Mortality After the Hospitalization of a Spouse

Background: The illness of a spouse can affect the health of a caregiving partner. We examined the association between the hospitalization of a spouse and a partner’s risk of death among elderly people. Methods: We studied 518,240 couples who were enrolled in Medicare in 1993. We used Cox regression analysis and fixed-effects (case–time–control) methods to assess hospitalizations and deaths during nine years of follow-up. Results: Overall, 383,480 husbands (74 percent) and 347,269 wives (67 percent) were hospitalized at least once, and 252,557 husbands (49 percent) and 156,004 wives (30 percent) died. Mortality after the hospitalization of a spouse varied according to the spouse’s diagnosis. Among men, 6.4 percent died within a year after a spouse’s hospitalization for colon cancer, 6.9 percent after a spouse’s hospitalization for stroke, 7.5 percent after a spouse’s hospitalization for psychiatric disease, and 8.6 percent after a spouse’s hospitalization for dementia. Among women, 3.0 percent died within a year after a spouse’s hospitalization for colon cancer, 3.7 percent after a spouse’s hospitalization for stroke, 5.7 percent after a spouse’s hospitalization for psychiatric disease, and 5.0 percent after a spouse’s hospitalization for dementia. After adjustment for measured covariates, the risk of death for men was not significantly higher after a spouse’s hospitalization for colon cancer (hazard ratio, 1.02; 95 percent confidence interval, 0.95 to 1.09) but was higher after hospitalization for stroke (hazard ratio, 1.06; 95 percent confidence interval, 1.03 to 1.09), congestive heart failure (hazard ratio, 1.12; 95 percent confidence interval, 1.07 to 1.16), hip fracture (hazard ratio, 1.15; 95 percent confidence interval, 1.11 to 1.18), psychiatric disease (hazard ratio, 1.19; 95 percent confidence interval, 1.12 to 1.26), or dementia (hazard ratio, 1.22; 95 percent confidence interval, 1.12 to 1.32). For women, the various risks of death after a spouse’s hospitalization were similar. Overall, for men, the risk of death associated with a spouse’s hospitalization was 22 percent of that associated with a spouse’s death (95 percent confidence interval, 17 to 27 percent); for women, the risk was 16 percent of that associated with death (95 percent confidence interval, 8 to 24 percent). Conclusions: Among elderly people hospitalization of a spouse is associated with an increased risk of death, and the effect of the illness of a spouse varies among diagnoses. Such interpersonal health effects have clinical and policy implications for the care of patients and their families.Sociolog

On-Chip Cavity Optomechanical Coupling

On-chip cavity optomechanics, in which strong co-localization of light and mechanical motion is engineered, relies on efficient coupling of light both into and out of the on-chip optical resonator. Here we detail our particular style of tapered and dimpled optical fibers, pioneered by the Painter group at Caltech, which are a versatile and reliable solution to efficient on-chip coupling. First, a brief overview of tapered, single mode fibers is presented, in which the single mode cutoff diameter is highlighted. The apparatus used to create a dimpled tapered fiber is then described, followed by a comprehensive account of the procedure by which a dimpled tapered fiber is produced and mounted in our system. The custom-built optical access vacuum chambers in which our on-chip optomechanical measurements are performed are then discussed. Finally, the process by which our optomechanical devices are fabricated and the method by which we explore their optical and mechanical properties is explained. It is our expectation that this manuscript will enable the novice to develop advanced optomechanical experiments.Comment: 31 pages, 9 figure

Overall Perceived Health Predicts Risk of Hospitalizations and Death in Adults With Heart Failure: A Prospective Longitudinal Study

Background Patient overall perception of health may provide an effective early warning for risk of hospitalization and death among heart failure patients. Objective Determine whether overall perceived health predicts all-cause hospitalization or death in heart failure patients after adjusting for confounding factors in a sample of adults with heart failure. Design Prospective, longitudinal, observational study. Settings Three outpatient urban settings in the northeast United States between 2007 and 2010. Participants Adults with chronic Stage C heart failure confirmed by echocardiographic and clinical evidence. Methods A secondary analysis was conducted using data collected on 273 Stage C patients with heart failure. Participants in the parent study were followed for 6 months. Overall perceived health was measured by self-report. Hospitalization and death were assessed from electronic hospital records and confirmed with county death records as needed. Cox proportional hazards models were used to examine the association between perceptions of health and rates of hospitalization and death. Results Patients with poor or fair perceived health had over 5.5 times the rate of death or hospitalization over the 6-month period (hazard ratio; 95% confidence interval: 2.0–15.6; p = 0.001) after controlling for model covariates. The predictive ability of perceived health attenuated over time such that at 30-days patients who reported poor or fair perceived health had only 1.2 times the rate of an event and virtually no difference in event rate by 60-days. Conclusions Overall perceived health is a powerful indicator of impending events and can be a quick tool for prioritizing heart failure patients who are at highest risk of imminent death and hospitalization. Questions about perceived health need to be asked of patients regularly in order to have clinical utility

Dynamic panel data modelling using maximum likelihood : an alternative to Arellano-Bond

Incluye bibliografíaEl estimador de Arellano y Bond (1991) es muy popular entre los investigadores empíricos para estimar modelos dinámicos de panel con efectos fijos y regresores endógenos. Sin embargo, dicho estimador puede presentar sesgos cuando el número de unidades del panel (N) es pequeño, especialmente si las variables bajo análisis son persistentes en el tiempo. Este documento discute un estimador de máxima verosimilitud que es asintóticamente equivalente a Arellano y Bond (1991), pero presenta un mejor comportamiento en muestras finitas (cuando N es pequeño). Además, el estimador es fácil de implementar en Stata utilizando el comando xtdpdml, como se describe en el documento complementario Williams et al. (2016), que también analiza otras potenciales ventajas del estimador propuestoThe Arellano and Bond (1991) estimator is widely-used among applied researchers when estimating dynamic panels with fixed effects and predetermined regressors. This estimator might behave poorly in finite samples when the cross-section dimension of the data is small (i.e. small N), especially if the variables under analysis are persistent over time. This paper discusses a maximum likelihood estimator that is asymptotically equivalent to Arellano and Bond (1991) but presents better finite sample behaviour. Moreover, the estimator is easy to implement in Stata using the xtdpdml command as described in the companion paper Williams et al. (2016), which also discusses further advantages of the proposed estimator for practitioner

Microstructural characterisation of biocompatible sol-gel derived vanadium doped TiO2 on Ti substrates

Sol-gel derived pure titania is compared with vanadium and / or aluminium modified titania deposited by spin coating on pure titanium substrates annealed at 300C and 650C. Reflection high-energy electron diffraction indicated the presence of anatase from the surface layers of samples annealed at 300C with a transition to rutile with increasing annealing temperature and addition of vanadium. Cross-sectional transmission electron microscopy indicated a gradation of Ti-O phases through the layer with the dominant presence of rutile. Aluminium was found to inhibit grain growth while vanadium promoted crystallisation

The Impact of State Preemption of Local Smoking Restrictions on Public Health Protections and Changes in Social Norms

Introduction. Preemption is a legislative or judicial arrangement in which a higher level of government precludes lower levels of government from exercising authority over a topic. In the area of smoke-free policy, preemption typically takes the form of a state law that prevents communities from adopting local smoking restrictions. Background. A broad consensus exists among tobacco control practitioners that preemption adversely impacts tobacco control efforts. This paper examines the effect of state provisions preempting local smoking restrictions in enclosed public places and workplaces. Methods. Multiple data sources were used to assess the impact of state preemptive laws on the proportion of indoor workers covered by smoke-free workplace policies and public support for smoke-free policies. We controlled for potential confounding variables. Results. State preemptive laws were associated with fewer local ordinances restricting smoking, a reduced level of worker protection from secondhand smoke, and reduced support for smoke-free policies among current smokers. Discussion. State preemptive laws have several effects that could impede progress in secondhand smoke protections and broader tobacco control efforts. Conclusion. Practitioners and advocates working on other public health issues should familiarize themselves with the benefits of local policy making and the potential impact of preemption

Fears of Violence During Morning Travel to School

PURPOSE: Children\u27s safety as they travel to school is a concern nationwide. We investigated how safe children felt from the risk of being assaulted during morning travel to school. METHODS: Children between 10 and 18 years old were recruited in Philadelphia and interviewed with the aid of geographic information system (GIS) mapping software about a recent trip to school, situational characteristics, and how safe they felt as they travelled based on a 10-point item (1 = very unsafe, 10 = very safe). Ordinal regression was used to estimate the probability of perceiving different levels of safety based on transportation mode, companion type, and neighborhood characteristics. RESULTS: Among 65 randomly selected subjects, routes to school ranged from 7 to 177 minutes (median = 36) and .1-15.1 street miles (median = 1.9), and included between 1-5 transportation modes (median = 2). Among students interviewed, 58.5% felt less than very safe (i.e.,8, for example, was .99 while in a car and .94 while on foot but was .86 and .87 when on a public bus or trolley. Probability was .98 while with an adult but was .72 while with another child and .71 when alone. Also, perceived safety was lower in areas of high crime and high density of off-premise alcohol outlets. CONCLUSIONS: Efforts that target situational risk factors are warranted to help children feel safe over their entire travel routes to school

Required Sample Size to Detect Mediation in 3-Level Implementation Studies

Background: Statistical tests of mediation are important for advancing implementation science; however, little research has examined the sample sizes needed to detect mediation in 3-level designs (e.g., organization, provider, patient) that are common in implementation research. Using a generalizable Monte Carlo simulation method, this paper examines the sample sizes required to detect mediation in 3-level designs under a range of conditions plausible for implementation studies. Method: Statistical power was estimated for 17,496 3-level mediation designs in which the independent variable (X) resided at the highest cluster level (e.g., organization), the mediator (M) resided at the intermediate nested level (e.g., provider), and the outcome (Y) resided at the lowest nested level (e.g., patient). Designs varied by sample size per level, intraclass correlation coefficients of M and Y, effect sizes of the two paths constituting the indirect (mediation) effect (i.e., X→M and M→Y), and size of the direct effect. Power estimates were generated for all designs using two statistical models—conventional linear multilevel modeling of manifest variables (MVM) and multilevel structural equation modeling (MSEM)—for both 1- and 2-sided hypothesis tests. Results: For 2-sided tests, statistical power to detect mediation was sufficient (≥0.8) in only 463 designs (2.6%) estimated using MVM and 228 designs (1.3%) estimated using MSEM; the minimum number of highest-level units needed to achieve adequate power was 40; the minimum total sample size was 900 observations. For 1-sided tests, 808 designs (4.6%) estimated using MVM and 369 designs (2.1%) estimated using MSEM had adequate power; the minimum number of highest-level units was 20; the minimum total sample was 600. At least one large effect size for either the X→M or M→Y path was necessary to achieve adequate power across all conditions. Conclusions: While our analysis has important limitations, results suggest many of the 3-level mediation designs that can realistically be conducted in implementation research lack statistical power to detect mediation of highest-level independent variables unless effect sizes are large and 40 or more highest-level units are enrolled. We suggest strategies to increase statistical power for multilevel mediation designs and innovations to improve the feasibility of mediation tests in implementation research

Sotto Voce: Exploring the Interplay of Conversation and Mobile Audio Spaces

In addition to providing information to individual visitors, electronic guidebooks have the potential to facilitate social interaction between visitors and their companions. However, many systems impede visitor interaction. By contrast, our electronic guidebook, Sotto Voce, has social interaction as a primary design goal. The system enables visitors to share audio information - specifically, they can hear each other's guidebook activity using a technologically mediated audio eavesdropping mechanism. We conducted a study of visitors using Sotto Voce while touring a historic house. The results indicate that visitors are able to use the system effectively, both as a conversational resource and as an information appliance. More surprisingly, our results suggest that the technologically mediated audio often cohered the visitors' conversation and activity to a far greater degree than audio delivered through the open air.Comment: 8 page