Nutrition-related clinical laboratory indicators in perioperative management of geriatric hip fractures: a narrative review from risk stratification to precision intervention

Figure 1. Hierarchical spectrum of nutrition-related laboratory biomarkers in geriatric hip fracture, organized by increasing complexity across four tiers. Tier 1 encompasses classical protein nutritional markers (albumin, prealbumin, IGF-1) with established prognostic associations. Tier 2 includes simple inflammatory-nutritional ratios derived from routine laboratory panels. Tier 3 comprises comprehensive multi-parameter scoring systems integrating nutritional and inflammatory data. Tier 4 represents the frontier of machine learning–integrated predictive models and emerging proteomic/molecular biomarkers. Key predictive associations and effect sizes are indicated for each biomarker. This framework guides clinicians in selecting appropriate indicators based on clinical context, prognostic needs, and available resources. POP, postoperative pneumonia; POD, postoperative delirium; AKI, acute kidney injury; IGF-1, insulin-like growth factor 1; GAR, glucose-to-albumin ratio; CAR, CRP-to-albumin ratio; AGR, albumin-to-globulin ratio; DAR, D-dimer-to-albumin ratio; CLR, C-reactive protein-to-lymphocyte ratio; RDW, red cell distribution width; PNI, Prognostic Nutritional Index; CONUT, Controlling…

Figure 2. Pathophysiological framework of the malnutrition–inflammation–osteosarcopenia nexus in geriatric hip fracture. The diagram illustrates how the acute catabolic response triggered by hip fracture, characterized by systemic inflammation, enhanced catabolism, and nutritional depletion, drives the interconnected triad of malnutrition, sarcopenia, and osteoporosis (osteosarcopenia). Bidirectional arrows denote mutually reinforcing pathological interactions. Key laboratory biomarkers associated with each component are indicated. Evidence-based therapeutic targets and their components are shown at the bottom. CRP, C-reactive protein; IL-6, interleukin-6; TNF-α, tumor necrosis factor alpha; IGF-1, insulin-like growth factor 1; β-CTX, β-C-terminal telopeptide of type I collagen; PINP, N-terminal propeptide of type I procollagen; GDF-15, growth differentiation factor 15; IGFBP-2, insulin-like growth factor binding protein 2; FGF-23, fibroblast growth factor 23; PNI, Prognostic Nutritional Index; GNRI, Geriatric Nutritional Risk Index; CONUT, Controlling Nutritional Status; HALP, Hemoglobin, Albumin, Lymphocyte, and Platelet; AKI, acute kidney injury; SSI, surgical site infection; DVT, deep…

Figure 3. Proposed closed-loop precision management pathway integrating nutrition-related laboratory indicators into perioperative care of geriatric hip fracture patients. The pathway comprises four sequential steps: (Step 1) rapid admission screening using a core laboratory panel and validated tools with predefined trigger thresholds; (Step 2) complication-specific risk stratification deploying targeted biomarker combinations for pneumonia, delirium, venous thromboembolism, acute kidney injury, and surgical site infection; (Step 3) precision multidisciplinary intervention guided by identified risk profiles, encompassing nutritional support and integrated care bundles; and (Step 4) dynamic postoperative reassessment at defined time points with laboratory and functional monitoring. The closed-loop arrow (right) indicates that reassessment findings continuously feed back into re-stratification and intervention modification. Note this proposed clinical decision-making pathway and its specified indicator thresholds are currently conceptual and hypothetical, serving as a framework for future research that strictly mandates rigorous prospective validation in clinical settings. CRP, C-reactive…