Associations Between Plasma Orexin-A Level and Constipation in Cognitive Impairment

Area of Science:

• Neurology
• Gastroenterology
• Biochemistry

Background:

• Constipation is a frequent and complex symptom in dementia patients.
• The precise causes of constipation in dementia remain unclear.
• Limited research has explored the connection between plasma orexin-A levels and constipation in dementia.

Purpose of the Study:

• To investigate the association between plasma orexin-A levels and constipation in individuals with cognitive impairment.
• To determine if orexin-A levels differ in patients with and without constipation across different dementia subtypes.

Main Methods:

• Plasma orexin-A levels and constipation status were assessed in patients with mild cognitive impairment (MCI), Alzheimer's disease (AD), and Lewy body dementia (LBD).
• Data were analyzed using logistic regression models to evaluate the relationship between orexin-A and constipation.
• The study included 21 MCI, 142 AD, and 57 LBD patients.

Main Results:

• Constipation was present in 21.36% of cognitive impairment patients, with a significantly higher prevalence in LBD (61.40%) compared to AD (5.63%) and MCI (19.05%).
• Patients with constipation exhibited lower plasma orexin-A levels compared to those without constipation (p < 0.001).
• Lower orexin-A levels were significantly associated with constipation occurrence in all cognitive impairment patients (OR = 0.151, p = 0.003), a finding more pronounced in LBD.

Conclusions:

• Decreased plasma orexin-A levels are strongly correlated with the presence of constipation in patients with cognitive impairment.
• Orexin-A appears to have a protective effect on the intestines and influences gastrointestinal symptoms in cognitive impairment.
• These findings highlight a potential therapeutic target for managing constipation in dementia.