Associations of the planetary health diet index (PHDI) with asthma: the mediating role of body mass index.

BACKGROUND: Given the global shifts in environmental conditions and dietary habits, understanding the potential impact of dietary factors and body mass index (BMI) on respiratory diseases, including asthma, is paramount. Investigating these relationships can contribute to the formulation of more effective prevention strategies. The Planetary Health Diet Index (PHDI), a dietary scoring system that balances human health with environmental sustainability, underscores the importance of increasing the consumption of plant-based foods while reducing the intake of red meat, sugar, and highly processed foods. The objective of this study was to assess the association between PHDI and the prevalence of asthma and the mediation effect of BMI in a US general population. METHODS: This study utilized data from 32,388 participants in the National Health and Nutrition Examination Survey (NHANES) spanning from 2005 to 2018. Multivariate logistic regression and weighted quantile sum (WQS) regressions were employed to investigate the association between PHDI, individual nutrients, and asthma. Restricted cubic spline (RCS) analysis explored the linear or non-linear relationship between PHDI and asthma. Interaction analyses were conducted on subgroups to validate the findings. Mediation analysis was performed to examine the effect of BMI on the relationship between PHDI and asthma. RESULTS: There was a significant negative association between PHDI and asthma. After adjusting for covariates, for every 10-point increase in PHDI, there was a 4% decrease in the prevalence of asthma (P = 0.025). Moreover, as PHDI increased, there was a trend towards lower asthma prevalence (P for trend < 0.05). WQS analyses showed consistent associations (OR = 0.93, 95%CI: 0.88, 0.98), with Fiber, Vitamin C, and Protein significant factors. The dose-response curve indicated a linear association between PHDI and asthma, with higher PHDI associated with lower asthma prevalence. Additionally, BMI is significantly positively associated with asthma (P < 0.001), and BMI decreases as the PHDI increases (ß = -0.64, P < 0.001). Mediation analysis indicates that BMI significantly mediates the relationship between PHDI and asthma, with a mediation proportion of 33.85% (P < 0.001). CONCLUSION: The results of this study show a strong negative correlation between PHDI and the prevalence of asthma. In addition, BMI mediated this negative relationship.

Association between life's essential 8 and overactive bladder.

Limited research has explored the relationship between overactive bladder (OAB) and cardiovascular health (CVH). We aim to examine the correlation between OAB and CVH in American adults, utilizing the Life's Essential 8 (LE8). We included 70,190 individuals from the National Health and Nutrition Examination Survey spanning from 2005 to 2018. In our study, the independent variable is LE8 score, where higher scores denote better CVH. The dependent variable is the presence of OAB. We employed multivariable logistic regression along with restricted cubic splines to evaluate the association between LE8 and OAB. Additionally, we performed interaction analyzes on subgroups to validate the findings. There is a significant negative correlation between LE8 scores and OAB. Upon adjusting for all covariates, a 10-point increase in LE8 total score correlated with a 17% decrease in the odds of OAB [0.83 (95% CI 0.78, 0.89)]. Compared to participants with lower LE8 scores, those with higher LE8 scores had a 46% lower probability of developing OAB. Consistent results were also observed in the association between scores of four health behaviors and four health factors and OAB. Furthermore, a notable interaction was observed between LE8 scores and smoking status. This study showed a significant negative correlation between LE8 scores and OAB prevalence.