Abstract
Background Fatigue presents an important challenge for patients discharged from intensive care units (ICUs). Despite its importance, data on the prevalence and clinical impact of post-ICU fatigue remain limited. In particular, the proportion of patients in clinical settings in Japan who find fatigue distressing, as well as the associations between fatigue, risk factors, and self-rated health, have not been fully explored using validated fatigue measures. Therefore, this study aimed to assess the prevalence of fatigue, identify its associated risk factors, and examine the relationship between fatigue and self-rated health status six months after ICU discharge in Japan. Methods This single-center, ambidirectional cohort study administered a survey to patients aged ≥18 years, six months after ICU discharge, to assess fatigue and self-rated health. Retrospective data were also collected from patients' medical records during hospitalization. Fatigue prevalence was the primary endpoint, measured using the cutoff value of the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) scale. Logistic regression analysis was performed to identify risk factors for fatigue. Locally weighted scatterplot smoothing (LOWESS) plots were generated with FACIT-F scale scores, and the association between fatigue and EuroQol 5 Dimensions 5-Level Visual Analog Scale (EQ-VAS) was analyzed. Results Questionnaires were sent to 87 patients, of whom 81 (93.1%) responded. Eight patients (9.9%) with missing FACIT-F scores were excluded, leaving 73 patients for analysis. The median (interquartile range) age of eligible patients was 74 (63-81) years, and 33 patients (45%) were male. Forty-six patients (63%) reported fatigue. Multivariate analysis identified a higher body mass index (BMI) at ICU admission as an independent risk factor for fatigue (odds ratio (OR) = 1.195; 95% confidence interval (CI) 1.018-1.447; p < 0.05). EQ-VAS scores were significantly lower in the fatigue group (OR 72.5, 95% CI 60-83.8 vs. OR 90, 95% CI 80-90; p < 0.01). Conclusion This study found that many patients in Japanese ICUs experience fatigue, even when disease severity is low. Additionally, BMI at ICU admission was identified as an independent risk factor for fatigue six months after ICU discharge. Regular follow-up on fatigue after ICU discharge is essential for improving long-term outcomes.