Sex differences in measures of central sensitization and pain sensitivity to experimental sleep disruption: implications for sex differences in chronic pain.

Study Objectives: Females demonstrate heightened central sensitization (CS), a risk factor for chronic pain characterized by enhanced responsivity of central nervous system nociceptors to normal or subthreshold input. Sleep disruption increases pain sensitivity, but sex has rarely been evaluated as a moderator and few experiments have measured CS. We evaluated whether two nights of sleep disruption alter CS measures of secondary hyperalgesia and mechanical temporal summation in a sex-dependent manner. We also evaluated differences in measures of pain sensitivity. Methods: Seventy-nine healthy adults (female n = 46) participated in a randomized crossover experiment comparing two consecutive nights of eight pseudorandomly distributed forced awakenings (FA [-200 min sleep time]) against two nights of undisturbed sleep (US). We conducted sensory testing the mornings following Night 2; the heat-capsaicin pain model was used to induce secondary hyperalgesia. Results: FA reduced total sleep time (REM and NREM Stage 3) more profoundly in males. We observed divergent, sex-dependent effects of FA on secondary hyperalgesia and temporal summation. FA significantly increased secondary hyperalgesia in males and significantly increased temporal summation in females. Sex differences were not attributable to differential sleep loss in males. FA also significantly reduced heat-pain threshold and cold pressor pain tolerance, independently of sex. Conclusions: Sleep disruption enhances different pain facilitatory measures of CS in males and females suggesting that sleep disturbance may increase risk for chronic pain in males and females via distinct pathways. Findings have implications for understanding sex differences in chronic pain and investigating sleep in chronic pain prevention efforts.

Heart Failure Rehospitalization and Delayed Decision Making: The Impact of Self-care and Depression.

BACKGROUND: Rehospitalization soon after discharge can be distressing for persons with heart failure (HF) and places a heavy burden on the healthcare system. OBJECTIVE: We investigated and explored the association of self-care decision making variables with (1) rehospitalization within 30 days of discharge and (2) delay in seeking medical assistance (delayed decision making). METHODS: A cross-sectional, explanatory sequential mixed methods design (quan > qual) was used to survey 127 hospitalized HF patients and interview 15 of these participants to explain their survey responses. The survey assessed rehospitalization within 30 days of discharge, delayed decision making, HF self-care, and psychosocial factors influencing self-care. RESULTS: The likelihood of delaying the decision to be hospitalized was more than 5 times higher among those with high depressive symptoms (odds ratio, 5.33; 95% confidence interval, 2.14-13.28). Those who delayed going to the hospital were uncertain about their prognosis and did not feel their symptoms were urgent. The likelihood of being rehospitalized within 30 days was more than doubled among those with high depressive symptoms (OR, 2.31; 95% confidence interval, 1.01-5.31). Those who were rehospitalized within 30 days were less likely to consult healthcare professionals in their decision making and wanted immediate relief from their symptoms. CONCLUSIONS: We recommend a patient-centered approach to help HF patients identify and adequately self-manage symptoms. The strong association between high depressive symptoms and rehospitalization within 30 days as well as delayed decision making highlights the critical need for clinicians to carefully assess and address depression among HF patients.