Brain Imaging Biomarkers for Chronic Pain

The prevalence of chronic pain has reached epidemic levels. In addition to personal suffering chronic pain is associated with psychiatric and medical co-morbidities, notably substance misuse, and a huge a societal cost amounting to hundreds of billions of dollars annually in medical cost, lost wages, and productivity. Chronic pain does not have a cure or quantitative diagnostic or prognostic tools. In this manuscript we provide evidence that this situation is about to change. We first start by summarizing our current understanding of the role of the brain in the pathogenesis of chronic pain. We particularly focus on the concept of learning in the emergence of chronic pain, and the implication of the limbic brain circuitry and dopaminergic signaling, which underly emotional learning and decision making, in this process. Next, we summarize data from our labs and from other groups on the latest brain imaging findings in different chronic pain conditions focusing on results with significant potential for translation into clinical applications. The gaps in the study of chronic pain and brain imaging are highlighted in throughout the overview. Finally, we conclude by discussing the costs and benefits of using brain biomarkers of chronic pain and compare to other potential markers.

Significant ketoacidosis at autopsy: a single-centre systematic review

AimTo examine the value of vitreous beta-hydroxybutyrate and serum acetone in the investigation of sudden unexpected death.MethodsCoroners’ autopsy reports from a provincial UK city, with a population of approximately 900 000, over a 24-month period with significant ketoacidosis were studied. Demographic features, medical history, anatomical and histological findings, and biochemical parameters, including renal function, vitreous glucose, serum and vitreous alcohol, were analysed.ResultsForty-two cases (28 males and 14 females) were identified; 55% had a history of alcohol and/or substance misuse, and mental health problems, particularly depression and anxiety, and 16% were diabetic. In all, 50% of subjects had alcoholic ketoacidosis (AKA), 19% had diabetic ketoacidosis (DKA) and 12% had a history of both diabetes and alcohol abuse. In 19% of cases, an exact cause of ketoacidosis was established. In AKA, the subjects typically had low vitreous glucose and low or undetected blood alcohol levels. All of the subjects with raised vitreous glucose levels had DKA.ConclusionKetoacidosis is relatively common and should be considered as a cause of sudden death, especially in alcoholic patients and patients with diabetes with no clear cause of death at autopsy.

Substance Use and Misuse among Adults with Chronic Obstructive Pulmonary Disease in the United States, 2015–2019: Prevalence, Association, and Moderation

Background: Despite the advancements in chronic obstructive pulmonary disease (COPD) treatment, complications related to COPD exacerbation remain challenging. One associated factor is substance use/misuse among adults with COPD. Fewer studies, however, examined the prevalence and association between COPD and substance use and misuse. In addition, limited knowledge existed about the moderation effects of serious psychological distress and gender among adults with COPD and substance use/misuse. We aimed, therefore, to measure such prevalence, association, and moderation from nationally representative samples in the United States. Method: Data were drawn from the 2015–2019 National Survey on Drug Use and Health. Weighted logistic regressions were used to measure the associations of last-month tobacco (cigarettes, cigars, pipe, and smokeless tobacco products), other licit and illicit substance use (alcohol, marijuana, cocaine, crack, heroin, hallucinogens, and inhalants), and substance misuse (pain relievers, tranquilizers, stimulants, and sedatives) among adults with COPD. Serious psychological distress and gender were tested as moderators in the association between COPD and substance use/misuse. Results: The findings revealed that adults with COPD [Weighted N = 53,115,718) revealed greater odds of cigarettes [adjusted odds ratio (aOR) = 2.48 (95%CI = 1.80–3.42)) and smokeless tobacco (aOR = 3.65 (95%CI = 1.75–7.65)). However, they were less likely to use alcohol (aOR = 0.61 (95%CI = 0.45–0.84)). Adults with COPD who had serious psychological distress were more likely to use pipe tobacco and alcohol; however, they were less likely to use hallucinogens and inhalants. Finally, males compared to females with COPD were less likely to use smokeless tobacco. Conclusion: Adults with COPD in the United States were more likely to use tobacco products and less likely to use alcohol. In addition, serious psychological distress and gender were moderators in associations between COPD and substance use but not in substance misuse. Future studies should longitudinally assess the factors that may contribute to the initiation and progression of substance use and misuse among adults with COPD.