Autobiographical memory predicts cognitive but not somatic change in sleep apnea patients vulnerable for affective disorder☆

Abstract 

Background: Autobiographical memory style (AM) can serve as a marker for determining susceptibility for depression. Currently and formerly depressed persons show reduced specific memory for autobiographical events. AM also has proven to be a reliable predictor for the remissive course of depression. Recently the issue arose as to whether this predictive power depends on particular dimensions of depression (cognitive, somatic). Methods: To replicate the predictability in vulnerable patients, we tested two groups of obstructive sleep apnea patients (OSAS) before and 2 months after initiation of nasal continuous positive airway pressure therapy (nCPAP). One group had a history of major depression (vulnerable persons; VUL), and the other group did not (NON-VUL). Sensitivity of AM on the dimensions of depression was assessed through two published versions of the cognitive and somatic subscales of the Beck Depression Inventory (BDI). Results: There was a significant interaction of Group by AM recall after presentation of positively valenced cues (AM_pos) on the cognitive but not on the somatic dimension of the BDI. Only in the VUL did AM_pos predict recovery. Limitations: Generalizability to other patient populations awaits further research. Reliability of the vulnerability assessment prior to the OSAS onset was not established. Conclusions: First, our findings further support the trait assumption of AM. Second, the AM methodology suggests sensitivity to only the cognitive dimensions of depression.

Keywords:  Autobiographical memory, Sleep apnea syndrome, Prediction, Depression, Beck Depression Inventory subscales