Risk Analysis of Falls in Patients Who Underwent Allogeneic Hematopoietic Stem Cell Transplantation

[Backgound] In spite of various efforts to prevent falls, it remains a major problem in safety-managements in acute care hospitals such as those with hematopoietic stem cell transplantation (HSCT) ward. Although analyses of fall risks have been reported in other fields, studies on falls in the HSCT setting are scarce. In this study, we retrospectively searched for risk factors of falls in our HSCT patients, focusing on the differences of the fall risks in pre- and post-engraftment periods. [Methods] 77 consecutive patients who received allogeneic HSCT on our ward from Apr. 2010 to Mar. 2011 were retrospectively reviewed for the following 1) – 9) information based on the medical chart: 1) age/sex, 2) incident of fall, 3) location and circumstance surrounding each incident, 4) date of the fall, and medications at that time, 5) time of the fall, 6) cause of the fall, 7) scores of Functional Independence Measure (FIM), 8) patient’s response to the fall, and 9) result of the Picture-Frustration Study (P-F study). [Results] Among 77 patients, 35 patients experienced at least one incident of falls (fallers). The remaining 42 patients were allocated as a control group (nonfallers). The main location of falls was a corridor, and the main situation was going to the toilet. Hypnotics and anxiolytics were prescribed more frequently in fallers than in nonfallers both in the pre- and post-engraftment periods. Opioids were prescribed more frequently in fallers only in the post-engraftment period. Whereas pre-engraftment falls tend to occur from midnight to early in the morning, post-engraftment falls tend to occur in the day time. Whereas the main symptom of the pre-engraftment falls was dizziness, the symptom of the post-engraftment falls was sudden listlessness of the knees. As regards muscle weakness, whereas the FIM scores of fallers and nonfallers were not different in the pre-engraftment period, the FIM score of fallers was significantly lower than that of nonfallers in the post-engraftment period. Finally, the P-F study revealed that fallers tend to be more modest and patient than nonfallers. [Conclusions] The results suggest that the pre-engraftment falls be induced by drugs such as hypnotics and anxiolytics. On the other hand, insidious muscle weakness may be a key risk factor for the post-engraftment falls in addition to the use of painkillers. Furthermore, patients’ character such as modesty and patience might affect the tendency of falling.