(227) Real-Time Associations Between Sleep Stage, Glucose, and Nocturnal Penile Tumescence

Abstract Introduction Sexual function, sleep, and nutrition represent three fundamental pillars of health and are key contributors to overall well-being. Sexual function is influenced by numerous comorbidities, and recent studies have highlighted the detrimental effects of diabetes, cardiovascular disease, stress, obstructive sleep apnea (OSA), and mental health disorders on sexual health. Nocturnal penile tumescence (NPT) is considered the gold standard indicator of erectile health and provides clinicians with valuable insight into the etiology of erectile abnormalities. Objective The objective of this study was to investigate the relationship between real-time nocturnal erections, concurrent glucose levels, and sleep stage. Methods We conducted a prospective observational study including men over 18 years of age with no history of erectile dysfunction, diabetes mellitus, or sleep disorders. Participants recorded nocturnal data over two weeks using three devices: the FirmTech TechRing to monitor nocturnal erections, a continuous glucose monitor providing hourly minimum and maximum glucose levels, and the Whoop device for sleep staging. Data were analyzed using descriptive statistics and correlation tests. Results Four men were included in the study (mean age 39 ± 19). Analysis of glucose data revealed a statistically higher glucose level during NPT episodes compared to non-NPT periods (89.0 ± 8.7 mg/dL vs. 86.8 ± 9.1 mg/dL, p 0.01), though levels remained within the normoglycemic range. Across 56 nights of monitoring, the mean duration of NPT was 206 ± 110 minutes per night. A linear mixed-effects model showed that, within individuals, each additional 100 minutes of REM/deep sleep was associated with an average increase of 31 minutes in NPT duration (p = 0.01). Between participants, higher average REM/deep sleep duration correlated strongly with longer mean NPT duration (r = 0.89, p = 0.007). Conclusions Our findings demonstrate a physiological link between restorative sleep and NPT, observable both within and between individuals. Additionally, we observed transient elevations in glucose during NPT, likely reflecting sympathetic nervous system activation and hepatic glucose release, which may provide the energy required to support the energy-dependent process of erection. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Firmtech