Association of concurrent diabetes and poor sleep with cognitive decline: a 4-year community-based cohort study

Aims: To investigate the association of concurrent diabetes mellitus and poor sleep with cognitive decline in a community-based population. Methods: Cognitively normal adults aged 40 years or older were followed-up for 4 years. Cognitive decline was defined as a decrease of ≥ 4 points on the Chinese Mini-Mental Status from baseline. Sleep quality was assessed using the Pittsburgh Sleep Quality Index. Logistic regression was employed to evaluate associations of diabetes and poor sleep status with cognitive decline. Results: Among 1218 participants, 30 (2.46%) developed cognitive decline during follow-up. Participants with concurrent diabetes and poor sleep had higher odds of cognitive decline (adjusted OR = 5.74, 95% CI: 1.58 – 18.81). The association of the concurrent presence of poor sleep and diabetes with cognitive decline was evident mainly when poor sleep was defined by poor subjective sleep quality, short sleep duration, low sleep efficiency, frequent sleep disturbances, or severe daytime dysfunction (adjusted ORs, 4.17–10.23; all P < 0.05), rather than prolonged sleep latency. The application of broader criteria for dysglycemia (adjusted OR = 4.10, 95% CI: 1.23 – 12.82) corroborated the robustness of these findings. Conclusions: The co-occurrence of diabetes and poor sleep was associated with higher odds of cognitive decline, suggesting the clinical potential of integrated interventions in preserving cognitive health.