Delayed melatonin phase is associated with cognitive dysfunction in severe obese patients: a cross-sectional analysis
Benli Jia, Qi Xue, Chanjuan Chen, Liang Yu, Sheng Wang, Ao Li, Wu Liu, Zijing Dou, Changxiu Ma, Wanying Zhang, Shuting Xu, Peng Zhang, Shengyi Ding, Mingjun Zhang, Yijun Du, Chunxia Huang, Fuqiang ZuBackground:
Severe obesity is associated with both circadian rhythm disturbances and cognitive deficits; however, the specific role of melatonin rhythmicity in neurocognitive dysfunction remains poorly understood. This study aimed to investigate the relationship between detailed salivary melatonin secretion profiles and cognitive performance across multiple domains in patients with severe obesity awaiting bariatric surgery.
Methods:
A total of 54 participants underwent salivary melatonin sampling at seven overnight time points. Cosinor analysis was used to extract circadian parameters, including mesor, amplitude, and acrophase. Neuropsychological assessments evaluated executive function, processing speed, memory, and general intelligence. The primary outcome was performance on the Stroop test, which captures core aspects of processing speed, executive function, and attention. Other neuropsychological measures, including IQ, MQ, and Trail Making Test performance, were considered secondary outcomes. Multivariable linear regression models, adjusted for demographic and metabolic covariates, were used to examine the associations between melatonin parameters and cognitive outcomes.
Results:
Participants exhibited substantial interindividual variation in melatonin profiles. A later melatonin acrophase was significantly associated with reduced processing speed, executive function, and attention, as reflected by longer completion times on the Stroop test (
Conclusions:
A later melatonin acrophase was associated with poorer cognitive performance in individuals with severe obesity undergoing evaluation for bariatric surgery. Larger longitudinal studies are needed to validate this association and determine whether changes in circadian timing are related to cognitive trajectories after bariatric surgery.