Pain and sleep : A bidirectional relationship

Chronic Pain Characteristics and Interference With Daily Activities in Patients Undergoing Hemodialysis: A Cross-Sectional Study

PURPOSE

Few studies have analyzed the characteristics of chronic pain and its functional interference. This study aims to measure the prevalence of pain and assess the intensity, location, treatments used and functional interference in the daily living of patients with chronic pain undergoing hemodialysis treatments in Morocco.

DESIGN

This research has a descriptive cross-sectional design METHODS: A multicenter study was performed in four public hemodialysis centers in Morocco's northern region including 174 patients undergoing hemodialysis. Sociodemographic, chronic pain and interference were evaluated through a structured questionnaire, the Visual Analog Scale and the Brief Pain Inventory.

RESULTS

Descriptive statistics were applied to data analysis. The prevalence of chronic pain was 56.7%, severe in 50.6% of cases and 81.6% experienced continuous pain. The most common pain locations among patients undergoing hemodialysis were the lower limbs 58.6%, back 41.4% and hips 36.4%. Therefore, a high prevalence of severe functional interference of pain has been found in walking 60.34%, general activities 52.87% and work 48.85%. Additionally, analgesics were used by 73.6% of patients, with 46.1% of instances involving frequent use and relief for 32.81%.

CONCLUSIONS

Chronic pain is prevalent, undertreated and localized in the lower limbs, back and hips, leading to severe interference with functional activities.

CLINICAL IMPLICATIONS

This evidence makes professionals aware of their patient's pain and its impact, and consequently, their assessment must be conducted in a primordial and regular manner to improve management. Pain management can be based on pharmacological approaches such as opioids as well as nonpharmacological approaches.

Improving Anxiety Related to Chronic Pain Through a Sleep Circadian Intervention Program: A Pilot Study

The limitations of pharmacological treatments for chronic pain have become increasingly evident: dependency, side effects, resistance, and diminishing efficacy. The urgent need for innovative solutions has become a compelling focus for improving patient outcomes. Innovative non-pharmacological approaches, such as sleep management, as a strategy to reduce opioid consumption and pain control are needed. The aim was to evaluate the impact of a Sleep and Circadian Intervention Program (SCIP) in the control of chronic musculoskeletal pain (CMP). This was a randomized clinical trial (NCT03646084), in which 49 CMP patients were assigned to SCIP (n = 15, mean age 51 years and 40% women) or non-SCIP groups (n = 26, 53 years and 61.5% women). Outcomes were evaluated after 6 months through self-reported questionnaires (pain intensity, physical function, depression/anxiety, and quality of life (QoL)). The SCIP group was assessed by polysomnography and specific questionnaires and was treated for diagnosed sleep disorders according to clinical guidelines. This population showed a moderate pain intensity at baseline, important deterioration of QoL and pathological anxiety/fear related to pain. Fifty percent of them presented restless leg syndrome, 60% moderate/severe insomnia, and 62.5% sleep apnea. During the follow-up, the SCIP group presented a greater reduction in the abnormal risk group for anxiety (from 73.3% to 46.7%) and depression (from 53.3% to 33.3%) on the Hospital Anxiety and Depression Scale compared to the non-SCIP group (from 40% to 29.2% and 33.3% to 29.2%, respectively). Also, a positive significant effect on anxiety/fear related to pain was found in the Pain Anxiety Symptoms Scale multivariable model, with an important improvement in symptoms. The application of SCIP in CMP patients improved anxiety and controlled associated sleep disorders, highlighting the impact on insomnia. Larger studies are needed for better understanding of the sleep intervention in CMP control.

Analysis of the factors influencing of sleep quality in intensive care unit awake patients based on a structural equation model: A cross-sectional study

OBJECTIVE

The objective of this study was to construct and validate a structural equation model (SEM) to identify factors associated with sleep quality in awake patients in the intensive care unit (ICU) and to assist in the development of clinical intervention strategies.

RESEARCH METHODS/SETTING

In this cross-sectional study, 200 awake patients who were cared for in the ICU of a tertiary hospital in China were surveyed via several self-report questionnaires and wearable actigraphy sleep monitoring devices. Based on the collected data, structural equation modelling analysis was performed using SPSS and AMOS statistical analysis software. The study is reported using the STROBE checklist.

RESULTS

The fit indices of the SEM were acceptable: χ2/df = 1.676 (p < .001) and RMSEA = .058 (p < 0.080). Anxiety/depression had a direct negative effect on the sleep quality of awake patients cared for in the ICU (β = -.440, p < .001). In addition, disease-freeness progress had an indirect negative effect on the sleep quality of awake patients cared for in the ICU (β = -.142, p < .001). Analgesics had an indirect negative effect on the sleep quality of awake patients cared for in the ICU through pain and sedatives (β = -.082, p < .001). Sedation had a direct positive effect on the sleep quality of conscious patients cared for in the ICU (β = .493; p < .001).

CONCLUSION

The results of the SEM showed that the sleep quality of awake patients cared for in the ICU is mainly affected by psychological and disease-related factors, especially anxiety, depression and pain, so we can improve the sleep quality of patients through psychological intervention and drug intervention.

Cognitive behavioral therapy for insomnia in people with chronic musculoskeletal pain. A systematic review and dose-response meta-analysis

The aims were (i) to determine the effects of Cognitive behavioral therapy for insomnia (CBT-I) on sleep disturbances, pain intensity and disability in patients with chronic musculoskeletal pain (CMP), and (ii) to determine the dose-response association between CBT-I dose (total minutes) and improvements in sleep disorders, pain intensity and disability in patients with CMP. A comprehensive search was conducted in PubMed/MEDLINE, Web of Science, CINAHL, and SCOPUS until December 17, 2023. Randomized clinical trials (RCTs) using CBT-I without co-interventions in people with CMP and sleep disorders were eligible. Two reviewers independently extracted data and assessed risk of bias and certainty of the evidence. A random effects meta-analysis was applied to determine the effects on the variables of interest. The dose-response association was assessed using a restricted cubic spline model. Eleven RCTs (n = 1801 participants) were included. We found a significant effect in favor of CBT-I for insomnia (SMD: -1.34; 95%CI: -2.12 to -0.56), with a peak effect size at 450 min of CBT-I (-1.65, 95%CI: -1.89 to -1.40). A non-significant effect was found for pain intensity. A meta-analysis of disability was not possible due to the lack of data. This review found benefits of CBT-I for insomnia compared to control interventions, with a large effect size. In addition, it was estimated that a 250-min dose of CBT-I had a large effect on reducing insomnia and that the peak effect was reached at 450 min. These novel findings may guide clinicians in optimizing the use of CBT-I in people with CMP and insomnia.

[Quality of life and sleep quality in patients with chronic pruritus]

Pruritus is defined as a symptom that leads to scratching. Clinically, a heterogeneous group of clinical pictures of different etiology must be considered. Pruritus is characterized by varying intensity and duration. Many patients and/or their social environment, which is influenced by this, cite the impact on sleep quality as an accompanying main symptom. The patient's quality of life is affected depending on the severity of the pruritus and often leads to comorbidity such as depressive disorders or sleep disorders as well as to an impact on psychosocial well-being if it becomes chronic. To date, in addition to the medical history, the established examination methods have been the determination of the disease burden by assessing disease activity, e.g., with validated disease-specific scores, plus the assessment of quality of life using a dermatological quality of life index (DLQI). The latest studies show that this is by no means sufficient to determine the severity of disease and, as a result, to identify adequate treatment options.

Predictors of sleep quality components in patients undergoing transarterial chemoembolisation: a cross-sectional study

PURPOSE

Patients undergoing transarterial chemoembolisation experience postembolisation symptoms and interferences affecting sleep quality, which require intervention. The study aimed to identify the predictors of sleep quality components in patients undergoing transarterial chemoembolisation.

METHODS

This study included two groups of participants: 50 patients undergoing transarterial chemoembolisation and 45 nurses caring for them. Data were collected from September to November 2022 using a structured questionnaire, and analysed using descriptive statistics, the t-test, analysis of variance, Spearman's rank correlation, and multiple regression analysis using the SPSS 27.0 program (IBM Corp., Armonk, NY, USA).

RESULTS

The mean sleep quality score was 40.28±14.10. Heat sensation (t=-2.08, p=.043) and fatigue (t=-4.47, p<.001) predicted sleep fragmentation in 38.6% of the patients. Abdominal pain (t=-2.54, p=.014), vomiting (t=-2.21, p=.032), and the expected fatigue by the nurses (t=2.68, p=.014) predicted sleep length in 41.7% of patients. Abdominal pain (t=-2.05, p=.046) explained 42.9% of sleep depth.

CONCLUSION

Based on the predictors of sleep quality components obtained in this study, strategies to improve sleep quality tailored to patients undergoing transarterial chemoembolisation should be developed. This study highlighted the need to bridge the gap between patients' and nurses' expected fatigue and its contribution to sleep fragmentation and sleep length. It also highlighted the importance of noncontact temperature measurement, controlling vomiting, and pain relief for improving sleep length in patients undergoing transarterial chemoembolisation.

Expressed Beliefs about the Cause of Pain in a Pediatric Population: A Qualitative Study

(1) Background: The aims of this study are to explore what beliefs children and adolescents manifest about the cause of the pain they describe, to compare whether there are differences between beliefs by age and the persistence of pain, and to relate the explanations of the cause of pain with current scientific evidence. (2) Methods: a cross-sectional qualitative study was used. The primary endpoint of the study was obtaining explanations of the cause of pain recorded by means of an open-ended question. The participants were school-age children attending a charted school in the province of Barcelona. (3) Results: The children and adolescents proposed a diverse range of explanations for the cause of pain that they reported in their responses. The most frequent explanation for the cause of pain were pathologies and injuries (45.95%), ergonomic issues (22.60%) and psychological issues (15.95%). (4) Conclusions: There is a lot of variety in the explanations that young people give about the cause of their pain in schoolchildren aged between 10 and 16 years old. There exists a high prevalence of explanations non-associated with tissue damage (ENAD) concerning the causes of pain described. It is necessary that future health prevention programs dedicated to early ages consider which beliefs about the cause of pain are the most frequent in the pediatric population.

Sleep hygiene strategies for individuals with chronic pain: a scoping review

OBJECTIVES

Up to a quarter of the world's population experience chronic pain, which, in addition to interfering with daily activities and waking function, is often associated with poor sleep. Individuals experiencing poor sleep are often encouraged to implement sleep hygiene strategies. However, current sleep hygiene strategies have not been developed considering the unique challenges faced by individuals with chronic pain and therefore they might not be as effective in this population. The aim of this scoping review is to map the state of the existing literature examining sleep hygiene strategies in individuals with chronic pain.

DESIGN

This scoping review included a search of four online databases (Medline, Embase, PsycINFO and CINAHL) to identify articles examining the use of sleep hygiene strategies in populations with chronic pain.

RESULTS

Thirty articles investigated at least one sleep hygiene strategy in individuals with chronic pain, with improvements to sleep reported for six sleep hygiene strategies (education, exercise, limiting alcohol use, limiting tobacco use, prebed state and sleep environment). However, the timing of these strategies was often not reported which limits the degree to which these strategies can be generalised for use as a presleep strategy.

CONCLUSION

This scoping review examined the existing literature focusing on sleep hygiene strategies for people with chronic pain. There are limitations to the methodology of the existing literature and gaps in our understanding of sleep hygiene strategies in some chronic pain conditions that must be addressed in future research before the effectiveness of these strategies can be understood.

Assessment and management of pain/nociception in patients with disorders of consciousness or locked-in syndrome: A narrative review

The assessment and management of pain and nociception is very challenging in patients unable to communicate functionally such as patients with disorders of consciousness (DoC) or in locked-in syndrome (LIS). In a clinical setting, the detection of signs of pain and nociception by the medical staff is therefore essential for the wellbeing and management of these patients. However, there is still a lot unknown and a lack of clear guidelines regarding the assessment, management and treatment of pain and nociception in these populations. The purpose of this narrative review is to examine the current knowledge regarding this issue by covering different topics such as: the neurophysiology of pain and nociception (in healthy subjects and patients), the source and impact of nociception and pain in DoC and LIS and, finally, the assessment and treatment of pain and nociception in these populations. In this review we will also give possible research directions that could help to improve the management of this specific population of severely brain damaged patients.

How Hospital Patients Experience Pain the Previous 24 Hours-A Prevalence Assessment of Pain in Five Hospitals in Sweden

BACKGROUND

Previous studies show that pain is common among hospital inpatients.

AIM

This study measures the prevalence of pain and the impact of pain on sleep in patients admitted to five hospitals in Sweden.

METHODS

The patients were admitted to a surgical or a medical ward. They answered on a self-reported questionnaire about their average pain intensity and how much their pain interfered with their sleep the previous 24 hours, on a 010 numerical rating scale (NRS).

RESULTS

Of the 500 patients, 308 experienced pain (62%), (NRS ≥ 3) and 111 (22%) rated their pain as NRS ≥ 7. We found no difference between surgical and medical specialty regarding pain prevalence. The results suggest that roughly the same proportion of patients with pain also experienced poor sleep due to pain265 patients (53%) reported pain interference on sleep, NRS ≥ 3.

CONCLUSIONS AND CLINICAL IMPLICATIONS

This study shows that there is still an unacceptable high pain prevalence in inpatients and that patients experience pain as negatively impacting their sleep. Future pain care is likely to include a more comprehensive implementation strategy for the dissemination of knowledge, especially related to the complex context of today's healthcare system. That is, the possibility that anchoring new knowledge also benefits the patient is probably associated with optimization of the structural context. Future research should take this question further by examining how the organizational structure should be optimized for the dissemination of knowledge in healthcare professionals about pain and pain interference with sleep.

Effects of methadone, buprenorphine, and naltrexone on actigraphy-based sleep-like parameters in male rhesus monkeys

Opioid use disorder (OUD) has been associated with the emergence of sleep disturbances. Although effective treatments for OUD exist, evidence suggests that these treatments also may be associated with sleep impairment. The extent to which these effects are an effect of OUD treatment or a result of chronic opioid use remains unknown. We investigated the acute effects of methadone, buprenorphine, and naltrexone on actigraphy-based sleep-like parameters in non-opioid-dependent male rhesus monkeys (Macaca mulatta, n = 5). Subjects were fitted with actigraphy monitors attached to primate collars to measure sleep-like parameters. Actigraphy recordings were conducted under baseline conditions, or following acute injections of vehicle, methadone (0.03-1.0 mg/kg, i.m.), buprenorphine (0.01-1.0 mg/kg, i.m.), or naltrexone (0.03-1.0 mg/kg, i.m.) in the morning (4 h after "lights on") or in the evening (1.5 h before "lights off"). Morning and evening treatments with methadone or buprenorphine significantly increased sleep latency and decreased sleep efficiency. The effects of buprenorphine on sleep-like measures resulted in a biphasic dose-response function, with the highest doses not disrupting actigraphy-based sleep. Buprenorphine induced a much more robust increase in sleep latency and decrease in sleep efficiency compared to methadone, particularly with evening administration, and detrimental effects of buprenorphine on sleep-like measures were observed up to 25.5 h after drug injection. Treatment with naltrexone, on the other hand, significantly improved sleep-like measures, with evening treatments improving both sleep latency and sleep efficiency. The currently available pharmacotherapies for OUD significantly alter sleep-like parameters in non-opioid-dependent monkeys, and opioid-dependent mechanisms may play a significant role in sleep-wake regulation.

Assessment of sleep disturbance in oral lichen planus and validation of PSQI: A case-control multicenter study from the SIPMO (Italian Society of Oral Pathology and Medicine)

BACKGROUND

The wellbeing of oral lichen planus patients (OLPs) may be strongly influenced by a poor quality of sleep (QoS) and psychological impairment. The aims were to analyze the prevalence of sleep disturbance, anxiety, and depression in OLPs and to validate the Pittsburgh Sleep Quality Index (PSQI) in OLPs.

METHODS

Three hundred keratotic OLPs (K-OLPs), 300 with predominant non-keratotic OLP (nK-OLPs), and 300 controls were recruited in 15 Italian universities. The PSQI, Epworth Sleepiness Scale (ESS), Hamilton Rating Scales for Depression and Anxiety (HAM-D and HAM-A), Numeric Rating Scale (NRS), and Total Pain Rating Index (T-PRI) were administered.

RESULTS

Oral lichen planus patients had statistically higher scores than the controls in the majority of the PSQI sub-items (p-values < 0.001**). Moreover, OLPs had higher scores in the HAM-D, HAM-A, NRS, and T-PRI (p-values < 0.001**). No differences in the PSQI sub-items' scores were found between the K-OLPs and nK-OLPs, although nK-OLPs suffered from higher levels of anxiety, depression, and pain (p-values: HAM-A, 0.007**, HAM-D, 0.009**, NRS, <0.001**, T-PRI, <0.001**). The female gender, anxiety, depression (p-value: 0.007**, 0.001**, 0.020*) and the intensity of pain, anxiety, and depression (p-value: 0.006**, <0.001**, 0.014*) were independent predictors of poor sleep (PSQI > 5) in K-OLPs and nK-OLPs, respectively. The PSQI's validation demonstrated good internal consistency and reliability of both the total and subscale of the PSQI.

CONCLUSIONS

The OLPs reported an overall impaired QoS, which seemed to be an independent parameter according to the regression analysis. Hence, clinicians should assess QoS in OLPs and treat sleep disturbances in order to improve OLPs management.

A polysomnographic study of sleep disruptions in individuals with chronic neck pain

Various lines of evidence suggest that a bidirectional relationship exists between poor sleep quality and chronic pain, with each condition tending to promote and exacerbate the other. This has led to the hypothesis that the two conditions may be linked by common underlying mechanisms. It has thus been suggested that inadequate sleep and chronic pain may share neurophysiological and molecular pathways that are similar or overlapping. Some studies based on self-report measures have tended to support the inference that chronic neck pain may promote sleep disturbance, but this association has not, until now, been investigated with quantitative measures. The present study is the first to evaluate the sleep quality of patients with chronic neck pain through the use of polysomnography. The study sought to identify the sleep characteristics of patients with chronic neck pain and then to determine whether these characteristics were associated with the severity of their neck pain. Laboratory testing with polysomnography was carried out on 32 males who had complaints of chronic neck pain and on 12 healthy participants who served as controls. Compared to the control subjects, patients with chronic neck pain were found to have significantly shorter times spent in sleep (p = 0.015), longer latencies to sleep onset (p = 0.015) and rapid eye movement (REM) sleep (p < 0.05), longer durations spent in Stage 1 (p < 0.05), and shorter durations spent in both Stage 2 (p = 0.001) and REM sleep (p = 0.00). The severity of discomfort was related negatively to the amount of time spent in REM sleep. The present study's quantitative measures corroborate the view that patients with chronic neck pain have poor sleep quality. These findings confirm long-held clinical observations that the sleep quality of patients with chronic neck pain is compromised, and that, in this clinical group, poor sleep is at least a correlate of and may be an amplifier of perceived pain.

Exploring the feasibility and acceptability of a sleep wearable headband among a community sample of chronic pain individuals: An at-home observational study

Background

Chronic pain conditions affect up to one third of the adult population in the United Kingdom. Sleep problems are prevalent and negatively impact quality of life. Lack of standardised tools for routine screening and assessment of sleep changes have been a barrier for sleep management. Novel sleep wearables offer an exciting and accessible way to measure sleep but have not been tested outside of the consumer-led landscape and are not commonly used in research and clinical settings.

Aims

The study aimed to explore the feasibility and acceptability of a sleep monitoring headband (Dreem 2) utilising EEG technology and accompanying smartphone application among a cohort of adults with chronic pain.

Results

Twenty-one adults (81% women) completed a one-week home sleep study using a sleep headband and accompanying app. Ninety per cent of participants met the pre-defined requirement of two-night's sleep recording. All participants recorded one night of sleep data via the sleep headband. The majority (76%) of participants were satisfied with the sleep study, and 86% of participants were willing to wear the headband longer than the 2-night minimum requirement. Finally, 76% reported the headband as 'somewhat' or 'extremely' comfortable whist awake; 57% rated the headband as comfortable during sleep.

Conclusion

The Dreem 2 headband appears to be a feasible and acceptable means of collecting sleep measurements among individuals with chronic pain, despite common sleep disturbances. These devices may have utility for screening, assessment and monitoring in research and practice. Further research is needed to provide guidelines and training for integration.

The association of sleep disturbances with burning mouth syndrome: An overlooked relationship-A qualitative systematic review

OBJECTIVES

To review the relevant literature to assess whether patients with burning mouth syndrome (BMS) are more prone to have sleep disturbances than general population.

METHODS

The literature search for relevant articles was from July 2020 to March 2021. A systematic search of PubMed, Embase, Google Scholar, Cochrane library, Dentistry & Oral Sciences Source, and Scopus was conducted to search for relevant studies. The quality of studies was assessed in accordance with the Joanna Briggs Institute's guidelines and using the software SUMARI-The System for the Unified Management, Assessment and Review of Information. Confidence in the findings was assessed using the GRADE-CERQual approach.

RESULTS

A total of 1064 studies were initially identified from the search; six studies, two cross-sectional and four case-control, met the inclusion criteria and were selected for this systematic review. Sleep disturbances were a required outcome measured in selected studies evaluating symptoms of BMS. For studies that were included in the final analyses, BMS was found to relate to several dimensions of sleep including sleep disturbance and duration (n = 6), sleep affecting daytime function (n = 4), sleep quality (n = 6), sleep efficiency (n = 4), and ability to fall asleep (n = 4). Consistent evidence of moderate confidence found that BMS was associated with greater sleep disturbance, reduced sleep quality, increased time taken to fall asleep, reduced sleep efficiency, and poor daytime function, whereas evidence of low confidence was found regarding the association of BMS with reduced sleep duration.

CONCLUSIONS

Although the presented studies could not establish a direct causal relationship between BMS and sleep disturbances, it supports the evidence that sleep disturbance is associated with symptoms of BMS. Management strategies to improve sleep may be considered in future research for managing BMS patients.

What are the biopsychosocial risk factors associated with pain in postpartum runners? Development of a clinical decision tool

Background

In 2019, a majority of runners participating in running events were female and 49% were of childbearing age. Studies have reported that women are initiating or returning to running after childbirth with up to 35% reporting pain. There are no studies exploring running-related pain or risk factors for this pain after childbirth in runners. Postpartum runners have a variety of biomechanical, musculoskeletal, and physiologic impairments from which to recover from when returning to high impact sports like running, which could influence initiating or returning to running. Therefore, the purpose of this study was to identify risk factors associated with running-related pain in postpartum runners with and without pain. This study also aimed to understand the compounding effects of multiple associative risk factors by developing a clinical decision tool to identify postpartum runners at higher risk for pain.

Methods

Postpartum runners with at least one child ≤36 months who ran once a week and postpartum runners unable to run because of pain, but identified as runners, were surveyed. Running variables (mileage, time to first postpartum run), postpartum variables (delivery type, breastfeeding, incontinence, sleep, fatigue, depression), and demographic information were collected. Risk factors for running-related pain were analyzed in bivariate regression models. Variables meeting criteria (P<0.15) were entered into a multivariate logistic regression model to create a clinical decision tool. The tool identified compounding factors that increased the probability of having running-related pain after childbirth.

Results

Analyses included 538 postpartum runners; 176 (32.7%) reporting running-related pain. Eleven variables were included in the multivariate model with six retained in the clinical decision tool: runner type-novice (OR 3.51; 95% CI 1.65, 7.48), postpartum accumulated fatigue score of >19 (OR 2.48; 95% CI 1.44, 4.28), previous running injury (OR 1.95; 95% CI 1.31, 2.91), vaginal delivery (OR 1.63; 95% CI 1.06, 2.50), incontinence (OR 1.95; 95% CI 1.31, 2.84) and <6.8 hours of sleep on average per night (OR 1.89; 95% CI 1.28, 2.78). Having ≥ 4 risk factors increased the probability of having running-related pain to 61.2%.

Conclusion

The results of this study provide a deeper understanding of the risk factors for running-related pain in postpartum runners. With this information, clinicians can monitor and educate postpartum runners initiating or returning to running. Education could include details of risk factors, combinations of factors for pain and strategies to mitigate risks. Coaches can adapt running workload accounting for fatigue and sleep fluctuations to optimize recovery and performance. Future longitudinal studies that follow asymptomatic postpartum women returning to running after childbirth over time should be performed to validate these findings.

Sleep quality in relation to social support and resilience among rural empty-nest older adults in China

BACKGROUND

Population ageing is a global problem, and one of the adverse effects in China is the rural empty-nest phenomenon, which is increasingly prominent. Recently, the sleep problems of rural empty nesters have gradually aroused attention. The purpose of this article was to investigate sleep quality and its influencing factors in rural empty nesters and explore the correlation between social support, resilience and sleep quality in the target population.

METHODS

This study investigated 250 empty nesters in six rural areas. Information on sociodemographics, sleep quality, social support and resilience was collected. Univariate analysis and multivariate analysis were used to determine the influencing factors of sleep quality. The Spearman correlation coefficient was used to evaluate the linear associations between social support, resilience and sleep quality. The mediating effect of resilience between social support and sleep quality was measured by bootstrap-mediated analysis.

RESULTS

The sleep quality score among rural empty nesters was 6.74 ± 3.80. Sleep quality was influenced significantly by marital status, monthly income, number of chronic diseases and frequency of communication with children. Besides, social support and resilience were significantly positively correlated with sleep quality. Resilience was not the only mediating variable between social support and sleep quality.

CONCLUSION

The sleep quality of rural empty nesters was poorer than those of the general rural older adults and affected by multiple factors. Moreover, social support and resilience had a positive impact on the sleep quality of rural empty nesters, which provided new ideas for exploring specific measures to improve their sleep quality in the future.

The relationship between restless sleep and symptoms of the knee: data from the Osteoarthritis Initiative

OBJECTIVE

To examine the associations between restless sleep and knee symptoms among individuals with radiographically confirmed KOA.

METHODS

Cross-sectional and longitudinal associations were examined using Osteoarthritis Initiative (OAI) data. Participants with radiographic KOA (n = 2517) were asked how often sleep was restless in the past week over the 4 years, and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) was used to measure knee symptoms. Adjusted β coefficients (aβ) and 95% confidence intervals (CI) were derived from generalized estimating equations (GEEs) models stratified by sex.

RESULTS

One in 7 participants reported ≥ 3 nights with restless sleep. Cross-sectional analyses indicated that restless sleep 5-7 nights was associated with worse symptoms (Women: pain: aβ 1.93, 95% CI 1.12-2.74, stiffness: aβ 0.57, 95% CI 0.19-0.94, physical function: aβ 5.68, 95% CI 3.09-8.27; Men: pain: aβ = 1.85, 95% CI 0.85-2.86; stiffness: aβ 0.63, 95% CI 0.15-1.12; physical function: aβ 5.89, 95% CI 2.68-9.09) compared with < 1 night. Longitudinal analyses confirmed that more nights with restless sleep were associated with worse pain (P trend = 0.01) and function (P trend = 0.04) in women and physical function in men (P trend = 0.04), although estimates did not meet thresholds for minimal clinically meaningful differences.

CONCLUSION

While the analysis of cross-sectional data supported the association between restless sleep and KOA symptoms, such relationships were not confirmed in more robust longitudinal analysis. Further research examining whether sleep quality, duration, or disorders is associated with worsening symptoms in persons with KOA is warranted. Key Points • The prevalence of frequent restless sleep among persons with knee OA is not uncommon. • There were linear trends between frequency of restless sleep and self-reported symptoms of the knee in cross-sectional analyses. • In the more robust longitudinal analysis, despite the statistically significant linear trends observed between frequency of restless sleep and symptoms (women: pain and physical function; men: function), none appeared to reach the a priori selected ranges for minimally clinically relevant differences.

Positive Association of Serum Alkaline Phosphatase Level with Severe Knee Osteoarthritis: A Nationwide Population-Based Study

Serum alkaline phosphatase (ALP), a well-known marker of hepatobiliary and bone disorders, has recently been discovered to be a biochemical marker of cardiometabolic diseases and chronic low-grade inflammation. We aimed to evaluate the association of serum ALP level with knee osteoarthritis in the general population. The study included 3060 men and women aged ≥50 years who participated in the 2009–2011 Korea National Health and Nutrition Examination Survey. The participants were categorized into three groups based on log-transformed serum ALP level as follows: T1 (1.74–2.32), T2 (2.33–2.43), and T3 (2.44–3.01). Their radiographs were evaluated by two well-trained radiologists using the Kellgren–Lawrence (KL) grading system. After excluding those with KL Grade 0, we categorized the remaining participants into two groups, a severe osteoarthritis group (KL Grade 4) and a non-severe osteoarthritis group (KL Grades 1 to 3). The odds ratios (ORs) with 95% confidence intervals (CIs) of severe osteoarthritis according to the tertiles of log-transformed serum ALP levels of patients with osteoarthritis were calculated using a weighted multivariate logistic regression analysis. Compared with T1, the adjusted ORs (95% CIs) for severe osteoarthritis of the T3 serum ALP group was 1.613 (1.087–2.394; p = 0.018) after adjusting for the confounding variables. Conclusively, serum ALP activity was independently and positively associated with severe knee osteoarthritis in middle-aged and older adults.

Sleep Disturbance and Its Association with Pain Severity and Multisite Pain: A Prospective 10.7-Year Study

INTRODUCTION

Sleep disturbance is often comorbid with chronic pain disorders, with emerging evidence suggesting a stronger effect of sleep disturbance on pain than vice versa; however, few studies have evaluated the long-term associations between sleep disturbance and pain. This study was to examine the associations of sleep disturbance with knee pain severity, number of painful sites (NPS) and persistent pain in a 10.7-year cohort study.

METHODS

A total of 1099 community-dwelling older adults (age mean ± SD, 63 ± 7.5 years; 51% female) were recruited and followed up at 2.6, 5.1 and 10.7 years later. Data on demographics, body mass index, physical activity and comorbidities were collected. At each time point, sleep disturbance, knee pain severity and NPS were assessed by using questionnaires. Multisite pain (MSP) was defined as NPS ≥ 2. Persistent knee pain or MSP was defined as having knee pain or MSP at all time points, respectively. Multivariable mixed-effects models and log-binomial regression were applied.

RESULTS

In multivariable analyses, sleep disturbance was associated with greater knee pain severity (β 0.91/unit, 95% CI 0.70-1.11) and more NPS [(relative risk (RR) 1.10/unit, 95% CI 1.07-1.14] in a dose-response manner. Persistent sleep disturbance was associated with persistent knee pain (RR 1.90, 1.26-2.87) and MSP (RR 1.29, 1.07-1.56). Persistent knee pain and MSP were also associated with persistent sleep disturbance (knee pain: RR = 1.99; MSP: RR = 2.71, both P < 0.05).

CONCLUSIONS

Sleep disturbance was independently associated with greater pain severity and NPS in a dose-response manner. A reciprocal relationship between persistent sleep disturbance and persistent pain suggests treating either problem could help the other.