Using socially-sensed data to infer ZIP level characteristics for the spatiotemporal analysis of drug-related health problems in Maryland.

This research investigated how socially sensed data can be used to detect ZIP level characteristics that are associated with spatial and temporal patterns of Emergency Department patients with a chief complaint and/or diagnosis of overdose or drug-related health problems for four hospitals in Baltimore and Anne Arundel County, MD during 2016-2018. Dynamic characteristics were identified using socially-sensed data (i.e., geo-tagged Twitter data) at ZIP code level over varying temporal resolutions. Data about three place-based variables including comments and concerns about crime, drug use, and negative or depressed sentiments, were extracted from tweets, along with data from four socio-environmental variables from the American Community Survey were collected to explore socio-environmental characteristics during the same period. Our study showed a statistically significant increase in adjusted rates of Emergency Department (ED) visits occurred between June and November 2017 for patients residing in ZIP codes in western Baltimore and northeastern Anne Arundel County. During this period, the three topics extracted from Twitter data were highly correlated with the ZIP codes where the patients were residing. Exploring the dynamic spatial associations between socio-environmental variables and ED visits for acute overdose assists local health officials in optimizing interventions for vulnerable locations.

Choice between delayed food and immediate oxycodone in rats.

RATIONALE: The choice to seek immediate drug effects instead of more meaningful but delayed rewards is a defining feature of addiction. OBJECTIVES: To develop a rodent model of this behavior, we allowed rats to choose between immediate intravenous delivery of the prescription opioid oxycodone (50 µg/kg) and delayed delivery of palatable food pellets. RESULTS: Rats preferred food at delays up to 30 s, but they chose oxycodone and food equally at 60-s delay and preferred oxycodone over food at 120-s delay. Comparison of food-drug choice, food-only, and drug-only conditions indicated that food availability decreased drug intake, but drug availability increased food intake. In the food-only condition, food was effective as a reinforcer even when delayed by 120 s. Pre-session feeding with chow slowed acquisition of food and drug self-administration, but did not affect choice. To establish procedures for testing potential anti-addiction medications, noncontingent pre-treatment with oxycodone or naltrexone (analogous to substitution and antagonist therapies, respectively) were tested on a baseline in which oxycodone was preferred over delayed food. Naltrexone pre-treatment decreased drug intake and increased food intake. Oxycodone pre-treatment decreased drug intake, but also produced extended periods with no food or drug responding. CONCLUSIONS: These findings show that the contingencies that induce preference for drugs over more meaningful but less immediate rewards in humans can be modeled in rodents, and they suggest that the model could be useful for assessing the therapeutic potential of treatments and exploring the underlying behavioral and neural mechanisms involved in addiction.