A Cross-Sectional Study of Pain Sensitivity and Unpleasantness in People with Vascular Dementia

Pharmacological treatment of pain, dyspnea, death rattle, fever, nausea, and vomiting in the last days of life in older people: A systematic review

BACKGROUND

Evidence based guidelines for treatment of physical symptoms during the last days of life in older people are not available.

AIM

We wanted to synthesize the existing evidence on the pharmacological treatment of pain, dyspnea, death rattle, fever, nausea, and vomiting during the last days of life in older people to develop recommendations that can help guide clinical practice.

DESIGN

A systematic review was conducted (PROSPERO #CRD42023406100) and reported in accordance with PRISMA guidelines.

DATA SOURCES

MEDLINE and EMBASE were searched from inception till March 2023, together with national and international guideline databases.

RESULTS

Four predominantly descriptive studies on opioid use were included for the treatment of pain and four for dyspnea, without clear evidence for the choice of one specific opioid, nor a specific opioid dose. For death rattle, five randomized controlled trials and two retrospective studies were included. These provide evidence for the prophylactic treatment of death rattle with hyoscine butylbromide. For fever, nausea, and vomiting, no articles met the inclusion criteria.

CONCLUSION

Limited evidence exists to guide the pharmacological treatment of pain, dyspnea, death rattle, fever, nausea, and vomiting in the last days of life of older people. Other than the use of opioids for treatment of pain and dyspnea and prophylactic administration of hyoscine butylbromide to decrease the likelihood of developing death rattle, no specific recommendations can be formulated for use in clinical practice. This demonstrates the challenging nature of research in the last days of life of older people, despite its pressing need.

The association between cognitive ability and opioid prescribing in vulnerable older adults with chronic pain in ambulatory care: a secondary data analysis using the Medical Expenditure Panel Survey

BACKGROUND

Vulnerable older adults living with Alzheimer's disease or Alzheimer's disease and related dementia (AD/ADRD) and chronic pain generally receive fewer pain medications than individuals without AD/ADRD, especially in nursing homes. Little is known about pain management in older adults with AD/ADRD in the community. The aim of the study was to examine opioid prescribing patterns in individuals with chronic pain by levels of cognitive ability in ambulatory care.

METHODS

We used the Medical Expenditure Panel Survey (MEPS), years 2002-2017, and identified three levels of cognitive impairment: no cognitive impairment (NCI), individuals reporting cognitive impairment (CI) without an AD/ADRD diagnosis, and individuals with a diagnosis of AD/ADRD. We examined any receipt of an opioid prescription and the number of opioid prescriptions using a logistic and negative binomial regression adjusting for sociodemographic and health characteristics and stratifying by three types of chronic pain (any chronic pain, severe chronic pain, and chronic pain identified through ICD 9/10 chronic pain diagnoses).

RESULTS

Among people with any chronic pain, adjusted odds of receiving an opioid for people with CI (OR 1.41, 95% confidence interval 1.31-1.52) and AD/ADRD (OR 1.23, 95% confidence interval 1.04-1.45) were higher compared to NCI. Among people with chronic pain ICD 9/10 conditions, the odds of receiving an opioid were also higher for those with CI (OR 1.43, 95% confidence interval 1.34-1.56) and AD/ADRD (OR 1.48, 95% confidence interval 1.23-1.78) compared to NCI. Among those with severe chronic pain, people with CI were more likely to receive an opioid (OR 1.17, 95% confidence interval 1.07-1.27) relative to NCI (OR 0.89, 95% confidence interval 0.75-1.06). People with AD/ADRD experiencing severe chronic pain were not more likely to receive an opioid compared to the NCI group. Adjusted predicted counts of opioid prescriptions showed more opioids in CI and AD/ADRD in all chronic pain cohorts, with the largest numbers of opioid prescriptions in the severe chronic pain and ICD 9/10 diagnoses groups.

CONCLUSIONS

The results suggest increased opioid use in people living with CI and AD/ADRD in the ambulatory care setting and potentially indicate that these individuals either require more analgesics or that opioids may be overprescribed. Further research is needed to examine pain management in this vulnerable population.

Abnormal Spontaneous Discharges of Primary Sensory Neurons and Pain Behavior in a Rat Model of Vascular Dementia

Patients with vascular dementia experience more pain than healthy elders, potentially due to the presence of central neuropathic pain. However, the mechanisms underlying neuropathic pain in vascular dementia remain poorly understood, and there is currently a lack of effective treatment available. In this study, a rat model of vascular dementia was induced by permanently occluding the common carotid arteries bilaterally (2-VO). The cognitive impairments in the 2-VO rats were evaluated using the Morris Water Maze test, while HE and LBF staining were employed to assess brain tissue lesions in the hippocampal, cerebral cortex, and white matter regions known to be associated with severe memory and learning deficits. Furthermore, pain-related behavioral tests, including mechanical and thermal stimuli assessments, were conducted, and in vivo electrophysiological recordings of primary sensory neurons were performed. Compared to sham-operated and pre-operative rats, rats with vascular dementia exhibited mechanical allodynia and thermal hyperalgesia 30 days after surgery. Furthermore, in vivo electrophysiology revealed a significant increase in the occurrence of spontaneous activity of Aβ- and C-fiber sensory neurons in the rat model of vascular dementia. These results indicate that neuropathic pain behaviors developed in the rat model of vascular dementia, and abnormal spontaneous discharges of primary sensory neurons may play a crucial role in the development of pain after vascular dementia.

Long-term follow-up of intracerebroventricular injection of streptozotocin-inducing pain sensitization

Age is known to be the major risk factor for both pain sensation and sporadic Alzheimer's disease (sAD). Pain management in AD is a critical health condition. However, assessing pain in sAD patients is challenging. The intracerebroventricularly injected streptozotocin (icv-STZ) rat model of sAD has been brought to the fore as a hopefully suitable model that could mimic some features of sAD. However, the exact mechanism by which this agent may induce AD-like pathology is largely unknown. In some studies, analgesic drugs have been suggested as possible prevention of AD and icv-STZ-induced AD-like pathology. Therefore, this study used formalin and tail-flick tests to investigate whether different doses of icv-STZ injections could affect acute and inflammatory pain sensation and edema volume over time. Behavioral responses were observed at four testing time points (1, 2.5, 3.5, and 6 months postinjection). The results indicate that icv-STZ was able to significantly decrease the animals' formalin pain threshold in both a time- and dose-dependent manner. Formalin-induced acute and chronic pain scores of animals treated with streptozotocin 3 mg/kg (STZ3) increased dramatically 2.5 months after injection and persisted thereafter. The augmentation in pain score induced by streptozotocin 1 mg/kg (STZ1) was observed from 3.5 months after STZ injection. However, the effect of streptozotocin 0.5 mg/kg (STZ0.5) was NS until 6 months after injection. However, formalin-induced paw edema occurred with a longer delay and was not detectable in STZ0.5-treated animals. In addition, only STZ3-treated animals significantly reduced the thermal pain threshold of animals 6 months after injection. These observations indicate that icv-STZ can sensitize central and/or peripheral receptors to pain. The effect of STZ is dose- and time-dependent. AD-like pathology induced by icv-STZ could be partially activated via pain processing pathways. Therefore, anti-inflammatory agents could alleviate AD-like symptoms via pain treatments.