The study seeks to characterize the clinical relevance of perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA) in immunosenescence, i.e., whether their emergence is a physiological manifestation of aging or a marker for latent pathology. Also it investigates the interaction between age-related neutrophil dysfunction, C-reactive protein (CRP) and body mass index (BMI). A cross-sectional sample of 200 healthy volunteers aged 20 to 60 years was employed. The volunteers were divided into 10-year age groups. Serum p-ANCA levels were measured by (ELISA), and CRP levels were measured by automated nephelometric immunoassay. The (BMI) was calculated using the anthropometric measurements. The results revealed that the increase in the concentrations of p-ANCA and CRP with age was highly significant (P=0.000) and the highest levels were found in the age group of 50-60 years for p-ANCA (32.74 ± 12.01ng/mL) and CRP (11.25 ± 3.83mg/L). Conversely, there was no significant difference in body mass index (BMI) across age groups (P = 0.282). Linear regression analysis revealed that older age was a strong predictor for higher levels of p-ANCA (R2 = 0.47, P = 0.000) and CRP (R2 = 0.56, P = 0.000). In addition, raised p-ANCA was a significant predictor of increased CRP levels (R2 = 0.32, P = 0.000). BMI was not associated with either immune marker. The findings imply that the development of systemic tissue inflammation and autoimmune manifestations is linked to biological immunosenescence regardless of adiposity and body mass. The results demonstrate that p-ANCA are an independent predictive biomarker of immunosenescence and chronic inflammation in healthy subjects and are not affected by body mass. The study shows that intrinsic immunosenescence due to declining peripheral immune tolerance mechanisms, rather than metabolic stress, is the major driver of age-related inflammaging, and provides novel scientific insights establishing this biomarker as a direct measure of aging irrespective of obesity.