Case with Exist

declare @customerid INT
set @customerid=193546
select top 1 (CASE  WHEN exists(select * from table_name where P_ID = @customerid  and   StatusID <> 1)     THEN 'Main Account' WHEN exists(select * from table_name where C_Id = @customerid and statusid <> 1 )   THEN 'Sub-Account' ELSE '' END) as 'Merge Account'
 from table_name