Abstract
Abstract Introduction Sleep is regulated by the microbiota-gut-brain axis, which plays a critical role in amyloid beta (Aβ) production and clearance; two key processes in the progression of sleep-related Alzheimer’s disease (SRAD). C-reactive protein (CRP) is an inflammatory biomarker correlated with Aβ levels in SRAD. Although Blacks are disproportionately affected by SRAD, a paucity of knowledge exists regarding effective early detection and prevention of this disease in this population. This study investigated the levels of CRP in Black participants with subjective Sleep apnea (SA) to determine what indicators or thresholds may serve as a risk predictive marker for Aβ blood biomarker screening for SRAD. Methods Blood from a total of 104 Blacks enrolled in two NIH-funded community-based sleep studies, ESSENTIAL and MOSAIC, was collected from January 2020 until October 2023. CRP levels were accessed according to clinical standards in ranges of normal or minor elevation, moderate elevation, marked elevation, and severe elevation. Frequency distributions and analyses were performed using SPSS29. Results Twenty-one participants self-reported an existing SA diagnosis; of which 19% had CRP levels at 0.3 - 1.0 mg/dL, 62% at 1.0 - 10.0 mg/dL, 19% at >10.0 mg/dL, and none at >50.0 mg/dL. Of the 83 participants without SA, 31% had CRP levels at 0.3 - 1.0 mg/dL, 61% at 1.0 - 10.0 mg/dL, 7% at >10.0 mg/dL, and 1% at >50.0 mg/dL. In total, 81% of participants with subjective SA had CRP levels above minor elevation, while 69% of participants without subjective SA had levels above minor elevation, showing a 10% difference in elevated CRP levels between both groups. These results suggest that SA can lead to greater levels of inflammation among Blacks. Conclusion A 10% difference in elevated CRP levels of participants with and without SA diagnosis may suggest that undiagnosed participants could be at risk for SA. Identifying factors that predict blood Aβ levels such as CRP may lead to a cost-effective, SRAD specific prescreening panel to identify patients at higher risk of SRAD, and aid risk stratification in Blacks. Future research is needed to further explore this area. Support (if any) R01AG067523, R01HL142066, and T32HL166609-02