Elevated highly sensitive C-reactive protein in fibromyalgia associates with symptom severity

Abstract

OBJECTIVES Fibromyalgia, a common pain syndrome, is thought to be a non-inflammatory, nociplastic condition but evidence implicating neuroinflammation has been increasing. Systemic inflammation may be associated with more severe symptoms in some fibromyalgia patients. We studied healthy controls and fibromyalgia patients with and without systemic inflammation detectable using high-sensitivity C-reactive protein (hsCRP) measurement. METHODS We measured hsCRP levels, and gathered clinical and questionnaire data (including Fibromyalgia Impact Questionnaire (FIQ)), from 40 female fibromyalgia patients and 30 age-matched healthy women: hsCRP > 3 mg/l was considered elevated. RESULTS Fibromyalgia patients had significantly higher mean hsCRP levels than controls, explained by overweight and lower leisure-time physical activity. Eight fibromyalgia patients had elevated, and 29 normal, hsCRP. Levels of hsCRP were significantly correlated with FIQ scores. Patients with elevated hsCRP had higher FIQ scores, with worse physical functioning and greater pain, and were less likely to be in work, than patients with normal hsCRP. These patient groups did not differ by blood count, liver function, or lipid profiles, nor by education, psychological measures, sleep disturbance, smoking, or comorbidities. CONCLUSION Some fibromyalgia patients have elevated hsCRP, mostly due to overweight and physical inactivity. They have worse symptoms and their ability to work is impaired. Measurement of hsCRP may help to identify fibromyalgia patients in greatest need of interventions supporting working ability. TRIAL REGISTRATION ClinicalTrials.gov, https://clinicaltrials.gov, NCT03300635 Lay summary What does this mean for patients? People with fibromyalgia suffer from persistent pain and reduced physical functioning. Severity of fibromyalgia symptoms varies greatly between patients. Laboratory tests have not been able to confirm fibromyalgia or gauge its severity. C-reactive protein (CRP) is a commonly used indicator of inflammation; even low levels of inflammation are known to predict worse health outcomes. In our study, we measured the CRP levels of 40 female patients with fibromyalgia and collected data on their medical history and lifestyle factors. We found that patients with above normal levels of CRP had worse symptoms, lower physical functioning and were less likely to be able to work. This increased inflammation was mostly explained by being overweight and having reduced physical activity, and not by, for example, other medical conditions. Although some patients had severe symptoms without inflammation, our results suggest that a simple and widely available blood test could be useful for identifying patients with severe fibromyalgia. CRP measurements could also be used to monitor the effectiveness of lifestyle changes such as exercise and weight-loss in these individuals. Using medication to alleviate fibromyalgia symptoms through reduction of inflammation should also be studied in the future.

Machine learning identifies fatigue as a key symptom of fibromyalgia reflected in tyrosine, purine, pyrimidine, and glutaminergic metabolism

“…The study design and data acquisition have previously been described in detail 9–12 . In brief, the study cohort comprised 54 female patients with fibromyalgia, aged 18–65 years, from Helsinki University Hospital outpatient clinics, City of Vantaa primary health care, and the private clinic of one of the authors (R.M.).…”

“…The study design and data acquisition have previously been described in detail. 9 , 10 , 11 , 12 In brief, the study cohort comprised 54 female patients with fibromyalgia, aged 18–65 years, from Helsinki University Hospital outpatient clinics, City of Vantaa primary health care, and the private clinic of one of the authors (R.M.). Thirty‐one age‐matched female controls were recruited from the staff of these health care units and a local home economics organization (Uudenmaan Martat ry).…”

“…The study design and data acquisition have previously been described in detail. [9][10][11][12] In brief, the study cohort comprised 54 female patients with fibromyalgia, aged 18-65 years, from Helsinki University Hospital outpatient including changes in metabolism. However, it remains unclear what are the contributions of individual symptoms to fibromyalgia symptom burden, what metabolic changes are relevant for fibromyalgia, and whether different metabolic anomalies could be linked to individual symptoms of fibromyalgia.…”

C-Reactive Protein: Pathophysiology, Diagnosis, False Test Results and a Novel Diagnostic Algorithm for Clinicians

“…Its association with elevated CRP (mean approx. 6 mg/L) may be attributed to weight and other comorbidities, and indeed, another study discussed that some patients with this condition show higher serum hsCRP titers, mostly due to being overweight and physical inactive [ 475 , 476 , 477 ]. Overweight but also underweight individuals with Duchenne muscular dystrophy have been reported for increased CRP levels [ 478 ].…”

What Do We Know about Nociplastic Pain?

“…A study conducted on patients with LBP revealed the variability of the organization of the primary motor cortex, concluding that this difference is the origin of NcplP in this condition [ 31 , 32 ]. The level of C-reactive protein can also be associated with NcplP, as shown in a study conducted on patients with fibromyalgia in which a correlation between the C-reactive protein level and severity of pain was reported [ 33 ].…”