International trends in the rate of logistic mortality increase

Meeting Theme: Are sex differences in health expectancy a social issue?BACKGROUND: Thatcher et al. (2010) used the simple logistic model with two parameters, which is known to fit data on old-age mortality well (Thatcher 1999), to investigate the old-age mortality compression and estimated the rate of logistic mortality increase, denoted by b, for ages 70-90. They concluded that if logit m(x) tends to fall faster at younger ages, then the slope b of the logit line will become steeper and mortality compression will occur. In this paper, we aim to estimate the rate of logistic mortality increase, denoted by b, for ages 70-90 in 23 countries with good and acceptable quality of data from Human Mortality Database and examine whether there is a universal trend in b. METHODS: We adopt a special case of the logistic model of mortality, which has only two parameters as does the Lexis model, and it is usually written in the form of model (1) μ(x) = a ebx / (1 + a ebx) (1) RESULTS: Our results show that the rate of logistic increase has steadily risen for females and males from about 0.10 in the 1950s to about 0.13 in recent years for most established market-economy countries in Europe as shown in group A (19 European countries). Among males, the value of parameter b is about 0.02 smaller than that for females and the rate of logistic mortality increase always lags behind females about 20 years. However, for Japanese females, although the increase was similar to the common pattern from 0.10 in 1947 to 0.13 in 1984, then the value of parameter b reached the highest 0.14 and became levelling off in the decade 1984-1995. Afterwards, it reverted to the level of 1984. In Canada, b increased at a relatively slower pace from 0.10 in 1950 to 0.12 in 2006 among females, whereas in the US the value of b tended to stay at 0.10-0.11 throughout the whole period 1921-2006. In Australia, b for females fluctuated around 0.10-0.11 before 1980, then a noticeable increase was observed from 0.12 in 1980 to 0.14 in 2007. CONCLUSIONS: The results show that the rate of logistic increase has steadily risen for females and males from about 0.10 in the 1950s to about 0.13 in recent years for most established market-economy countries. Deviant patterns such as slow increase, plateau and decrease are observed for some periods in Australia, Canada, Denmark, Japan and the USA. Possible reasons for those dominant and deviant trends are discussed.postprin

Depressive Symptoms in Late Life: The Role of Sociodemographic Factors, Retirement Timing, and Post-Acute Care

The mental well-being of older Americans is a pressing public health concern given the aging population and recent increases in midlife suicide and substance use. Depressive symptoms specifically are a common cause of poor quality of life in old age, and one of the leading causes of disability. This dissertation uses nationally-representative longitudinal data from the Health and Retirement Study to improve understandings of depressive symptoms in mid- and late life, their social patterning, and their intersection with post-hospital recoveries. In Chapter 2, I used mixed-effect models to characterize population trends in how depressive symptoms change over ages 51-90 by gender, race/ethnicity, educational attainment, and birth cohort. This research highlighted large disparities in depressive symptoms in midlife by educational attainment, pointing to the importance of early life exposures for late life health. Results also reaffirmed mental health concerns about recent birth cohorts. Looking at a key life event for this age group, I next focused on retirement timing. This research examined how expectations about full time work at age 62, reported between ages 51-61, align with realized labor force status to determine whether unmet expectations about retirement timing relate to depressive symptoms across sociodemographic groups. The results revealed that unmet retirement expectations are more common among Hispanic and Black Americans compared to White Americans. In addition, those of low educational attainment were at high risk of unexpectedly not working at age 62. Interestingly, unexpectedly working was not associated with depressive symptoms, pointing to the benefits of work for mental health at older ages and the resilience of those adapting to staying in the labor force. Unexpectedly not working was associated with a small increase in depressive symptoms at age 62, which was explained by health declines between expectations and reaching age 62. Future research attention should be directed at mitigating health-related early labor force departures, which differentially occur among disadvantaged groups in America. Finally, I linked survey data from the Health and Retirement Study to Medicare claims data to consider the role of depressive symptoms in recovering from acute hospitalizations. I tested whether different post-acute care settings might mitigate the association between depressive symptoms and poor health outcomes – hospital readmissions, falls, and mortality. Risk for 30-day hospital readmissions increased with increasing depressive symptoms for those recovering at home with or without home health, but not for patients in inpatient rehabilitation settings such as Skilled Nursing Facilities. Post-acute care settings did not modify the relationships between depressive symptoms and each of falls or mortality; therefore, referring depressed patients to inpatient rehabilitation settings could help hospitals avoid financial penalties for readmissions, but will not improve patients’ risks for falls or mortality. Together, this research provides a rich interdisciplinary look at social factors related to depressive symptoms in the aging population and gives insights into one aspect of health services that may address the harmful repercussions of depressive symptoms on other health outcomes.PHDHealth Services Organization & PolicyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/163101/1/lrabrams_1.pd

Black Hearts Matter: A Comparative Study of Sociodemographic, Clinical, and Psychosocial Characteristics in Black and White Persons With Heart Failure

Heart failure (HF) is a chronic, progressive, debilitating illness that disproportionately affects Black individuals, often leading to poor quality of life (QOL). Various sociodemographic, clinical, and psychological characteristics are related to QOL in patients with HF. Because most studies do not include representative Black samples or report findings from racial subgroup analyses, these relationships and any existing racial differences are not well understood. The purpose of this descriptive, comparative study was to explore the relationships among sociodemographic, clinical, and psychological characteristics and QOL in patients with HF and to determine if there were racial differences between Black and White individuals. Mean participant age was 56.29 (SD = 12.42). SPSS 27.0 was the program used to conduct secondary data analysis. Among the sociodemographic characteristics, racial differences were apparent in age, gender, and marital status. Racial differences in ejection fraction, New York Heart Association Classification, comorbidities, and functional status emerged as clinical characteristics. Race was not significantly associated with QOL. Physical functioning and anxiety were significant predictors of QOL in the initial analysis. However, in the full model, older age and greater depression remained significant, suggesting they were the strongest predictors of QOL. Patients with HF should undergo regular screening for depression and anxiety. Future researchers should explore sociodemographic, clinical, and psychological characteristics in larger samples; consider the timing and measurement approaches for depression, anxiety, and QOL; and further explore racial differences

Guidelines for developing and reporting machine learning predictive models in biomedical research : a multidisciplinary view

BACKGROUND: As more and more researchers are turning to big data for new opportunities of biomedical discoveries, machine learning models, as the backbone of big data analysis, are mentioned more often in biomedical journals. However, owing to the inherent complexity of machine learning methods, they are prone to misuse. Because of the flexibility in specifying machine learning models, the results are often insufficiently reported in research articles, hindering reliable assessment of model validity and consistent interpretation of model outputs. OBJECTIVE: To attain a set of guidelines on the use of machine learning predictive models within clinical settings to make sure the models are correctly applied and sufficiently reported so that true discoveries can be distinguished from random coincidence. METHODS: A multidisciplinary panel of machine learning experts, clinicians, and traditional statisticians were interviewed, using an iterative process in accordance with the Delphi method. RESULTS: The process produced a set of guidelines that consists of (1) a list of reporting items to be included in a research article and (2) a set of practical sequential steps for developing predictive models. CONCLUSIONS: A set of guidelines was generated to enable correct application of machine learning models and consistent reporting of model specifications and results in biomedical research. We believe that such guidelines will accelerate the adoption of big data analysis, particularly with machine learning methods, in the biomedical research community

Improving Depression Screening for Clinical Staff in a Psychiatric Rehabilitation Facility: A Quality Improvement Project

Abstract Background: Depression is the most common of mental disorders in the United States affecting a significant portion of the population. Despite the serious consequences of untreated depression, depression screening remains a challenge across healthcare settings prompting the United States Prevention Task Services to develop strong recommendations to improve screening and treatment. Yet, despite those recommendations, lack of knowledge about depression screening continues to impede this process. The presence of substance use in individuals affected by depression worsens the severity of either condition alone. Considering the frequency of co-occurring substance use and depression, it becomes vital that staff working at substance abuse facilities receive adequate training to improve depression screening skills in this sub-population. Purpose: The purpose of this quality improvement project was to increase knowledge of depression screening skills for clinical staff working at a psychiatric rehabilitation facility. Methods: A total of 15 participants completed an online pretest survey to assess their baseline knowledge on depression screening. This was followed by a virtual education module delivered online via PowerPoint presentation. Then, 4 weeks after, participants completed an online posttest survey to evaluate knowledge gained. Results: Pretest survey results revealed knowledge deficit regarding guidelines about depression screening, depression screening skills, and a misguided attitude and negative perception regarding depression. Posttest shows significant improvement in all categories with an overall improvement of 41%. Conclusion: The overwhelming improvement in scores shows the effectiveness of educational interventions to improve depression screening skills and competence and the impact of evidence based training overall in improving patient care

In vivo monitoring of therapeutic efficacy and virulence profile by bioluminescent Klebsiella pneumoniae.

Klebsiella pneumoniae causes an acute respiratory infection in human with severe outcomes and high mortality rates even with antibiotic treatment. Even with its critical clinical importance, few virulence systems have been identified for K. pneumoniae limiting the development of new therapeutic strategies. Accordingly, we performed Next Generation sequencing for the strain ATCC 43816, a virulent strain in mouse respiratory disease models, and compared its genomic data with two previously sequenced strains NTUH-K2044 and MGH 78578 for the purpose of identifying genes required for colonizing host lungs. Furthermore, the virulence potential of the three K. pneumoniae strains were tested in a mouse model of pulmonary disease uniquely generated by our group to insure the specific delivery of an inoculum into host lungs allowing for studying diseases associated specifically with the lower respiratory tract. To monitor disease progression noninvasively, a bioluminescent K. pneumoniae strain was engineered which allowed for monitoring meropenem therapeutic efficacy against the bacteria in real time. A transposon mutant library was generated in the bioluminescent strain and introduced into mice lungs in order identify critical fitness factors required by K. pneumoniae to survive the selective pressure of host lung. The attenuation of known and potential virulence factors, including capsular polysaccharide (CPS) and type 6 secretion systems (T6SSs), were tested in our lung-specific murine model of respiratory disease. Similar to previous findings, manC capsule mutant was attenuated in our lung-specific disease model whereas for the vgrG T6SSs mutants, only cluster one illustrated some potential attenuation in the host, and future studies will be conducted to confirm these outcomes. K. pneumoniae is thought to be an extracellular pathogen but we have provided the first evidence suggesting that this dogma might not be entirely true by demonstrating the capability of the bacteria to proliferate within cultured macrophages in addition to the ability of a subpopulation of K. pneumoniae to become intracellular within mice lungs. Further studies will need to be conducted to identify the role(s) of the intracellular lifestyle for K. pneumoniae during the pulmonary disease

The Epidemiology of post-traumatic seizures following moderate to severe traumatic brain injury

Though death rates due to traumatic brain injury (TBI) are decreasing in the United Statues, TBI remains a significant public health problem. Individuals who survive moderate and severe TBI become at risk of developing secondary complications, including post-traumatic seizures (PTS). PTS are well-recognized sequelae of TBI. Despite previous research, there remains a high degree of variability in who will develop PTS and no approved prophylactic medications to prevent late PTS exist. Late PTS is associated with significant morbidity and worse outcomes following TBI. Therefore, it is of public health importance to understand the characteristics of individuals with PTS, identify factors to improve prognostication, and explore novel risk factors to support a personalized medicine approach. Using the Traumatic Brain Injury Model Systems, we examined the incidence of immediate (7 days post-injury) PTS. Incidence of new onset seizures was highest immediately (8.9%) and one-year (9.2%) post-injury. Late PTS prevalence surpassed 20% at five-years post-injury. Incidence was stratified by potential risk factors and relative risk calculated. Individuals with immediate but not early seizures had a significantly greater incidence of late PTS compared to individuals not seizing during acute hospitalization. We then developed and internally validated prognostic models for PTS during acute hospitalization, at one-year, and two-years post-TBI. We identified multiple variables, including novel factors such as pre-injury mental health conditions, predictive of PTS. Year one and two models showed fair-to-good ability to discriminate PTS, supporting the idea that more accurate prognostication of late PTS can be accomplished. Lastly, we examined genetic variation in neuronal glutamate transporter genes as risk factors for PTS. We identified genetic variants significantly associated with increased PTS risk, after controlling for known risk factors. The relative effect size of the genetic markers suggests these variants may be significant predictors of PTS and may improve prognostic model reliability and validity. Classifying subpopulations at high-risk for PTS could facilitate research regarding the effectiveness of tiered prophylaxis and novel pharmacological interventions, improving prevention and treatment. Together, findings from the current work may affect future research and programmatic decisions, positively impacting those at risk for PTS

Acute lung injury in paediatric intensive care: course and outcome

Introduction: Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) carry a high morbidity and mortality (10-90%). ALI is characterised by non-cardiogenic pulmonary oedema and refractory hypoxaemia of multifactorial aetiology [1]. There is limited data about outcome particularly in children. Methods This retrospective cohort study of 85 randomly selected patients with respiratory failure recruited from a prospectively collected database represents 7.1% of 1187 admissions. They include those treated with High Frequency Oscillation Ventilation (HFOV). The patients were admitted between 1 November 1998 and 31 October 2000. Results: Of the 85, 49 developed acute lung injury and 47 had ARDS. There were 26 males and 23 females with a median age and weight of 7.7 months (range 1 day-12.8 years) and 8 kg (range 0.8-40 kg). There were 7 deaths giving a crude mortality of 14.3%, all of which fulfilled the Consensus I [1] criteria for ARDS. Pulmonary occlusion pressures were not routinely measured. The A-a gradient and PaO2/FiO2 ratio (median + [95% CI]) were 37.46 [31.82-43.1] kPa and 19.12 [15.26-22.98] kPa respectively. The non-survivors had a significantly lower PaO2/FiO2 ratio (13 [6.07-19.93] kPa) compared to survivors (23.85 [19.57-28.13] kPa) (P = 0.03) and had a higher A-a gradient (51.05 [35.68-66.42] kPa) compared to survivors (36.07 [30.2-41.94]) kPa though not significant (P = 0.06). Twenty-nine patients (59.2%) were oscillated (Sensormedics 3100A) including all 7 non-survivors. There was no difference in ventilation requirements for CMV prior to oscillation. Seventeen of the 49 (34.7%) were treated with Nitric Oxide including 5 out of 7 non-survivors (71.4%). The median (95% CI) number of failed organs was 3 (1.96-4.04) for non-survivors compared to 1 (0.62-1.62) for survivors (P = 0.03). There were 27 patients with isolated respiratory failure all of whom survived. Six (85.7%) of the non-survivors also required cardiovascular support.Conclusion: A crude mortality of 14.3% compares favourably to published data. The A-a gradient and PaO2/FiO2 ratio may be of help in morbidity scoring in paediatric ARDS. Use of Nitric Oxide and HFOV is associated with increased mortality, which probably relates to the severity of disease. Multiple organ failure particularly respiratory and cardiac disease is associated with increased mortality. ARDS with isolated respiratory failure carries a good prognosis in children