TO SLEEP OR NOT TO SLEEP: A preliminary report on the impact of total sleep deprivation on peripheral and central pain mechanisms

Abstract

Background and aims: Chronic pain and poor sleep are often reported in unison, but how impaired sleep may yield increased pain sensitivity is not clear. Therefore, this study aimed to use a total sleep deprivation (TSD) model to investigate the impact of disrupted sleep on central pain mechanisms and widespread muscle hyperalgesia. Methods: Twenty-three healthy right-handed participants (F: 9; M: 14; age±SD: 25.87±6.96) attended two sessions, separated by 24 hrs. At baseline and 24 hrs after TSD, muscle pain sensitivity (pressure pain thresholds; PPTs) was measured from supra- and infraspinatus, lower trapezius, and the gastrocnemius, while temporal summation of pain (TSP) and pressure detection threshold (PDT) with and without a conditioning stimulus were assessed by cuff algometry. Results. Significantly lower PPTs were found at follow-up compared to baseline (p=0.001) for all muscles expect supraspinatus (p=0.058). At baseline, a significant increase in conditioned PDT was found compared to non-conditioned PDT (28.31±2.47 vs. 40.52±5.45, respectively, p=0.006), indicating a functional descending pain control. Conversely, after TSD, this increase in PDT was abolished (33±3.34 vs. 35.97±4.75, p=0.42), which may suggest that sleep is important to maintain proper descending pain control. A trend towards significantly lower non-conditioned PDTs were found at follow-up when compared to baseline (p=0.054). Temporal summation of pain was not affected by TSD (3.02±1.13 vs. 3.94±0.47, baseline versus TSD session respectively, p=0.38). Conclusions. These preliminary data suggests that TSD can impair descending pain control and induce widespread muscle hyperalgesia.