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Psychometric assessment of the Swedish version of the injustice experience questionnaire among patients with chronic pain.

The use of the Injustice Experience Questionnaire (IEQ) in psychological assessment of individuals with chronic pain is supported by research. The psychometric properties of the Swedish version, the IEQ-S, has not yet been evaluated. Hence, the aim was to investigate structural validity, and concurrent criterion validity of the IEQ-S against the Work Ability Index (WAI), the Pain Catastrophizing Scale (PCS-SW), the Patient Health Questionnaire 9-item depression module (PHQ-9), and the Generalized anxiety disorder 7-item scale (GAD-7). Internal consistency and test-retest reliability were also studied.

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Treatment of medication overuse headache: Effect and predictors after 1 year-A randomized controlled trial.

Combined withdrawal and early preventive medication was the most effective treatment for medication overuse headache (MOH) within the first 6 months in a previous study, but results from a longer follow-up period are lacking.

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Experimental evidence of a functional relationship within the brainstem trigeminocervical complex in humans.

The existence of a trigeminocervical complex (TCC) has been suggested based on animal data, but only indirect evidence exists in humans. We investigated the functional relationship between the trigeminal and the occipital region by stimulating one region and measuring electrical pain thresholds (EPTs) of the corresponding opposite region. This study consists of two single-blinded, randomized protocols. 40 healthy participants were recruited in the propaedeutic Protocol I. EPTs were measured on the V1 and the greater occipital nerve (GON) dermatome bilaterally as well as on the left forearm longitudinally before and after application of topical capsaicin. Protocol II was then online pre-registered and, additionally, the ipsilateral trigeminal dermatomes V2 and V3 were tested. GON stimulation increased the EPT ipsilateral at V1 after 20 minutes (p=0.006) compared to baseline, whereas trigeminal stimulation increased the EPT at the ipsilateral (p=0.023) as well as the contralateral GON (p=0.001) following capsaicin application. Protocol II confirmed these results and additionally showed that GON stimulation with capsaicin increased EPTs ipsilateral at all three trigeminal dermatomes and that trigeminal stimulation on V1 led to an ipsilateral increase of EPTs at GON, V2 and V3. Our data suggest a strong functional interplay between the trigeminal and occipital system in humans. The fact that stimulation of one of these dermatomes increases the electrical pain threshold of the respective other nerve could be explained by segmental inhibition on brainstem level.

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Impact of changes in opioid funding and clinical policies on rapid tapering of opioids in Ontario, Canada.

Reports have emerged of abrupt tapering among recipients of long-term prescription opioids to conform to new prescribing guidelines. We conducted a population-based, repeated cross-sectional time-series study among very high-dose (≥200 MME) opioid recipients in Ontario, Canada, to examine changes in the monthly prevalence of rapid tapering from 2014 to 2018, defined as recipients experiencing either a ≥50% reduction in daily doses or abrupt discontinuation sustained for 30 days. Interventional autoregressive integrated moving average (ARIMA) models were used to test for significant changes following key guidelines, and drug policies and programs. A sensitivity analysis examined rapid tapering sustained for 90 days. The monthly prevalence of rapid tapering events was stable from January 2014 to September 2016 (average monthly prevalence: 1.4%), but increased from 1.4% in October 2016 to 1.8% in April 2017 (p=0.001), coincident with Ontario's Fentanyl Patch-for-Patch Return Program implementation. Transient spikes in the prevalence of rapid tapering also occurred two months following Ontario's delisting of publicly funded high-strength opioids and the release of updated Canadian Opioid Prescribing Guideline for Chronic Pain, reaching 2.3% in March 2017 and July 2017, respectively. However this prevalence decreased to 1.2% in December 2018 (p<.0001). Although the prevalence of abrupt opioid discontinuation was lower, similar trends were observed. Our sensitivity analysis examining longer-lasting rapid tapering found similar trends but lower prevalence, with no changes in complete discontinuation. These temporary increases in rapid tapering events highlight the need for improved communication and evidence-based resources for prescribers to minimize negative consequences of evolving policies and guidelines.

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CACNA1A-p.Thr501Met mutation associated with familial hemiplegic migraine: a family report.

Hemiplegic migraine (HM) is a rare form of migraine characterized by the presence of a motor and other types of aura. HM can be sporadic or familial. Familial hemiplegic migraine (FHM) is an autosomal dominant disorder, classified into 3 subtypes, based on the gene involved (CACNA1A in FHM1, ATP1A2 in FHM2 and SCN1A in FHM3). The clinical presentation is highly heterogeneous and some attacks may be severe. We report the clinical characteristics and genetic analysis of 12 patients belonging to a family with CACNA1A-p.Thr501Met gene mutation.

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A Biofeedback App for Migraine: Development and Usability Study.

Biofeedback is effective in treating migraines. It is believed to have a beneficial effect on autonomous nervous system activity and render individuals resilient to stressors that may trigger a migraine. However, widespread use of biofeedback is hampered by the need for a trained therapist and specialized equipment. Emerging digital health technology, including smartphones and wearables (mHealth), enables new ways of administering biofeedback. Currently, mHealth interventions for migraine appear feasible, but development processes and usability testing remain insufficient.

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The effect of long-term poor sleep quality on risk of back-related disability and the modifying role of physical activity.

Sleep problems and regular leisure time physical activity (LTPA) are interrelated and have contrasting effects on risk of back pain. However, no studies have investigated the influence of long-term poor sleep quality on risk of back-related disability, or if LTPA modifies this association. The study comprised data on 8601 people who participated in three consecutive surveys over ~ 22 years, and who reported no chronic back pain at the two first surveys. Adjusted risk ratios (RRs) for back-related disability were calculated at the last survey, associated with the joint effect of changes in sleep quality between the two first surveys and meeting physical activity guidelines at the second survey. Compared to people with long-term good sleep, people with long-term poor sleep had nearly twice the risk of back-related disability (RR 1.92, 95% CI 1.48-2.49). There was no statistical interaction between sleep and LTPA but people who reported long-term poor sleep and meeting the physical activity guidelines had 35% lower risk of back-related disability compared to people with same level of sleep problems, but who not met the guidelines. These findings suggest that long-term poor sleep quality contributes to a substantially increased risk of chronic and disabling back pain irrespective of LTPA.

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Automated slice-specific z-shimming for fMRI of the human spinal cord.

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Tapering of prescribed opioids in patients with long-term non-malignant pain (TOPIO)-efficacy and effects on pain, pain cognitions, and quality of life: a study protocol for a randomized controlled clinical trial with a 12-month follow-up.

Opioids are still widely prescribed to long-term pain patients although they are no longer recommended for long-term treatments due to poor evidence for long-term efficacy, risks of serious side effects, and the possibility of inducing opioid hyperalgesia. In a Cochrane study from 2017, the authors identified an urgent need for more randomized controlled trials investigating the efficiency and effects of opioid tapering. The study aimed to assess (1) the efficiency of a structured intervention in causing stable reductions of opioid consumption in a population with long-term non-malignant pain and (2) effects on pain, pain cognitions, physical and mental health, quality of life, and functioning in response to opioid tapering.

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Expected impact of lockdown measures due to COVID-19 on disabling conditions: a modelling study of chronic low back pain.

The COVID-19 pandemic and the containment measures such as social distancing, mobility restrictions and quarantine have significantly impacted the delivery of healthcare services, with possible negative effects on low back pain patients. In this study, we used an innovative agent-based model to quantify the effects of COVID-19 on the prevalence and severity of low back pain in the general population.

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