Cardiac autonomic function is preserved in young adults with major depressive disorder.

The prevalence of major depressive disorder (MDD) is highest in young adults and contributes to an increased risk of developing future cardiovascular disease (CVD). However, the underlying mechanisms remain unclear. The studies examining cardiac autonomic function that have included young unmedicated adults with MDD report equivocal findings, and few have considered the potential influence of disease severity or duration. We hypothesized that heart rate variability (HRV) and cardiac baroreflex sensitivity (BRS) would be reduced in young unmedicated adults with MDD (18-30 yr old) compared with healthy nondepressed young adults (HA). We further hypothesized that greater symptom severity would be related to poorer cardiac autonomic function in young adults with MDD. Heart rate and beat-to-beat blood pressure were continuously recorded during 10 min of supine rest to assess HRV and cardiac BRS in 28 HA (17 female, 22 ± 3 yr old) and 37 adults with MDD experiencing current symptoms of mild-to-moderate severity (unmedicated; 28 female, 20 ± 3 yr old). Neither HRV [root mean square of successive differences between normal heartbeats (RMSSD): 63 ± 34 HA vs. 79 ± 36 ms MDD; P = 0.14] nor cardiac BRS (overall gain, 21 ± 10 HA vs. 23 ± 7 ms/mmHg MDD; P = 0.59) were different between groups. In young adults with MDD, there was no association between current depressive symptom severity and either HRV (RMSSD, R2 = 0.004, P = 0.73) or cardiac BRS (overall gain, R2 = 0.02, P = 0.85). Taken together, these data suggest that cardiac autonomic dysfunction may not contribute to elevated cardiovascular risk factor profiles in young unmedicated adults with MDD of mild-to-moderate severity.NEW & NOTEWORTHY This study investigated cardiac autonomic function in young unmedicated adults with major depressive disorder (MDD). The results demonstrated that both heart rate variability and cardiac baroreflex sensitivity were preserved in young unmedicated adults with MDD compared with healthy nondepressed young adults. Furthermore, in young adults with MDD, current depressive symptom severity was not associated with any indices of cardiac autonomic function.

Impact of sleep deficiency on surgical performance: a prospective assessment.

STUDY OBJECTIVES: Sleep deficiency can adversely affect the performance of resident physicians, resulting in greater medical errors. However, the impact of sleep deficiency on surgical outcomes, particularly among attending surgeons, is less clear. METHODS: Sixty attending surgeons from academic and community departments of surgery or obstetrics and gynecology were studied prospectively using direct observation and self-report to explore the effect of sleep deprivation on patient safety, operating room communication, medical errors, and adverse events while operating under 2 conditions, post-call (defined as > 2 hours of nighttime clinical duties) and non-post-call. RESULTS: Each surgeon contributed up to 5 surgical procedures post-call and non-post-call, yielding 362 cases total (150 post-call and 210 non-post-call). Most common were caesarian section and herniorrhaphy. Hours of sleep on the night before the operative procedure were significantly less post-call (4.98 ± 1.41) vs non-post-call (6.68 ± 0.88, P < .01). Errors were infrequent and not related to hours of sleep or post-call status. However, Non-Technical Skills for Surgeons ratings demonstrated poorer performance while post-call for situational awareness, decision-making, and communication/teamwork. Fewer hours of sleep also were related to lower ratings for situational awareness and decision-making. Decreased self-reported alertness was observed to be associated with increased procedure time. CONCLUSIONS: Sleep deficiency in attending surgeons was not associated with greater errors during procedures performed during the next day. However, procedure time was increased, suggesting that surgeons were able to compensate for sleep loss by working more slowly. Ratings on nontechnical surgical skills were adversely affected by sleep deficiency. CITATION: Quan SF, Landrigan CP, Barger LK, et al. Impact of sleep deficiency on surgical performance: a prospective assessment. J Clin Sleep Med. 2023;19(4):673-683.

Scale space detector for analyzing spatiotemporal ventricular contractility and nuclear morphogenesis in zebrafish.

In vivo quantitative assessment of structural and functional biomarkers is essential for characterizing the pathophysiology of congenital disorders. In this regard, fixed tissue analysis has offered revolutionary insights into the underlying cellular architecture. However, histological analysis faces major drawbacks with respect to lack of spatiotemporal sampling and tissue artifacts during sample preparation. This study demonstrates the potential of light sheet fluorescence microscopy (LSFM) as a non-invasive, 4D (3days + time) optical sectioning tool for revealing cardiac mechano-transduction in zebrafish. Furthermore, we have described the utility of a scale and size-invariant feature detector, for analyzing individual morphology of fused cardiomyocyte nuclei and characterizing zebrafish ventricular contractility.