Brain structure is related to its ability to resist external pathogens. Furthermore, there are several abnormal anatomical brain events and central system symptoms associated with COVID-19. This study, which was conducted based on genetic variables, aimed to identify the causal association between brain structure and COVID-19 phenotypes. We performed a two-sample bidirectional Mendelian randomization analysis using genetic variables obtained from large genome-wide association studies as instruments to identify the potential causal effects of various brain imaging-derived phenotypes (BIDPs) traits on susceptibility, hospitalisation, and severity of COVID-19. We explored the genetic correlations of 1325 BIDPs with the susceptibility, hospitalisation, and severity of COVID-19 using Linkage Disequilibrium Score Regression. We observed a causal relationship between increased cortical thickness of the left inferior temporal area and an increased risk of increased COVID-19 infection (p = 4.29 × 10-4) and hospitalisation (p = 3.67 × 10-3).Moreover, the larger total surface area of the whole brain was negatively correlated with the risk of hospitalisation for COVID-19. Furthermore, there was a significant causal association between increased cerebrospinal fluid volume and decreased severity of . In a conclusion, we provide new insights into the causal association between BIDPs and COVID-19 phenotypes, which may help elucidate the aetiology of COVID-19.

BackgroundAndrogen sensitivity, which was established as the leading etiology of androgenetic alopecia (AGA) and benign prostatic hyperplasia (BPH), plays an important role in SARS-CoV-2 infection. Vaccination is essential for AGA and BPH patients in view of the high risk from SARS-CoV-2 infection.PurposeWe aimed to investigate the associated factors for SARS-CoV-2 vaccination and its side effects in populations with AGA and BPH.MethodWe collected the data on SARS-CoV-2 vaccination and adverse reactions of male AGA and BPH patients visited the outpatient of Xiangya hospital by telephone and web-based questionnaires. Vaccination rate and adverse reactions were compared by different vaccine types and use of anti-androgen therapy.ResultA total of 457 AGA patients and 397 BPH patients were recruited in this study. Among which, 92.8% AGA patients and 61.0% BPH patients had at least the first dose of SARS-CoV-2 vaccination (p < 0.001). Having comorbidities and use of anti-androgen therapy increased the risk of un-vaccination among AGA by 2.875 and 3.729 times, respectively (p < 0.001). Around 31.1% AGA patients and 9.5% BPH patients presented adverse reactions, which were mostly mild. Anti-androgen therapy increased the inclination of injection site pain after vaccination (18.7% vs 11.9%; OR: 1.708, 95% CI: 1.088-2.683, p = 0.019).ConclusionCo-existence of other systemic diseases and anti-androgen therapy were the limiting factors for SARS-CoV-2 unvaccination, especially in AGA patients. The importance of SARS-CoV-2 vaccines should be strengthened and popularized in androgen sensitive phenotypes.

In this study, we aimed to investigate the causal associations of brain structure with bone mineral density (BMD). Based on the genome-wide association study (GWAS) summary statistics of 1 325 brain imaging-derived phenotypes (BIDPs) of brain structure from the UK Biobank and GWAS summary datasets of 5 BMD locations, including the total body, femoral neck, lumbar spine, forearm, and heel from the GEFOS Consortium, linkage disequilibrium score regression (LDSC) was conducted to determine the genetic correlations, and Mendelian randomization (MR) was then performed to explore the causal relationship between the BIDPs and BMD. Several sensitivity analyses were performed to verify the strength and stability of the present MR outcomes. To increase confidence in our findings, we also performed confirmatory MR between BIDPs and osteoporosis. LDSC revealed that 1.93% of BIDPs, with a false discovery rate (FDR) < 0.01, were genetically correlated with BMD. Additionally, we observed that 1.31% of BIDPs exhibited a significant causal relationship with BMD (FDR < 0.01) through MR. Both the LDSC and MR results demonstrated that the BIDPs “Volume of normalized brain,” “Volume of gray matter in Left Inferior Frontal Gyrus, pars opercularis,” “Volume of Estimated Total Intra Cranial” and “Volume-ratio of brain segmentation/estimated total intracranial” had strong associations with BMD. Interestingly, our results showed that more left BIDPs were causally associated with BMD, especially within and around the left frontal region. In conclusion, a part of the brain structure causally influences BMD, which may provide important perspectives for the prevention of osteoporosis and offer valuable insights for further research on the brain-bone axis.