Coagulation Abnormalities in Light Chain Amyloidosis

Objective: To assess the prevalence of coagulation abnormalities in patients with systemic light chain (AL) amyloidosis and their association with disease-related characteristics, disease progression, and survival. Patients and Methods: This is a retrospective study of patients with AL amyloidosis seen at Mayo Clinic, Rochester, Minnesota, from January 1, 2006, to December 31, 2015. We studied the association between abnormal coagulation parameters and baseline characteristics and their association with survival outcomes. Results: The study included 411 patients. Abnormalities at diagnosis included prolonged clotting times and coagulation factor deficiencies; prolonged prothrombin time (PT) and factor X (FX) deficiency were found in 19% (73 of 390) and 43% (177 of 411) of patients, respectively. The FX deficiency was associated with higher Mayo stage, involvement of more than 1 organ, liver and cardiac involvement, and greater than 10% bone marrow plasma cells. On univariate analysis, the risk for disease progression or death was higher in patients with abnormal values for PT and factor V, factor VII (FVII), FX, and factor XII compared with those with normal values. Prolonged PT and FVII and FX deficiencies were independent predictors of death after adjusting for Mayo stage and more than 1 organ involvement. Only 106 patients had repeat testing after treatment; no clear relationship was found between treatment response and changes in coagulation parameters. Conclusion: Coagulation abnormalities occur in a significant proportion of patients with AL amyloidosis and are associated with advanced disease and inferior outcomes. Larger studies are needed to establish whether a relationship exists between treatment response and improvement in individual parameters.