Human Studies

In this observational study, using the Global Burden of Disease and Risk Factors Study, we aimed to (i) report the magnitude of health loss due to non-communicable neurological disorders in the USA in 2017 by sex, age, years and States and (ii) to identify non-communicable neurological disorders attributable environmental, metabolic and behavioural risk factors. We provide estimates of the burden of non-communicable neurological disorders by reporting disability-adjusted life-years and their trends from 1990 to 2017 by age and sex in the USA. The non-communicable neurological disorders include migraines, tension-type headaches, multiple sclerosis, Alzheimer's disease and other dementias, Parkinson's disease, epilepsy, motor neuron diseases and other neurological disorders. In 2017, the global burdens of non-communicable neurological disorders were 1444.41 per 100 000, compared to the USA burden of 1574.0. Migraine was the leading age-standardized disability-adjusted life-years 704.7 per 100 000, with Alzheimer's disease and other dementias (41.8.7), and epilepsy (123.8) taking the second and third places, respectively. Between 1990 and 2017, the age-standardized disability-adjusted life-years rates for aggregate non-communicable neurological disorders relative to all cause increased by 3.42%. More specifically, this value for motor neuron diseases, Parkinson's disease and multiple sclerosis increase by 20.9%, 4.0%, 2.47%, 3.0% and 1.65%, respectively. In 2017, the age-standardized disability-adjusted life-years rates for the aggregate non-communicable neurological disorders was significantly higher in females than the males (1843.5 versus 1297.3 per 100 000), respectively. The age-standardized disability-adjusted life-years rates for migraine were the largest in both females (968.8) and males were (432.5) compared to other individual non-communicable neurological disorders. In the same year, the leading non-communicable neurological disorders age-standardized disability-adjusted life-years rates among children ≤9 was epilepsy (216.4 per 100 000). Among the adults aged 35-60 years, it was migraine (5792.0 per 100 000), and among the aged 65 and above was Alzheimer's disease and other dementias (78 800.1 per 100 000). High body mass index, smoking, high fasting plasma glaucous and alcohol use were the attributable age-standardized disability-adjusted life-years risks for aggregate and individual non-communicable neurological disorders. Despite efforts to decrease the burden of non-communicable neurological disorders in the USA, they continue to burden the health of the population. Children are most vulnerable to epilepsy-related health burden, adolescents and young adults to migraine, and elderly to Alzheimer's disease and other dementias and epilepsy. In all, the most vulnerable populations to non-communicable neurological disorders are females, young adults and the elderly.

Dysmenorrhea is a common disorder that substantially disrupts the lives of young women. To determine whether there is evidence of activation of the innate immune system in dysmenorrhea and whether the degree of activation may be used as a biomarker for pain, we compared the responsiveness of peripheral blood mononuclear cells (PBMCs) to toll-like receptor (TLR) 2 or 4 stimulation. We also investigated whether this effect is modulated by the use of the oral contraceptive pill (OC).

Low back pain (LBP) is the most common cause of chronic pain. Numerous clinical scales are available for evaluating pain, but their objective criteria in the management of LBP patients remain unclear. This study aimed to determine an objective cutoff value for a change in the Pain Intensity Numerical Rating Scale (ΔPI-NRS) three months after LBP treatment. Its utility was compared with changes in six commonly used clinical scales in LBP patients: Pain Disability Assessment Scale (PDAS), Pain Self-Efficacy Questionnaire (PSEC), Pain Catastrophizing Scale (PCS), Athens Insomnia Scale (AIS), EuroQoL 5 Dimension (EQ5D), and Locomo 25. We included 161 LBP patients treated in two representative pain management centers. Patients were partitioned into two groups based on patient's global impression of change (PGIC) three months after treatment: satisfied (PGIC = 1, 2) and unsatisfied (3-7). Multivariate logistic regression analysis was performed to explore relevant scales in distinguishing the two groups. We found ΔPI-NRS to be most closely associated with PGIC status regardless of pre-treatment pain intensity, followed by ΔEQ5D, ΔPDAS, ΔPSEC, and ΔPCS. The ΔPI-NRS cutoff value for distinguishing the PGIC status was determined by ROC analysis to be 1.3-1.8 depending on pre-treatment PI-NRS, which was rounded up to ΔPI-NRS = 2 for general use. Spearman's correlation coefficient revealed close relationships between ΔPI-NRS and the six other clinical scales. Therefore, we determined cutoff values of these scales in distinguishing the status of ΔPI-NRS≥2 vs. ΔPI-NRS<2 to be as follows: ΔPDAS, 6.71; ΔPSEC, 6.48; ΔPCS, 6.48; ΔAIS, 1.91; ΔEQ5D, 0.08; and ΔLocomo 25, 9.31. These can be used as definitive indicator of therapeutic outcome in the management of chronic LBP patients.

Chronic pain has been associated with alterations in brain structure and function that appear dependent on pain phenotype. Functional connectivity (FC) data on chronic back pain (CBP) is limited and based on heterogeneous pain populations. We hypothesize that failed back surgery syndrome (FBSS) patients being considered for spinal cord stimulation (SCS) therapy have altered resting state (RS) FC cross-network patterns that 1) specifically involve emotion and reward/aversion functions and 2) are related to pain scores.