Genetic predisposition to high BMI increases risk of early life respiratory infections and episodes of severe wheeze and asthma

Neuroticism and asthma: Mendelian randomization analysis reveals causal link with mood swings and BMI mediation

BACKGROUND

Neuroticism has been associated with asthma, but the nature of this relationship remains unclear due to limited understanding of the impact of psychological factors on asthma risk. While Neuroticism is known to affect various health outcomes, its specific role in respiratory conditions like asthma is not fully understood.

METHODS

We conducted Mendelian randomization (MR) analyses using genome-wide association studies (GWAS) to explore the causal link between 12 Neuroticism traits and asthma. Various MR approaches, including MR-PRESSO, were employed, with validation through independent GWAS and the FinnGen dataset.

RESULTS

MR-PRESSO revealed a significant causal relationship between mood swings and asthma (OR: 1.927, 95% CI: 1.641-2.263), surpassing the Bonferroni-corrected threshold (p < 4.167 × 10-³). Mood swings emerged as the only significant trait associated with asthma, with reverse MR analyses showing no causal links for other traits. Secondary analyses supported these findings. Multivariate analysis showed mood swings increased asthma risk, independent of smoking, BMI, and air pollution. Mediation analysis indicated that BMI partially mediates the mood swing-asthma relationship, accounting for 9.87% of the effect (95% CI: 4.54%-15.2%, p = 2.850 × 10-4).

CONCLUSION

Mood swings elevate asthma risk, with BMI partially mediating this effect, highlighting a potentially significant pathway through which psychological traits influence asthma.

Global burden of asthma attributable to high body mass index in older adults 1990-2021 and prediction to 2050: An analysis of Global Burden of Disease Study 2021

Background

Previous studies have shown that high body mass index was a primary risk factor for asthma, particularly impacting older adults. This study aimed to assess the spatial and temporal trends for asthma burden attributable to high body mass index in older adults from 1990 to 2021 and to project trends up to 2050.

Method

We extracted data from the Global Burden of Disease Study 2021 for population aged over 60 years with asthma attributable to high BMI. Relevant indicators included number of deaths, disability-adjusted life years, mortality, and disability-adjusted life years rates and the rates were directly standardized. Spearman rank correlation test tested the burden against the Socio-demographic Index (SDI). Decomposition analysis was used to decompose changes in burden according to population structure, population growth, and epidemiologic changes. The Bayesian age-period-cohort model was used to predict the burden.

Results

From 1990 to 2021, despite downward trends in global mortality and disability-adjusted life-year rates, global asthma deaths, and disability-adjusted life years attributable to high body mass index increase by 69% and 46%, rising to 43,628 cases (95% CI: 18,366-71 088) and 1,223,969 years (95% CI: 526,972-1 945,426). Age-standardized mortality rates and disability-adjusted life years rates were more severe in regions with lower SDI, such as Oceania. Mortality rates and disability-adjusted life-year rates increased with age, with a higher burden observed in females compared to males. Population growth had a significant impact on the increase in deaths and disability-adjusted life years from 1990 to 2021, contributing approximately 158% and 222%, respectively. Asthma deaths and disability-adjusted life years attributable to high body mass index will continue to rise to 101,252 cases and 2,941,172 years up to 2050.

Conclusion

The global asthma burden due to high body mass index in older adults has risen significantly and is expected to continue this trend, highlighting the importance of developing public health strategies to address this issue.

Clinical characteristics and risk factors in pneumoconiosis patients with asthma

To investigate the risk factors for pneumoconiosis associated with asthma. A total of 256 pneumoconiosis patients diagnosed by chest X-ray at our hospital were analyzed. Based on pulmonary function tests, pneumoconiosis cases were divided into non-asthma and asthma-complicated groups. Clinical characteristics, clinical manifestations, and laboratory indicators of both groups were collected and compared. Risk factors for asthma in pneumoconiosis patients were identified using univariate and multivariate logistic regression analyses. Among the 256 pneumoconiosis patients, 79 had asthma. The age, BMI, incidence of pneumoconiosis categories II and III, exposure time, IgE levels, FeNO levels, and the incidence of wheezing and dyspnea were all higher in the asthma group compared to the non-asthma group. Conversely, FEV1, FEV1%predicted, FEV1/FVC, and the incidence of cough and expectoration were lower in the asthma group. Multivariate logistic regression analysis revealed that exposure time, low level of FEV1 and FEV1/FVC, high IgE levels, elevated FeNO, and wheezing were independent risk factors for asthma in pneumoconiosis patients. In this study, the prevalence of pneumoconiosis complicated with asthma was 30.9%. High exposure time, elevated IgE levels, increased FeNO levels, incidence of wheezing, low level of FEV1, and FEV1/FVC suggest that pneumoconiosis patients are significantly at increased risk of asthma.

Body mass index trajectories from birth to early adulthood and lung function development

BACKGROUND

Few studies have investigated the influence of body mass index (BMI) trajectories on lung function covering the entire growth period.

METHODS

We conducted a prospective study using data from the Swedish BAMSE birth cohort. Latent class mixture modelling was employed to examine the diversity in BMI z-scores from birth to 24 years of age. Participants with four or more BMI z-scores were included (n=3204, 78.4%). Pre-bronchodilator spirometry was tested at 8, 16 and 24 years, while post-bronchodilator spirometry, multiple-breath nitrogen washout (for lung clearance index) and urinary metabolomics data were assessed at 24 years.

RESULTS

Six distinct BMI development groups were identified. Compared to the stable normal BMI group, the accelerated increasing BMI group exhibited reduced pre- and post-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio z-scores (pre: β= -0.26, 95% CI -0.44- -0.08; post: β= -0.22, 95% CI -0.39- -0.05), along with elevated lung clearance index (0.30, 95% CI 0.22-0.42) at 24 years. The persistent high BMI group demonstrated lower FEV1 (-0.24, 95% CI -0.42- -0.05) and FVC (-0.27, 95% CI -0.45- -0.01) z-score growth between 16 and 24 years, and elevated lung clearance index (0.20, 95% CI 0.03-0.39) at 24 years. However, those impairments were not observed in the accelerated resolving BMI group. Conversely, the persistent low BMI group displayed persistently decreased FEV1 and FVC from 8 to 24 years, as well as decreased lung function growth. Additionally, histidine-related metabolites were associated with pre- and post-bronchodilator FEV1 (hypergeometric false discovery rate=0.008 and <0.001, respectively).

CONCLUSIONS

Early interventions aiming for normal BMI during childhood may contribute to improved lung health later in life.

Inhibitory neuron links the causal relationship from air pollution to psychiatric disorders: a large multi-omics analysis

Psychiatric disorders are severe health challenges that exert a heavy public burden. Air pollution has been widely reported as related to psychiatric disorder risk, but their casual association and pathological mechanism remained unclear. Herein, we systematically investigated the large genome-wide association studies (6 cohorts with 1,357,645 samples), single-cell RNA (26 samples with 157,488 cells), and bulk-RNAseq (1595 samples) datasets to reveal the genetic causality and biological link between four air pollutants and nine psychiatric disorders. As a result, we identified ten positive genetic correlations between air pollution and psychiatric disorders. Besides, PM2.5 and NO2 presented significant causal effects on schizophrenia risk which was robust with adjustment of potential confounders. Besides, transcriptome-wide association studies identified the shared genes between PM2.5/NO2 and schizophrenia. We then discovered a schizophrenia-derived inhibitory neuron subtype with highly expressed shared genes and abnormal synaptic and metabolic pathways by scRNA analyses and confirmed their abnormal level and correlations with the shared genes in schizophrenia patients in a large RNA-seq cohort. Comprehensively, we discovered robust genetic causality between PM2.5, NO2, and schizophrenia and identified an abnormal inhibitory neuron subtype that links schizophrenia pathology and PM2.5/NO2 exposure. These discoveries highlight the schizophrenia risk under air pollutants exposure and provide novel mechanical insights into schizophrenia pathology, contributing to pollutant-related schizophrenia risk control and therapeutic strategies development.

Graphical Abstract