Functional insomnia in relation to alexithymic features and cortisol hypersecretion in a community sample

The occurrence of alexithymic features (inability to verbalize emotions) and cortisol hypersecretion was investigated in 257 subjects drawn from a Finnish adult community sample. Seventy‐five were considered to have poor sleep, 154 were good sleepers and 28 intermediate sleepers. The quality of sleep was investigated with the help of a self‐report‐based questionnaire, and alexithymic features were assessed during a psychiatric interview. Cortisol hypersecretion was measured by the dexamethasone suppression test (DST). Alexithymic features were clearly related to self‐reported insomnia and especially to long sleep latency (SL). Age and sex covaried with the relation between alexithymic features and quality of sleep. However, independent of age and sex, subjects with alexithymic features reported significantly more insomnia, difficulty in maintaining sleep (DMS) and parasomnias than non‐alexithymics. Though the occurrence of DST non‐suppressors did not differ in the good and the poor sleepers, the post‐dexamethasone cortisol level positively associated with alexithymic features. The data support but do not definitely prove the arousal theory of functional (psychophysiological) insomnia, ie a tendency of internalize psychic conflicts and an inability to verbalize them may lead to increased arousal and subsequent insomnia.