The role of anxiety and depressive symptoms in mediating the relationship between subjective sleep quality and cognitive function among older adults in China

Deterioration of cognitive function has a significant impact on the unavoidable burden on individuals, families, and society. This study aimed to examine the serial multiple mediating effects of anxiety and depressive symptoms on the relationship between subjective sleep quality and cognitive function among older adults in China. We selected 6442 Chinese older adults aged 65 years and older from the 2018 Chinese Longitudinal Healthy Longevity Survey. The SPSS PROCESS macro was employed to perform simple and serial multiple mediation analyses. Subjective sleep quality, depressive symptoms, anxiety symptoms, and cognitive function were significantly related (P < 0.01). Poor sleep quality can have a direct negative influence on cognitive function among older adults (effect = −0.110; 95 % CI = [−0.166, −0.053]), but it can also have an indirect negative impact via three pathways: the independent mediation of anxiety symptoms (effect = −0.028; 95 % CI = [−0.048, −0.011]), the independent mediation of depressive symptoms (effect = −0.014; 95 % CI = [−0.026, −0.002]), and the serial mediation of anxiety and depressive symptoms (effect = −0.009; 95 % CI = [−0.017, −0.001]). This study used a cross-sectional design, which restricts the ability to infer causal relationships. The effect of subjective sleep quality on cognitive function was serially mediated by anxiety and depressive symptoms among older adults. Diverse therapies targeted at improving sleep quality in older adults may improve mood and cognitive functioning.