Immunological Consequences of Poor Sleep: A Biomarker an PSQI – Based Investigation into Immune Dysrehulation

Background: Sufficient, high-quality sleep is essential for maintaining balanced human immune defenses. In the Basra health community, inadequate rest is linked to reduced immunity, increasing susceptibility to metabolic challenges and infections. This study investigated how daily sleep habits influence systemic inflammatory markers. Methods: A cross-sectional study evaluated 120 adults aged 22–45 over seven consecutive days. Sleep metrics were measured using objective actigraphy tracking and subjective Pittsburgh Sleep Quality Index (PSQI) scores. Peripheral blood samples were analyzed for total leukocyte counts, C-reactive protein (CRP), TNF-α, and IL-6 levels. Data were evaluated using Pearson correlation and multiple regression analysis. Results: Participants with poor sleep (PSQI > 5, duration < 6 hours) exhibited significantly elevated concentrations of TNF-α and IL-6 compared to well-rested peers (p < 0.01). A positive correlation emerged between longer sleep duration and higher total white blood cell (WBC) counts (r = 0.42, p < 0.05), highlighting sleep's role in immune surveillance. Regression models confirmed poor sleep quality as an independent predictor of heightened systemic inflammation. Conclusion: Sleep quality directly regulates human immune function, with chronic poor sleep triggering low-grade systemic inflammation and disrupting immune stability. Improving sleep hygiene should be prioritized as a key preventative strategy in clinical healthcare settings.