Hematologic data predict survival in Mexican Mestizo people with Creutzfeldt-Jakob disease

Fabricio Cruz-López, School of Medicine, Benemérita Universidad Autónoma de Puebla, Heroica Puebla de Zaragoza, Puebla, Mexico; Department of Genetics, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Mexico City, Mexico; Department of Neurology and Psychiatry, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico; Undergraduate Medical Internship Program, Hospital Puebla, Puebla, Mexico
Miguel A. Ramírez-García, Department of Genetics, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Mexico City, Mexico
Petra Yescas-Gómez, Department of Genetics, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Mexico City, Mexico
Gustavo Reyes-Terán, Dirección Médica, Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, Mexico City, Mexico
Sergio I. Valdés-Ferrer, Department of Neurology and Psychiatry, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico; Secretaría de Salud, Gobierno de México, Mexico City, México; Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, New York, USA; Escuela de Medicina y Ciencias de la Salud, Tecnológico de Monterrey, Mexico City, Mexico

Objective: Creutzfeldt-Jakob disease (CJD) is a rare cause of rapidly progressive dementia due to the accumulation of misfolded prion proteins (PrPC) in the brain. Mortality is essentially universal within months to a few years after symptom onset. Here, we evaluated biomarkers derived from baseline complete blood counts (CBCs) in search of readily available predictors of disease progression using survival span as an outcome. Methods: We analyzed retrospective data derived from the baseline CBC from Mexican Mestizo individuals. We performed Spearman rho correlation to determine the association between survival time from disease onset with leukocyte and erythrocyte counts of people with CJD. We used Cox proportional hazard models to predict survival time, and log-rank tests to compare survival of subgroups. Results: We included 22 people with probable or definite CJD. Twelve (55%) were female. The mean age at diagnosis was 55 years (interquartile range: 25–85). Lower hemoglobin (r = –0.494, p = 0.019), hematocrit (r = –0.445, p = 0.037), and lymphocyte (r = –0.421, p = 0.050; log-rank test: χ2 = 3.7, p = 0.05) counts and higher neutrophils (r = 0.404, p = 0.061; log-rank test: χ2 = 5.7, p = 0.02) were associated with longer survival time. Conclusions: In the present study, we observed that common hematological values derived from a CBC were associated with survival span in people living with CJD. Those values support previous observations suggesting that the circulating availability of wild-type prion protein in blood cells is a limiting factor in the production of misfolded prion protein.

Keywords: Creutzfeldt-Jakob disease. Complete blood counts. Prion disease. Survival time. Biomarkers.