Development of an accelerometer-based wearable sensor approach for alcohol consumption detection.

BACKGROUND: Alcohol is a commonly used substance associated with significant public health consequences. Treatment is often stigmatized and limited with regard to both access and affordability, demonstrating the need for innovations in alcohol treatment. Accelerometer sensors can detect drinking without user input and are widely incorporated into wearable devices, increasing accessibility and affordability. METHODS: We compared a distributional and random forest classification approach to detect and evaluate sensor-based drinking data. Data were collected at a local state fair (n = 194), where participants drank water at specified intervals interspersed with confounding behaviors (e.g., touching nose, rubbing forehead, or yawning) while wearing an Android-based smartwatch for 10 min. Participants were randomized to receive one of three drinking container shapes: pint, martini, or wine. RESULTS: The random forest model achieved an overall testing accuracy of 93% (sensitivity = 0.32; specificity = 0.99; positive predictive value = 0.74). The distributional algorithm achieved an overall accuracy of 95% (sensitivity = 0.76; specificity = 0.97; positive predictive value = 0.72). The distributional algorithm had a significantly greater accuracy (t(193) = 7.73, p < 0.001, d = 0.56) and sensitivity (t(193) = 24.5, p < 0.001, d = 1.76). Equivalency testing demonstrated significant equivalency to the ground truth for sip duration (tlower(193) = 16.92, p < 0.001; tupper(193) = -9.85, p < 0.001) and between-sip interval (tlower(193) = 1.72, p = 0.044; thigher(193) = -3.96, p < 0.001). However, the random forest did not have significant equivalency to the ground truth for between-sip interval (tlower(193) = 1.98, p = 0.025; thigher(193) = 0.160, p = 0.564). CONCLUSIONS: Overall, the results indicated that consumer-grade smartwatches can be utilized to detect and measure alcohol use behavior using machine learning and distributional algorithms. This work provides the methodological foundation for future research to analyze the behavioral pharmacology of alcohol use and develop accessible just-in-time clinical interventions.

Determinants of perceived pain relief from acute alcohol intake in a laboratory setting.

Background: Studies of alcohol analgesia often assume that changes in pain sensitivity reflect the negative reinforcing effects of alcohol in pain self-management. However, factors that may influence perceived pain relief due to alcohol use remain incompletely characterized. Thus, the primary aim of this study was to identify which factors are most strongly related to self-reported pain relief in individuals with and without chronic pain after alcohol consumption. Methods: This study combined data from two studies of alcohol analgesia in individuals who regularly consume alcohol with and without chronic pain. Alcohol analgesia expectancies were assessed during screening. In laboratory sessions, participants received an alcohol-containing (.08 g/dL target BrAC) or placebo beverage and rated subjective intoxication and subjective response (positive/negative aspects of stimulation/sedation). Participants underwent quantitative sensory testing to measure pain intensity, pain threshold, and relief. Paired sample t-tests determined effects of alcohol on pain measures. Hierarchical linear models determined factors associated with pain relief ratings in the alcohol condition. Results: Pain relief and pain threshold were higher in the alcohol session relative to placebo, but pain intensity did not differ. In a 4-step hierarchical linear model, expectancy of pain relief, subjective intoxication, and high positive affect, but not pain threshold or pain intensity, were significantly and uniquely associated with perceived relief. Conclusions: Taken together, results suggest the negative-reinforcing effects of alcohol for pain-management are not completely reflected by changes in pain sensitivity in a laboratory setting. Expectancies and subjective response may be important in determining an individual's evaluation of alcohol's efficacy for pain self-management.

Divergent association between pain intensity and resting-state fMRI-based brain entropy in different age groups.

Pain is a multidimensional subjective experience sustained by multiple brain regions involved in different aspects of pain experience. We used brain entropy (BEN) estimated from resting-state fMRI (rsfMRI) data to investigate the neural correlates of pain experience. BEN was estimated from rs-fMRI data provided by two datasets with different age range: the Human Connectome Project-Young Adult (HCP-YA) and the Human Connectome project-Aging (HCP-A) datasets. Retrospective assessment of experienced pain intensity was retrieved from both datasets. No main effect of pain intensity was observed. The interaction between pain and age, however, was related to increased BEN in several pain-related brain regions, reflecting greater variability of spontaneous brain activity. Dividing the sample into a young adult group (YG) and a middle age-aging group (MAG) resulted in two divergent patterns of pain-BEN association: In the YG, pain intensity was related to reduced BEN in brain regions involved in the sensory processing of pain; in the MAG, pain was associated with increased BEN in areas related to both sensory and cognitive aspects of pain experience.

Associations between smoking and pain in early recovery in residential substance use treatment-seekers.

INTRODUCTION: A growing literature indicates bidirectional associations between pain and tobacco use. Cigarette smokers are at increased risk for chronic pain, and observational and experimental studies indicate that pain increases motivation to smoke. Tobacco use disorder frequently co-occurs with other substance use disorders, which are also associated with chronic pain vulnerability. Despite evidence that pain significantly predicts smoking and relapse, associations between smoking history/trajectory and changes in pain over the course of treatment have not been characterized. The objective of the study was to determine the association between in-treatment smoking trajectory, pack-years (i.e., number of cigarette packs smoked per day multiplied by smoking duration), pain-related interference in daily activities, and pain intensity over the course of residential treatment. METHODS: In this study, 280 adult smokers in a residential SUD treatment center in North Central Florida completed questionnaires assessing cigarette use, pain intensity, and pain interference at treatment entry and discharge (Mean = 80.3 days, SD = 25.6). Most participants were diagnosed with alcohol use disorder (66.1 %). Opioid (27.9 %) and cannabis use disorders (29.6 %) were also common. Participants were grouped by whether their smoking increased (n = 36), decreased (n = 46), or stayed the same (n = 133) from entry to discharge. RESULTS: Analyses indicated a positive association between pack-years and pain intensity at both baseline (r = 0.185, p = 0.018) and discharge (r = 0.184, p = 0.019). Smoking trajectory was associated with pack-years, with those decreasing smoking having greater pack-years than those sustaining or increasing use [F(2,136) = 8.62, p < 0.01, η2p = 0.114]. Mixed general linear models indicated pain intensity [F(1,274) = 44.15, p < 0.0001, η2p = 0.138] and interference in day-to-day activities [F(1,276) = 31.79, p < 0.0001, η2p = 0.103] decreased significantly over time. However, there was no main effect of smoking trajectory on pain intensity [F(2,212) = 2.051, p = 0.131, η2p = 0.019] or of smoking trajectory by time interaction [F(2, 212) = 1.228, p = 0.295, η2p = 0.011]. CONCLUSIONS: Overall, findings provide evidence that smoking behavior influences pain within the context of residential substance use treatment. Given that pain is associated with urge to use substances and risk of return to use, more consistent and rigorous assessment of pain and proactive pain management is likely to enhance substance use treatment outcomes among people who smoke.

Use and co-use of alcohol and cannabis following physical pain in the daily life of community adults engaged in regular substance use.

OBJECTIVE: Alcohol and cannabis are often perceived as pain-relieving. However, minimal work has examined whether people use and co-use these substances following pain in daily life. METHOD: Forty-six adults reporting weekly use of alcohol and/or cannabis completed a 60-day ecological momentary assessment protocol, answering at least four daily reports on their alcohol and cannabis use and pain (nassessments = 10,769 over 2,656 days). We examined whether self-reported pain so far that day (cumulative-average pain) was associated with subsequent alcohol and cannabis use and same-occasion co-use. Models also addressed whether associations differed for initiating versus continuing a use episode. Hypotheses were preregistered. RESULTS: A multinomial multilevel model found that cumulative-average pain was associated with a greater likelihood of same-occasion co-use in the continuation phase but not the initiation phase, compared to no use (OR = 1.48,95% CI [1.06, 2.06], p = .023) and alcohol use (OR = 1.52, CI [1.03, 2.26], p = .037). Cumulative-average pain was largely not associated with alcohol-only and cannabis-only use. After alcohol use, greater pain was associated with cannabis use (OR = 1.37, CI [1.11, 1.70], p = .004), but not the reverse. Secondary analyses found greater previous-occasion (not cumulative) pain was associated with initiation of alcohol use and number of drinks, and initiation and continuation of cannabis use, but not number of cannabis hits. CONCLUSIONS: Although not all hypotheses were supported, pain was associated with subsequent substance use in this sample engaged in regular substance use and not recruited for chronic pain. Cumulative pain may be particularly related to alcohol-cannabis same-occasion co-use, which may increase the risk of substance use-related problems over time. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

A Brief Screening Tool for Risk of Self-Medication of Pain With Substance Use.

OBJECTIVES: Substance use and pain are both growing public health concerns globally. Evidence suggests that individuals may use substances in order to self-medicate their pain. The Catastrophizing, Anxiety, Negative Urgency, and Expectancy model was developed to provide a theoretical foundation for the modifiable risk factors implicated in self-medication of pain with substance use. This study aimed to use the outcomes in the Catastrophizing, Anxiety, Negative Urgency, and Expectancy model to develop a brief clinical screening tool to identify individuals at risk for self-medication. METHODS: Participants (N = 520; M age = 38.8) were adults who endorsed the past three-month use of at least one substance and completed an online questionnaire. Logistic regression and receiver operator characteristic analyses were used to reduce the initial 104-item questionnaire to the items needed to achieve a minimum accuracy score of 0.95 and 0.90. RESULTS: A 14-item and a 7-item questionnaire were derived from the initial larger questionnaire. Both of these questionnaires were significantly correlated with the outcome variables and were significantly associated with health risk and percent of use because of pain. The R2 values between the 14- and 7-item versions were only significantly different for the percent of alcohol use because of pain. CONCLUSIONS: The study provides two brief screening tools to screen for individuals at risk for self-medication of pain with substance use that can be easily implemented within clinical settings. Further, the screening tools provide insight into modifiable risk factors for self-medication and may also be valuable to monitor treatment response.

Pain Predicts Dropout From Substance Use Treatment.

OBJECTIVE: This project aimed to characterize the relationship between physical pain experienced at time of entry to residential treatment for substance use disorders (SUDs) and the frequency of treatment dropout. We hypothesized that both endorsement of recent pain and higher magnitude of endorsed pain intensity would be associated with higher dropout rates. We further hypothesized that these effects would be exacerbated among patients with opioid use disorder (OUD). METHOD: Participants included 1,095 individuals in residential treatment for SUD. Data were collected within 24 hours of treatment entry. Analyses were conducted using logistic regression with dropout as the dependent variable. Dropout was operationally defined as leaving treatment against medical advice or being discharged from treatment because of use of substances. Pain (including endorsement and intensity) was the primary independent variable in all analyses. Analyses included demographic and affective covariates and included both main effects of OUD and interaction terms between OUD and pain. RESULTS: Pain endorsement was associated with greater frequency of dropout (odds ratio [OR] = 1.49, p = .04). Higher levels of pain intensity predicted increased rates of dropout (OR = 1.13, p < .01). In contrast with our hypothesis, no interactions between OUD and pain were observed. CONCLUSIONS: These results underscore the import of integrating pain monitoring and pain interventions as core components of treatment for SUD. Our findings are highly consistent with a growing literature recognizing the impact of pain across a constellation of important treatment outcomes and provide novel data strongly suggesting that pain predicts early cessation of treatment.

Expectancy of alcohol analgesia moderates perception of pain relief following acute alcohol intake.

Although laboratory studies indicate alcohol reduces pain intensity and increases pain threshold, these effects likely do not completely explain perceived pain relief from alcohol intake. In this study, we tested expectancy of alcohol analgesia (EAA) as a moderator of subjective pain relief following oral alcohol challenge in individuals with and without chronic orofacial pain. Social drinkers (N = 48; 19 chronic pain; 29 pain-free controls) completed two testing sessions: alcohol administration (BrAC: 0.08 g/dL) and placebo. Alcohol expectancy (AE) was assessed using the EAA questionnaire and two 100-mm Visual Analogue Scales (VASs) regarding strength of belief that alcohol provides pain relief (AE VAS 1) or reduces pain sensitivity (AE VAS 2). Participants completed quantitative sensory testing (QST) involving application of pressure to the masseter insertion. Pain threshold (lbf; three repetitions) and pain intensity (4, 5, and 6 lbf; three repetitions each; 100-mm VAS) were collected. After each stimulus, participants rated perceived pain relief due to consumption of the study beverage (0-100 VAS). Higher EAA and AE VAS 1 ratings were associated with stronger perceived relief in the alcohol, but not placebo, condition. However, expectancy specifically related to reduction in pain sensitivity (AE VAS 2) was not associated with relief. Additionally, changes in pain threshold and intensity were not significantly correlated with perceived relief. Taken together, results suggest expectancy that alcohol provides pain relief is an important determinant of its negative reinforcing effects. Future studies should investigate challenging these expectancies as a means of reducing alcohol-related risk in people with pain. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Effect of typical alcohol use and expectancies on the social manipulation of drinking behavior in a virtual bar pilot study.

BACKGROUND: Recent work indicates that increasing the drinking rate of a virtual bar-goer (VB) increases the rate of drinking for participants in a virtual reality (VR) bar environment. Here, we test the hypothesis that biopsychosocial factors including typical drinking pattern and expectancy that alcohol enhances social interactions would moderate this effect. METHODS: We assessed the drinking topography (DT) of participants (N=20) in a VR environment with a programmable VB during two testing sessions: one with a fast-drinking VB (30-60s sip interval) and one in which the VB drank slowly (60-120s sip interval). In this secondary analysis, linear mixed models were used to characterize potential interactions of typical daily alcohol intake (quantity-frequency index [QFI]), maximal alcohol consumed in one bout over the past six months (maxQ), Alcohol Use Disorder Identification Test (AUDIT) score, and expectancy that alcohol enhances social and physical pleasures (SPP) with time in simulation and condition on sip interval and volume. RESULTS: Individuals with higher MaxQ showed a reduced effect of time on sip volume such that more intense recent binge episodes were associated with consistent drinking. Greater AUDIT scores were associated with lower sip intervals. In addition, greater SPP expectancy was associated with higher sip volumes, but only in the fast-drinking VB condition. CONCLUSIONS: Greater drinking behavior and social expectancies were associated with more rapid drinking topography. In addition, findings suggest challenging alcohol outcome expectancies related to social enhancement could reduce alcohol-related risks by slowing the rate of alcohol intake in social situations.

Task-dependent functional connectivity of pain is associated with the magnitude of placebo analgesia in pain-free individuals.

BACKGROUND: Task-based functional connectivity (FC) of pain-related regions resulting from expectancy-based placebo induction has yet to be examined, limiting our understanding of regions and networks associated with placebo analgesia. METHODS: Fifty-five healthy pain-free adults over 18 (M = 22.8 years, SD = 7.75) were recruited (65.5% women; 63.6% non-Hispanic/Latino/a/x; 58.2% White). Participants completed a baseline followed by a placebo session involving the topical application of an inactive cream in the context of an expectancy-enhancing instruction set. Noxious heat stimuli were applied to the thenar eminence of the right palm using an fMRI-safe thermode. Stimulus intensity was individually calibrated to produce pain ratings of approximately 40 on a 100-point visual analogue scale. RESULTS: A total of 67.3% of the participants showed a reduction in pain intensity in the placebo condition with an average reduction in pain across the whole sample of 12.7%. Expected pain intensity was associated with reported pain intensity in the placebo session (b = 0.32, p = 0.004, R2 = 0.15). Voxel-wise analyses indicated seven clusters with significant activation during noxious heat stimulation at baseline (pFDR < 0.05). Generalized psychophysiological interaction analysis suggested that placebo-related FC changes between middle frontal gyrus-superior parietal lobule during noxious stimulation were significantly associated with the magnitude of pain reduction (pFDR < 0.05). CONCLUSIONS: Results suggest that stronger expectancy-based placebo responses might be underpinned by greater FC among attentional and somatosensory regions. SIGNIFICANCE: This article provides support and insight for task-dependent functional connectivity differences related to the magnitude of placebo analgesia. Our findings provide key support that the magnitude of expectation-based placebo response depends on the coupling of regions associated with somatosensory and attentional processing.

Association of cerebellar and pre-motor cortex gray matter density with subjective intoxication and subjective response following acute alcohol intake.

Acute alcohol intake produces subjective intoxication (SI) and response (SR; e.g., valanced stimulation and sedation), which has important implications for alcohol-related risk. Individuals who experience less SI may be more likely to engage in risky behaviors while drinking. Gray matter morphometry in brain regions underlying cognitive and affective processes may help to inform individual differences in subjective intoxication and response. The subjective effects of alcohol vary between limbs of the blood alcohol concentration (BAC) curve (i.e., whether BAC is rising or falling; acute tolerance). We examined the relationship between gray matter density (GMD) and SI/SR as a function of BAC limb. Healthy social drinkers (N = 89; 55 women) completed an alcohol challenge paradigm (target BAC = 0.08 g/dL) and structural magnetic resonance imaging (MRI). Participants completed measures of SR and SI on ascending and descending BAC limbs. Association between GMD and SI/SR on each limb were assessed using whole-brain, voxel-wise general linear models. GMD estimates were extracted from significant clusters. Differences in association of GMD and SI/SR between limbs were assessed using hierarchical regression. Significant associations of SI with GMD on the ascending limb were observed in the cerebellum. A significant association between SR and GMD on the descending limb were observed in the pre-motor cortex (BA6) and cerebellum. We identified common and unique associations among cerebellum and pre-central gyrus structures with SI and SR between BAC limbs. Functional imaging studies may further clarify unique dimensions of subjective alcohol effects linked to the observed structural associations.

Association of therapeutic and recreational reasons for alcohol use with alcohol demand.

Motives for alcohol use and behavioral economic measures of demand are associated with alcohol consumption and alcohol-related problems. However, it is unclear how differences in reasons for alcohol use may affect alcohol demand. Additionally, although alcohol is commonly used to self-manage conditions such as pain and sleep problems, the impact of these reasons for alcohol use on alcohol demand is not well characterized. The present study addressed this gap. Participants were adults recruited via Amazon Mechanical Turk as part of a larger study investigating health behaviors. Analyses included participants who reported alcohol use in the past year (N = 637). Participants were categorized as having recreational, therapeutic, or both recreational and therapeutic reasons for using alcohol. A brief, three-item measure of alcohol demand was administered. Multivariate analysis of variance (MANOVA) analyses revealed that alcohol drinkers endorsing both recreational and therapeutic reasons for use had significantly higher average intensity, Omax, and breakpoint indices compared to those who only reported recreational or therapeutic drinking motives (ps < .05; Cohen's d = .09-.17). Secondary analyses revealed differences in demand according to therapeutic reason for alcohol use endorsed. Significant main effects were found for use to relieve pain and anxiety/depression/stress, while interactive effects were detected for use to relieve pain and improve sleep and use to relieve pain and anxiety/depression/stress. Overall, results suggest that alcohol demand is highest in drinkers who consume alcohol for both therapeutic and recreational reasons. This group may be at elevated risk for alcohol use disorder and alcohol-related consequences. Continued research is necessary to examine this possibility. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Pain and alcohol consumption in virtual reality.

Research suggests situational pain may motivate alcohol consumption, suggesting that pain may be an antecedent for problematic drinking behavior. In this pilot project, we assessed the effect of a painful thermal stimulus on drinking topography in a virtual reality bar environment using real alcohol-containing beverages. We also examined psychosocial factors that may account for individual differences in pain as an antecedent for alcohol use. Participants (N = 20, Mage = 25.65 years, 55% female, 15% Hispanic/Latino/a/x) completed a psychosocial screening battery before completing two counterbalanced alcohol self-administration sessions. In each, participants experienced either painful heat (44 °C) or nonnoxious warmth (38 °C). Sip interval (s) and sip volume (g) were measured. Effects of pain on drinking topography were assessed using multilevel models. Multilevel models assessed associations of pain-related changes in topography with hypothesized vulnerability factors. Analyses indicated a significant interaction of pain condition and sex on sip interval (b = -.16.96, p = .015, 95% CI [-30.75, -2.97]), such that painful heat significantly decreased sip interval in men (b = 16.38) but not women (b = -.45). No effect of pain on sip volume was detected (p > .49). Exploratory analyses indicated significant interactions such that the effect of the painful heat condition was stronger in individuals with higher levels of greater negative urgency but the opposite effect for pain catastrophizing. Results suggest acute pain has sex-contingent effects on drinking topography, such that men drank more rapidly while experiencing painful heat. Furthermore, analyses indicated that individuals with greater negative urgency, regardless of sex, may be at elevated risk for hazardous alcohol use when experiencing pain. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Reliability of an adaptive marijuana purchase task.

Purchase tasks are used to measure the value, or demand, for various substances by assessing the amount of a substance individuals would purchase across a series of escalating prices. Marijuana purchase task (MPT) has been previously developed; however, cannabis can be consumed in various forms and measurements, thus raising questions about the applicability of the MPT across cannabis users. An adaptive MPT was developed to allow participants to select their preferred product (e.g., herbal, dabs) and division (e.g., hits, grams). Little research has been done to assess the temporal stability of these measures. Participants (N = 50, Mage = 35.3) who reported at least monthly cannabis use were recruited via Amazon's Mechanical Turk and completed a baseline and repeated original and adaptive MPT. Seventy-two percent (N = 36) of the sample reported the same preferred product and division. Results indicated that the baseline and repeated original MPT were significantly correlated across all indices (rrange = .37-.73), while the baseline and repeated adaptive MPT was significantly correlated with Pmax (r = .31, p = .029) and Omax (r = .57, p < .001). Permutation testing comparing the difference between the original and adaptive MPT on all indices demonstrated a difference for break point (rdifference = .52, p = .004) and elasticity (rdifference = .94, p = .005). Correlations were lower between participants who switched their preferences on the adaptive MPT. Only elasticity was significantly different (rdifference = .93, p = .012) between tasks among participants who did not switch their preferences. Results provide support that both the original and adaptive MPT are reliable across repeated measurement and demonstrate the importance of assessing cannabis product and division preferences. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Neural and Psychosocial Mechanisms Underlying Alcohol Use and Pain Interactions: Overview of Current Evidence and Future Directions.

Purpose of Review: A growing body of research indicates bidirectional associations between alcohol use and pain. In this review, we highlight common neural and psychosocial mechanisms underlying pain and alcohol use and identify current gaps in the literature regarding alcohol/pain interactions. We also suggest future directions for the field moving forward, including more nuanced conceptualization of alcohol's negative reinforcing effects in the context of pain, broader use of clinically-relevant experimental pain induction modalities, and characterization of age, biological sex, gender, race, and ethnicity as moderators of pain/alcohol interactions. Recent Findings: Acute alcohol intake has analgesic and negative-reinforcing effects in the context of pain, and chronic heavy alcohol use appears to increase risk for development of chronic pain. At the same time, pain, both acute and chronic, acts as a proximal antecedent for alcohol use and is associated with relapse risk for individuals in recovery from alcohol use disorder. Summary: Although the links between alcohol use and pain are increasingly appreciated, significant gaps in understanding remain and systematic study of alcohol/pain interactions at all levels, including basic, preclinical, translational, and interventional, is needed.

Longitudinal associations between pain and substance use disorder treatment outcomes.

INTRODUCTION: Pain is commonly reported among those in treatment for substance use disorders (SUD) and is associated with poorer SUD treatment outcomes. The current study examined the trajectory of pain over the course of SUD treatment and associations with substance use outcomes. METHODS: This observational study included adults seeking treatment for alcohol, cannabis, or opioid use disorders (N = 811). Participants completed a battery of assessments at treatment admission, 30 days post admission, and at discharge, including measures of demographics, pain, quality of life, abstinence self-efficacy, and craving. RESULTS: Analyses indicated linear reductions in pain intensity and interference over time. Significant interactive effects were observed for opioid use disorder (OUD) and time, such that participants with OUD had greater reductions in pain intensity and interference over time compared to those without OUD. Elevated pain intensity was associated with negative treatment outcomes, including reduced quality of life and abstinence self-efficacy, and greater craving and negative affect. CONCLUSIONS: Reductions in pain occur over the course of SUD treatment, particularly for those with OUD. Greater pain was also associated with adverse SUD treatment outcomes. Results suggest that treatment and associated abstinence may be beneficial for those with co-occurring pain and SUD, highlighting an additional benefit of improving access to SUD treatment for patients and health care systems. Future research should replicate these findings among diverse samples and further characterize the trajectory of pain during and after SUD treatment.

Analgesic effects of alcohol in adults with chronic jaw pain.

BACKGROUND: Although recent literature provides promising support for the analgesic properties of alcohol, potential differences in alcohol analgesia as a function of chronic pain status are not well understood. Thus, this study examined chronic pain status as a potential moderator of alcohol analgesia and distinguished between multiple aspects of pain experience and sensitivity: pain threshold, pain intensity, pain unpleasantness, and perceived relief. METHODS: Social drinkers with (N = 19) and without (N = 29) chronic jaw pain completed two testing sessions in a counterbalanced order: alcohol (target BrAC = 0.08 g/dl) and placebo. In each, pressure algometry was performed at the insertion of the masseter. Alcohol analgesia was assessed by examining the main and interactive effects of beverage condition, pressure level (4, 5, or 6 pound-feet [lbf]), and chronic jaw pain status (chronic pain vs. pain-free control) on quantitative sensory testing measures and pain relief ratings following noxious stimuli. RESULTS: Analyses indicated significant increases in pain threshold and pain relief and reductions in pain unpleasantness and pain intensity, under the alcohol condition. Chronic pain participants demonstrated lower pain thresholds and greater pain intensity and pain unpleasantness ratings than controls. There were no interactive effects of alcohol and pain conditions on any pain measure. CONCLUSIONS: Findings provide experimental evidence of alcohol's analgesic and pain-relieving effects and suggest that these effects do not significantly differ by chronic pain status. Individuals, who self-medicate pain via alcohol consumption, irrespective of pain status, may be at increased risk to engage in hazardous drinking patterns and thus experience adverse alcohol-related consequences.

Stress Mediates the Association Between Pain and Alcohol Use in College Students.

Background: Alcohol use in young adults is highly prevalent and associated with numerous consequences, including academic difficulties and motor vehicle accidents. Pain is one factor that has been increasingly shown to be associated with higher rates of alcohol consumption and riskier patterns of drinking among undergraduate students. Although pain has traditionally been viewed as a lesser concern for young adults, current research demonstrates that pain may be more prevalent in younger populations than originally thought. However, little is known about how common psychosocial factors, such as stress and subjective social status (SSS), influence the association between pain and alcohol consumption in college students. Objective: The study's goal was to examine the effect of stress and SSS on the relationship between pain and alcohol consumption. Participants and Methods: Participants (N = 445, 39.3% women, Mage = 22.98) were 18- to 25-year-old college students who completed an online questionnaire. Results: Pain was significantly associated with total weekly alcohol consumption (r(445) = .22, p < 0.001); this association was significantly mediated by stress (b = 0.15, SE = 0.04, 95% CI = [.07,0.23]). SSS was significantly positively associated with alcohol consumption (r(445) = .22, p < 0.001) but was not found to significantly moderate the relationship between stress and alcohol use. Conclusion: Results suggest that efforts to reduce college student alcohol use should include assessment of pain and stress given their association with alcohol consumption. Further, findings suggest that future studies are warranted to prospectively examine pain as an antecedent for alcohol use and to examine the utility of incorporating stress management techniques in pain-focused interventions to indirectly target alcohol use.

A virtual reality platform for the measurement of drinking topography.

BACKGROUND: The assessment of alcohol consumption during a drinking bout, known as drinking topography, may help improve understanding of biopsychosocial mechanisms underlying alcohol consumption. However, past studies have been limited by effort-intensive, time-consuming, and error-prone processes involved in collecting, organizing, and standardizing drinking topography data. Recent technologies allowing integrated data collection and greater environmental control, such as virtual reality (VR), could resolve these problems. METHODS: In this pilot project, we assessed alcohol consumption topography of participants in a VR drinking environment with a programmable virtual confederate (i.e., bar goer) during two testing sessions. In one, the confederate drank quickly (30-60 s sip interval). In the other, the confederate drank slowly (60-120 s sip interval). Participants' hands and beverage were represented in VR. Between sips, beverages were placed on a Bluetooth-enabled scale, allowing real-time updates of drink weight. Participant experience was assessed after each testing visit. Multilevel modeling was used to characterize the effect of confederation condition on sip interval and sip volume. Descriptive analyses were used for participant experience data. RESULTS: Results showed significant, moderate-to-strong between-visit correlations for topographic measures (r = 0.50 to r = 0.84) and indicate participants found the experience to be comfortable and acceptable. Multilevel models indicated participants had greater sip volumes and lower sip intervals when the confederate drank quickly. CONCLUSIONS: Future studies should take advantage of the considerable translational value of this technology to improve understanding of risk associated with individual drinking bouts and develop novel interventions for reducing hazardous drinking.