BACKGROUND: Self-selection may compromise cost-effectiveness of screening programs. We hypothesized that nonparticipants have generally higher morbidity and mortality than participants. METHODS: A Swedish population-based random sample of 1,986 subjects ages 59 to 61 years was invited to sigmoidoscopy screening and followed up for 9 years by means of multiple record linkages to health and population registers. Gender-adjusted cancer incidence rate ratio (IRR) and overall and disease group-specific and mortality rate ratio (MRR) with 95% confidence intervals (95% CI) were estimated for nonparticipants relative to participants. Cancer and mortality rates were also estimated relative to the age-matched, gender-matched, and calendar period-matched Swedish population using standardized incidence ratios and standardized mortality ratios. RESULTS: Thirty-nine percent participated. The incidence of colorectal cancer (IRR, 2.2; 95% CI, 0.8-5.9), other gastrointestinal cancer (IRR, 2.7; 95% CI, 0.6-12.8), lung cancer (IRR, 2.2; 95% CI, 0.8-5.9), and smoking-related cancer overall (IRR, 1.4; 95% CI, 0.7-2.5) tended to be increased among nonparticipants relative to participants. Standardized incidence ratios for most of the studied cancers tended to be >1.0 among nonparticipants and
Both influenza and meningococcal disease (MD) show seasonal variation with peak incidence rates during the winter. We examined whether fluctuations in occurrence of influenza were associated with changes in the incidence rate of MD, either simultaneously or with a delay of one or 2 weeks, and whether age had an impact on these associations. This ecological study was based on weekly surveillance data on influenza and a complete registration of MD cases (n = 413) in North Jutland County, Denmark, during 1980-1999. A total of 379 MD cases occurred during weeks with influenza registration. The analysis was done using a Poisson regression model taking into account the seasonal variation and trend over time in incidence rate of MD, and stratified by age: or = 14 years (n = 152). An increase of 100 registered cases of influenza per 100,000 inhabitants was associated with a 7% (95% CI: -1 to 15%) increase in the number of MD cases during the same week. The association was most marked for
Recent research advocates the use of count models with random parameters as an alternative method for analyzing accident frequencies. In this paper a dataset composed of urban arterials in Vancouver, British Columbia, is considered where the 392 segments were clustered into 58 corridors. The main objective is to assess the corridor effects with alternate specifications. The proposed models were estimated in a Full Bayes context via Markov Chain Monte Carlo (MCMC) simulation and were compared in terms of their goodness of fit and inference. A variety of covariates were found to significantly influence accident frequencies. However, these covariates resulted in random parameters and thereby their effects on accident frequency were found to vary significantly across corridors. Further, a Poisson-lognormal (PLN) model with random parameters for each corridor provided the best fit. Apart from the improvement in goodness of fit, such an approach is useful in gaining new insights into how accident frequencies are influenced by the covariates, and in accounting for heterogeneity due to unobserved road geometrics, traffic characteristics, environmental factors and driver behavior. The inclusion of corridor effects in the mean function could also explain enough variation that some of the model covariates would be rendered non-significant and thereby affecting model inference.
The aims of this study were to determine the magnitude of the increase in fracture risk after hospitalization for stroke, and in particular to determine the time course of this risk.
The records of the Swedish register of patients admitted during 1987-1996 were examined to identify all patients who were admitted to the hospital for stroke. Patients were followed for subsequent hospitalizations for hip and all fractures combined. We analyzed 16.3 million hospitalizations, from which 273 288 individuals with stroke were identified. A Poisson model was used to determine the absolute risk of subsequent fractures and the risk compared with that of the general population.
After hospitalization for stroke, there was a >7-fold increase in fracture risk, including that for hip fracture within the first year after hospitalization for stroke. Thereafter, fracture risk declined toward, but did not attain, the baseline risk except in men and women aged >/=80 years.
The high incidence of new fractures within the first year of hospitalization for stroke suggests that such patients should be preferentially targeted for treatment. It is possible that short courses of treatment at the time of stroke would provide important therapeutic dividends.
The aims of this study were to determine the magnitude of the increase in risk of further fracture following hospitalization for vertebral fracture, and in particular to determine the time course of this risk. The records of the Swedish Patient Register were examined from 1987 to 1994 to identify all patients who were admitted to hospital for thoracic or lumbar vertebral fractures. Vertebral fractures were characterized as due to high- or low-energy trauma. Patients were followed for subsequent hospitalizations for hip fracture, and for all fractures combined. A Poisson model was used to determine the absolute risk of subsequent nonvertebral fracture and compared with that of the general population. We analyzed 13.4 million hospital admissions from which 28,869 individuals with vertebral fracture were identified, of which 60% were associated with low-energy trauma. There was a marked increase in subsequent incidence of hip and all fractures within the first year following hospitalization for vertebral fracture in both men and women. Thereafter, fracture incidence declined toward, but did not attain, baseline risk. Increased risks were particularly marked in the young. The increase in fracture risk was more marked following low-energy vertebral fracture than in the case of high-energy trauma. We conclude that the high incidence of new fractures within a year of hospitalization for vertebral fractures, irrespective of the degree of trauma involved, indicates that such patients should be preferentially targeted for treatment. It is speculated that short courses of treatment at the time of first vertebral fracture could provide important therapeutic dividends.
Nursing home residents are prone to acute illness due to their high age, underlying illnesses and immobility. We examined the incidence of acute hospital admissions among nursing home residents versus the age-matched community dwelling population in a geographically defined area during a two years period. The hospital stays of the nursing home population are described according to diagnosis, length of stay and mortality. Similar studies have previously not been reported in Scandinavia.
The acute hospitalisations of the nursing home residents were identified through ambulance records. These were linked to hospital patient records for inclusion of demographics, diagnosis at discharge, length of stay and mortality. Incidence of hospitalisation was calculated based on patient-time at risk.
The annual hospital admission incidence was 0.62 admissions per person-year among the nursing home residents and 0.26 among the community dwellers. In the nursing home population we found that dominant diagnoses were respiratory diseases, falls-related and circulatory diseases, accounting for 55% of the cases. The median length of stay was 3 days (interquartile range = 4). The in-hospital mortality rate was 16% and 30 day mortality after discharge 30%.
Acute hospital admission rate among nursing home residents was high in this Scandinavian setting. The pattern of diagnoses causing the admissions appears to be consistent with previous research. The in-hospital and 30 day mortality rates are high.
Public Health Agency of Canada, Centre for Food-Borne, Environmental and Zoonotic Infectious Diseases, Environmental Issues Division, Canada; Faculty of Medicine, Department of Community Health and Epidemiology, Queen's University, Canada. Electronic address: email@example.com.
The purpose of this study was to assess the effects of extreme ambient temperature on hospital emergency room visits (ER) related to mental and behavioral illnesses in Toronto, Canada.
A time series study was conducted using health and climatic data from 2002 to 2010 in Toronto, Canada. Relative risks (RRs) for increases in emergency room (ER) visits were estimated for specific mental and behavioral diseases (MBD) after exposure to hot and cold temperatures while using the 50th percentile of the daily mean temperature as reference. Poisson regression models using a distributed lag non-linear model (DLNM) were used. We adjusted for the effects of seasonality, humidity, day-of-the-week and outdoor air pollutants.
We found a strong association between MBD ER visits and mean daily temperature at 28?C. The association was strongest within a period of 0-4 days for exposure to hot temperatures. A 29% (RR=1.29, 95% CI 1.09-1.53) increase in MBD ER vists was observed over a cumulative period of 7 days after exposure to high ambient temperature (99th percentile vs. 50th percentile). Similar associations were reported for schizophrenia, mood, and neurotic disorers. No significant associations with cold temperatures were reported.
The ecological nature and the fact that only one city was investigated.
Our findings suggest that extreme temperature poses a risk to the health and wellbeing for individuals with mental and behavior illnesses. Patient management and education may need to be improved as extreme temperatures may become more prevalent with climate change.
Treatments for Hodgkin lymphoma are associated with large relative risks of acute myeloid leukemia (AML), but there are few estimates of the excess absolute risk (EAR), a useful measure of disease burden. One-year Hodgkin lymphoma survivors (N = 35,511) were identified within 14 population-based cancer registries in Nordic countries and North America from January 1, 1970, through December 31, 2001. We used Poisson regression analysis to model the EAR of AML, per 10,000 person-years. A total of 217 Hodgkin lymphoma survivors were diagnosed with AML (10.8 expected; unadjusted EAR = 6.2; 95% confidence interval = 5.4 to 7.1). Excess absolute risk for AML was highest during the first 10 years after Hodgkin lymphoma diagnosis but remained elevated thereafter. In subsequent analyses, adjusted for time since Hodgkin lymphoma diagnosis and presented for the 5-9 year interval, the EAR was statistically significantly (P or = 35 age groups, respectively), which may be associated with modifications in chemotherapy.
This study investigated crisis intervention in three secondary schools after the suicides of five students, focusing on the relation between crisis intervention and suicide contagion. The contagion hypothesis was supported. Following a suicide, the number of suicides that occurred in secondary schools in one year were markedly increased beyond chance. No new suicides took place at schools where adequate first talk-throughs and psychological debriefing were conducted by a mental health professional. Proper crisis intervention is recommended to prevent suicide contagion in schools.