Income Differences in the Association Between Medical-Preventive Integration KAP and Depressive Symptoms: A Cross-Sectional Study Among Chinese Healthcare Workers

Objective: To examine the relationship between Knowledge, Attitude, and Practice (KAP) regarding medical-preventive integration and depressive symptoms among Chinese healthcare workers, placing special emphasis on the moderating association of monthly income, while adjusting for work stress as an important covariate. Methods: This study analyzed data from a 2024 cross-sectional survey conducted in two provinces of China, encompassing a total of 5908 healthcare workers. Descriptive statistics were employed to examine the demographic and professional characteristics of the participants. Multiple linear regression was used to investigate the direct associations between medical-preventive integration knowledge, attitude, practice, and depressive symptoms. Furthermore, while moderation analysis was used to assess the interactive association of monthly income in this relationship. Results: The findings demonstrate a significant link between medical-preventive integration knowledge, attitude, and practice (KAP) and depressive symptoms, with knowledge (B = −0.074, 95% CI = −0.134, −0.015) and attitude (B = −0.467, 95% CI = −0.531, −0.403) showing a negative association with depressive symptoms, while practice (B = 0.648, 95% CI = 0.527, 0.770) was positively associated with depressive symptoms. Work stress was positively associated with both practice engagement and depressive symptoms. Additionally, higher income amplified the inverse associations of knowledge (B = −0.040, 95% CI = −0.061, −0.019) and attitude (B = −0.028, 95% CI = −0.046, −0.012) with depressive symptoms and strengthened the positive association between practice (B = 0.066, 95% CI = 0.022, 0.109) and depressive symptoms, as indicated by significant interaction association. Conclusions: Our findings highlight a complex link between KAP patterns and depressive symptoms, with work stress as a significant correlate and income as a moderator. Healthcare workers with higher income and those with supportive knowledge and attitude show a lower probability of experiencing depressive symptoms, whereas greater behavioral engagement is associated with increased depressive symptoms, particularly among those with higher income. There is an urgent requirement to establish targeted interventions, optimizing support and resources, to decrease susceptibility to depressive symptoms among healthcare workers, particularly those with higher income and higher levels of behavioral engagement.