The Pittsburgh Sleep Quality Index in older primary care patients with generalized anxiety disorder: psychometrics and outcomes following cognitive behavioral therapy.

The Pittsburgh Sleep Quality Index (PSQI) is a widely used, comprehensive self-report measure of sleep quality and impairment, which has demonstrated good psychometric properties within various populations, including older adults. However, the psychometric properties of the PSQI and its component scores have not been evaluated for older adults with generalized anxiety disorder (GAD). Additionally, changes in PSQI global or component scores have not been reported following cognitive-behavioral treatment (CBT) of late-life GAD. This study examined (1) the psychometric properties of the PSQI within a sample of 216 elderly primary care patients age 60 or older with GAD who were referred for treatment of worry and/or anxiety; as well as (2) response to CBT, relative to usual care, for 134 patients with principal or coprincipal GAD. The PSQI demonstrated good internal consistency reliability and adequate evidence of construct validity. Those receiving CBT experienced greater reductions in PSQI global scores at post-treatment, relative to those receiving usual care. Further, PSQI global and component scores pertaining to sleep quality and difficulties falling asleep (i.e., sleep latency and sleep disturbances) demonstrated response to treatment over a 12-month follow-up period. Overall, results highlight the usefulness of the PSQI global and component scores for use in older adults with GAD.