Healthcare utilisation and health-related quality of life of severe asthma patients in Singapore

Association of residential land cover and wheezing among children and adolescents: A cross-sectional study in five provinces of China

The association between residential land cover (RLC) and wheezing remains poorly understood. This study aimed to investigate the association between RLC and wheezing in childhood and adolescence. A cross-sectional survey was conducted among children and adolescents in five provinces of China. Land cover data were obtained from the Cross-Resolution Land-Cover mapping framework based on noisy label learning, classifying land cover into five categories: cropland, forest, grass/shrubland, wetland, and impervious. Generalized linear mixed models were employed to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the risk of wheezing. Mediation analysis was employed to investigate whether ambient particulate matter (PM2.5) acts as a mediator in the association between RLC and wheezing. A total of 12,875 participants were included in the study, comprising 318 patients and 12,557 controls. Cropland500m was significantly associated with decreased odds of wheezing (OR: 0.929, 95% CI: 0.879-0.982), while impervious surfaces500m significantly was associated with increased odds of wheezing (OR: 1.056, 95% CI: 1.019-1.096) in all participants. In the stratified analysis, significant differences were found in the main outcomes between the adolescence group (age ≥10 years) and the childhood group (age <10 years) (Pinteraction < 0.05), while no significant differences were observed between the southern and northern regions, or between male and female respondents. Mediation analysis revealed that PM2.5 partially mediated the association between cropland500m and impervious surfaces500m with wheezing. RLC plays a significant role in wheezing during childhood and adolescence, with cropland offering protection and impervious surfaces posing a heightened risk.

Predictors of persistent poor control and validation of ASSESS score: Longitudinal 5-year follow-up of severe asthma cohort

Background

Longitudinal predictors of persistent poor asthma control in severe asthma (SA) cohort remain scarce. The predictive value of the asthma severity scoring system (ASSESS) in the SA cohort outside the original study and in the Asian population is unknown.

Objective

We sought to determine the 5-year longitudinal outcome of patients with SA and validate the use of ASSESS score in predicting future outcomes in SA.

Methods

A prospective longitudinal observational study of patients with SA attending the multidisciplinary specialist SA clinic of the Singapore General Hospital from 2011 to 2021 was conducted. The number of exacerbations and asthma control test results were recorded yearly for 5 consecutive years. The ASSESS score was computed at baseline, and the area under the receiver-operating characteristic curve for predicting persistent poor asthma control was generated.

Results

Of the 489 patients recruited into the study, 306 patients with 5-year follow-up data were analyzed. Seventy-three percent had type 2 inflammation with increased overall exacerbations over 5 years (rate ratio, 2.55; 95% CI, 1.31-4.96; P = .006) relative to non-type 2 SA. In the multivariate model, bronchiectasis, gastroesophageal reflux disease, and an asthma control test score of less than 20 were significantly associated with persistent poor asthma control over 5 years. ASSESS scores were good at predicting persistent poor asthma control with an area under the receiver-operating characteristic curve of 0.71 (95% CI, 0.57-0.84).

Conclusions

Bronchiectasis and gastroesophageal reflux disease are predictors for persistent poor asthma control and targeted traits for precision medicine in SA. The ASSESS score has a good prediction for persistent poor asthma control over 5 years.

Less Social Deprivation Is Associated With Better Health-Related Quality of Life in Asthma and Is Mediated by Less Anxiety and Better Sleep Quality

BACKGROUND

Previous studies on health-related quality of life (HRQoL) in asthma have mainly focused on clinical and environmental determinants. Little is known about the role of social determinants on HRQoL in asthma.

OBJECTIVES

We aimed to investigate the association between social deprivation and HRQoL in asthma.

METHODS

A total of 691 adult asthmatics from Canada, India, New Zealand, and the United Kingdom were administered a digital questionnaire containing demographic information and questions about social and psychological attributes, sleep disturbances, and alcohol abuse. HRQoL was measured using the Short Form of the Chronic Respiratory Questionnaire (SF-CRQ). We analyzed the direct and indirect relationships between social deprivation and HRQoL using structural equation models with social deprivation as a latent variable. We tested for mediation via anxiety, depression, sleep disturbances, and alcohol abuse.

RESULTS

We found that less social deprivation (latent variable) was directly associated with better SF-CRQ domain scores such as dyspnea (regression coefficient β: 0.33; 95% confidence interval [CI]: 0.07 to 0.58), fatigue (β: 0.39; 95% CI: 0.14 to 0.64), and emotional function (β: 0.37; 95% CI: 0.11 to 0.62), but with the worse mastery score (β: -0.29; 95% CI: -0.55 to -0.03); however, those associations varied across participating countries. We also observed that among all individual social deprivation indicators, education, companionship, emotional support, instrumental support, and social isolation were directly associated with HRQoL, and the relationship between social deprivation and HRQoL was mediated through anxiety and sleep disturbances.

CONCLUSIONS

Our results demonstrated that less social deprivation was directly, and indirectly through less anxiety and better sleep quality, associated with better HRQoL in asthma.