Association between Experimental Pain Measurements and the Central Sensitization Inventory in Patients at Least 3 Months after COVID-19 Infection: A Cross-Sectional Pilot Study

Abstract

Fatigue, pain, headache, brain fog, anosmia, ageusia, mood symptoms, and sleep disorders are symptoms commonly experienced by people with post-COVID-19 condition. These symptoms could be considered as manifestations of central sensitization. The aim of this study is to evaluate whether there are indicators of central sensitization by using experimental pain measurements and to determine their association with patient-reported outcome measures (PROMs). A cross-sectional study including 42 patients after COVID-19 infection was conducted. The central sensitization inventory (CSI) was administered as a PROM to evaluate central-sensitization-associated symptoms. Pressure pain thresholds (PPT), temporal summation, and descending nociceptive pain inhibition (CPM) were assessed as experimental pain measurements. The median score on the CSI was 46.5 (Q1-Q3:33–54). The presence of central-sensitization-associated symptoms was seen in 64.3% of patients based on the CSI (≥40/100 points). A deficient CPM was seen in 12% and 14% of patients when measured at the trapezius and rectus femoris, respectively. A negative correlation between pressure sensitivity on the rectus femoris and the CSI score (r = −0.36, 95%CI −0.13 to −0.65, p = 0.007) was observed. Central-sensitization-associated symptoms were present in up to 64.3% of patients post-COVID-19 infection, based on a PROM, i.e., the CSI. A more objective evaluation of nociceptive processing through experimental pain measurements was less suggestive of indicators of central sensitization. Only a small negative correlation between pressure sensitivity and the CSI was observed, thereby pointing towards the discrepancy between the CSI and experimental pain measurements and presumably the complementary need for both to evaluate potential indicators of central sensitization in this population.

Serological Biomarkers at Hospital Admission and Hospitalization Treatments Are Not Related to Sensitization-Associated Symptoms in Patients with Post-COVID Pain

“…The presence of sensitization-associated symptoms in patients with post-COVID pain has been previously observed [19][20][21]. In fact, it has been previously suggested that some individuals with post-COVID pain can exhibit nociplastic features and may require a more nuanced multimodal treatment approach to achieve better treatment outcomes [42].…”

“…Some studies have identified the presence of sensitization-associated symptoms, assessed by Central Sensitization Inventory (CSI), in a range between 30% [19] and 70% [20] of patients with post-COVID pain. A recent pilot study identified the presence of a deficient conditioned pain modulation (CPM) in almost 15% of patients with post-COVID pain [21]. Identification of risk factors associated with sensitization-associated symptoms in individuals with post-COVID pain could help more personalized interventions.…”

Melatonin as a Coadjuvant in the Treatment of Patients with Fibromyalgia

“…Fatigue, pain, headache, brain fog, mood and sleep disorders, among others, are symptoms commonly experienced in post-COVID-19 patients. These symptoms could be considered as manifestations of central sensitization [111]. In fact, fatigue is one of the core symptoms in central-sensitizationassociated disorders [112], leading to the hypothesis that central sensitization might be an underlying common etiology in chronic pain patients and in patients with post-COVID-19 condition [113].…”

Association of Kinesiophobia with Catastrophism and Sensitization-Associated Symptoms in COVID-19 Survivors with Post-COVID Pain

“…Different studies have reported a heterogeneous location of post-COVID pain, with a prevalence of 20-25% for widespread distribution [12][13][14]. The presence of widespread pain is associated with altered nociceptive processing, which has been recently identified in individuals with post-COVID pain [15].…”