Human Studies

To investigate the correlation between the numerical rating scale, visual analogue scale, and pressure threshold by algometry in women with chronic pelvic pain.

The opioid risk tool (ORT) is a commonly employed measure of risk of aberrant drug related behaviors (ADRB) in patients with chronic pain prescribed opioid therapy. In this study the discriminant predictive validity of the ORT was evaluated in a unique cohort of patients with chronic nonmalignant pain (CNMP) on long-term opioid therapy (LTOT) that displayed no evidence of developing an opioid use disorder (OUD) and a sample of patients with CNMP that developed an OUD after commencing opioid therapy. Results revealed that the original ORT was able to discriminate between patients with and without OUDs (OR=1.624; CI 95%: 1.539-1.715, p< 0.001). A weighted ORT eliminating the gender specific history of preadolescent sexual abuse item revealed comparable results (OR= 1.648; CI 95%: 1.539-1.742, p< 0.001). A revised unweighted ORT (ORT-OUD) removing the history of preadolescent sexual abuse item was notably superior in predicting the development of OUD in patients with CNMP on LTOT (OR= 3.085; CI 95%: 2.725-3.493, p< 0.001) with high specificity (0.851; CI 95%: 0.811-0.885), sensitivity (0.854; 95% CI: 0,799-0.898), positive (0.757; CI 95%: 0.709-0.799) and negative (0.914; CI 95%: 0.885-0.937) predictive values. Perspective: The revised ORT (ORT-OUD) is the first tool developed on a unique cohort to predict the risk of developing an OUD in patients with CNMP receiving opioid therapy, as opposed to ADRB that can reflect a number of other issues. The ORT-OUD has clinical utility in providing clinicians a simple, validated method to rapidly screen for the risk of developing OUD in patients on or being considered for opioid therapy.

Fabry disease (FD) is an X-linked lysosomal storage disorder associated with pain triggered by heat or febrile infections. We modelled this condition by measuring the cytokine expression of peripheral blood mononuclear cells (PBMC) from FD patients in vitro upon stimulation with heat and lipopolysaccharide (LPS). We enrolled 67 FD patients and 37 healthy controls. We isolated PBMC, assessed their gene expression of selected pro- and anti-inflammatory cytokines, incubated them with heat, LPS, globotriaosylceramide (Gb3), and tumor necrosis factor-α (TNF), and measured TNF secretion in the supernatant and intracellular Gb3 accumulation, respectively. We found increased TNF, interleukin (IL-)1β, and toll-like receptor 4 (TLR4) gene expression in FD men (p < .05 to p < .01). TNF and IL-10 were higher, and IL-4 was lower in the subgroup of FD men with pain compared to controls (p < .05 to p < .01). Hereby, TNF was only increased in FD men with pain and classical mutations (p < .05) compared to those without pain. PBMC from FD patients secreted more TNF upon stimulation with LPS (p < .01) than control PBMC. Incubation with Gb3 and an additional α-galactosidase A inhibitor did not further increase TNF secretion, but incubation with TNF greatly increased the Gb3 load in FD PBMC compared to controls (p < .01). Also, LPS incubation and heat challenge (40 °C) increased Gb3 accumulation in PBMC of patients compared to baseline (p < .05 each), while no alterations were observed in control PBMC. Our data show that TNF holds a crucial role in the pathophysiology of FD associated pain, which may open a novel perspective for analgesic treatment in FD pain.

Chronic pain patients managed with opioids are at an increased risk of opioid misuse or opioid use disorder (OUD). In recent years, there has seen a stark increase in abuse, misuse, and diversion of prescription opioid medications. The aim of this study is to investigate trends in changing rates of opioid use disorder amongst chronic pain patients.

The present study aimed to: (1) better understand physical activity levels in youth with chronic abdominal pain and (2) investigate the relationship between day-level physical activity related to next day pain intensity to identify any intra-individual heterogeneity.

Chronic or persistent pain is a growing global health problem. Effective management of pain emerging in childhood may prevent long-term health and vocational consequences. Internationally, paediatric pain services are a limited resource and, as such, must strive to improve equity, outcomes and value for money. The Paediatric electronic Persistent Pain Outcomes Collaboration (PaedePPOC) is a bi-national paediatric outcome measurement centre that aims to measure, benchmark, and improve children's specialist pain services in Australasia. This study documents the establishment of PaedePPOC and presents baseline and initial outcome data. Bi-national consensus meetings determined the measures. Governance structures, collection protocols, information technology, site-specific logistics and onsite training were achieved within 18 months. Children and parents complete baseline and progress questionnaires. Seven of ten Australasian services provided data to PaedePPOC, with 1432 patients enrolled to June 2018. At baseline, patients were 12.4±[3.0] years, 68% female, 93% Australian-born, and 5% Aboriginal and/or Torres Strait Islander people. Most had moderate-severe functional disability and impaired quality of life, with pain affecting school attendance and employment. Opioid-containing medicines were used often or daily by 16%. Patients completing outcome measures at treatment end reported clinically significant improvement in pain intensity (49% of patients), functional ability (59%) and quality of life (69%). The PaedePPOC initiative has been successfully integrated into children's pain services, yielding timely point-of-care information to support clinicians and families, and valuable bi-national and service data to inform quality improvement and future sector planning.