Elevated Urinary AD7c-NTP Levels in Older Adults with Hypertension and Cognitive Impairment

Background: Hypertension, a common chronic disease, is associated with cognitive impairment. Cognitive impairment, especially Alzheimer's disease (AD), seriously affects older adults' quality of life and aggravates the burden of disease on society and families. Elevated Alzheimer-associated neuronal thread protein (AD7c-NTP) has been observed in the urine of patients with AD and mild cognitive impairment; however, it is not clear whether this protein can be used as a biomarker for cognitive impairment in older hypertensive patients. Objective: To explore the value of urinary AD7c-NTP, and the association of urinary AD7c-NTP with cognitive function in older hypertensive patients. Methods: This was a cross-sectional study. In total, 134 hypertensive patients aged >= 60 years were divided into two groups: Lower Cognitive Function group (LCF group, n = 89) and Normal Control group (NC group, n= 45) based on the Montreal Cognitive Assessment (MoCA). Urinary AD7c-NTP, blood glucose, serum insulin, superoxide dismutase (SOD) and malondialdehyde (MDA) levels were measured. Results: Urinary AD7c-NTP level was significantly higher in the LCF group than in the NC group [0.48 (0.21-1.00) versus 0.25 (0.04-0.44) ng/ml, p < 0.001]. The LCF group had lower SOD level [(43.07 +/- 23.74) versus (53.12 +/- 25.80) U/ml, p = 0.026] and higher homeostasis model assessment of insulin resistance (HOMA-IR) [7.17 (3.74-13.94) versus 6.01 (3.78-7.43), p = 0.033] than the NC group. Urinary AD7c-NTP level was associated with MoCA score and HOMA-IR but not with SOD, MDA, blood glucose, and insulin. Conclusion: The level of urinary AD7c-NTP is elevated in older hypertensive patients with lower cognitive function, and insulin resistance may be involved in the process.