Family coping profiles in patients with chronic heart failure: a latent profile analysis.

Increasing life expectancy and the progressive growth of the elderly population have led to a rise in the prevalence of age-related cognitive impairment and neurodegenerative disorders, including Alzheimer’s disease and Parkinson’s disease. Early diagnosis and prediction of disease progression remain challenging, as neuronal dysfunction and the initial pathological processes often precede the onset of clinical manifestations, while early symptoms are frequently non-specific. Therefore, the identification and validation of accessible, minimally invasive biomarkers capable of detecting pathological processes at the preclinical stage, predicting the rate of cognitive decline, and assessing the efficacy of potential neuroprotective therapies are of considerable importance. Peripheral biomarkers measurable in serum or plasma represent the most practical option for routine clinical use; however, reliable peripheral biomarkers of neurodegeneration remain limited. Over the past decade, accumulating evidence has linked alterations in the expression of neurotrophic factors, particularly brain-derived neurotrophic factor (BDNF), with the development of neurodegenerative processes (; ). BDNF plays a critical role in the development of both the central and peripheral nervous systems and is essential for neuronal maturation, survival, and functional maintenance. In addition, BDNF promotes synaptogenesis and regulates synaptic transmission and plasticity (). Alterations in BDNF signaling pathways and changes in its concentration affect memory and cognitive function in a range of age-related cognitive disorders, including Alzheimer’s disease and mild cognitive impairment (). However, evidence regarding the relationship between peripheral BDNF levels and neurodegenerative diseases remains inconsistent. Several studies have reported reduced peripheral BDNF concentrations in patients with Alzheimer’s disease and mild cognitive impairment compared with healthy controls (; ), whereas others have demonstrated elevated BDNF levels in patients with Alzheimer’s disease ().