0647 Rest-activity pattern in Major depressive disorder - a case control study

Abstract

Abstract Introduction Disruption of rest-activity pattern are important behavioral manifestations in patients with major depressive disorder (MDD). Actigraphy provides accessible and objective measurement on physical activity, sleep, and circadian rhythm, but it was not widely used in studying patients with MDD, especially among Asian population. Methods Rest-activity pattern was recorded by Actiwatch Spectrum Plus/PRO for 7 continuous days. Physical activity and sleep estimation was processed by Philips Actiware software 6. Circadian rhythm characteristics were generated by using the “cosinor” and “nparACT” packages in R to perform the cosinor and nonparametric analysis respectively. Results A total of 70 MDD subjects, and 59 age- and sex-comparable controls were included in the actigraphy data analysis. The mean age of MDD subjects was 51.24 ± 10.39 years, and 71.4% of MDD subjects were female. Of these MDD subjects, 54.3% were unremitted for their depressive illness. For sleep and circadian features, MDD subjects had higher Insomnia Severity Index (ISI score, MDD: 10.29 ± 5.70; controls: 6.05 ± 5.20, P < 0.001) and lower reduced Morningness-Eveningness questionnaire (rMEQ score, MDD: 13.19 ± 4.62; controls: 16.07 ± 3.28, P < 0.001) than controls. The percentage of mobility measured by actigraphy was significantly lower in MDD patients than controls (MDD: 58.58%; controls: 62.27%, P < 0.001), albeit the difference only occurred during rest period. MDD subjects had later acrophase (P = 0.024), M10 midpoint (P = 0.040) and a trend of delayed sleep midpoint (P = 0.076) and longer sleep duration (P = 0.067) than controls. When the comparison was performed among three groups, unremitted MDD subjects showed a higher intra-individual variability of sleep midpoint than remitted MDD group (P = 0.021) and higher intra-individual variability for sleep duration than controls (P = 0.016). Conclusion MDD subjects had increased insomnia and eveningness than controls, which was supported by the acitgraphy data at which MDD had a tendency of longer major rest interval and delayed circadian phase. Unremitted MDD subjects showed a higher intra-individual variability of sleep midpoint and sleep duration. These actigraphy parameters may be useful markers for phenotyping and monitoring of MDD. Support (if any)