Comparison of actigraphy indices among patients with depression and schizophrenia: A preliminary study

BACKGROUND: Schizophrenia (SCZ) and depression (MDD) are associated with changes in sleep and activity patterns. However, because of a lack of objective evaluation, the diagnostic or clinical value of these sleep-activity patterns is unknown. In this study, we attempted to assess and compare the sleep and activity patterns using actigraphy. MATERIALS AND METHODS: We have recruited 35 patients with SCZ (mean age: 29.29 ± 7.54 years) and 42 patients with MDD (mean age: 27.5 ± 5.59 years) in this cross-sectional study. The actigraphy indices [Time in bed (minutes), Onset latency (minutes), Total sleep time (Minutes), Sleep efficiency (%), WASO (minutes), number of awakening, and activity duration (minutes) were compared among the two groups using unpaired t-test and Fisher exact test. RESULTS: In the MDD group, the time in bed (minutes) was significantly higher than in the SCZ group (402.7 ± 41.97 vs. 379.1 ± 40.45, P = 0.01), while the sleep efficiency was lower in the SCZ group than in the MDD group (60.04 ± 9.25 vs. 65.05 ± 7.16, P = 0.0092). An increase in onset latency (minutes) was observed in the SCZ group compared to the MDD group (49.06 ± 16.09 vs. 43.6 ± 10.14, P = 0.074). The difference in WASO (minutes), the number of awakenings, and activity duration (minutes) among the two groups were insignificant. CONCLUSION: Actigraphy parameters such as sleep efficiency and time in bed may be a useful sleep process, etiological, and prognostic markers in patients with SCZ and MDD. The longitudinal studies are needed to estimate the predictive role of these parameters for therapeutic outcome in these patients.