Individuals with disabilities face practical and social challenges beyond those experienced by non-disabled individuals, which may increase vulnerability to mental health problems. However, few studies have examined biochemical correlates of psychological health in this population. This study investigated the associations of serum brain-derived neurotrophic factors (BDNF) and adiponectin with anxiety, depression, and stress among deaf adults. A cross-sectional study was conducted among 204 deaf adults aged 18–45 years. Anxiety and depression were assessed using the DASS-21 questionnaire. Body composition analyses were performed using bioelectrical impedance analysis, and serum BDNF and adiponectin levels were measured. Serum BDNF concentrations were inversely associated with anxiety ( r = −0.632, p < 0.001), depression ( r = −0.732, p < 0.001), and stress ( r = −0.795, p < 0.001). Similarly, serum adiponectin concentrations showed significant inverse correlations with anxiety ( r = −0.422, p < 0.001), depression ( r = −0.344, p < 0.001), and stress ( r = −0.446, p < 0.001). In multiple linear regression analyses adjusted for age, sex, and body mass index (BMI), BDNF remained an independent inverse predictor of anxiety ( β = −0.48, p < 0.001), depression ( β = −0.55, p < 0.001), and stress ( β = −0.62, p < 0.001). Adiponectin also remained independently associated with anxiety ( β = −0.19, p = 0.03) and stress ( β = −0.21, p = 0.02). Lower serum BDNF and adiponectin concentrations were independently associated with higher levels of anxiety, depression, and stress among deaf adults. These findings suggest that BDNF, and to a lesser extent adiponectin, may represent potential biomarkers of psychological distress in this population.

Background: Modern lifestyles characterized by artificial light exposure, screen use, and altered sleep routines may be related to eating behaviors and dietary patterns relevant to the gut microbial environment. Although these factors have been investigated individually, limited evidence has examined self-reported light-exposure behaviors, sleep, eating behavior, and gut microbiota-related dietary patterns simultaneously within a single analytical framework. Objective: The aim of this study was to examine associations between five self-reported light-exposure behaviors and the global PSQI score, eating-behavior domains, and FFQ-GM-derived gut microbiota-related dietary pattern scores among adults in the recruited sample. Methods: A cross-sectional study was conducted among 518 adults aged 18–64 years recruited in Amman, Jordan, between April and May 2026 using convenience sampling. Participants completed the LEBA, the Arabic PSQI, the Arabic TFEQ-R18, and an Arabic-adapted gut microbiota-focused food frequency questionnaire (FFQ-GM). Associations were examined using Spearman’s rho and multivariable linear regression; multiplicity across the 25 LEBA factor–outcome coefficient tests was addressed using the Benjamini–Hochberg false discovery rate. Results: In the analyzed sample, 87.3% of participants had a global PSQI score > 5. Several LEBA factor–outcome coefficients had nominal p values < 0.05. Blue-light-filter use was positively associated with the global PSQI score (β = 0.29, p = 0.020), whereas phone use in bed (β = −0.43, p = 0.002) and light exposure before bedtime (β = −0.51, p = 0.009) were negatively associated with the global PSQI score. After false-discovery-rate adjustment across the 25 individual coefficient tests, most individual associations did not remain below the 0.05 threshold; therefore, these coefficient-level findings are interpreted as exploratory. Conclusions: Self-reported light-exposure behaviors were associated with questionnaire-derived sleep scores, eating-behavior domains, and FFQ-GM-derived gut microbiota-related dietary pattern scores. The cross-sectional design does not establish temporal direction, causality, or biological mechanism.