Inferring sleep disturbance from text messages of suicide attempt survivors: A pilot study

OBJECTIVE: Identifying digital markers of sleep disturbance—a known suicide risk factor—may aid in the detection of imminent suicide risk. This study examined sleep‐related communication and texting patterns in personal text messages (N = 86,705) of suicide attempt survivors. METHOD: Twenty‐six participants provided dates of past suicide attempts and 2‐week periods of positive mood, depressed mood, or suicidal ideation. Linguistic Inquiry Word Count was used to identify sleep‐related texts via a custom dictionary. Mixed effect models were fitted to test the association between suicide/mood episode type (e.g., attempt versus ideation) and three outcomes: likelihood of a text including sleep‐related content, nightly count of texts sent from midnight to 5:00 AM, and sum of unique hour bins from midnight to 5:00 AM with outgoing texts. RESULTS: Analyses with a sleep dictionary that was manually revised to be more accurate (but not the original unedited dictionary) showed sleep‐related communication was more likely during depressed mood episodes than positive mood episodes. Otherwise, there were no significant differences in sleep‐related communication or objective texting patterns across episode type. CONCLUSIONS: Although we did not detect differences in sleep‐related communication tied to suicidal thoughts or behaviors, sleep‐related communication may differ as a function of within‐person mood level.