(HM09) Platelet Function Analysis Using the PFA-200 in Geriatric Dogs

Abstract:
Background - Platelets are essential for primary hemostasis, and their function can be influenced by various factors, including aging. While human studies often show increased platelet activation with age, leading to a prothrombotic state, the effects of aging on platelet function in dogs remain less clear.
Objectives - This study aims to compare and evaluate age-related changes in platelet function in dogs using the Platelet Function Analyzer-200 (PFA-200). 
Animals - Eighty healthy dogs weighing less than 15kg were divided into a geriatric group (≥10 years old, n=48) and a control group (< 10 years old, n=32).
Methods - Platelet function was assessed using collagen/adenosine diphosphate (COL/ADP) and collagen/epinephrine (COL/EPI) cartridges. Platelet counts were also measured.
Results - Compared to the control group, geriatric dogs exhibited significantly prolonged closure times for both COL/ADP and COL/EPI, with p-values of 0.002 and 0.003, respectively. Platelet counts were also significantly higher in the geriatric group than in controls. Pearson correlation analysis showed significant positive correlations between age and closure times for COL/ADP and COL/EPI, also platelet count. Closure times did not differ significantly based on weight, sex, or breed.
Conclusions - Our study suggests that as dogs age, their platelet function tends to decline, as supported by prolonged closure times and increased platelet counts. Interestingly, these results differ from human studies, where aging usually makes platelets more reactive. Understanding these species-specific variations is crucial for improving clinical care in geriatric canine patients.