Search

Background: Mortality is a key component of the natural history of COVID-19 infection. Surveillance data on COVID-19 deaths and case diagnoses are widely available in the public domain, but they are not used to model time to death because they typically do not link diagnosis and death at an individual level. This paper demonstrates that by comparing the unlinked patterns of new diagnoses and deaths over age and time, age-specific mortality and time to death may be estimated using a statistical method called deconvolution.Methods: Age-specific data were analysed on 816 deaths among 6235 cases over age 50 years in Victoria, Australia, from the period January through December 2020. Deconvolution was applied assuming logistic dependence of case fatality risk (CFR) on age and a gamma time to death distribution. Non-parametric deconvolution analyses stratified into separate age groups were used to assess the model assumptions.Results: It was found that age-specific CFR rose from 2.9% at age 65 years (95% CI:2.2 - 3.5) to 40.0% at age 95 years (CI: 36.6 - 43.6). The estimated mean time between diagnosis and death was 18.1 days (CI: 16.9 - 19.3) and showed no evidence of varying by age (heterogeneity P = 0.97). The estimated 90% percentile of time to death was 33.3 days (CI: 30.4 - 36.3; heterogeneity P = 0.85). The final age-specific model provided a good fit to the observed age-stratified mortality patterns.Conclusions: Deconvolution was demonstrated to be a powerful analysis method that could be applied to extensive data sources worldwide. Such analyses can inform transmission dynamics models and CFR assessment in emerging outbreaks. Based on these Australian data it is concluded that death from COVID-19 occurs within three weeks of diagnosis on average but takes five weeks in 10% of fatal cases. Fatality risk is negligible in the young but rises above 40% in the elderly, while time to death does not seem to vary by age. [ABSTRACT FROM AUTHOR]

Aims: Valid data on the incidence of inflammatory bowel disease (IBD) in children and adolescents in Germany have not yet been published. Unpublished data of the Pediatric IBD Registry of Saxony (primary data source) have shown a decrease in age-specific incidence rates after the 14th year of age; therefore, a second data source was collected from adult gastroenterologists in Leipzig.Methods: All patients up to 25 years of age with a newly diagnosed IBD from adult gastroenterologists in Leipzig between 2005 and 2009 were included in the second data source: a total of 150 young patients with only two patients before age of 16 and 11 patients before age of 18 years.Results: Using a second data source, the incidence of IBD in children and adolescents up to the completion of the 18th year, as determined by IBD Registry, was corrected from 6.6/100,000 (95%-CI 5.4-8.4) to an actual incidence of 11.0/100,000 (95%-CI 9.1-12.9). Age-specific incidence of IBD was also corrected, increasing continuously until the 18th year was completed.Conclusions: Nearly all patients up to 15 years (completeness 87.5%) were recorded by pediatricians to the IBD Registry. The actual incidence up to the age of 18 years for IBD in Leipzig is one of the highest worldwide. To obtain valid epidemiologic data up to the age of 18, the inclusion of adult gastroenterologists are necessary. [ABSTRACT FROM AUTHOR]

We analyzed mesothelioma incidence in the Surveillance, Epidemiology, and End Results (SEER) database over the period 1973–2005 using extensions of the age–period–cohort (APC) models. In these analyses, the usual non-specific age effects of the conventional APC models were replaced by hazard functions derived from two multistage models of carcinogenesis, the Armitage–Doll model and the two-stage clonal expansion (TSCE) model. The extended APC models described the incidence data on pleural and peritoneal mesotheliomas well. After adjustment for temporal trends, the data suggest that the age-specific incidence rates of both pleural and peritoneal mesotheliomas are identical in men and women. Driven largely by birth cohort effects, age-adjusted rates of pleural mesothelioma among men rose from about 7.5 per million person-years in 1973 to about 20 per million person-years in the early 1990s and appear to be stable or declining thereafter. Age-adjusted rates of pleural mesothelioma among women have remained more or less constant at about 2.5 per million person-years over the period 1973–2005. Age-adjusted rates for peritoneal mesothelioma in both men (1.2 per million person-years) and women (0.8 per million person-years) exhibit no temporal trends over the period of the study. We estimate that approximately 94,000 cases of pleural and 15,000 cases of peritoneal mesothelioma will occur in the US over the period 2005–2050. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a multilevel disease of the motor neuron system. The mechanisms triggering disease onset should be considered separately from those facilitating its spread and motor neuron death. In 2005, I brought together clinical and epidemiological evidence to support the hypothesis that acquired nucleic acid changes may trigger sporadic ALS. Since 2005, the conceptual foundations for this hypothesis have been strengthened. The journal Amyotrophic Lateral Sclerosis was renamed Amyotrophic Lateral Sclerosis & Frontotemporal Degeneration. The focal onset, with simultaneous initial maximal upper and lower motor neuron involvement in the region of onset, and patterns of spread, were characterized further. Clues from the epidemiology of sporadic ALS were affirmed by quantitative analysis, including the increase in disease incidence with age, suggesting accrual of time-dependent changes, and the confirmation of smoking as an established risk factor. Additional observations support the conclusion that accrued somatic mutations trigger onset of ALS. Muscle Nerve 53: 842-849, 2016. [ABSTRACT FROM AUTHOR]

Incidence is an important epidemiological concept most suitably studied using an incident cohort study. However, data are often collected from the more feasible prevalent cohort study, whereby diseased individuals are recruited through a cross-sectional survey and followed in time. In the absence of temporal trends in survival, we derive an efficient nonparametric estimator of the cumulative incidence based on such data and study its asymptotic properties. Arbitrary calendar time variations in disease incidence are allowed. Age-specific incidence and adjustments for both stratified sampling and temporal variations in survival are also discussed. Simulation results are presented and data from the Canadian Study of Health and Aging are analysed to infer the incidence of dementia in the Canadian elderly population. [ABSTRACT FROM PUBLISHER]