Pre-transplant nutritional status and hospitalization risk in outpatient hematopoietic stem cell transplantation: A prospective study using the patient-generated subjective global assessment

Abstract Background Hematopoietic stem cell transplantation (HSCT) is a complex process that can impair nutritional status, leading to a decrease in body fat and lean mass due to the conditioning regimen, prior line of therapy, immunosuppressive therapy, and metabolic alterations that affect appetite and food intake.Nutritional status is critical and affects outcomes in patients undergoing HSCT. Biomarkers such as albumin and prealbumin have been used, but they are affected by inflammation. On the other hand, bioelectrical impedance (BI) provides objective data on body composition, and instruments such as the Patient-Generated Subjective Global Assessment (PG-SGA) can identify patients with nutritional risk.Our center operates a fully ambulatory HSCT program, which makes the early identification of nutritional risk particularly relevant. Understanding the impact of nutritional status in the context of outpatient HSCT is essential, as it may influence the risk of complications, unplanned hospitalizations, and overall outcomes. Methods A prospective study at our outpatient HSCT center included patients undergoing HSCT, aged 18–75 years. Before conditioning, all participants underwent a nutritional evaluation by a licensed nutritionist, which included BI analysis and the PG-SGA. The evaluation was repeated at day +30 (±10) post-transplant. The primary objective was to assess the cumulative incidence of hospitalization according to pre-transplant nutritional status as defined by the PG-SGA. Secondary objectives included incidence of infection, non-relapse mortality (NRM), overall survival (OS), and relapse-free survival (RFS). Cumulative incidence functions were used to estimate hospitalization, infection, and NRM, accounting for competing risks (death for hospitalization/infection and relapse for NRM). Fine-Gray regression was used to estimate subdistribution hazard ratios (HRs). OS and RFS were estimated using the Kaplan-Meier method, and Cox proportional hazards models were used to derive hazard ratios. A p-value < 0.05 was considered statistically significant. Results A total of 85 patients have been enrolled, 38% (n = 32) females and 62% (n=53) males. The median age was 45 years (range: 18-72). Most patients had a 0-1 ECOG (98%, n = 83), an HCT-CI of 0 (76%, n = 65), and were enrolled after a median of 2 (range: 1-3) lines of therapy. The most common transplant indication was acute myeloid leukemia (27%, n = 23), followed by acute lymphoid leukemia (26%, n = 22) and multiple myeloma in third (24%, n=25%). Autologous transplantation was the most common type of HCT (42%, n = 36), followed by haploidentical (36%, n = 31) and matched sibling (21%, n=18). Most patients (66%, n = 56) were classified as “well nourished” per the pre-transplant PG-SGA and the remaining as “moderate or suspected malnutrition”. The 100-day cumulative incidence of hospitalization was significantly higher in malnourished patients compared to well-nourished ones (76.9% vs. 41.4%; p = 0.015). In Fine-Gray regression, baseline malnutrition was associated with an increased risk of hospitalization (subdistribution HR 2.24; 95% CI, 1.09–4.60; p = 0.029). The 100-day cumulative incidence of infection was higher among malnourished patients (61% vs 34%, p = 0.03, HR 2.01, 95%CI 1.06-3.81). Significant differences were also observed in 100-day NRM (13% vs. 0%, p = 0.02). 1-year OS was superior in well-nourished patients (91.5% vs 62%, p = 0.004, HR 4.73 95%CI 1.3-16.2) as well as 1-year RFS (91.5% vs 62%, p = 0.006, HR 4.73 95%CI 1.3-16.2). Changes in body composition were assessed at day +30 post-transplant, comparing those who required hospitalization (N = 39) with those who did not (N = 46). Hospitalized patients had a greater decrease in body fat percentage (30% [26–37] vs. 34% [30–41]) and visceral fat (9.0 [7.0–15.0] vs. 13.0 [9.0–16.0]), compared with non-hospitalized patients. Among patients classified as “well nourished” in the pre-transplant assessment, 53% were re-classified as “moderate or suspected malnutrition” in the post-transplant assessment, and 1.9% as “severely malnourished”. Conclusions Pre-transplant nutritional status, determined by PG-SGA, showed that non well-nourished patients had higher incidence of hospitalization and infections in patients undergoing outpatient HSCT, emphasizing that early nutritional risk assessment and targeted interventions are not optional, but essential components of care.