Unknown Risk Factors (unknown + risk_factor)

Distribution by Scientific Domains

Selected Abstracts

Testicular cancer: Marked birth cohort effects on incidence and a decline in mortality in southern Netherlands since 1970

Rob Verhoeven
Abstract The aim of our study was to interpret the changing incidence, and to describe the mortality of patients with testicular cancer in the south of the Netherlands between 1970 and 2004. On the basis of data from the Eindhoven Cancer Registry and Statistics Netherlands, 5-year moving average standardised incidence and mortality rates were calculated. An age-period-cohort (APC) Poisson regression analysis was performed to disentangle time and birth cohort effects on incidence. The incidence rate remained stable for all ages at about 3 per 100,000 person-years until 1989 but increased annually thereafter by 4% to 6 in 2004. This increase can almost completely be attributed to an increase in localised tumours. The largest increase was found for seminoma testicular cancer (TC) patients aged 35,39 and non-seminoma TC patients aged 20,24 years. Relatively more localised and tumours with lymph node metastases were detected in the later periods. APC analysis showed the best fit with an age-cohort model. An increase in incidence of TC was found for birth cohorts since 1950. The mortality rate dropped from 1.0 per 100,000 person-years in 1970 to 0.3 in 2005, with a steep annual decline of 12% in the period 1979,1986. In conclusion, the increase in incidence of TC was strongly correlated with birth cohorts since 1945. The increase in incidence is possibly caused by in utero or early life exposure to a yet unknown risk factor. There was a steep decline in mortality in the period 1979,1986. © 2007 Wiley-Liss, Inc. [source]

Pulmonary pathology in patients with AIDS: an autopsy study from Mumbai

HIV MEDICINE, Issue 4 2001
DN Lanjewar
Objective Although India has a high prevalence of HIV/AIDS, the associated pathologies responsible for morbidity have not been evaluated previously in a representative study. Hence, an autopsy study was carried out to analyse the spectrum of pulmonary lesions in patients with HIV/AIDS. Methods A retrospective and prospective autopsy study was carried out during 1988,2000 at Mumbai, India. Lungs from 143 adults, with at least 10 sections from each case, were examined using routine and special stains. Results The risk factors for 97 men (68%) and 38 women (27%) included: heterosexual sex with multiple partners (135 cases, 95%); blood transfusions (three cases; 2%); sex between men (two cases; 1%); and unknown risk factors (three cases, 2%). Pulmonary pathology was observed in 126 (88%) cases. The lesions identified were tuberculosis (85 cases, 59%), bacterial pneumonia (26 cases, 18%), cytomegalovirus (CMV) infection (10 cases, 7%), cryptococcosis (eight cases, 6%), Pneumocystis carinii pneumonia (seven cases, 5%), aspergillosis (four cases, 3%), toxoplasmosis (two cases, 1%), Kaposi's sarcoma (one case, 1%), squamous cell carcinoma (one case, 1%). Two or more infections were observed in 18 (13%) cases. Conclusions Pulmonary diseases and risk factors among patients with AIDS in India differ from those reported in industrialized countries. Tuberculosis was the most frequently observed pulmonary infection, followed by bacterial pneumonia and CMV pneumonitis. In contrast with industrialized countries, PCP remains less common in our patients. The information on opportunistic infections obtained in this study will be useful for managing HIV/AIDS cases at district level hospitals where diagnosing specific HIV-associated diseases is not always possible. [source]

ORIGINAL ARTICLE: Venous thromboembolism and subsequent diagnosis of subarachnoid hemorrhage: a 20-year cohort study

Summary.,Background:,Venous thromboembolism is a predictor of subsequent risk of ischemic stroke and intracerebral hemorrhage, but no data are available regarding its association with risk of subarachnoid hemorrhage. Objectives:,To examine this issue, we conducted a nationwide cohort study in Denmark. Patients and methods: Between 1977 and 2007, we identified 97 558 patients with a hospital diagnosis of venous thromboembolism and obtained information on risk of subsequent subarachnoid hemorrhage during follow-up in the Danish Registry of Patients. The incidence of subarachnoid hemorrhage in the venous thromboembolism cohort was compared with that of 453 406 population control cohort members. Results:,For patients with pulmonary embolism (PE), there was clearly an increased risk of subarachnoid hemorrhage, both during the first year of follow-up [relative risk 2.69; 95% confidence interval (CI), 1.32,5.48] and during later follow-up of 2,20 years (relative risk 1.40; 95% CI, 1.05,1.87). For patients with deep venous thrombosis (DVT) the risk was likewise clearly increased during the first year of follow-up (relative risk 1.91; 95% CI, 1.13,3.22), but not during later follow-up (relative risk 1.04; 95% CI, 0.81,1.32). Conclusions:,We found evidence that PE is associated with an increased long-term risk of subarachnoid hemorrhage. The two diseases might share etiologic pathways affecting the vessel wall or share unknown risk factors. [source]

Bayesian Detection of Clusters and Discontinuities in Disease Maps

BIOMETRICS, Issue 1 2000
Leonhard Knorr-Held
Summary. An interesting epidemiological problem is the analysis of geographical variation in rates of disease incidence or mortality. One goal of such an analysis is to detect clusters of elevated (or lowered) risk in order to identify unknown risk factors regarding the disease. We propose a nonparametric Bayesian approach for the detection of such clusters based on Green's (1995, Biometrika82, 711,732) reversible jump MCMC methodology. The prior model assumes that geographical regions can be combined in clusters with constant relative risk within a cluster. The number of clusters, the location of the clusters, and the risk within each cluster is unknown. This specification can be seen as a change-point problem of variable dimension in irregular, discrete space. We illustrate our method through an analysis of oral cavity cancer mortality rates in Germany and compare the results with those obtained by the commonly used Bayesian disease mapping method of Besag, York, and Mollié (1991, Annals of the Institute of Statistical Mathematics, 43, 1,59). [source]