Review of Software to Fit Generalized Estimating Equation Regression Models

The impact of time to defibrillation on return of spontaneous circulation in out-of-hospital cardiac arrest patients with recurrent shockable rhythms

OBJECTIVE

Optimal timing for subsequent defibrillation attempts for Out-of-hospital cardiac arrest (OHCA) patients with recurrent VF/pVT is uncertain. We investigated the relationship between VF/pVT duration and return of spontaneous circulation (ROSC) in OHCA patients with recurrent shockable rhythms.

METHODS

We analyzed data from the Salt Lake City Fire Department (SLCFD) spanning from 2012 to 2023. The implementation of rhythm-filtering technology since 2011 enabled real-time rhythm interpretation during CPR, with local protocols allowing early defibrillation for recurrent/refractory VF/pVT cases. We included patients experiencing four or five episodes of VF and pVT rhythms and employed generalized estimating equation (GEE) regression analysis to examine the association between VF/pVT durations preceding recurrent defibrillation and return of spontaneous circulation (ROSC).

RESULTS

Analysis of 622 appropriate shocks showed that patients achieving ROSC had significantly shorter median VF/pVT duration than those who did not achieve ROSC (0.83 minutes vs. 1.2 minutes, p = 0.004). Adjusted analysis of those with 4 VF/pVT episodes (N = 142) revealed that longer VF/pVT durations were associated with lower odds of achieving ROSC (odds ratio: 0.81, 95% CI: 0.72-0.93, p = 0.005). Every one-minute delay in intra-arrest defibrillation is predicted to decrease the likelihood of achieving ROSC by 19%.

CONCLUSION

Every one-minute increase in intra-arrest VF/pVT duration was associated with a statistically significant 19% decrease in the chance of achieving ROSC. This highlights the importance of reducing time to shock in managing recurrent VF/pVT. The findings suggest reevaluating the current recommendations of two minutes intervals for rhythm check and shock delivery.

Revisiting the Association Between "Gateway Hypothesis" of Early Drug Use and Drug Use Progression: A Cohort Analysis of Peer Influences on Drug Use Progression Among a Population Cohort

Background and objective: Findings from observational studies indicate that early drug use is a strong predictor of further drug abuse. Because competing explanations abound in cross-sectional studies, causal interpretations from these investigations pose considerable challenge. We evaluated the relationship between early drug use and progression, while estimating modifying influences of adolescents' social contexts. Method: We applied a national longitudinal survey of 11,182 adolescents growing into adulthood over a 14-year period. The data provided a natural setting to evaluate the relationship between early drug use and drug use in three subsequent waves. We applied generalized estimating equation models to analyze these relationships. Results: Evidence showed over a relatively short period (approximately one year) early drug use was an independent predictor of illicit drugs in adolescence but not adulthood. The adjusted odds ratio for using substances in adulthood were marijuana (aOR, 1.33; 95% CI: 1.11-1.60), illicit drugs (aOR, 1.49; 95% CI: 1.04-2.12) and cocaine (aOR, 5.00; 95% CI: 2.75-9.10). Further, drug use was higher among older adolescence living in a neighborhood and reporting drug use as a big problem. In adulthood, neighborhood drug problems appear to have minimal influence on drug use escalation. Conclusion: The current findings call into question the causal interpretation of early drug use among adolescents as determinants of future drug escalation in adulthood. The overall impact of peer relationships on future drug escalation might depend on not only the extent of adolescent closeness to peers but also on continuity of friendship over time and other influencing social contexts.

Differences in continence rates in individuals with spina bifida based on ethnicity

BACKGROUND

Ethnic disparities in continence rates in spina bifida (SB) have been studied regionally but not nationally. National SB Patient Registry (NSBPR) data were analyzed to explore differences in prevalence of bowel and bladder continence and interventions between Hispanics/Latinos and others.

METHODS

Participants 5 to 21 years were categorized into Hispanic/Latino and non-Hispanic/non-Latino. Bladder/bowel continence was defined as dry/no involuntary stool leakage during the day or none/⩽ monthly incontinence. Chi-square test, Wilcoxon Two Sample Test, and generalized estimating equation (GEE) were used for statistical analysis.

RESULTS

Twenty-five percent of the 4,364 patients were Hispanic/Latino. At their most recent clinic visit, Hispanics/Latinos demonstrated lower rates of urinary continence (38.6% vs. 44.9%; p= 0.0003), bowel continence (43.9% vs. 55.8%, p< 0.0001), private insurance (p< 0.0001), bowel (p< 0.0001) or bladder surgeries (p= 0.0054), and more vesicostomies (p= 0.0427) compared to others. In multiple GEE models, Hispanic/Latino participants demonstrated lower odds of bowel continence as compared to non-Hispanic/non-Latino participants (estimated odds ratio, 0.82, 95% CI, 0.72-0.94, p= 0.0032).

CONCLUSIONS

After controlling for covariates, Hispanics/Latinos with SB are less likely to report bowel continence. Clinicians are encouraged to consider the risk of negative health disparities for Hispanic patients with SB and work to mitigate this risk.

Relationship between characteristics of volunteer community health workers and antiretroviral treatment outcomes in a community-based treatment programme in Uganda

Community health workers (CHWs) can help to redress the shortages of health human resources needed to scale up antiretroviral treatment (ART). However, the selection of CHWs could influence the effectiveness of a CHW programme. The purpose of this observational study was to assess whether sociodemographic characteristics and geographic proximity to patients of volunteer CHWs were predictors of clinical outcomes in a community-based ART (CBART) programme in Kabarole, Uganda. Data from CHW surveys for 41 CHWs and clinic charts for 185 patients in the CBART programme were analysed using multivariable logistic and Cox regression models. Time to travel to patients was the only statistically significant characteristic of CHWs associated with ART outcomes. Patients whose CHWs had to travel one or more hours had a 71% lower odds of virologic suppression (adjusted OR = 0.29, 95% CI = 0.13-0.65, p = .002) and a 4.52 times higher mortality hazard rate (adjusted HR = 4.52, 95% CI = 1.20-17.09, p = .026) compared to patients whose CHWs had to travel less than one hour. The findings show that the sociodemographic characteristics of CHWs were not as important as the geographic distance they had to travel to patients.

Effect of provider continuity on test repetition

BACKGROUND

Provider continuity (PC) occurs when a patient is treated by the same physician over time. A perceived benefit of PC is decreased test repetition. Repeat tests make up a significant proportion of overall laboratory utilization. This study determined whether test repetition increases when PC decreases.

METHODS

Cohort study of adults in eastern Ontario, Canada between September 1999 and September 2000 using population-based clinical databases. The primary study outcome was the probability that 7 common laboratory tests (hemoglobin, sodium, creatinine, thyrotropin, total cholesterol, ferritin, and hemoglobin A1C) were repeated at physician visits subsequent to the index test. We determined whether the probability of test repetition changed if the follow-up physician ordered the index test. We adjusted for multiple factors regarding the patient (age, sex, days in hospital, and number of physician visits in previous year), index test (normality and location), follow-up visit (location and time from index test), and follow-up physician (age and specialty).

RESULTS

The study included 881,353 patients, 1,419,438 index laboratory tests, and 7,622,938 follow-up physician visits. After adjusting for other important factors, we found that tests were significantly more likely to be repeated if the follow-up physician ordered the index test (adjusted odds ratio range 2.5-5.9). This association was consistent in most subgroups.

CONCLUSIONS

For these common laboratory investigations, PC was associated with increased, not decreased, test repetition. This suggests that increased PC alone will likely not decrease test utilization.

Effects of volunteering on the well-being of older adults

OBJECTIVES

This study tests the effects of volunteering on the well-being of older adults, including the effect of level of engagement, the moderating effects of demographic and social factors, and the effects of the nature of the volunteer experience.

METHODS

This is a secondary data analysis of three waves of data from the Americans' Changing Lives Study. Self-rated health, functional dependency, and depression are regressed on the well-being measures from the previous waves, other control variables and volunteer status, volunteer hours, type and number of volunteer organizations, and the perceived benefit to others of the volunteer work.

RESULTS

Older adults who volunteer and who engage in more hours of volunteering report higher levels of well-being. This positive effect was not moderated by social integration, race, or gender. There was no effect of the number of organizations for which the older adult volunteered, the type of organization, or the perceived benefit of the work to others.

DISCUSSION

This work contributes to a knowledge base that points to the development of social programs and policies that maximize the engagement of older adults in volunteer roles. The findings suggest that targeting efforts may not be warranted, in that there are not differential benefits according to personal characteristics of the volunteer. Future studies have to address the nature of the social institutions that will maximize the number of elders in these roles and the benefits that they accrue.