Standardization and reference intervals of platelet volume indices: Insight from the Brazilian longitudinal study of adult health (ELSA-BRASIL).

Platelet volume indices (PVI) are associated with hematological and non-hematological diseases, notably cardiovascular and cerebrovascular diseases. The establishment of PVI reference intervals (RIs) are essential to evaluate whether these indices are useful in clinical practice. Healthy-associated RIs have not yet been established for the Brazilian population. Here, we determined RIs of PVI for a health adult population, participants of the Brazilian Longitudinal Study of Adult Health ELSA-Brasil. A total of 580 individuals out of an initial sample of 3115 subjects constituted the healthy reference sample. To be part of the study, individuals had to fulfill the following criteria: blood count within 2 hours of collection, no use of continuous medication, self-rated health as good or very good, no reported diagnosis of diabetes and/or arterial hypertension, not smoking, lack of metabolic syndrome, body mass index (BMI) <30 kg/m(2), and platelet, hemoglobin, and creatinine beyond reference values. The RIs are mean platelet volume (MPV): 8.9-11.8 fL, platelet distribution width (PDW): 9.6-15.3 fL, platelet large cell ratio (P-LCR): 15.6-39.5%. These parameters were not significantly affected by age, gender, smoking, obesity, and alcohol abuse. However, significant differences were found among self-rated race/color groups. Standardization of measurement procedures and the establishment of healthy-associated PVI RIs are essential to be able to support clinical decision-making from laboratorial test results. This study at the baseline of the ELSA Brasil reported herein may contribute to future efforts aiming to evaluate whether PVI values are associated with clinical conditions in the Brazilian population.