if you are refering to the mean platelet volume
the normal is between 7 to 11.5. yours is on the higher side.
these are seen in certain conditions like May-Hegglin Anomaly Bernard-Soulier Disease, idiopathic thrombocytopenic purpura
it also means you may be in for increased risk of platelet aggregation and activation diseases like stroke
i would advise you to follow up with you physician regularly and get yourself treated with BP monitoring, test for your blood sugars too.
i hope i have answered your query.
take care and contact us back at HCM if you need further help