OBJECTIVE: Humans are exposed to complex mixtures of environmental chemicals and other factors that can affect their health. Analysis of these mixture exposures presents several key challenges for environmental epidemiology and risk assessment, including high dimensionality, correlated exposure, and subtle individual effects. METHODS: We proposed a novel statistical approach, the generalized functional linear model (GFLM), to analyze the health effects of exposure mixtures. GFLM treats the effect of mixture exposures as a smooth function by reordering exposures based on specific mechanisms and capturing internal correlations to provide a meaningful estimation and interpretation. The robustness and efficiency was evaluated under various scenarios through extensive simulation studies. RESULTS: We applied the GFLM to two datasets from the National Health and Nutrition Examination Survey (NHANES). In the first application, we examined the effects of 37 nutrients on BMI (2011-2016 cycles). The GFLM identified a significant mixture effect, with fiber and fat emerging as the nutrients with the greatest negative and positive effects on BMI, respectively. For the second application, we investigated the association between four pre- and perfluoroalkyl substances (PFAS) and gout risk (2007-2018 cycles). Unlike traditional methods, the GFLM indicated no significant association, demonstrating its robustness to multicollinearity. CONCLUSION GFLM framework is a powerful tool for mixture exposure analysis, offering improved handling of correlated exposures and interpretable results. It demonstrates robust performance across various scenarios and real-world applications, advancing our understanding of complex environmental exposures and their health impacts on environmental epidemiology and toxicology.
Humans ; Environmental Exposure/analysis* ; Linear Models ; Nutrition Surveys ; Environmental Pollutants ; Body Mass Index

Objective To explore the risk factors for oral mucosal pressure injuries(OMPI)in patients with endotracheal intubation in the emergency intensive care unit(EICU)and to construct a nomogram prediction model based on these factors.Methods A case-control study design was adopt-ed to retrospectively collect clinical data from 209 adult patients with endotracheal intubation admitted to EICU.The patients were divided into OMPI group(53 patients)and non-OMPI group(156 pa-tients)based on whether OMPI occurred during the observation period.The clinical data of the two groups were analyzed,and multivariate Logistic regression analysis was used to screen risk factors for OMPI in patients with endotracheal intubation in the EICU.R software was used to draw a nomogram prediction model,and the predictive performance of the model was evaluated through the receiver oper-ating characteristic(ROC)curve,calibration curve,and decision curve analysis.Results Statistical-ly significant differences were observed between the two groups in prone position ventilation,vasocon-strictor use,consciousness at the time of intubation,Acute Physiology and Chronic Health Evaluation Ⅱ(APACHE Ⅱ)score at the time of intubation,and duration of endotracheal intubation(P＜0.05).The results of multivariate Logistic regression analysis showed that prone position ventilation(OR=2.545,95％CI,1.261 to 5.135),vasoconstrictor use(OR=1.984,95％CI,1.162 to 3.387),inability to express complaints at time of intubation(OR=3.618,95％CI,1.891 to 6.924),high APACHE 11 score(OR=2.394,95％CI,1.322 to 4.336),and long duration of endotracheal in-tubation(OR=3.995,95％CI,1.857 to 8.593)were all risk factors for OMPI in patients with en-dotracheal intubation in the EICU(P＜0.05).ROC curve analysis showed that the area under the curve of the nomogram prediction model was 0.881;calibration curve analysis showed that the mean absolute error between the predicted probability and the actual probability of the model was 0.016;and decision curve analysis showed that the prediction model had practical value in clinical practice.Conclusion Prone position ventilation,vasoconstrictor use,inability to express complaints at the time of intubation,high APACHE Ⅱ score,and long duration of endotracheal intubation are all risk factors for OMPI in patients with endotracheal intubation in the EICU.The nomogram model con-structed based on these factors has good predictive performance for OMPI risk.

Objective:To evaluate the efficacy and safety of 308-nm excimer lamp and 308-nm excimer laser in the treatment of pediatric vitiligo.Methods:Clinical data were collected from children with stable vitiligo who received targeted phototherapy at the Department of Dermatology of Xijing Hospital from 2010 to 2015, and retrospectively analyzed. The patients were treated with either 308-nm excimer laser or 308-nm excimer lamp, and all were given topical drugs. The treatment lasted for at least 3 months, and follow-up for at least 6 months. The severity of vitiligo was assessed using the Vitiligo Area and Severity Index (VASI) score. The efficacy was evaluated after 3 months of treatment, and at least a 50% reduction in the VASI score (VASI50) was defined as "effectiveness". A logistic regression model was constructed using treatment efficacy as the dependent variable to screen factors related to the treatment outcome. The Wilcoxon signed-rank test was used to compare skewed data before and after treatment. Adverse reactions during treatment were recorded to evaluate the safety of targeted phototherapy.Results:A total of 194 children with stable vitiligo were included, comprising 103 males (53.1%) and 91 females (46.9%), with the age being 6 to 14 (10.2 ± 2.3) years. Among them, 138 (71.1%) received 308-nm excimer laser therapy, while 56 (28.9%) received 308-nm excimer lamp therapy. The VASI score ( M [ Q1, Q3]) was 0.12 (0.05, 0.40) at the baseline, significantly decreased to 0.06 (0.02, 0.19) after 3 months of treatment ( Z = 12.02, P < 0.001). After 3 months of treatment, 52 patients achieved VASI50, and 30 achieved VASI75, resulting in an overall response rate of 42.3% (82/194). Specifically, in the 308-nm excimer laser group, 38 patients achieved VASI50 and 26 achieved VASI75, with a response rate of 46.4% (64/138) ; in the 308-nm excimer lamp group, 14 patients achieved VASI50 and 4 achieved VASI75, yielding a response rate of 32.1% (18/56). Univariate logistic regression analysis indicated that lesions located on the head and neck or the trunk were more prone to repigmentation compared with those on the limbs ( OR = 3.56, 95% CI: 1.15 - 11.02, P = 0.027; OR = 6.58, 95% CI: 1.81 - 23.96, P = 0.004, respectively) ; additionally, facial lesions around the eyes were more prone to repigmentation compared with lesions on other facial areas ( OR = 4.58, 95% CI: 1.10 - 19.11, P = 0.037), and hair involvement in vitiligo lesions on the head and neck made repigmentation less likely to occur compared with lesions without hair involvement ( OR = 0.31, 95% CI: 0.13 - 0.75, P = 0.010). Multivariate logistic regression analysis revealed that the periorbital region was the most favorable site for repigmentation among facial areas ( OR = 5.37, 95% CI: 1.18 - 24.34, P = 0.029), and hair involvement in vitiligo lesions on the head and neck was an independent risk factor for phototherapy-induced repigmentation ( OR = 0.28, 95% CI: 0.08 - 0.96, P = 0.042). Among the 194 patients treated with targeted phototherapy for 3 months, 33 experienced short-term treatment-related adverse reactions, including erythema, blisters, desquamation, itching, and pain; most adverse reactions were mild, and no severe adverse reactions were observed. Conclusion:Targeted phototherapy using 308-nm excimer laser or 308-nm excimer lamp was safe and effective for the treatment of pediatric vitiligo.