BackgroundPrevious studies have suggested that certain personal psychological variables (e.g., life satisfaction and cognitive function) and physical variables (e.g., body mass index [BMI]) are significantly associated with individuals’ anxiety symptoms. However, relevant research on elderly is lagging and no studies have yet investigated the combined impact of these variables on anxiety. Thus, we conducted the present study to investigate the potential moderator role of BMI and the potential mediator role of cognitive function underlying the relationship between life satisfaction and anxiety symptoms in Chinese elderly based in Hong Kong.MethodsSixty-seven elderly aged 65 years old and above were recruited from the local elderly community centres in this pilot study. Each participant underwent a systematic evaluation using the Satisfaction with Life Scale (SWLS), Hong Kong Version of the Montreal Cognitive Assessment (HK-MoCA), and the Hamilton Anxiety Rating Scale (HAM-A) and were measured for their body weight and height. Regression analysis using the bootstrapping method was employed to test the hypothesized moderated mediation model.ResultsOur findings demonstrated the overall model accounted for 23.05% of the variance in scores of HAM-A (F (8, 57) = 2.134, p = 0.047) in Chinese elderly. There was a significant association between life satisfaction and anxiety symptoms (p = 0.031), indicating that individuals with higher life satisfaction were associated with less anxiety symptoms. Moreover, this relationship was positively moderated by BMI (b = 0.066, 95% CI [0.004, 0.128]), especially in Chinese elderly with BMI at a lower level (b = -0.571, 95% CI [-0.919, -0.224]) and an average level (b = -0.242, 95% CI [-0.460, -0.023]). No significant mediator role was detected for cognitive function (b = -0.006, 95% CI [-0.047, 0.044]) in our model.ConclusionsOur findings suggest that increased life satisfaction can reduce anxiety symptoms among Chinese elderly as their BMI decreases (when BMI ranged between “mean - 1SD” and “mean” of the population). The significant interaction between psychological and physical factors underlying anxiety symptoms found in this study, presents a promising opportunity for translation into multi-level psychological and physical interventions for the management of anxiety in ageing patients during clinical practice.