidences are sensitive to changes in the definition of the source population.

CONCLUSIONS

Our pharmacovigilance monitoring system allows comparisons of population-based incidences of drug-related hospitalizations among drugs and over time. It provides important information for risk management and monitoring outcomes of pharmaceutical quality management programmes.

Preterm delivery and risk of breast cancer

To explore the risk of breast cancer in relation to the length of a pregnancy we tested whether a preterm delivery carries a higher risk of breast cancer than does a full-term delivery. Based on information from the Civil Registration System, and the National Birth Registry in Denmark, we established a population-based cohort of 474 156 women born since April 1935, with vital status and detailed parity information, including the gestational age of liveborn children and stillbirths. Information on spontaneous and induced abortions was obtained from the National Hospital Discharge Registry and the National Registry of Induced Abortions. Incident cases of breast cancer in the cohort (n = 1363) were identified through linkage with the Danish Cancer Registry. The period at risk started in 1978 and continued until a breast cancer diagnosis, death, emigration, or 31 December, 1992, whichever occurred first. After adjusting for attained age, parity, age at first birth and calendar period, we observed the following relative risks of breast cancer for different lengths of the pregnancy: < 29 gestational weeks = 2.11 (95% confidence interval 1.00-4.45); 29-31 weeks = 2.08 (1.20-3.60); 32-33 weeks = 1.12 (0.62-2.04); 34-35 weeks = 1.08 (0.71-1.66); 36-37 weeks = 1.04 (0.83-1.32); 38-39 weeks = 1.02 (0.89-1.17); 40 weeks = 1 (reference). Parous women who had a preterm delivery below 32 weeks gestation had a 1.72-fold (1.14-2.59) increased risk of breast cancer compared with other parous women. In conclusion, a preterm delivery of 32+ weeks gestation did not significantly increase a woman's risk of contracting breast cancer. Only for the very small group of women with preterm deliveries of less than 32 weeks gestation did we observe an increased risk.

Poly(8-aminoguanylic acid): formation of ordered self-structures and interaction with poly(cytidylic acid)

Poly(8-aminoguanylic acid) has in neutral solution a novel ordered structure of high stability. The 8-amino group permits formation of three hydrogen bonds between two residues along the "top", or long axis, of the purines. The usual hydrogen bonding protons and Watson-Crick pairing sites are not involved in the association. The bonding scheme has a twofold rotation axis and is hemiprotonated at N(7). Poly(8NH2G) is converted by alkaline titration (pK = 9.7) to a quite different ordered structure, which is the favored form over the range approximately pH 10-11. The bonding scheme appears to be composed of a planar, tetrameric array of guanine residues, in which the 8-amino group does not participate in interbase hydrogen bonding. Poly (8NH2G) does not interact with poly(C) in neutral solution because of the high stability of the hemiprotonated G-G self-structure. Titration to the alkaline plateau, however, permits ready formation of a two-stranded Watson-Crick helix. In contrast to the monomer 8NH2GMP, poly(8NH2G) does not form a triple helix with poly(C) under any conditions. The properties of the ordered structures are interpreted in terms of a strong tendency of the 8-amino group to form a third interbase hydrogen bond, when this possibility is not prevented by high pH.