Try
DECLARE @Events TABLE
(
EventId INT
,UserId INT
,EventName VARCHAR(100)
,EventDate DATETIME
)
INSERT INTO @Events
SELECT 1,1,'birth day', '1985-5-20'
UNION ALL
SELECT 2,2,'birth day', '1991-5-21'
UNION ALL
SELECT 3,3,'birth day', '1987-5-24'
UNION ALL
SELECT 4,4,'birth day', '1985-6-20'
UNION ALL
SELECT 5,5,'birth day', '1980-7-20'
SELECT *
FROM @Events
WHERE DATEADD(YEAR, DATEPART(YEAR, GETDATE()) - DATEPART(YEAR, EventDate), EventDate) >= GETDATE()