###HUMAN: how many patients during this year have received a sodium, urine test?, ###ASSISTANT: SELECT COUNT(DISTINCT admissions.subject_id) FROM admissions WHERE admissions.hadm_id IN (SELECT labevents.hadm_id FROM labevents WHERE labevents.itemid IN (SELECT d_labitems.itemid FROM d_labitems WHERE d_labitems.label = 'sodium, urine') AND DATETIME(labevents.charttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-0 year'))