Aim. This study examined the effect of white noise on depression of patients in the Cardiac Care Unit (CCU).

Background. Many patients with cardiovascular disease are susceptible to experience depression after admission in Cardiac Care Unit (CCU). Depression can influence patients' recovery.

Method. This was a quasi-experimental study conducted in Shaheed Rajaei Cardiovascular Center, Tehran in 2014. Ninety patients admitted to the cardiac care unit were recruited in the study based on convenience sampling and divided into experimental and control group (45 patients in each group). Depression was measured for 3 consecutive days by depression subscale of DASS-21 questionnaire. In the experimental group, white noise with an intensity of 50 to 60 decibels was played for 30 minutes. Data were analyzed by SPSS , version 17, using independent t-test, paired t-test and chi-square test.

Findings. In control group, no statically significant difference was observed between mean scores of depression, before and after intervention (4.12±4.35 and 3.52±3.74, respectively; p=0.05). In the experimental group, the difference between mean scores of depression, before and after intervention was statistically significant (4.81±4.47 and 3.93±4.48, respectively; p=0.02).

Conclusion. According to the findings, white noise can leads to a significant reduction in depression. This intervention can be used as a simple and low-cost non-pharmacological care for these patients.