Variability of Nutritional Status During Hematopoietic Stem Cell Transplantation and Its Association With Clinical Outcomes: An Ambispective Observational Study From India.

Background Nutritional deterioration is frequent during hematopoietic stem cell transplant (HSCT), but Indian data detailing serial weight and calorie intake changes and their outcome associations remain limited. This study evaluated peri-transplant nutritional variability among HSCT recipients at an Indian tertiary care center, exploring relationships with infectious morbidity, hospitalization, quality of life, nonrelapse mortality, and survival.  Methods We conducted an ambispective observational cohort study of 50 HSCT recipients (26 prospective and 24 retrospective) treated between December 2021 and October 2023. Serial nutritional assessments included weight, body mass index or pediatric anthropometry, calorie intake, and biochemical parameters at baseline and post-transplant time points. Outcomes evaluated were mucositis, acute graft-versus-host disease, infections (bacterial, viral, and fungal), quality of life, length of hospital stay, non-relapse mortality, and overall survival. Statistical evaluations utilized repeated-measures and univariable analyses, Kaplan-Meier survival estimations, and a linear mixed-effects model for post-transplant weight trajectories. Results The median age was 19.5 years (range: 2-64), with 29 males. Transplants were allogeneic (n = 36) or autologous (n = 14), and baseline nutritional abnormalities (under/overnutrition) were present in 19 patients. Mean weight change from admission progressed from -1.80% at day 0 to -7.65% at day +30 and -7.60% at day +60. Mean calorie intake declined most sharply by day +7 (-29.0%), improving gradually thereafter. At day +60, mean weight loss was greater in patients with viral infections (-14.7% vs. -5.4%; p = 0.03) and hospital stays > 36 days (-14.6% vs. -5.3%; p = 0.025). Reduced calorie intake was associated with bacterial infections at days 0, +21, and +60. Quality-of-life scores declined post-transplant, partially recovering by day +60, and day +100 non-relapse mortality was 16%. At a median 340-day follow-up, overall survival was 68%, and the estimated one-year overall survival probability was 72% (95% confidence interval, 60%-82%). In the linear mixed-effects model, age, sex, and diagnosis did not significantly predict weight change. Marginal (0.066) and conditional (0.680) R-squared values showed repeated-measures structures captured greater observed variability than fixed demographic/diagnostic covariates. Conclusion Peri-transplant nutritional decline was common in this Indian HSCT cohort. Weight loss continued beyond maximal calorie reduction, associating with adverse outcomes like viral infections and prolonged hospitalization, whereas reduced calorie intake correlated with bacterial infections. These findings support structured nutritional assessments, early dietetic involvement, and proactive nutritional support in routine transplant care. Larger prospective multicenter studies are needed to confirm associations and define standardized nutrition-focused HSCT interventions.