Caffeine Intake, depressive symptoms, perceived stress and sleep quality in healthcare workers: a cross-sectional study

Caffeine is widely consumed among healthcare workers (HCWs) to cope with occupational demands and may be related to depressive symptoms. This study examined that relationship after adjustment for perceived stress, sleep quality and relevant demographic and lifestyle covariates. Among 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 the Patient Health Questionnaire (PHQ-9), with clinically significant symptoms defined as PHQ-9 ≥ 10. Perceived stress and sleep quality were measured. Logistic and linear regression 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. Median caffeine intake was 125 mg/day (mean 216 mg/day). HCWs with PHQ-9 ≥ 10 reported higher caffeine intake than those without (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 a response to occupational strain rather than being independently associated with depressive symptoms.