Applying Farr’s Law to project the drug overdose mortality epidemic in the United States

Unintentional drug overdose has increased markedly in the past two decades and surpassed motor vehicle crashes as the leading cause of injury mortality in many states. The purpose of this study was to understand the trajectory of the drug overdose epidemic in the United States by applying Farr’s Law. Farr’s “law of epidemics” and the Bregman-Langmuir back calculation method were applied to United States drug overdose mortality data for the years 1980 through 2011 to project the annual death rates from drug overdose from 2012 through 2035. From 1980–2011, annual drug overdose mortality increased from 2.7 to 13.2 deaths per 100,000 population. The projected drug overdose mortality would peak in 2016–2017 at 16.1 deaths per 100,000 population and then decline progressively until reaching 1.9 deaths per 100,000 population in 2035. The projected data based on Farr’s Law suggests that drug overdose mortality in the United States will decline in the coming years and return to the 1980 baseline level approximately by the year 2034

Community Health Worker Interventions to Improve Glycemic Control in People with Diabetes: A Systematic Review and Meta-Analysis

OBJECTIVES: We set out to review the efficacy of Community Health Worker (CHW) interventions to improve glycemia in people with diabetes. METHODS: Data sources included the Cochrane Central Register of Controlled Trials, Medline, clinicaltrials.gov, Google Scholar, and reference lists of previous publications. We reviewed randomized controlled trials (RCTs) that assessed the efficacy of CHW interventions, as compared to usual care, to lower hemoglobin A1c (A1c). Two investigators independently reviewed the RCTs and assessed their quality. Only RCTs with a follow-up of at least 12 months were meta-analyzed. A random effects model was used to estimate, from unadjusted within-group mean reductions, the standardized mean difference (SMD) in A1c achieved by the CHW intervention, beyond usual care. RESULTS: Thirteen RCTs were included in the narrative review, and nine of them, which had at least 12 months of follow-up, were included in the meta-analysis. Publication bias could not be ruled-out due to the small number of trials. Outcome heterogeneity was moderate (I(2)= 37 %). The SMD in A1c (95 % confidence interval) was 0.21 (0.11-0.32). Meta-regression showed an association between higher baseline A1c and a larger effect size. CONCLUSIONS: CHW interventions showed a modest reduction in A1c compared to usual care. A1c reduction was larger in studies with higher mean baseline A1c. Caution is warranted, given the small number of studies