Fig. 3: Changes in platelet contractile force are associated with the onset or resolution of bleeding symptoms in patients over time.

For several patients, we examined their platelets at multiple time points and observed that platelet forces as well as platelet counts can change over time. Moreover, these longitudinal changes in platelet contractile force were associated with the clinical bleeding score. Higher bleeding scores occurred when the patient’s platelet counts were <40 K/uL and platelet forces were <25 nN, and lower bleeding scores coincided with either an increase in platelet count, platelet force, or both. These data highlight the synergistic relationship between platelet count and platelet force. Additionally, leveraging a mixed mean model, and keeping platelet count constant while adjusting for patient and visit, we found that platelet contractile force is 10.79 nN less during instances where a patient’s bleeding score is between 2–4 versus when the bleeding score is either 0 or 1. Colored zones match those established in Fig. 2e. Source data are provided as a Source Data file.