Sleep quality in medical students: Any relationship with fatigue severity?

• First time the relationship between poor sleep quality and fatigue was assessed in interns. • 94.4% of interns with poor sleep had moderate to high fatigue risk. • 79.4% of interns reported poor sleep quality assessed by PSQI. • Poor sleep quality and fatigue severity were associated with low income and stress. Sixth-year medical students (interns) experience intense working conditions and need to prepare for medical specialization examination. All these stress factors negatively affect students’ sleep quality. An online survey was conducted in 223 out of 534 interns between April and July 2023 in a university hospital in Türkiye. Sleep quality, fatigue and stress levels were evaluated by Pittsburgh Sleep Quality Index (PSQI), Chalder Fatigue Scale (CFS) and Visual Analogue Scale (VAS), respectively (PSQI >5, CFS ≥29, VAS 6.78 ± 1.82 (range 0–10), with higher values indicating greater momentary perceived stress.). Out of 223 interns (46.1% women, mean age 24 years), 177 (79.4%) had poor sleep quality. Moderate or high fatigue severity was observed in 94.4% of the students with poor sleep quality, whereas only 52.2% of those with good sleep quality had moderate fatigue risk (p<0.001). Participants with poor sleep quality had lower incomes (p=0.002), higher stress levels (p=0.005) and higher fatigue scores (p=0.001) compared to those with good sleep quality. Additionally, low socioeconomic status (odds ratio [OR], 25.625, 95% confidence interval [CI] 3.313-98.196; p=0.002), increased stress levels (OR, 2.838, CI 1.369-5.882; p=0.005), high stress (OR, 2.053, CI 1.051-4.010; p=0.035), and fatigue severity (OR, 15.308, CI 6.470-36.223; p<0.001) were associated with poor sleep quality. Most of the interns (79.4%), working under demanding conditions, had poor sleep quality, leading to increased risk of fatigue severity. Low incomes and high stress levels were predictors of poor sleep quality.