Abstract
Anxiety and insomnia are correlated in older adults and their caregivers, yet the moderating role of mental health literacy (MHL) is unclear. This study aimed to explore dyadic effects of anxiety on insomnia among Chinese chronically ill older adults and family caregivers across age groups and whether MHL moderates these effects. Data came from 1033 dyads of older adults and their family caregivers in China through the Guangdong Mental Health Survey. Anxiety was assessed with the Generalized Anxiety Disorder-7, insomnia with the Insomnia Severity Index, and MHL with the Chinese National Mental Health Literacy Scale (consisting of mental health knowledge, attitudes, and capacity). The Actor-Partner Interdependence Moderation Model was applied for analysis. Young caregivers' mental health attitudes, β = -0.558, p = 0.002, mitigated the effect of their anxiety on their insomnia, while older adults' mental health knowledge, β = 0.428, p = 0.019, enhanced this relationship. Older adults' mental health attitudes, β = -0.731, p = 0.004, reduced the impact of middle-aged caregivers' anxiety on the latter's insomnia. Middle-aged caregivers' mental health capacity, β = -0.367, p = 0.004, attenuated the effect of older adults' anxiety on caregivers' insomnia. No significant moderating effects were observed in the dyad group of older adults and older caregivers. Within caregiving dyads, enhancing MHL can potentially reduce the impact of anxiety on insomnia. Interventions aimed at improving the mental health attitudes of older adults and caregivers are more likely to alleviate anxiety and insomnia than mental health knowledge and capacity.