Reference intervals for platelet indices in seniors and frequency of abnormal results in a population-based setting: a comparison between directly and indirectly estimated reference intervals

Abstract

Abstract Objectives Mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT) possess diagnostic and prognostic capabilities in a variety of diseases. We aimed to establish reference intervals (RI) for platelet indices (PI) in seniors. Methods We established direct and indirect RI for MPV, PDW, and PCT in selected reference individuals aged 60 years and older. Abnormal PI were assessed in a population-based setting in the Principality of Liechtenstein, where 37.7% of the whole nation’s population aged 60 years and older had PI determined by hematology analyzers from Sysmex (Horgen, Switzerland). Results Among 689 female and 542 male participants, MPV and PDW did not exhibit age- and gender-specific differences, whereas PCT in females also displayed no age-specific differences. Age- and sex-independent RI were 9.3–12.5 fl for MPV and 10.1–16.7% for PDW, whereas the age-independent RI for PCT in women was 0.18–0.37. In males, age-specific RI for PCT were 0.16–0.30 (age 60–69), 0.15–0.33 (age 70–79), and 0.14–0.33 (age 80 and older). The population-based frequency of abnormal PI results was 0.8% (MPV), 1.1% (PDW), and 24.4% (PCT). Conclusions Applying novel RI for PI reveals that only approximately 1% of patients exhibit abnormal MPV and PDW. Abnormal PCT is observed much more frequently.