Association Between Screen Exposure and Insomnia Among Patients With Breast Cancer: Cross-Sectional Study.

Background: Insomnia burdens patients with breast cancer, exceeding its prevalence in other malignancies. While excessive screen time is known to disrupt sleep in children and adolescents, its impact on patients with breast cancer remains underexplored, particularly regarding how perceived stigma may modify screen-related sleep disruption. Objective: This study aimed to investigate the associations between both objectively measured total daily screen time and self-reported presleep screen time and insomnia in patients with breast cancer while assessing the effect measure modification by perceived stigma. Methods: This cross-sectional study recruited 778 patients with breast cancer from the Department of Breast Surgery, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, between August 1, 2023, and February 20, 2024. Total daily and presleep screen time were assessed as exposures, whereas insomnia, diagnosed using a standardized clinical assessment based on Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, criteria, served as the main outcome. Multivariable logistic regression models were used to estimate odds ratios and 95% CIs for the associations between screen time and insomnia using hierarchical adjustment across 3 models. Results: Of the 240 participants with complete data on total daily screen time (mean age 51.82, SD 10.62 years), 186 (77.5%) were diagnosed with insomnia. Of the 644 participants with data on presleep screen time (mean age 53.46, SD 10.76 years), 419 (65.1%) met the criteria for insomnia. The median total daily screen time was 334.00 (IQR 232.50-440.25) minutes, whereas the median presleep screen time was 30.00 (IQR 10.00-120.00) minutes. Each 30-minute increase in total daily and presleep screen time was associated with higher odds of insomnia (adjusted odds ratio [aOR] 1.14, 95% CI 1.05-1.23, and aOR 1.41, 95% CI 1.26-1.57, respectively). High exposure was associated with 2.46-fold (more than the median [334 minutes per day]) and 3.22-fold (more than the median [30 minutes]) higher odds of insomnia. Stratified by perceived stigma, participants with both high daily screen time and high stigma had the highest odds of insomnia (aOR 4.53, 95% CI 1.42-14.49). A similar pattern was observed for high presleep screen time and high stigma (aOR 2.59, 95% CI 1.54-4.37). However, effect measure modification was not significant on either the multiplicative or additive scale. Conclusions: This cross-sectional study revealed associations between screen time exposure and insomnia in patients with breast cancer, with more consistent findings for presleep screen time. Findings for total daily screen time should be interpreted cautiously because of extensive missing objective screen time data. These findings support further longitudinal studies and suggest that reducing presleep screen exposure may be considered in supportive oncology care.