Diagnostic and Statistical Manual criteria for insomnia related impairment in daytime functioning: polysomnographic correlates in older adults.

OBJECTIVE: Diagnosis of insomnia disorder by the Diagnostic and Statistical Manual (DSM)-IV, and as proposed by the DSM-V, includes criteria for impairment in occupational- or social functioning due to sleep complaints. This study evaluated the clinical and polysomnographic correlates of impairment in daytime functioning in older adults with insomnia.

METHODS: In older adults with DSM-IV chronic insomnia (n=68), clinical and demographic information, and measures of health functioning, medical co-morbidity, and polysomnographic sleep were obtained. Four questions that evaluated difficulties or distress in occupational- or social functioning related to sleep complaints were used to code DSM threshold criteria for impairment in daytime functioning. Stepwise regression was used to identify predictors of impairment in daytime functioning.

RESULTS: Impairment in daytime functioning was significantly associated with younger age (p<0.05), and the amount of wake time after sleep onset as assessed by polysomnography (p<0.001), controlling for health functioning and minority racial status.

CONCLUSIONS: Amount of wake time after sleep onset uniquely contributes to criteria symptoms of impairment in daytime functioning among older adults with insomnia. Treatments that target sleep maintenance have the potential to improve social and occupational functioning in older adults with sleep complaints.