Obesity is highly prevalent and disabling, especially in individuals with severe mental illness including bipolar disorders (BD). The brain is a target organ for both obesity and BD. Yet, we do not understand how cortical brain alterations in BD and obesity interact.

We obtained body mass index (BMI) and MRI-derived regional cortical thickness, surface area from 1231 BD and 1601 control individuals from 13 countries within the ENIGMA-BD Working Group. We jointly modeled the statistical effects of BD and BMI on brain structure using mixed effects and tested for interaction and mediation. We also investigated the impact of medications on the BMI-related associations.

BMI and BD additively impacted the structure of many of the same brain regions. Both BMI and BD were negatively associated with cortical thickness, but not surface area. In most regions the number of jointly used psychiatric medication classes remained associated with lower cortical thickness when controlling for BMI. In a single region, fusiform gyrus, about a third of the negative association between number of jointly used psychiatric medications and cortical thickness was mediated by association between the number of medications and higher BMI.

We confirmed consistent associations between higher BMI and lower cortical thickness, but not surface area, across the cerebral mantle, in regions which were also associated with BD. Higher BMI in people with BD indicated more pronounced brain alterations. BMI is important for understanding the neuroanatomical changes in BD and the effects of psychiatric medications on the brain.

Studying phenotypic and genetic characteristics of age at onset (AAO) and polarity at onset (PAO) in bipolar disorder can provide new insights into disease pathology and facilitate the development of screening tools.

To examine the genetic architecture of AAO and PAO and their association with bipolar disorder disease characteristics.

Genome-wide association studies (GWASs) and polygenic score (PGS) analyses of AAO (n = 12 977) and PAO (n = 6773) were conducted in patients with bipolar disorder from 34 cohorts and a replication sample (n = 2237). The association of onset with disease characteristics was investigated in two of these cohorts.

Earlier AAO was associated with a higher probability of psychotic symptoms, suicidality, lower educational attainment, not living together and fewer episodes. Depressive onset correlated with suicidality and manic onset correlated with delusions and manic episodes. Systematic differences in AAO between cohorts and continents of origin were observed. This was also reflected in single-nucleotide variant-based heritability estimates, with higher heritabilities for stricter onset definitions. Increased PGS for autism spectrum disorder (β = −0.34 years, s.e. = 0.08), major depression (β = −0.34 years, s.e. = 0.08), schizophrenia (β = −0.39 years, s.e. = 0.08), and educational attainment (β = −0.31 years, s.e. = 0.08) were associated with an earlier AAO. The AAO GWAS identified one significant locus, but this finding did not replicate. Neither GWAS nor PGS analyses yielded significant associations with PAO.

AAO and PAO are associated with indicators of bipolar disorder severity. Individuals with an earlier onset show an increased polygenic liability for a broad spectrum of psychiatric traits. Systematic differences in AAO across cohorts, continents and phenotype definitions introduce significant heterogeneity, affecting analyses.

Alberta is a Canadian province with a high prevalence of multiple sclerosis (MS). In this ecological study, we examined group differences in health care utilization among persons with MS (pwMS) living within different regions of the province.

pwMS were identified from provincial administrative databases spanning 2002–2011. Utilization of health care services was determined for a 2-year period (April 2010–March 2012). Residential postal codes placed patients into their provincial health care zones. As data were provided to the investigators in an aggregated form, tests of statistical significance and confounding were not performed.

In total, 11,721 pwMS were identified. During the 2-year observation period, 96.2% of pwMS accessed a family physician and 57.1% accessed a neurologist. Nearly all (99.0%) pwMS who received neurologist care in Calgary visited an MS clinic, in contrast to Edmonton where a larger proportion (34.8%) received solely community neurologist care. More pwMS living in Edmonton accessed the ED (41.1%) compared to Calgary (35.7%), and the rate of visits per pwMS was higher in Edmonton (1.07/pwMS) than in Calgary (0.81/pwMS). The frequency of inpatient admissions was similar.

Over 2 years, most pwMS accessed primary care and over half saw a neurologist. Despite a similar frequency of inpatient admissions, the frequency of ED visits by pwMS was higher in Edmonton compared to Calgary, where more patients received MS clinic care. Although this exploratory study is subject to several limitations, our findings suggest that specialized MS clinics may reduce costly ED visits.

The Best Practices in Social and Behavioral Research Course was developed to provide instruction on good clinical practice for social and behavioral trials. This study evaluated the new course.

Participants across 4 universities took the course (n=294) and were sent surveys following course completion and 2 months later. Outcomes included relevance, how engaging the course was, and working differently because of the course. Open-ended questions were posed to understand how work was impacted.

Participants rated the course as relevant and engaging (6.4 and 5.8/7 points) and reported working differently (4.7/7 points). Participants with less experience in social and behavioral trials were most likely to report working differently 2 months later.

The course was perceived as relevant and engaging. Participants described actions taken to improve rigor in implementing trials. Future studies with a larger sample and additional participating sites are recommended.