Table 3.

Association of nutritional status, as revealed by nutritional biomarkers, with outcomes and post-operative complications.

Authors Origin	Design Aim	n (Male/Female) Age, Mean ± SD (Years)	BMI (kg/m2) Biomarkers	Exclusion Criteria MN Definition Tool	Main Outcomes
Formiga Spain 2005 [41]	Prospective observational Relationship between nutritional status and complications	n 73 (12/61) 81.5 ± 7.1 years	Cholesterol 4.3 ± 1.1 mmol/L Albumin 30.6 ± 3.6 g/L TLC/mm3 1278 ± 463	Pathological or multiple fractures, terminally ill patients, surgery delayed >48 h or lipid-lowering drug MNA-SF <11	MNA-SF → 11 ± 0.5 MNA-SF not predict → nosocomial infections and pressure ulcers Albumin predict → nosocomial infections ↓ TLC years ↓ Albumin predict → pressure ulcers Barthel index ↔ Charlson comorbidity index r = −0.9 (p < 0.0001) Length of hospital stay = 16.4 days
Montero Spain 2007 [42]	Prospective cohort Relationship between malnutrition and recovery	n 110 (22/88) 81.4 ± 7.3 years	25(OH)vitD 10.8 ± 5.3 ng/ml TLC/ mm3 1545 ± 592 Albumin 32.6 ± 3.8 g/L Prealbumin 15.3 ± 4.7 mg/dL Cholesterol 160.5 ± 40.8 mg/dL Transferrin 195.9 ± 47.1 mg/dL	Pathologic or major trauma fractures Anthropometric and blood biomarkers	38.8% regained pre-fracture functional state Dementia ↔ ↓ functional recovery 25(OH)vit D <10 ng/ml ↔ ↓ pre-fracture functional state, with bedridden (1 year) and with no functional recovery (p < 0.05) Factors associated to bedridden (1 year) OR, 95%CI -pre-fracture functional status 10.02, 2.83–35.47 p < 0.01 -Caloric malnutrition 9.57 (2.18–42.84) p < 0.01 -Protein malnutrition 15.23 (1.36–1.70) p < 0.05
Baumgarten USA 2009 [37]	Prospective cohort Identify care settings associated with increased pressure ulcers risk	n 658 (152/506) 83.2 ± 6.6 years	23.8 ± 5.1 kg/m2	Fractures occurred during hospital stay Subjective Global Assessment (SGA)	Pressure ulcers at baseline ↔ ↑ severe illness, ↑ comorbidity, ↓ nutritional status, ↓cognitive status (p < 0.05) Albumin < 30 g/L: 31.5% Length of hospital stay 5.6 ± 2.8 (no pressure ulcers) vs. 6.6 ± 3.8 (pressure ulcers) (p < 0.001)
Drevet France 2014 [26]	Prospective observational Protein Energy Malnutrition prevalence	n 50 (15/35) 86.1 ± 4.4 years	22.6 ± 4.3 kg/m2	Road accident MNA	Prevalence of PEM was 28% (n 14) Mean hospital stay: PEM 21.9 ± 16.7 vs. 13.4 ± 6.7 in non-PEM (p = 0.012)
Goisser Germany 2015 [27]	Observational Relationship between nutritional status (MNA) and functional and clinical course	n 97 (20/77) 84 ± 5 years	NA	Terminal state, cancer-related pathologic fractures, cancer with acute radiation or chemotherapy MNA	Patients at risk for malnutrition and malnourished: -Baseline, ↑ comorbidities ↑ Charlson comorbidity index ↑ pressure ulcers ↓ cognitive status (p < 0.05) -All times, ↓ ADL score (p < 0.05) -68% did not regain pre-fracture ADL -18% did not regain pre-fracture mobility level (p = 0.02)
Bohl USA 2017 [21]	Retrospective Association between albumin with death, and postoperative complications	n 17,651 (12,595/5056) 84.4 ± 7.2 years	24.6 ± 5.6 kg/m2 Albumin 35 ± 5 g/dL	Preoperative serum albumin concentration not available Albumin concentration	18.5% had BMI < 20 kg/m2 Patients with hypoalbuminemia had higher rates: -of death (RR 1.52. 95%CI 1.37–1.70. p < 0.001) -of sepsis (RR 1.92. 95%CI 1.36–2.72. p < 0.001) -of longer legnth of hospital stay, 5.7 ± 4.7 vs. 5.0 ± 3.9 days (p < 0.001)
Helminen Finland 2017 [31]	Prospective Prognostic significance of MNA and albumin	n 594 (169/425) 84 years	24.9 kg/m2 Albumin 33.5 g/L	Pathological or periprosthetic fractures, institutionalization, prefecture inability to walk MNA-SF	All nutritional measures were significantly associated with mortality Being at risk for malnutrition or being malnourished were significantly associated with impaired mobility at 4 months and 1 year
Mazzola Italy 2017 [32]	Prospective If nutritional status predict postoperative delirium	n 415 (104/309) 84 ± 6.6 years	NA Albumin 33 ± 5.4 g/L	Nonoperative approach and preoperative delirium MNA-SF	Risk to develop postoperative delirium: -at risk for malnutrition: OR 2.42, 95%CI 1.29–4.53 -malnourished: OR 2.98, 95%CI 1.43–6.19
Inoue Japan 2017 [30]	Prospective Relationship between nutritional status and functional recovery	204 (39/165) 82.7 ± 9.2 years	20.2 ± 2.5 kg/m2 Albumin 36 ± 9 g/L	Terminal disease, chronic liver disease, pre-fracture ambulation difficulty, no weight-bearing, discontinued postoperative rehabilitation MNA-SF	Well-nourished had higher motor-FIM score at discharge Motor-FIM at discharge was significant associated with MNA-SF

ADL: activities of daily living; BMI: body mass index; FIM: functional Independence Measure; HF: hip fracture; MNA: Mini Nutritional Assessment; PEM: protein energy malnutrition; OR: odd-ratio; 95%CI: 95% confidence interval. ↔: correlation.