index – How can I optimize this MySql Select query?

I have the following query executed every 1 minute in a cron job

SELECT ACCOUNT (*)
FROM `Orders` AS` or`
WHERE (`o``OrderStatus` = 0) AND (` o` `CreatedAt`> DATE_ADD (UTC_TIMESTAMP (), INTERVAL -1.0 minute))

Should I add index in the Order status Y Created in columns, and if so, what kind of indexes?