Age and pain differences in non-verbal fluency performance: Associations with cortical thickness and subcortical volumes

Pain in non-communicative older adults beyond dementia: a narrative review

Aging is associated with an increased risk of developing pain, especially in the presence of concurrent chronic clinical conditions. Similarly, multimorbidity can affect the perception and ability of older adults to appropriately respond to and communicate pain, and there is a clinical heterogeneity in the processing of painful sensations in different neurological conditions. The present narrative review is aimed at assessing the prevalent diseases associated with poor communication and pain in older adults, together with the available diagnostic instruments for the clinical assessment of pain in such a vulnerable population. Dementia was the most described pathology identified in the current literature associated with poor communication in older adults affected by pain, along with Parkinson's disease and stroke. Notably, a common pattern of pain behaviors in these neurological disorders also emerged, indicating potential similarities in the clinical presentation and appropriate diagnostic workout. At the same time, there are many differences in the way patients express their pain according to their main neurological pathology. In addition to this, although a plethora of observation-based tools for pain in patients with dementia have been developed, there is no gold standard, and the clinical utility of such measurements is still largely unaddressed. Meanwhile, there is substantially no standardized observation-based tool for pain in non-communicative patients with Parkinson's disease, and only a few for stroke. Overall, the present narrative review provides an update on the prevalent diseases beyond dementia associated with a communicative disability and a painful condition in older adults.

Brain-predicted age difference estimated using DeepBrainNet is significantly associated with pain and function-a multi-institutional and multiscanner study

ABSTRACT

Brain age predicted differences (brain-PAD: predicted brain age minus chronological age) have been reported to be significantly larger for individuals with chronic pain compared with those without. However, a debate remains after one article showed no significant differences. Using Gaussian Process Regression, an article provides evidence that these negative results might owe to the use of mixed samples by reporting a differential effect of chronic pain on brain-PAD across pain types. However, some remaining methodological issues regarding training sample size and sex-specific effects should be tackled before settling this controversy. Here, we explored differences in brain-PAD between musculoskeletal pain types and controls using a novel convolutional neural network for predicting brain-PADs, ie, DeepBrainNet. Based on a very large, multi-institutional, and heterogeneous training sample and requiring less magnetic resonance imaging preprocessing than other methods for brain age prediction, DeepBrainNet offers robust and reproducible brain-PADs, possibly highly sensitive to neuropathology. Controlling for scanner-related variability, we used a large sample (n = 660) with different scanners, ages (19-83 years), and musculoskeletal pain types (chronic low back [CBP] and osteoarthritis [OA] pain). Irrespective of sex, brain-PAD of OA pain participants was ∼3 to 4.7 years higher than that of CBP and controls, whereas brain-PAD did not significantly differ among controls and CBP. Moreover, brain-PAD was significantly related to multiple variables underlying the multidimensional pain experience. This comprehensive work adds evidence of pain type-specific effects of chronic pain on brain age. This could help in the clarification of the debate around possible relationships between brain aging mechanisms and pain.

Pain associates with subjective memory problems and cognition in older Puerto Rican adults

This study examined whether pain is associated with subjective memory problems or cognition in Puerto Rican older adults. Participants came from the Puerto Rican Elderly Health Conditions (PREHCO) study, aged 60 and over (n = 2,144). Analyses examined concurrent and longitudinal associations of pain with subjective memory problems and cognition using a cognitive screener. Overall, participants with pain were more likely to report concurrent subjective memory problems than those without pain. Older adults with pain also exhibited slightly lower concurrent cognition. Novel pain was associated with cognitive decline and greater likelihood of incident subjective memory problems at follow-up. Persistent pain was only related to incident subjective memory problems at follow-up. Pain is associated with cognitive decline and subjective memory problems in older Puerto Ricans. Future studies should implement more in-depth neuropsychological assessments and examine the potential role of barriers to pain management in this population.

Chronic Musculoskeletal Pain Moderates the Association between Sleep Quality and Dorsostriatal-Sensorimotor Resting State Functional Connectivity in Community-Dwelling Older Adults

Aging is associated with poor sleep quality and greater chronic pain prevalence, with age-related changes in brain function as potential underlying mechanisms. Objective. The following cross-sectional study aimed to determine whether self-reported chronic musculoskeletal pain in community-dwelling older adults moderates the association between sleep quality and resting state functional brain connectivity (rsFC). Methods. Community-dwelling older individuals (mean age = 73.29 years) part of the NEPAL study who completed the Pittsburg Sleep Quality Index (PSQI) and a rsFC scan were included (n = 48) in the present investigation. To that end, we tested the effect of chronic pain-by-PSQI interaction on rsFC among atlas-based brain regions-of-interest, controlling for age and sex. Results and Discussion. A significant network connecting the bilateral putamen and left caudate with bilateral precentral gyrus, postcentral gyrus, and juxtapositional lobule cortex, survived global multiple comparisons (FDR; q < 0.05) and threshold-free network-based-statistics. Greater PSQI scores were significantly associated with greater dorsostriatal-sensorimotor rsFC in the no-pain group, suggesting that a state of somatomotor hyperarousal may be associated with poorer sleep quality in this group. However, in the pain group, greater PSQI scores were associated with less dorsostriatal-sensorimotor rsFC, possibly due to a shift of striatal functions toward regulation sensorimotor aspects of the pain experience, and/or aberrant cortico-striatal loops in the presence of chronic pain. This preliminary investigation advances knowledge about the neurobiology underlying the associations between chronic pain and sleep in community-dwelling older adults that may contribute to the development of effective therapies to decrease disability in geriatric populations.

Pain differences in neurite orientation dispersion and density imaging measures among community-dwelling older adults

Neurite orientation dispersion and density imaging (NODDI) is a technique providing more detailed information on the microstructural bases of white matter. Given the previously reported white matter contributions to chronic pain, the present study aims to investigate pain-specific differences in NODDI measures across white matter tracts in a sample of community-dwelling older adults with (n = 29) and without (n = 18) chronic musculoskeletal pain. We further aimed to investigate associations between NODDI measures and clinical and experimental pain measures. As part of the Nepal study, a subset of older adults (>60 years old), underwent multiple laboratory sessions providing self-reported and experimental pain measures and a diffusion weighted neuroimaging sequence. Older adults with chronic musculoskeletal pain had a lower neurite density with less geometric complexity across a number of white matter tracts compared to older pain-free controls (corrected p's < 0.05). Lower neurite density was associated with greater self-reported pain intensity and anatomical pain sites, as well as greater experimental pain sensitivity (p's < 0.05). There were also significant pain-by-sex differences in neurite density and geometric complexity across multiple white matter tracts mainly around the hippocampus (corrected p's < 0.05). Finally, there were no pain differences with respect to extra-cellular water diffusion (corrected p's > 0.05). Our study demonstrates less geometric complexity in neurite density and architecture in chronic musculoskeletal pain, partly in a sex-dependent manner. An increased understanding of neurobiological mechanisms such as those measured by NODDI may contribute to the potential targeting of interventions in our older population suffering from chronic pain.

Pain and the Montreal Cognitive Assessment (MoCA) in Aging

OBJECTIVE

The present study aimed to determine whether specific cognitive domains part of the Montreal Cognitive Assessment (MoCA) are significantly lower in community-dwelling older adults with chronic pain compared with older adults without pain and whether these domains would be associated with self-reported pain, disability, and somatosensory function.

DESIGN

Secondary data analysis, cross-sectional.

SETTING

University of Florida.

SUBJECTS

Individuals over 60 years old enrolled in the Neuromodulatory Examination of Pain and mobility Across the Lifespan (NEPAL) study were included if they completed the MoCA and other study measures (n = 62). Most participants reported pain on most days during the past three months (63%).

METHODS

Subjects underwent a health assessment (HAS) and a quantitative sensory testing (QST) session. Health/medical history, cognitive function and self-reported pain measures were administered during the HAS. Mechanical and thermal detection, and thermal pain thresholds were assessed during the QST session.

RESULTS

Older adults with chronic pain had lower MoCA scores compared with controls on domains of executive function, attention, memory, and language (P < 0.05). The attention and language domains survived adjustments for age, sex, education, depression, and pain duration (P < 0.05). Attention was significantly associated with all pain characteristics including pain intensity and disability, while executive function was associated with mechanical detection (P < 0.05).

CONCLUSION

Our results support previous findings that individuals with chronic pain tend to show poorer cognitive functioning compared with pain-free controls in domains of attention and executive function. Our findings also extend these findings to community-dwelling older adults, who are already most vulnerable to age-related cognitive declines.

Brain gamma-aminobutyric acid, but not glutamine and glutamate levels are lower in older adults with chronic musculoskeletal pain: considerations by sex and brain location

INTRODUCTION AND OBJECTIVES

GABAergic and glutamatergic neurotransmitter systems are central to the pathophysiology of chronic pain and are equally affected by aging processes. We measured levels of frontal gamma-aminobutyric acid (GABA) and the combined resonance of glutamate and glutamine (Glx) in vivo using proton magnetic resonance spectroscopy (1H-MRS) to elucidate age-specific and pain-specific associations with clinical and experimental pain in older adults.

METHODS

Younger (18-24, n = 24) and older (60-94, n = 41) individuals part of a larger study (Neuromodulatory Examination of Pain and Mobility Across the Lifespan [NEPAL]) underwent questionnaires, quantitative sensory testing, and 1H-MRS Mescher-Garwood point-resolved spectroscopy to measure GABA and Glx levels in prefrontal and sensorimotor brain regions.

RESULTS

Older participants had significantly lower sensorimotor, but not prefrontal, GABA and Glx levels, compared with younger controls (P's < 0.05). Younger controls had significantly higher prefrontal and sensorimotor GABA, but not Glx, levels compared with older controls and older adults with chronic pain (P's < 0.05). Older males with chronic pain had significantly lower prefrontal GABA compared with older and younger male controls (P's < 0.05). Prefrontal GABA, but not Glx, was significantly associated with self-reported and experimental pain measures (P's < 0.05). Our results are the first to focus exclusively on age and pain differences in GABA and Glx including younger and older controls to elucidate aging and pain contributions to brain GABAergic and glutamatergic processes.

CONCLUSION

Evaluation of both the neuroinhibitory and neuroexcitatory mechanisms provide promising potential for improving both our understanding of the mechanisms of chronic pain in aging and opportunities for effective, individualized treatments.

Age Differences in Multimodal Quantitative Sensory Testing and Associations With Brain Volume

BACKGROUND AND OBJECTIVES

Somatosensory function is critical for successful aging. Prior studies have shown declines in somatosensory function with age; however, this may be affected by testing site, modality, and biobehavioral factors. While somatosensory function declines are associated with peripheral nervous system degradation, little is known regarding correlates with the central nervous system and brain structure in particular. The objectives of this study were to examine age-related declines in somatosensory function using innocuous and noxious stimuli, across 2 anatomical testing sites, with considerations for affect and cognitive function, and associations between somatosensory function and brain structure in older adults.

RESEARCH DESIGN AND METHODS

A cross-sectional analysis included 84 "younger" (n = 22, age range: 19-24 years) and "older" (n = 62, age range: 60-94 years) healthy adults who participated in the Neuromodulatory Examination of Pain and Mobility Across the Lifespan study. Participants were assessed on measures of somatosensory function (quantitative sensory testing), at 2 sites (metatarsal and thenar) using standardized procedures, and completed cognitive and psychological function measures and structural magnetic resonance imaging.

RESULTS

Significant age × test site interaction effects were observed for warmth detection (p = .018,η p 2 = 0.10) and heat pain thresholds (p = .014,η p 2 = 0.12). Main age effects were observed for mechanical, vibratory, cold, and warmth detection thresholds (ps < .05), with older adults displaying a loss of sensory function. Significant associations between somatosensory function and brain gray matter structure emerged in the right occipital region, the right temporal region, and the left pericallosum.

DISCUSSION AND IMPLICATIONS

Our findings indicate healthy older adults display alterations in sensory responses to innocuous and noxious stimuli compared to younger adults and, furthermore, these alterations are uniquely affected by anatomical site. These findings suggest a nonuniform decline in somatosensation in older adults, which may represent peripheral and central nervous system alterations part of aging processes.

Chronic Pain is Associated With Reduced Sympathetic Nervous System Reactivity During Simple and Complex Walking Tasks: Potential Cerebral Mechanisms

BACKGROUND

Autonomic dysregulation may lead to blunted sympathetic reactivity in chronic pain states. Autonomic responses are controlled by the central autonomic network (CAN). Little research has examined sympathetic reactivity and associations with brain CAN structures in the presence of chronic pain; thus, the present study aims to investigate how chronic pain influences sympathetic reactivity and associations with CAN brain region volumes.

METHODS

Sympathetic reactivity was measured as change in skin conductance level (ΔSCL) between a resting reference period and walking periods for typical and complex walking tasks (obstacle and dual-task). Participants included 31 people with (n = 19) and without (n = 12) chronic musculoskeletal pain. Structural 3 T MRI was used to determine gray matter volume associations with ΔSCL in regions of the CAN (i.e., brainstem, amygdala, insula, and anterior cingulate cortex).

RESULTS

ΔSCL varied across walking tasks (main effect p = 0.036), with lower ΔSCL in chronic pain participants compared to controls across trials 2 and 3 under the obstacle walking condition. ΔSCL during typical walking was associated with multiple CAN gray matter volumes, including brainstem, bilateral insula, amygdala, and right caudal anterior cingulate cortex (p's < 0.05). The difference in ΔSCL from typical-to-obstacle walking were associated with volumes of the midbrain segment of the brainstem and anterior segment of the circular sulcus of the insula (p's < 0.05), with no other significant associations. The difference in ΔSCL from typical-to-dual task walking was associated with the bilateral caudal anterior cingulate cortex, and left rostral cingulate cortex (p's < 0.05).

CONCLUSIONS

Sympathetic reactivity is blunted during typical and complex walking tasks in persons with chronic pain. Additionally, blunted sympathetic reactivity is associated with CAN brain structure, with direction of association dependent on brain region. These results support the idea that chronic pain may negatively impact typical autonomic responses needed for walking performance via its potential impact on the brain.

Cortical Thickness Mediates the Association Between Self-Reported Pain and Sleep Quality in Community-Dwelling Older Adults

INTRODUCTION

Musculoskeletal pain is prevalent in older adults representing the leading cause of disability in this population. Similarly, nearly half of older adults complain of difficulty sleeping. We aimed to explore the relationship between sleep quality with self-reported musculoskeletal pain, somatosensory and pain thresholds in community-dwelling older adults and further explore brain regions that may contribute to this association.

METHODS

Older adults (>60 years old, n=69) from the NEPAL study completed demographic, pain and sleep assessments followed by a quantitative sensory testing battery. A subset (n=49) also underwent a 3T high-resolution, T1-weighted anatomical scan.

RESULTS

Poorer sleep quality using the Pittsburgh Sleep Quality Index was positively associated with self-reported pain measures (all p's >0.05), but not somatosensory and pain thresholds (all p's >0.05). Using a non-parametric threshold-free cluster enhancement (TFCE) approach, worse sleep quality was significantly associated with lower cortical thickness in the precentral, postcentral, precuneus, superior parietal, and lateral occipital regions (TFCE-FWE-corrected at p < 0.05). Further, only postcentral cortical thickness significantly mediated the association between sleep quality and self-reported pain intensity using bootstrapped mediation methods.

CONCLUSION

Our findings in older adults are similar to previous studies in younger individuals where sleep is significantly associated with self-reported pain. Specifically, our study implicates brain structure as a significant mediator of this association in aging. Future larger studies are needed to replicate our findings and to further understand if the brain can be a therapeutic target for both improved sleep and pain relief in older individuals.

A Biopsychosocial Model of Chronic Pain for Older Adults

Population

Comprehensive evaluation of chronic pain in older adults is multifaceted.

Objective and Methods

Research on chronic pain in older adults needs to be guided by sound conceptual models. The purpose of this paper is to describe an adaptation of the Biopsychosocial Model (BPS) of Chronic Pain for older adults. The extant literature was reviewed, and selected research findings that provide the empiric foundation for this adaptation of the BPS model of chronic pain are summarized. The paper concludes with a discussion of specific recommendations for how this adapted model can be used to guide future research.

Conclusions

This adaptation of the BPS model of chronic pain for older adults provides a comprehensive framework to guide future research in this vulnerable population.