Could the Combination of eGFR and mGPS Facilitate the Differential Diagnosis of Age-Related Renal Decline from Diseases? A Large Study on the Population of Western Sicily

The assessment of renal function is critical to diagnosing and managing renal age-related decline, disease (KD), and failure, which are prevalent in the elderly population. The glomerular filtration rate (GFR) is widely used as an indicator of kidney function, but its direct measurement is challenging, as are its age and gender caveats. This makes difficult the differential diagnosis between age-related physiological decline and KD and/or failure. Currently, the inflammation-based modified Glasgow prognostic score (mGPS) is emerging as a promising biomarker of several inflammatory acute/chronic diseases. In this study, the large variability of eGFR with age and gender was evaluated as the association of eGFR values with mGPS levels. A population of 57,449 adult participants (age ≥ 18 years) was enrolled. Appropriate circulating biomarkers were measured to detect eGFR and mGPS values. The data obtained demonstrated a significant decrease in eGFR in men vs. women across the four selected age classes (18-40, 40-60, 60-80, 80-100 years); eGFR classes were significantly associated with mGPS (p < 0.001), as were age classes and gender with mGPS categories. Accordingly, the percentage of people having an mGPS score = 2 significantly increased across the eGFR classes: with an 11% in the G1/eGFR class needed to achieve 44% in G5/eGFR. Thus, the combination of mGPS with eGFR could represent the best benchmark risk model for the differential diagnosis of kidney disease from the age-related eGFR reduction.