To the Editor A recent study 1 found that mental stressinduced ischemia was significantly associated with an increased risk of cardiovascular events in patients with stable coronary heart disease. After adjustment for demographic, clinical, and psychological factors, the hazard ratio decreased but the effect remained statistically significant. In addition to mental stress, major depression is an important psychological risk factor for coronary heart disease. Furthermore, the close, bidirectional relationship between depression and coronary heart disease has been well established. 2 This study, 1 which only measured depression as the baseline psychological factor, was unable to identify new-onset depression prior to cardiovascular events. It is noteworthy that the baseline mean depression scores of the Myocardial Infarction and Mental Stress Study 2 (MIMS2) cohort 1 (13.7 and 12.1 in patients with and without mental stress–induced ischemia, respectively) were close to the threshold of mild depression, a score of 14 in the Beck Depression Inventory II. However, if the MIMS2 cohort’s depression scores were normally distributed, nearly half of these patients met the criteria for clinical depression at baseline.
