Loni Philip Tabb

Mobility, Disability, and Social Engagement in Older Adults

Objective: To examine cross sectional associations between mobility with or without disability and social engagement in a community-based sample of older adults. Methods: Social engagement of participants (n = 676) was outside the home (participation in organizations and use of senior centers) and in home (talking by phone and use of Internet). Logistic or proportional odds models evaluated the association between social engagement and position in the disablement process (no mobility limitations, mobility limitations/no disability, and mobility limitations/disability). Results: Low mobility was associated with lower level of social engagement of all forms (Odds ratio (OR) = 0.59, confidence intervals (CI): 0.41-0.85 for organizations; OR = 0.67, CI: 0.42-1.06 for senior center; OR = 0.47, CI: 0.32-0.70 for phone; OR = 0.38, CI: 0.23-0.65 for Internet). For social engagement outside the home, odds of engagement were further reduced for individuals with disability. Discussion: Low mobility is associated with low social engagement even in the absence of disability; associations with disability differed by type of social engagement.

Performance Outcomes After Repair of Complete Achilles Tendon Ruptures in National Basketball Association Players

Background: A complete rupture of the Achilles tendon is a devastating injury. Variables affecting return to competition and performance changes for National Basketball Association (NBA) players are not readily evident. Hypothesis: Players in the NBA who ruptured their Achilles tendons and who underwent surgical repair would have more experience in the league, and the performance of those who were able to return to competition would be decreased when compared with their performance before injury and with their control-matched peers. Study Design: Cohort study; Level of evidence, 3. Methods: Data for 18 basketball players with Achilles tendon repair over a 23-year period (1988-2011) were obtained from injury reports, press releases, and player profiles. Variables included age, body mass index (BMI), player position, and number of years playing in the league. Individual season statistics were obtained, and the NBA Player Efficiency Rating (PER) was calculated for 2 seasons before and after injury. Controls were matched by playing position, number of seasons played, and performance statistics. Univariate and multivariate analyses were performed to assess the effect of each factor. Results: At the time of injury, the average age was 29.7 years, average BMI was 25.6, and average playing experience was 7.6 years. Seven players never returned to play an NBA game, whereas 11 players returned to play 1 season, with 8 of those players returning for ≥2 seasons. Players who returned missed an average of 55.9 games. The PER was reduced by 4.57 (P = .003) in the first season and by 4.38 (P = .010) in the second season. When compared with controls, players demonstrated a significant decline in the PER the first season (P = .038) and second season (P = .081) after their return. Conclusion: The NBA players who returned to play after repair of complete Achilles tendon ruptures showed a significant decrease in playing time and performance. Thirty-nine percent of players never returned to play.

Characterization of a Drosophila Alzheimer's Disease Model: Pharmacological Rescue of Cognitive Defects

Transgenic models of Alzheimers disease (AD) have made significant contributions to our understanding of AD pathogenesis, and are useful tools in the development of potential therapeutics. The fruit fly, Drosophila melanogaster, provides a genetically tractable, powerful system to study the biochemical, genetic, environmental, and behavioral aspects of complex human diseases, including AD. In an effort to model AD, we over-expressed human APP and BACE genes in the Drosophila central nervous system. Biochemical, neuroanatomical, and behavioral analyses indicate that these flies exhibit aspects of clinical AD neuropathology and symptomology. These include the generation of Aβ40 and Aβ42, the presence of amyloid aggregates, dramatic neuroanatomical changes, defects in motor reflex behavior, and defects in memory. In addition, these flies exhibit external morphological abnormalities. Treatment with a γ-secretase inhibitor suppressed these phenotypes. Further, all of these phenotypes are present within the first few days of adult fly life. Taken together these data demonstrate that this transgenic AD model can serve as a powerful tool for the identification of AD therapeutic interventions.

Comparative Effectiveness of Empiric β-Lactam Monotherapy and β-Lactam-Macrolide Combination Therapy in Children Hospitalized with Community-Acquired Pneumonia.

OBJECTIVE To determine the comparative effectiveness of β-lactam monotherapy and β-lactam and macrolide combination therapy on clinical outcomes in the treatment of children hospitalized with community-acquired pneumonia (CAP). STUDY DESIGN This multicenter retrospective cohort study included children aged 1-18 years who were hospitalized with CAP and received β-lactam antibiotic therapy either alone or in combination with a macrolide. Data were obtained from the Pediatric Health Information System. Associations between empiric antibiotic therapy and hospital readmission for the same episode of pneumonia were estimated using exact logistic regression. Associations between empiric antibiotic therapy and length of hospital stay were estimated using a generalized estimating equation with negative binomial distribution. RESULTS There were 20 743 patients hospitalized with CAP. Of these, 24% received β-lactam and macrolide combination therapy on admission. Compared with children who received β-lactam monotherapy, children who received β-lactam plus macrolide combination therapy were 20% less likely to stay in the hospital an additional day (adjusted relative risk 0.80; 95% CI, 0.75-0.86) but did not have a different readmission rate (relative risk 0.69; 95% CI, 0.41-1.12). An effect of combination treatment on reduced length of stay was not evident in children <6 years of age but increased with increasing age groups thereafter. CONCLUSION School-aged patients hospitalized with CAP who received β-lactam plus macrolide combination therapy have a shorter length of stay and similar rates of readmission compared with school-aged patients who receive β-lactam monotherapy.

Alcohol beverage control, privatization and the geographic distribution of alcohol outlets

BackgroundWith Pennsylvania currently considering a move away from an Alcohol Beverage Control state to a privatized alcohol distribution system, this study uses a spatial analytical approach to examine potential impacts of privatization on the number and spatial distribution of alcohol outlets in the city of Philadelphia over a long time horizon.MethodsA suite of geospatial data were acquired for Philadelphia, including 1,964 alcohol outlet locations, 569,928 land parcels, and school, church, hospital, park and playground locations. These data were used as inputs for exploratory spatial analysis to estimate the expected number of outlets that would eventually operate in Philadelphia. Constraints included proximity restrictions (based on current ordinances regulating outlet distribution) of at least 200 feet between alcohol outlets and at least 300 feet between outlets and schools, churches, hospitals, parks and playgrounds.ResultsFindings suggest that current state policies on alcohol outlet distributions in Philadelphia are loosely enforced, with many areas exhibiting extremely high spatial densities of outlets that violate existing proximity restrictions. The spatial model indicates that an additional 1,115 outlets could open in Philadelphia if privatization was to occur and current proximity ordinances were maintained.ConclusionsThe study reveals that spatial analytical approaches can function as an excellent tool for contingency-based “what-if” analysis, providing an objective snapshot of potential policy outcomes prior to implementation. In this case, the likely outcome is a tremendous increase in alcohol outlets in Philadelphia, with concomitant negative health, crime and quality of life outcomes that accompany such an increase.

On-Field Performance of National Football League Players After Return From Concussion

Background: There are few data examining the short-term effects of concussions on player performance upon return to play. This study examined changes in on-field performance and the influence of epidemiologic factors on performance and return to play. Hypothesis: On-field performance is different in players who return within 7 days after concussion compared with players who miss at least 1 game. Study Design: Case-control study; Level of evidence, 3. Methods: Players in the National Football League who were active during the 2008 to 2012 seasons were considered for inclusion. Weekly injury reports identified concussed players. All players played in at least 4 games before and after the game of injury (sentinel game) within the year of injury (sentinel year). Players who had missed games secondary to another injury or had sustained a second concussion within the sentinel year were excluded. The players’ league profiles were used to determine age, position, body mass index, career experience, and games missed. ProFootballFocus performance scores determined player ratings. Statistical analysis used 2-sided t tests and both univariate and multivariate logistic regression models. Results: There were a total of 131 concussions in the 124 players who qualified for this study; 55% of these players missed no games. Defensive secondary, wide receiver, and offensive line were the most commonly affected positions. Players who missed at least 1 game were younger and less experienced. Preinjury ProFootballFocus performance scores were similar to postinjury performance in players without games missed (0.16 vs 0.33; P = .129) and players who missed at least 1 game (−0.06 vs 0.10; P = .219). Age, body mass index, experience, and previous concussion did not correlate with changes in postinjury scores (P > .05). Older, more experienced players and players with late-season concussions were more likely to return to play without missing games (P < .05). The odds of returning within 7 days increased by 18% for each career year and by 40% for each game before the sentinel game within the sentinel year; these same odds decreased by 85% after introduction of newer treatment guidelines in 2009. Conclusion: No difference in player performance after concussion was found whether the player did or did not miss games before return. Return without missing games may be associated with experience and timing of injury within a season and less likely after newer guidelines.

Injuries Among Children With Autism Spectrum Disorder

OBJECTIVE We compared risk of injury among children with autism spectrum disorder (ASD) to those without ASD, adjusting for demographic and clinical characteristics. METHODS We used claims data from 2001 to 2009 from a commercial health plan in the United States. A validated ASD case identification algorithm identified 33,565 children (ages 0-20 years) with ASD and 138,876 children without. Counting process models tested the association between ASD status and injury episodes with separate regressions run for children during different age periods. RESULTS Unadjusted results demonstrated that children with ASD had a 12% greater injury risk than children without ASD (hazard ratio [HR] = 1.119; P < .001). After including demographic variables, the HR was 1.03 (P < .05); after controlling for co-occurring conditions, such as seizures, depression, etc, HR decreased to 0.889 (P < .001). For the age period analysis, HR values were as follows: for 0 to 2 years, HR 1.141; 3 to 5 years, HR 1.282; 6 to 10 years, HR not significant; and 11 to 20 years, HR 0.634 (P < .05 for all significant results). CONCLUSIONS Children with ASD have more injuries than children without ASD. After controlling for demographic factors and co-occurring conditions, children with ASD are at lower risk of injury, suggesting that co-occurring conditions or the ways these conditions interact with ASD is related to injuries. Clinicians should understand that injury risk in children with ASD may be driven by co-occurring conditions. Treating these conditions could thus decrease injury risk as well as have other benefits. Injury prevention interventions are especially warranted for younger children with ASD and those with seizures, depression, visual impairment, or attention-deficit disorders.

The spatio-temporal relationship between alcohol outlets and violence before and after privatization: A natural experiment, Seattle, Wa 2010–2013

Alcohol-related violence is a well-documented public health concern, where various individual and community-level factors contribute to this relationship. The purpose of this study is to examine the impact of a significant policy change at the local level, which privatized liquor sales and distribution. Specifically, we explored the relationship between alcohol and violence in Seattle, WA, 2010-2013, via hierarchical spatio-temporal disease mapping models. To measure and map this complex spatio-temporal relationship at the census block group level (n=567), we examined a variety of models using integrated nested Laplace approximations and used the deviance information criterion to gauge model complexity and fit. For each additional off-premises and on-premises alcohol outlet in a given census block group, we found a significant increase of 8% and 5% for aggravated assaults and 6% and 5% for non-aggravated assaults, respectively. Lastly, our maps showed variation in the estimated relative risks across the city of Seattle.

Neighborhood social capital and achieved mobility of older adults

Objective: Evaluate associations of neighborhood social capital and mobility of older adults. Method: A community-based survey (Philadelphia, 2010) assessed mobility (Life-Space Assessment [LSA]; range = 0-104) of older adults (n = 675, census tracts = 256). Social capital was assessed for all adults interviewed from 2002-2010 (n = 13,822, census tracts = 374). Generalized estimating equations adjusted for individual- and neighborhood-level characteristics estimated mean differences and 95% confidence intervals (CIs) in mobility by social capital tertiles. Interactions by self-rated health, living arrangement, and race were tested. Results: Social capital was not associated with mobility after adjustment for other neighborhood characteristics (mean difference for highest versus lowest tertile social capital = 0.79, 95% CI = [−3.3, 4.8]). We observed no significant interactions. In models stratified by race, Black participants had higher mobility in high social capital neighborhoods (mean difference = 7.4, CI = [1.0, 13.7]). Discussion: Social capital may not contribute as much as other neighborhood characteristics to mobility. Interactions between neighborhood and individual-level characteristics should be considered in research on mobility.

Cross-sectional and longitudinal associations of neighbourhood social environment and smoking behaviour: the multiethnic study of atherosclerosis.

Background Social features of neighbourhood environments may influence smoking by creating a stressful environment or by buffering stress through social cohesion. However, the association of the overall neighbourhood social environment (NSE) with smoking, and the association of specific neighbourhood social factors with change in smoking behaviour over time, has rarely been examined. Methods This study included 5856 adults aged 45–84 years from the Multi-Ethnic Study of Atherosclerosis (2000–2012, average follow-up: 7.8 years). Outcomes included current smoking status and smoking intensity (average number of cigarettes smoked per day among baseline smokers). NSE was assessed as a composite score composed of aesthetic quality, safety and social cohesion scales (derived from neighbourhood surveys). Generalised linear mixed models evaluated the association of baseline NSE (composite score and individual scales) with current smoking (modified Poisson models) and smoking intensity (negative binomial models) cross-sectionally and longitudinally. Results Each SD increase in baseline NSE composite score was associated with 13% lower prevalence of smoking at baseline (adjusted prevalence ratio (aPR) 0.87 (95% CI 0.78 to 0.98). Neighbourhood safety and aesthetic quality were similarly associated with lower smoking prevalence (aPR 0.87 (0.78 to 0.97) and aPR 0.87 (0.77 to 0.99), respectively) but the association with social cohesion was weaker or null. No significant associations were observed for smoking intensity among baseline smokers. Baseline NSE was not associated with changes in smoking risk or intensity over time. Conclusions Results suggest that neighbourhood social context influences whether older adults smoke, but does not promote smoking cessation or reduction over time.