I-Thrombocytopenic purpura ingathinta bonke ubudala nabo bonke ubulili. Kwabantu abadala abasebasha, ithinta abesifazane kakhulu kunabesilisa. Ngakolunye uhlangothi, eminyakeni yobudala engama-50, amadoda athinteka kakhulu kunabesifazane.

I-Rheumatoid purpura ithinta kakhulu izingane kanye kanye nabantu abadala abasebasha, iningi lamacala aneminyaka emi-5 ubudala. Abafana bazothinteka kakhulu kunamantombazane.