try this
SELECT
SUBSTRING(st.text, (qs.statement_start_offset/2)+1,
((CASE qs.statement_end_offset
WHEN -1 THEN DATALENGTH(st.text)
ELSE qs.statement_end_offset
END - qs.statement_start_offset)/2) + 1) AS statement_text, dbid, pa.value [User ID],
SUSER_NAME(cast(pa.value as int)), USER_NAME(cast(pa.value as int))
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS st
OUTER APPLY sys.dm_exec_plan_attributes(plan_handle) pa
WHERE pa.attribute like '%user_id%'