Multi-ancestry meta-analysis of tobacco use disorder identifies 461 potential risk genes and reveals associations with multiple health outcomes.

Tobacco use disorder (TUD) is the most prevalent substance use disorder in the world. Genetic factors influence smoking behaviours and although strides have been made using genome-wide association studies to identify risk variants, most variants identified have been for nicotine consumption, rather than TUD. Here we leveraged four US biobanks to perform a multi-ancestral meta-analysis of TUD (derived via electronic health records) in 653,790 individuals (495,005 European, 114,420 African American and 44,365 Latin American) and data from UK Biobank (ncombined = 898,680). We identified 88 independent risk loci; integration with functional genomic tools uncovered 461 potential risk genes, primarily expressed in the brain. TUD was genetically correlated with smoking and psychiatric traits from traditionally ascertained cohorts, externalizing behaviours in children and hundreds of medical outcomes, including HIV infection, heart disease and pain. This work furthers our biological understanding of TUD and establishes electronic health records as a source of phenotypic information for studying the genetics of TUD.

Prevention of external auditory canal exostosis in the Colorado whitewater community.

CONTEXT: External auditory canal exostoses (EACE) are bony formations that develop insidiously in the auditory meatus from chronic exposure to cold water and, in severe cases, require surgery. This condition has been understudied in the whitewater kayakers and not yet studied in the riverboarding population. Precautions such as earplugs are thought to prevent the formation of EACE because they mechanically block cold water from contacting the sensitive skin in the external auditory canal; however, earplugs are not commonly utilized by athletes. Inquiring about hobbies and the use of protective equipment can be done during osteopathic physicians' preventive care visits. OBJECTIVES: This article aims to determine the prevalence of EACE in Colorado whitewater athletes and their attitudes about wearing ear protection before and after an educational intervention directed at increasing awareness and prevention of EACE. METHODS: In July 2020, participants of this cross-sectional study completed a 10-min survey that collected demographics, whitewater experience, and perceptions of EACE, followed by an educational intervention. Participant ears were photographed utilizing a digital otoscope to assess EACE, and severity ratings were categorized into one of four occlusion levels: none (0%), mild (<25%), moderate (25-75%), or severe (>75%). Spearman correlation coefficients and Wilcoxon signed-rank tests were utilized to assess changes in attitudes before and after the educational intervention. RESULTS: Eighty-one participants (mean [SD] age = 36.3 [12.6] years, 25.9% female) completed the study: 74 kayakers and seven riverboarders. After the intervention, 60.5% (49/81) (p<0.001) reported greater understanding of EACE and 75.0% (60/80) were more likely to wear ear protection (p<0.001). Most (58.0%, 47/81) never wore ear protection. Of the 61 (75.0%) participants with at least one ear severity rating, most (55.7%, 34/61) had moderate EACE, 29.5% (18/61) had no to mild EACE, and 14.8% (9/61) had severe EACE (p<0.001). Impaired hearing was the biggest barrier to utilizing ear protection (51.6%, 33/64). CONCLUSIONS: Our results suggested that the educational intervention improved understanding of EACE and may increase utilization of ear protection in this population. Such prevention efforts may lead to better health of whitewater paddlers by reducing the incidence of EACE. Encouraging osteopathic physicians to inquire about hobbies and protective equipment during primary care preventive visits is essential to help keep athletes in the river doing what they love for longer, contributing to a healthier and happier whole person.

Relationship between hypothermia and blood loss in adult patients undergoing open lumbar spine surgery.

CONTEXT: Intraoperative blood loss during open lumbar spine surgery is associated with adverse events and is a contributor to higher medical costs. Intraoperative hypothermia has been shown to increase blood loss and postoperative allogeneic blood transfusion rates in other realms of orthopedic surgery, but it has not been studied extensively in patients undergoing spine surgery. OBJECTIVE: To determine whether a clinically relevant association exists between intraoperative core body temperature and blood loss or transfusion rates in adult patients undergoing open lumbar spine surgery. METHODS: In this retrospective medical record review, the surgical records of 174 adult patients who underwent open, nonmicroscopically assisted lumbar spine surgery performed by a single surgeon at a single institution were evaluated. Maximum, minimum, and average temperature, hypothermic temperature, and temperature range parameters were compared with intraoperative, total, and net blood loss and blood transfusion parameters. Additional patient demographic and perioperative characteristics were compared with blood loss and transfusion parameters to determine potential confounders. Analysis of variance, Spearman rank correlation, and generalized multiple linear regression analysis were performed to test for an association between temperature and blood loss or allogeneic transfusion rates. Statistical significance was set at P≤.05. RESULTS: After implementation of exclusion criteria, 160 patient records and 168 surgical procedures were included in the analysis. For patients whose temperature decreased to a hypothermic level at some point during the procedure, hypothermic maximum temperature was protective against blood loss on bivariate analysis (P≤.02), but this finding lost significance after multivariate regression analysis (P>.09). Temperature range was associated with increased blood loss on bivariate analyses (P<.001) but also lost significance after adjusting for covariates in regression analysis (P≥.65). Surgery type (P≤.001) and operative time (P≤.001) were the most robust predictors of increased blood loss (P=.005) and were significantly associated with temperature (P<.001). CONCLUSION: No effect was found on perioperative blood loss from any temperature parameter or hypothermia in adult patients who underwent lumbar spine surgery once covariates were controlled for with multivariate analysis. One possible interpretation of these results is that the effect of temperature on blood loss can be explained by its strong relationship to the confounders of operative time and surgery type.