Effectiveness of inactivated influenza vaccines in preventing influenza-associated deaths and hospitalizations among Ontario residents aged ≥ 65 years: estimates with generalized linear models accounting for healthy vaccinee effects.

BACKGROUND: Estimates of the effectiveness of influenza vaccines in older adults may be biased because of difficulties identifying and adjusting for confounders of the vaccine-outcome association. We estimated vaccine effectiveness for prevention of serious influenza complications among older persons by using methods to account for underlying differences in risk for these complications. METHODS: We conducted a retrospective cohort study among Ontario residents aged ≥ 65 years from September 1993 through September 2008. We linked weekly vaccination, hospitalization, and death records for 1.4 million community-dwelling persons aged ≥ 65 years. Vaccine effectiveness was estimated by comparing ratios of outcome rates during weeks of high versus low influenza activity (defined by viral surveillance data) among vaccinated and unvaccinated subjects by using log-linear regression models that accounted for temperature and time trends with natural spline functions. Effectiveness was estimated for three influenza-associated outcomes: all-cause deaths, deaths occurring within 30 days of pneumonia/influenza hospitalizations, and pneumonia/influenza hospitalizations. RESULTS: During weeks when 5% of respiratory specimens tested positive for influenza A, vaccine effectiveness among persons aged ≥ 65 years was 22% (95% confidence interval [CI], -6%-42%) for all influenza-associated deaths, 25% (95% CI, 13%-37%) for deaths occurring within 30 days after an influenza-associated pneumonia/influenza hospitalization, and 19% (95% CI, 4%-31%) for influenza-associated pneumonia/influenza hospitalizations. Because small proportions of deaths, deaths after pneumonia/influenza hospitalizations, and pneumonia/influenza hospitalizations were associated with influenza virus circulation, we estimated that vaccination prevented 1.6%, 4.8%, and 4.1% of these outcomes, respectively. CONCLUSIONS: By using confounding-reducing techniques with 15 years of provincial-level data including vaccination and health outcomes, we estimated that influenza vaccination prevented ~4% of influenza-associated hospitalizations and deaths occurring after hospitalizations among older adults in Ontario

Supernova Properties from Shock Breakout X-rays

We investigate the potential of the upcoming LOBSTER space observatory (due circa 2009) to detect soft X-ray flashes from shock breakout in supernovae, primarily from Type II events. LOBSTER should discover many SN breakout flashes, although the number is sensitive to the uncertain distribution of extragalactic gas columns. X-ray data will constrain the radii of their progenitor stars far more tightly than can be accomplished with optical observations of the SN light curve. We anticipate the appearance of blue supergiant explosions (SN 1987A analogs), which will uncover a population of these underluminous events. We consider also how the mass, explosion energy, and absorbing column can be constrained from X-ray observables alone and with the assistance of optically-determined distances. These conclusions are drawn using known scaling relations to extrapolate, from previous numerical calculations, the LOBSTER response to explosions with a broad range of parameters. We comment on a small population of flashes with 0.2 < z < 0.8 that should exist as transient background events in XMM, Chandra, and ROSAT integrations.Comment: 14 pages, 9 figures, accepted by MNRAS, presented at AAS 203rd meetin

The association between multimorbidity and hospitalization is modified by individual demographics and physician continuity of care: a retrospective cohort study

Abstract Background Multimorbidity poses a significant clinical challenge and has been linked to greater health services use, including hospitalization; however, we have little knowledge about the influence of contextual factors on outcomes in this population. Objectives: To describe the extent to which the association between multimorbidity and hospitalization is modified by age, gender, primary care practice model, or continuity of care (COC) among adults with at least one chronic condition. Methods A retrospective cohort study with linked population-based administrative data. Setting: Ontario, Canada. Cohort: All individuals 18 and older with at least one of 16 priority chronic conditions as of April 1, 2009 (baseline). Main Outcome Measures: Any hospitalization, 3 or more hospitalizations, non-medical discharge delay, and 30-day readmission within the 1 year following baseline. Results Of 5,958,514 individuals, 484,872 (8.1 %) experienced 646,347 hospitalizations. There was a monotonic increase in the likelihood of hospitalization and related outcomes with increasing multimorbidity which was modified by age, gender, and COC but not primary care practice model. The effect of increasing multimorbidity was greater in younger adults than older adults and in those with lower COC than with higher COC. The effect of increasing multimorbidity on hospitalization was greater in men than women but reversed for the other outcomes. Conclusions The effect of multimorbidity on hospitalization is influenced by age and gender, important considerations in the development of person-centred care models. Greater continuity of physician care lessened the effect of multimorbidity on hospitalization, further demonstrating the need for care continuity across providers for people with chronic conditions

The increasing burden and complexity of multimorbidity

Abstract Background Multimorbidity, the co-occurrence of two or more chronic conditions, is common among older adults and is known to be associated with high costs and gaps in quality of care. Population-based estimates of multimorbidity are not readily available, which makes future planning a challenge. We aimed to estimate the population-based prevalence and trends of multimorbidity in Ontario, Canada and to examine patterns in the co-occurrence of chronic conditions. Methods This retrospective cohort study includes all Ontarians (aged 0 to 105 years) with at least one of 16 common chronic conditions. Descriptive statistics were used to examine and compare the prevalence of multimorbidity by age and number of conditions in 2003 and 2009. The co-occurrence of chronic conditions among individuals with multimorbidity was also explored. Results The prevalence of multimorbidity among Ontarians rose from 17.4% in 2003 to 24.3% in 2009, a 40% increase. This increase over time was evident across all age groups. Within individual chronic conditions, multimorbidity rates ranged from 44% to 99%. Remarkably, there were no dominant patterns of co-occurring conditions. Conclusion The high prevalence of multimorbidity and numerous combinations of conditions suggests that single, disease-oriented management programs may be less effective or efficient tools for high quality care compared to person-centered approaches

Maternal opioid treatment after delivery and risk of adverse infant outcomes: population based cohort study.

OBJECTIVE: To examine whether maternal opioid treatment after delivery is associated with an increased risk of adverse infant outcomes. DESIGN: Population based cohort study in Ontario, Canada. 865 691 mother-infant pairs discharged from hospital alive within seven days of delivery from 1 September 2012 to 31 March 2020. Each mother who filled an opioid prescription within seven days of discharge was propensity score matched to a mother who did not. MAIN OUTCOME MEASURES: The primary outcome was hospital readmission of infants for any reason within 30 days of their mother filling an opioid prescription (index date). Infant related secondary outcomes were any emergency department visit, hospital admission for all cause injury, admission to a neonatal intensive care unit, admission with resuscitation or assisted ventilation, and all cause death. RESULTS: 85 675 mothers (99.8% of the 85 852 mothers prescribed an opioid) who filled an opioid prescription within seven days of discharge after delivery were propensity score matched to 85 675 mothers who did not. Of the infants admitted to hospital within 30 days, 2962 (3.5%) were born to mothers who filled an opioid prescription compared with 3038 (3.5%) born to mothers who did not. Infants of mothers who were prescribed an opioid were no more likely to be admitted to hospital for any reason than infants of mothers who were not prescribed an opioid (hazard ratio 0.98, 95% confidence interval 0.93 to 1.03) and marginally more likely to be taken to an emergency department in the subsequent 30 days (1.04, 1.01 to 1.08), but no differences were found for any other adverse infant outcomes and there were no infant deaths. CONCLUSIONS: Findings from this study suggest no association between maternal opioid prescription after delivery and adverse infant outcomes, including death

Predicted number of cases averted by influenza vaccination, by study outcome.

a<p>Percent averted among vaccinees is calculated as (cases averted / [total cases in the vaccinated population during weeks of influenza virus circulation + cases averted]) * 100</p

Proportion of outcomes that were influenza A-associated per season and overall.

<p>Percentage of all-cause mortality, 30-day pneumonia/influenza mortality, and pneumonia/influenza hospitalizations that were estimated to be influenza-associated during periods of influenza A circulation are indicated in the green, blue, and red columns, respectively.</p

Number of individuals included in the study, influenza vaccinations, and outcomes for each study year.

<p>Number of individuals included in the study, influenza vaccinations, and outcomes for each study year.</p

Weekly trends of influenza viral surveillance outcome rates among individuals aged ≥65 years.

<p>In the top three panels, weekly outcome rates are indicated by red symbols for unvaccinated individuals and blue symbols for vaccinated individuals; the size of the symbol reflects the number of individuals in a category. The panels show all-cause mortality, 30-day pneumonia/influenza mortality, and pneumonia/influenza hospitalization from top to bottom, respectively. In the bottom panel, weekly percentages of specimens testing positive for either influenza A or B are represented by gray and black bars (respectively). The sum of the black bar and gray bar shows the total percent positive for the week (i.e., the data for influenza A and B are <i>not</i> overlaid).</p

Estimates of vaccine effectiveness (VE) for the prevention of influenza A-associated outcomes in community-dwelling Ontario residents aged ≥65 years (95% confidence interval [CI]) during weeks when 5% or 10% of respiratory specimens tested positive for influenza viruses.

<p>Estimates of vaccine effectiveness (VE) for the prevention of influenza A-associated outcomes in community-dwelling Ontario residents aged ≥65 years (95% confidence interval [CI]) during weeks when 5% or 10% of respiratory specimens tested positive for influenza viruses.</p