Caffeine Intake and Depressive Symptoms among Healthcare Workers: The Role of Stress and Sleep Quality

Caffeine is widely consumed among healthcare workers (HCWs) as a coping mechanism for occupational demands and may influence depressive symptoms. This study investigated this relationship after adjustment for perceived stress and sleep quality. In this cross-sectional study on licensed HCWs at a tertiary hospital in Jeddah, Saudi Arabia, habitual caffeine intake was assessed using a validated caffeine food frequency questionnaire. Depressive symptoms were assessed using Patient Health Questionnaire (PHQ-9), with clinically significant depressive symptoms defined as PHQ-9 ≥ 10. Perceived stress and sleep quality were measured. Logistic and linear regression models evaluated the associations with PHQ-9 ≥ 10 and PHQ-9 score respectively. Among 298 HCWs (mean age 37.5 years; 66.1% women), 18.5% had PHQ-9 ≥ 10. Mean caffeine intake was 216 mg/day (median 125 mg/day). HCWs with PHQ-9 ≥ 10 reported a higher caffeine intake than those without (Mean 282 vs. 201 mg/day and median 169 vs. 114 mg/day; p  = 0.038). Caffeine intake was significantly associated with PHQ-9 score but not with PHQ-9 ≥ 10 after full adjustment (β = 0.331; p  = 0.014 per twofold increase). Perceived stress and poorer sleep quality were independently associated with PHQ-9 ≥ 10. Higher caffeine intake may reflect response to occupational strains rather than a primary depression risk driver.