['Detection of coronary artery calcification (CAC) has been proposed for population screening. It remains unknown whether such a strategy would result in unnecessary concern among participants. Therefore, we set out to assess whether CAC screening affects the psychological well-being of screening participants.', 'A random sample of 1825 middle-aged subjects (men and women, 50 or 60 y old) were invited for health screening. The European HeartScore was calculated, and a CAC score was measured using a cardiac computed tomography scanner. Therapeutic interventions as a result of the observations were at the discretion of the individual general practitioner. Before screening and at 6-month follow-up a depression test (Major Depression Inventory) was conducted, and the use of psychoactive medication was recorded.', 'A total of 1257 (69%) subjects agreed to participate. Because of known cardiovascular disease or diabetes mellitus, 88 persons were excluded. Of the remaining 1169, 47% were men, and one half were 50 years old. At 6-month follow-up, significant reductions were observed in the Major Depression Inventory score from 5.3 to 3.9 (P<0.0001) and in the prescription rates of psychoactive medication from 7.1% (83 of 1169) to 6.2% (72 of 1169) (P=0.003). The results were independent of sex, age, HeartScore, CAC Score, and changes in other medication.'] Does population screening for coronary artery calcification increase mental distress and the use of psychoactive medication?