Sex-specific differences in the genetic and environmental effects on cardiac phenotypic variation assessed by echocardiography.

The drivers of sexual dimorphism in heart failure phenotypes are currently poorly understood. Divergent phenotypes may result from differences in heritability and genetic versus environmental influences on the interplay of cardiac structure and function. To assess sex-specific heritability and genetic versus environmental contributions to variation and inter-relations between echocardiography traits in a large community-based cohort. We studied Framingham Heart Study participants of Offspring Cohort examination 8 (2005-2008) and Third Generation Cohort examination 1 (2002-2005). Five cardiac traits and six functional traits were measured using standardized echocardiography. Sequential Oligogenic Linkage Analysis Routines (SOLAR) software was used to perform singular and bivariate quantitative trait linkage analysis. In our study of 5674 participants (age 49 ± 15 years; 54% women), heritability for all traits was significant for both men and women. There were no significant differences in traits between men and women. Within inter-trait correlations, there were two genetic, and four environmental trait pairs with sex-based differences. Within both significant genetic trait pairs, men had a positive relation, and women had no significant relation. We observed significant sex-based differences in inter-trait genetic and environmental correlations between cardiac structure and function. These findings highlight potential pathways of sex-based divergent heart failure phenotypes.

Posttraumatic stress disorder and psycho-social impairment following snakebite in Northeastern Nigeria.

BACKGROUND: Snakebite is a major public health problem among impoverished rural populations causing considerable morbidity and mortality in West Africa. Despite the huge burden of snakebite in this region, psycho-social impairment following snakebite has not been evaluated. In this study, we assessed for features of posttraumatic stress disorder and psycho-social impairment among rural snakebite victims in Northeastern Nigeria. METHODS: Individuals with previous snakebite managed in our facility, defined as exposed to snakebite, and their matched relatives not exposed to snakebite were invited to participate in the study following community mobilization. A retrospective cohort study was conducted evaluating the presence of psycho-social functioning, posttraumatic stress disorder, quality of life, social disability, cognitive impairment, and psychological morbidity using standard tools administered by the investigators, trained nurses, and community health workers. RESULTS: The prevalence of features of posttraumatic stress disorder among those exposed to snakebite compared to those not exposed to snakebite was 43% and 28%, respectively (risk ratio = 1.53; 95% confidence interval: 1.04-2.24; p = 0.024). Subjects exposed to snakebite had significantly poorer quality of life score in the psychological and social domains (p < 0.05). Other psycho-social complications associated with snakebite were impaired family/school functioning and psychological morbidity. No difference in cognitive functioning was observed between the two groups. CONCLUSIONS: Snakebite is complicated by features of posttraumatic stress disorder, poor quality of life, and psycho-social impairments in northeastern Nigeria. Detection, monitoring, and appropriate management interventions should be provided and made more accessible to snakebite victims to ameliorate mental and psychological impairment.

Gender, race, and electrophysiologic characteristics of the branched recurrent laryngeal nerve.

OBJECTIVES/HYPOTHESIS: The extralaryngeal branching of recurrent laryngeal nerves (RLN) conveys an increased risk of nerve injury during thyroid surgery. We hypothesized that racial and gender variations in prevalence of branched RLN exist. STUDY DESIGN: A retrospective review of all patients who underwent thyroid surgery in a 4-year period in a single surgeon practice. METHODS: The RLN was routinely identified during thyroid surgery. Presence of RLN branching, its distance from the laryngeal nerve entry point (NEP), and functionality of the branches were ascertained. Patient demographics, rates of neural branching, and distance of bifurcation from the NEP were evaluated using statistical analysis. RESULTS: We identified 719 RLNs at risk in 491 patients who underwent central neck surgery. Four hundred and five (82.5%) patients were female and 86 (17.5%) patients were male. There were 218 (44.4%) African American patients and 251 (51.1 %) Caucasian patients. In African American patients, 42.1% RLNs bifurcated compared to 33.2% RLNs in Caucasian (P = 0.017) patients. The RLNs of African American and Caucasian patients bifurcated at comparable distances (P = 0.30). In male patients, 39.1% RLNs bifurcated; whereas in female patients 36.2% RLNs bifurcated (P = 0.53). On average, RLN bifurcation in female patients was at a longer distance from NEP compared to that of male patients (P = 0.012). Electrophysiologic testing found motor fibers in all anterior branches and three posterior extralaryngeal RLN branches. CONCLUSION: African American patients have a higher rate of RLN bifurcation compared to Caucasian patients but no statistically significant difference in distance from NEP. Female patients tend to have longer branching variants of bifid RLNs. RLN motor fibers reside primarily in the anterior branch but may occur in the posterior branch.