Propensity Score-matched Regression Models Research Articles

Abstract 10333: Recreational Multi Use Trails and Cardiovascular Disease: A Difference-in-Differences 18 Year Natural Experiment

Introduction: There is little experimental evidence of the impact of multi-use recreational trails that support physical activity on cardiovascular disease (CVD). Hypothesis: Neighbourhoods that added multi-use trails would experience a greater decline in CVD events and risk factors compared to neighbourhoods that did not. Methods: We used a difference in differences design to study the addition of four multi-use trails 4-7km in length on CVD-related outcomes using administrative health, census and built environment data available for all citizens 30 years of age and older from Winnipeg, Canada. A 400m buffer stratified intervention and comparison neighbourhoods. Bicycle counts were recorded via electromagnetic counters for 5 years on all trails. The primary and secondary outcomes were composite measures of incident CVD events (mortality, ischemic heart disease, cerebrovascular disease and congestive heart failure) and CVD risk factors (hypertension, diabetes and dyslipidemia) and assessed quarterly for 10 years prior to and 6 years following the intervention. Intervention and comparison areas were propensity score matched, using scores regressed from baseline measures of age, sex, socioeconomic indicators, and built environment attributes that support physical activity. Results: Between 2012 and 2018, 1,429,588 cyclists were recorded on the trails and cycling use varied ~2.0-fold across the trails. Between 2000 and 2018, there were 82,632 CVD events and 201,058 CVD risk events. During the 18-year natural experiment CVD event rates and risk factors declined ~33% in both comparison and intervention neighbourhoods. In propensity score matched regression models, the incident rate ratio was 1.06 (95% CI: 0.90 to 1.24) for CVD events and 0.92 (95% CI: 0.84 to 1.02) for CVD risk factors. Sensitivity analyses revealed greater effect sizes with increasing trail use (incident rate ratios for highest vs lowest cycling counts = 0.85; 95% CI: 0.75 to 0.96 vs 1.08; 95% CI: 0.92 to 1.27). Conclusions: The addition of recreational multi-use trails was not associated with changes in overall CVD events or risk factors in adjacent neighbourhoods, compared to distant neighbourhoods, however, the effects on CVD risk factors may be influenced by trail use.

Do Acetylcholinesterase Inhibitors Prevent or Delay Psychotropic Prescribing in People With Dementia? Analyses of the Swedish Dementia Registry

ObjectivesTo investigate whether acetylcholinesterase inhibitor (AChEI) use prevents or delays subsequent initiation of psychotropic medications in people with Alzheimer's disease (AD) and Lewy body dementia (LBD). MethodsCohort study of 17,763 people with AD and LBD, without prior psychotropic use at time of dementia diagnosis, registered in the Swedish Dementia Registry from 2007 to 2015. Propensity score-matched regression models were used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between time-dependent AChEI use and risk of psychotropic initiation. ResultsCompared with matched comparators, AChEI users had a lower risk of antipsychotic (HR: 0.85, 95%CI: 0.75–0.95) and anxiolytic (HR: 0.76, 95%CI: 0.72–0.80) initiation. In subanalyses, this association remained significant at higher AChEI doses, and in AD but not LBD. There were no associations between AChEI use and initiation of antidepressants or hypnotics. ConclusionAChEI use may be associated with lower risk of antipsychotic and anxiolytic initiation in AD, particularly at higher doses. Further investigation into aceytylcholinesterase inhibitors in behavioral and psychological symptoms of dementia management in LBD is warranted.

Norepinephrine and Vasopressin Compared With Norepinephrine and Epinephrine in Adults With Septic Shock.

Background: The optimal adjuvant vasopressor to norepinephrine in septic shock remains controversial. Objective: To compare durations of shock-free survival between adjuvant vasopressin and epinephrine. Methods: A retrospective, single-center, matched cohort study of adults with septic shock refractory to norepinephrine was conducted. Patients receiving norepinephrine not at target mean arterial pressure (MAP; 65 mm Hg) were initiated on vasopressin or epinephrine to raise MAP to target. Vasopressin-exposed patients were matched to epinephrine-exposed patients using propensity scores. Mortality outcomes were examined using multivariable Poisson regression with robust variance estimation. Results: Of 166 patients, 96 (entire cohort) were included in the propensity score-matched cohort. Shock-free survival durations in the first 7 days were similar between epinephrine- and vasopressin-exposed patients in the matched cohort (median = 13.2 hours, interquartile range [IQR] = 0-121.0, vs median = 41.3 hours, IQR = 0-125.9; P = 0.51). Seven- and 28-day mortality rates were similar in the matched cohort (7-day: 47.9% vs 39.6%, P = 0.35; 28-day: 56.3% vs 58.3%, P = 0.84). Mortality rates were similar between epinephrine- and vasopressin-exposed patients in propensity score-matched regression models with and without adjustments at 7 (relative risk [RR] = 1.28, 95% CI = 0.92-1.79; RR = 1.21, 95% CI = 0.81-1.81) and 28 days (RR = 1.04, 95% CI = 0.81-1.34; RR = 0.96, 95% CI = 0.69-1.34). Conclusion and Relevance: Shock-free survival durations were similar in matched epinephrine- and vasopressin-exposed groups. Adjuvant epinephrine or vasopressin alongside norepinephrine to raise MAP to target requires further investigation.