Sex Differences in the Associations of Non-Medical Use of Prescription Drugs with Depressive and Anxiety Symptoms among Undergraduates in China.

Background: Non-medical use of prescription drugs (NMUPD) and their association with depression and anxiety are becoming global concerns. Biological sex may introduce differential exposure to NMUPD or depressive/ anxiety symptoms. However, few studies have investigated the potential sex differences in the associations of NMUPD with depressive/anxiety symptoms.Methods: Data were drawn from the 2019 School-based Chinese College Students Health Survey. A total of 30,039 undergraduates (mean age: 19.8 [SD: 1.3] years) from sixty universities/colleges in China completed standard questionnaires and were included in the study (response rate: 97.7 %).Results: In the final adjusted model, non-medical use of opioids (experimenters: beta = 1.10, [95 % CI, 0.62 to 1.57]) or sedatives (frequent users: beta = 2.98, [95 % CI, 0.70 to 5.26]) was associated with depressive symptoms, while non-medical use of opioids (frequent users: beta = 1.37, [95 % CI, 0.32 to 2.42]) or sedatives (frequent users: beta = 1.19, [95 % CI, 0.35 to 2.03]) was also associated with anxiety symptoms. Sex-stratified analyses indicated that lifetime opioids misuse was associated with depressive symptoms in both sexes but with anxiety symptoms only in males (beta = 0.39, [95 % CI, 0.09 to 0.70]). The association of lifetime sedative misuse with depressive symptoms was greater in males, while the significant association with anxiety symptoms remained only in female (beta = 0.52, [95 % CI, 0.14 to 0.91]).Limitations: Causal inference cannot be made due to the cross-sectional nature of the data. Conclusions: Our study suggests NMUPD is associated with depressive and anxiety symptoms among Chinese undergraduates, and the associations may differ by sex.