I am a
Home I AM A Search Login

Human Studies

Share this

Deceptive and Nondeceptive Placebos to Reduce Pain: An Experimental Study in Healthy Individuals.

Recent research has shown that placebos can be effective even if they are openly prescribed to participants. Yet, it is unclear how such "open-label placebos" (OLPs) compare to deceptive placebo (DP) and what the mechanisms of actions are. In this study, we therefore compared 2 versions of OLP to DP and no treatment (NT).

Unwelcome Companions: Loneliness Associates with the Cluster of Pain, Fatigue, and Depression in Older Adults.

Pain, fatigue, and depression commonly co-occur as a symptom cluster in pathological inflammatory states. Psychosocial stressors such as loneliness may lead to similar states through shared mechanisms. We investigated the association of loneliness with pain, fatigue, and depression in older adults. Using Health and Retirement Study data ( = 11,766), we measured cross-sectional prevalence of frequent, moderate to severe pain; severe fatigue; depressive symptoms; and co-occurrence of symptoms surpassing threshold levels (i.e., symptom cluster). Logistic regression models evaluated associations with loneliness. Pain, fatigue, and depression were reported in 19.2%, 20.0%, and 15.3% of the total sample, respectively. The symptom cluster was seen in 4.9% overall; prevalence in lonely individuals was significantly increased (11.6% vs. 2.3%,  < .0001). After adjusting for demographic variables, loneliness associated with the symptom cluster (adjusted OR = 3.39, 95% CI = 2.91, 3.95) and each symptom (pain adjusted OR = 1.61, 95% CI = 1.48, 1.76; fatigue adjusted OR = 2.02, 95% CI = 1.85, 2.20; depression adjusted OR = 4.34, 95% CI = 3.93, 4.79). Loneliness strongly associates with the symptom cluster of pain, fatigue, and depression. Further research should examine causal relationships and investigate whether interventions targeting loneliness mitigate pain, fatigue, and depression.

Inter-ictal assay of peripheral circulating inflammatory mediators in migraine patients under adjunctive cervical non-invasive vagus nerve stimulation (nVNS): A proof-of-concept study.

To assay peripheral inter-ictal cytokine serum levels and possible relations with non-invasive vagus nerve stimulation (nVNS) responsiveness in migraineurs.

The Burden of Disease in Germany at the National and Regional Level-Results in Terms of Disability–Adjusted Life Years (DALY) from the BURDEN 2020 Study.

measures such as disability-adjusted life years (DALY) are becoming increasingly important for the standardized assessment of the burden of disease due to death and disability. The BURDEN 2020 pilot project was designed as an independent burden-ofdisease study for Germany, which was based on nationwide data, but which also yielded regional estimates.

Association Between Temporomandibular Disorders Pain and Migraine: Results of the Health 2000 Survey.

To study the possible associations of various clinically assessed painful signs of temporomandibular disorders (TMD) with the presence of migraine using a large population-based dataset.

Patients With Fibromyalgia, Depression, and/or Anxiety and Sex Differences.

Fibromyalgia is a syndrome characterized by chronic widespread pain, with a multifactorial etiopathogenesis and high incidence of neuropsychiatric comorbidity. It has been inaccurately considered a pathological condition affecting only middle-aged women. The study aimed to explore the association of sociodemographic and clinical factors in patients with fibromyalgia with depression and/or anxiety. The present study is an analysis of a cross-sectional study of a secondary source. The prevalence ratio (PR) between the demographic and clinical variables of patients with fibromyalgia and concomitant depression and/or anxiety was calculated. Overall, 1,106 medical records were obtained with a confirmed diagnosis of fibromyalgia between 2010 and 2016; of these, 318 (28.75%) patients had an associated diagnosis of depression and/or anxiety. Approximately 28% women (295 of 1,052) and 42.6% men (23 of 54) suffered from depression and/or anxiety. In the adjusted explanatory model of depression and/or anxiety in patients with fibromyalgia, the relationship between sex (female PR = 0.5 [0.28-0.86]) and low socioeconomic strata (PR = 0.53 [0.33-0.70]) remained constant. In the study population, patients with fibromyalgia belonging to lower social strata were less likely to present with depression and anxiety. The male sex may pose as a risk factor for depression and/or anxiety in patients with fibromyalgia. Fibromyalgia has a huge impact on men's physical as well as mental health.

Is placebo analgesia for heat pain a sensory effect? An exploratory study on minimizing the influence of response bias.

We explored the ongoing question of whether placebo analgesia alters afferent nociceptive processing in a novel paradigm designed to minimize the role of response bias in placebo measurement. First, healthy adult participants received a standard heat placebo induction and conditioning procedure using a topical "analgesic" cream applied to one arm. During a subsequent placebo testing procedure, participants rated stimuli on the placebo-treated arm and untreated arm, using a task that minimized subjects' ability to guess the expected response, thus reducing experimenter demand. Retrospectively participants reported moderate analgesia effectiveness (mean=5.3/10), but for individual temperature ratings, only 2 subjects exhibited a perceptual placebo response >5 points. Next, these subjects completed a novel, exploratory task designed to measure changes in inter-arm in discriminative accuracy that would be expected from changes in afferent nociception. Both placebo responders (but no non-responders) showed reduced discriminative ability when the hotter stimulus occurred on the placebo arm, an effect consistent with alterations in nociceptive afferent flow and unlikely to be caused by response bias.

Linking non-restorative sleep and activity interference through pain catastrophizing and pain severity: An intra-day process model among individuals with fibromyalgia.

Non-restorative sleep is a key diagnostic feature of the musculoskeletal pain disorder fibromyalgia, and is robustly associated with poor physical functioning, including activity interference. However, the mechanisms through which non-restorative sleep elicits activity interference among individuals with fibromyalgia at the within-person level remain unclear. The present study tested the following three-path mediation model, using data gathered from a 21-day electronic daily diary in 220 individuals with fibromyalgia: previous night non-restorative sleep → morning pain catastrophizing → afternoon pain severity → end-of-day activity interference. Results of multilevel structural equation modeling supported the three-path mediation model. Previous night's non-restorative sleep and morning pain catastrophizing were also directly related to end-of-day activity interference. Previous night non-restorative sleep did not significantly predict afternoon pain severity while controlling for the effect of morning pain catastrophizing. Greater non-restorative sleep during the previous night and a higher level of morning pain catastrophizing appear to serve as risk factors for experiencing greater daily pain and activity interference later in the day. These findings point to the potential utility of targeted interventions that improve both sleep quality and pain catastrophizing to help individuals with chronic pain engage in important daily activities despite experiencing pain.

Usefulness of Ramp & Hold Procedures for Testing of Pain Facilitation in Human Participants: Comparisons with Temporal Summation of Second Pain.

Quantitative sensory testing (QST) is used to systematically interrogate normal responding and alterations of nervous system function, including pain related central sensitization (CS). However, up to now QST of CS in human subjects has been mostly focused on temporal summation of second pain (TSSP), has been difficult to perform, and has been associated with low reliability. In contrast, slow ramp & hold (RH) procedures are simpler tests of temporal summation and easier to perform. We examined the usefulness of RH procedures as reliable generators of CS using two validated QST procedures: decay of pain aftersensations and wind-down. Twenty-seven pain-free subjects (74% female) were enrolled into the study. Trains of sensitivity adjusted TSSP or RH heat stimuli were applied to the hands of participants to achieve moderate temporal pain summation [50 NRS (0-100)]. Fifteen second aftersensations and 30s wind-down related to TSSP or RH were used for CS comparisons. Reliability of all test procedures was tested over 24 h. Use of sensitivity adjusted TSSP and RH heat stimuli resulted in average pain ratings of 48.2 and 49.6 NRS, respectively. Aftersensations or wind-down decay were not significantly different after either TSSP or RH, (all p > .05), indicating that each procedure achieved similar levels of short-term CS. Sensitivity adjusted RH stimuli were well tolerated and resulted in reliable pain increases of 50 NRS. The magnitude of short-term CS, determined by aftersensations and wind-down was similar after sensitivity-adjusted TSSP and RH stimuli (p > .05), suggesting that pain facilitation of healthy participants and likely chronic pain patients can not only be tested with TSSP but also with RH procedures. Perspective: This article examines the ability of RH procedures to generate similar central sensitivity augmentation than TSSP. The results suggest that RH is similarly well suited as TSSP to explore central pain mechanisms in healthy subjects and most likely also in chronic pain patients.

Effects of Intraoperative Low-Dose Ketamine on Persistent Postsurgical Pain after Breast Cancer Surgery: A Prospective, Randomized, Controlled, Double-Blind Study.

Compared to acute postsurgical pain, studies regarding the role of ketamine in persistent postsurgical pain (PPSP) are limited.

Search