Dietary intake mediates the relationship of body fat to pain

The effect of a low-carbohydrate diet on evoked pain and quality of life in Non-Hispanic black women with knee osteoarthritis: a pilot study

BACKGROUND

Knee osteoarthritis (KOA) is a prevalent chronic pain condition that can significantly impact quality of life and contribute to recognized chronic pain racial disparities. We have shown that a low-carbohydrate diet (LCD) can reduce KOA-related pain. Our previous work suggested that the LCD was more beneficial for women and non-Hispanic Black (NHB) adults, but our sample was not sufficiently diverse. Thus, we sought to determine whether the LCD may be beneficial for NHB women with KOA on measures of self-reported and evoked pain.

METHODS

Fourteen NHB women (M = 55.93, S.D. = 7.79 years of age) with KOA were recruited to participate in a pilot 6-week LCD intervention. Measures of pain sensitivity, disability, physical functioning, overall chronic pain, quality of life, and dietary habits were taken at baseline and at 3- and 6-weeks of the LCD intervention.

RESULTS

Overall, participants showed significant differences in self-reported measures of daily pain, pain interference, stiffness, physical functioning, depressive symptoms, food knowledge and food security. Participants also showed reduced evoked pain in the timed walk and chair stand tasks.

CONCLUSION

A 6-week LCD provided a range of benefits related to pain and quality of life in NHB women with KOA. The utilization of a LCD is a modifiable, non-pharmacological and accessible alternative for chronic KOA that may reduce pain disparities and improve quality of life.

TRIAL REGISTRATION

This article reports the original results of a dietary healthcare intervention registered at clinicaltrials.gov (NCT04343716, registered on 13/04/2020).

Better diet quality is associated with reduced body pain in adults regardless of adiposity: Findings from the Whyalla Intergenerational Study of Health

Dietary intake has been associated with pain and physical function, but it is unclear if these relationships are mediated by adiposity. Data were derived from the Whyalla Intergenerational Study of Health (n = 654, 57% women). Structural equation modelling tested the hypotheses that adiposity (body mass index (BMI), waist circumference (WC), or body fat (BF, dual energy x-ray absorptiometry)) would mediate the relationship between diet quality (Dietary Guideline Index (DGI) total, core, or non-core scores) and pain (Short Form-36 bodily pain scale (SF36-BPS)), or physical function (grip-strength), overall, and by gender. Adiposity did not mediate a relationship between DGI scores and pain. Direct effects were observed between DGI total scores and SF36-BPS accounting for BMI (β = 0.170, 95% CI 0.002, 0.339), and between DGI core food scores and SF36-BPS (BMI, β = 0.278, 95% CI 0.070, 0.486; WC, β = 0.266, 95% CI 0.058, 0.474; BF, β = 0.266, 95% CI 0.060, 0.473). In women, direct effects existed between DGI scores and SF36-BPS (DGI total scores, BMI, β = 0.388, 95% CI 0.162, 0.613; WC, β = 0.372, 95% CI 0.146, 0.598; BF, β = 0.382, 95% CI 0.158, 0.605, and DGI core scores, BMI, β = 0.482, 95% CI 0.208, 0.757; WC, β = 0.472, 95% CI 0.197, 0.747; BF, β = 0.467, 95% CI 0.195, 0.739), and DGI total scores and grip-strength (BMI, β = 0.075, 95% CI 0.008, 0.142; WC, β = 0.076, 95% CI 0.009, 0.143; BF, β = 0.079, 95% CI 0.011, 0.146). Better diet quality is associated with lower bodily pain, irrespective of adiposity. Findings highlight the potential role of diet quality in pain management and function, particularly in women.

Healthy dietary indices and noncancer pain: a systematic review of cross-sectional and longitudinal studies

ABSTRACT

Pain is a global public health problem given its high prevalence and incidence, long duration, and social and economic impact. There is growing interest in nutrition as potential modifiable risk factor related to pain; however, the associations between healthy dietary patterns and pain have not yet been well established. Thus, we aimed to systematically review and synthesise current cross-sectional and longitudinal evidence on the relationship between a priori healthy dietary patterns and noncancer pain among adults aged ≥18 years. We identified relevant published cross-sectional and longitudinal studies by systematically searching several electronic databases from inception to September 2021. Risk of bias was assessed using the modified Newcastle-Ottawa scale for cohort studies. A total of 14 cross-sectional and 6 longitudinal studies were included in the review. These studies measured different dietary scores/indices, such as different measures of adherence to the Mediterranean diet and the dietary inflammatory index. Pain ascertainment methods and pain measurements used differed across studies. All 20 of the included studies had different study designs and statistical analysis. Of these studies, 10 reported an inverse association between adherence to a healthy dietary pattern and pain, 5 reported mixed results, and 5 reported no associations. Despite notable heterogeneity, 50% of included observational studies reported that adherence to a healthy diet, particularly the Mediterranean diet, is inversely associated with pain. Of note, the cross-sectional design of most studies precludes any causal interpretation. Moreover, limited and inconsistent evidence from longitudinal studies highlights the need for further studies.

Enhanced pain sensitivity in obese patients with obstructive sleep apnoea syndrome is partially reverted by treatment: An exploratory study

BACKGROUND

Obesity is frequently associated with obstructive sleep apnoea syndrome (OSA) and chronic pain. OSA as well as continuous positive airway pressure (CPAP) treatment may modulate the pain perception threshold (PT) in patients with obesity.

METHODS

In this prospective, longitudinal study, all patients admitted for obesity assessment were screened for OSA by nocturnal polygraphy (SOMNOcheck^® , IAH ≥10) and performed mechanical (Von Frey electronic device) and electrical (PainMatcher^® ) pain tests. Those with severe OSA were retested for PT 1 month after initiation of CPAP therapy. Newly diagnosed patients with severe OSA (hypopnea apnoea index >30) have been offered to start CPAP treatment.

RESULTS

Among 85 patients, there were 27 OSA patients, aged between 40 ± 13.2 years with a BMI of 42 ± 7.2 kg/m² . Severe OSA patients (N = 11) showed a lower PT than non-OSA patients (N = 58) during mechanical (177 ± 120 vs. 328 ± 136 g, p < 0.01) and electrical methods (7.4 ± 6.4 vs. 12.9 ± 6.7 stimulation duration steps; p = 0.03). In the severe OSA group (N = 7), an increased PT was observed 1 month after CPAP treatment during mechanical pain testing (298 ± 69 vs. 259 ± 68 g, p < 0.05), but not during electrical pain testing (11.5 ± 3.0 vs. 12.4 ± 3.8 stimulation duration steps, p = 0.50).

CONCLUSION

In patients with obesity, this exploratory study showed that the presence of an OSA is associated with a decreased PT, whereas implantation of a CPAP device tends to normalize pain perception.

Fibromyalgia in women: association of inflammatory plasma proteins, muscle blood flow, and metabolism with body mass index and pain characteristics

Supplemental Digital Content is Available in the Text.

Metabolism and inflammation interact in fibromyalgia with obesity that can lead to chronic low-grade inflammation.

Introduction:

Obesity is a common comorbidity in fibromyalgia (FM). Both FM and obesity have been connected to low-grade inflammation, although it is possible that previously reported inflammatory alterations in FM primarily may be linked to increased body mass index (BMI).

Objective:

This study aimed to investigate whether the inflammatory plasma protein profile, muscle blood flow, and metabolism and pain characteristics (clinical parameters and patient-reported outcome measurements) differed between female patients with FM with and without obesity.

Methods:

Patients with FM underwent clinical examinations, physical tests, and answered questionnaires. They were dichotomized according to BMI (<30 kg/m² [n = 14]; ≥30 kg/m² [n = 13]). Blood samples were collected and analyzed using a panel of 71 inflammatory plasma proteins.

Results:

There were significant (P < 0.05) differences in blood pressure, pulse, max VO2, pain intensity, physical capacity, and Fibromyalgia Impact Questionnaire between the groups; the obese group had higher blood pressure, pulse, pain intensity, and Fibromyalgia Impact Questionnaire. There were 14 proteins that contributed to the group belonging. The 4 most important proteins for the group discrimination were MIP1β, MCP4, IL1RA, and IL6, which showed higher concentrations in obese patients with FM. Significantly decreased blood flow and increased concentration of pyruvate were detected in obese patients compared with nonobese patients. There was significant correlation between inflammatory proteins and sedentary behavior and health status in obese patients with FM.

Conclusions:

These findings suggest that metabolism and inflammation interact in female patients with FM with obesity and might cause chronic low-grade inflammation. Screening for obesity and monitoring of BMI changes should be considered in the treatment of patients with FM.

Diet/Nutrition: Ready to Transition from a Cancer Recurrence/Prevention Strategy to a Chronic Pain Management Modality for Cancer Survivors?

Evidence for the relationship between chronic pain and nutrition is mounting, and chronic pain following cancer is gaining recognition as a significant area for improving health care in the cancer survivorship population. This review explains why nutrition should be considered to be an important component in chronic pain management in cancer survivors by exploring relevant evidence from the literature and how to translate this knowledge into clinical practice. This review was built on relevant evidence from both human and pre-clinical studies identified in PubMed, Web of Science and Embase databases. Given the relationship between chronic pain, inflammation, and metabolism found in the literature, it is advised to look for a strategic dietary intervention in cancer survivors. Dietary interventions may result in weight loss, a healthy body weight, good diet quality, systemic inflammation, and immune system regulations, and a healthy gut microbiota environment, all of which may alter the pain-related pathways and mechanisms. In addition to being a cancer recurrence or prevention strategy, nutrition may become a chronic pain management modality for cancer survivors. Although additional research is needed before implementing nutrition as an evidence-based management modality for chronic pain in cancer survivors, it is already critical to counsel and inform this patient population about the importance of a healthy diet based on the data available so far.

Poor diet quality is associated with self-reported knee pain in community-dwelling women aged 50 years and older

In the current study, we aimed to examine the association between knee pain and diet quality in women aged ≥ 50 years using data from the Korea National Health and Nutrition Examination Survey. This was a population-based, cross-sectional study. Diet quality was assessed using the Diet Quality Index-International (DQI-I), and knee pain and osteoarthritis were self-reported. A multivariate logistic regression model was used to adjust for age, body mass index, household income, marital status, education, occupation, smoking status, hazardous alcohol use, regular physical activity, menopause, and chronic diseases, including hypertension, diabetes, dyslipidemia, osteoarthritis, and depression. A total of 3,881 women were included in this study, and the prevalence of knee pain was 25.4%. The intakes of total energy, protein, and fat were lower in women with knee pain than in those without (all P < 0.01), while the carbohydrate intake was higher (P = 0.01). No significant differences were noted in the scores for variety, overall balance, and moderation components, except for the item of total fat intake, between the DQI-I scores for women with and without knee pain, after adjusting for age. Women without knee pain showed higher scores in several items of the adequacy component (P < 0.05) than did women with knee pain. The total DQI-I scores were lower in women with knee pain than in women without knee pain, after adjusting for covariates, including osteoarthritis (OR = 0.985, 95% CI = 0.973–0.997, P = 0.01). Knee pain independent of osteoarthritis was associated with poor diet quality in community-dwelling women aged ≥ 50 years.

Dietary Interventions Are Beneficial for Patients with Chronic Pain: A Systematic Review with Meta-Analysis

Background

The standard Western diet is high in processed hyperpalatable foods that displace nutrient-dense whole foods, leading to inflammation and oxidative stress. There is limited research on how these adverse metabolic drivers may be associated with maladaptive neuroplasticity seen in chronic pain and whether this could be attenuated by a targeted nutritional approach. The aim of this study was to review the evidence for whole-food dietary interventions in chronic pain management.

Method

A structured search of eight databases was performed up to December 2019. Two independent reviewers screened studies and evaluated risk of bias by using the National Institutes of Health assessment tool for controlled or pre–post studies and the Joanna Briggs checklist for case reports. A meta-analysis was performed in Review Manager.

Results

Forty-three studies reporting on 48 chronic pain groups receiving a whole-food dietary intervention were identified. These included elimination protocols (n = 11), vegetarian/vegan diets (n = 11), single-food changes (n = 11), calorie/macronutrient restriction (n = 8), an omega-3 focus (n = 5), and Mediterranean diets (n = 2). A visual analog scale was the most commonly reported pain outcome measure, with 17 groups reporting a clinically objective improvement (a two-point or 33% reduction on the visual analog scale). Twenty-seven studies reported significant improvement on secondary metabolic measures. Twenty-five groups were included in a meta-analysis that showed a significant finding for the effect of diet on pain reduction when grouped by diet type or chronic pain type.

Conclusion

There is an overall positive effect of whole-food diets on pain, with no single diet standing out in effectiveness. This suggests that commonalities among approaches (e.g., diet quality, nutrient density, weight loss) may all be involved in modulating pain physiology. Further research linking how diet can modulate physiology related to pain (such as inflammation, oxidative stress, and nervous system excitability) is required.

The sad weekend: A perilous North American tradition

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Long-term consumption of poor-quality diet prolonged recovery.

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Mice with only weekend access to poor-quality diet recovered similarly to those with constant access.

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Diet composition significantly changed abundance and diversity of bacterial groups in the gut.

Obesity is a global concern and affects millions of Americans who consume poor-quality diets. Diets directly affect the gut microbiota, which can have subsequent effects on inflammation and contribute to other chronic states. Previously we have shown that a Standard American Diet (SAD) increased immune cell activation and prolonged recovery and that a beneficial diet could reduce these negative effects. Here, male and female mice were given access to regular chow (REG), SAD, our Anti-Inflammatory Diet (AID) or a combination of SAD and AID. This latter group was modeled on the commonplace dietary pattern of healthy eating during the week (AID: Monday-Friday) and relaxed eating patterns on the weekend (SAD: Saturday-Sunday). After 14 weeks of diet consumption and an inflammatory injury, we found that the SAD prolonged and the AID promoted recovery. However, recovery was significantly delayed in those mice consuming the AID-SAD, regardless of weekly healthy diet access. In addition, fecal samples taken during the study revealed dramatic differences in microbial community composition, relative abundance of abundant bacterial phyla and alpha diversity. These data confirm the impact of diet on gut microbiota and suggest a relation between abundance of specific bacterial taxa and susceptibility to prolonged recovery from injury.

Dietary Interventions for Treatment of Chronic Pain: Oxidative Stress and Inflammation

Chronic pain is highly prevalent in the United States, impacting 28.4% of the adult population, or 69.6 million people, as of 2016. Chronic pain is often associated with anxiety, depression, and restrictions in mobility and daily activities, substantially reducing quality of life. Analgesics, especially opioids, are one of the primary pharmaceutical treatment methods for chronic pain. However, prescription opioid misuse and abuse has become increasingly prevalent and concerning, prompting the need for research into alternative treatment methods which avoid the side effects of traditional treatments. Chronic pain is, in part, thought to be the result of oxidative stress and inflammation, and clinical research has indicated links between these conditions and diet. Thus, dietary interventions are a particularly promising therapeutic treatment for chronic pain, with numerous studies suggesting that diet has a noticeable effect on pain as far down as the cellular level. In this review article, data from a number of clinical trials assessing the effect of three diets—antioxidant-rich, low-carbohydrate, and Mediterranean—on oxidative stress and inflammation is compiled and discussed in the context of chronic pain. Clinical data suggests that low-carbohydrate diets and Mediterranean diets both are especially promising dietary interventions.

Participants with chronic pain do not perceive diet as a contributing factor to their pain: a survey-based study

Aim: To explore the reported diet of Australians with chronic pain and their perceived role of food within their pain experience. Methods: A cross-sectional study of 50 participants reporting chronic pain was undertaken using pain and nutritional questionnaires as well as anthropometric measures. Results: Participants rated their diet between 'good' and 'excellent' (76%) and one that promoted well-being (62%), however 74% were overweight or obese (average BMI 30) with multiple co-morbidities. There was no correlation between measures of dietary adherence and knowledge with reported pain. Conclusion: Participants generally reported their diets to be good, however, this was not reflected in their habitual diet. There was a low perceived role of food altering pain perception.

Obesity and pain: a systematic review

BACKGROUND/OBJECTIVES

The current systematic review considered research published within the 10 years preceding June 2019, dealing with the topic of obesity and pain. Within the context of the complex biological and behavioral interrelationships among these phenomena, we sought to identify gaps in the literature and to highlight key targets for future transdisciplinary research. The overarching inclusion criteria were that the included studies could directly contribute to our understanding of these complex phenomena.

METHODS

We searched PubMed/Medline/Cochrane databases dating back 10 years, using the primary search terms "obesity" and "pain," and for a secondary search we used the search terms "pain" and "diet quality."

RESULTS

Included studies (n = 70) are primarily human; however, some animal studies were included to enhance understanding of related basic biological phenomena and/or where human data were absent or significantly limited.

CONCLUSIONS

Our overall conclusions highlight (1) the mechanisms of obesity-related pain (i.e., mechanical, behavioral, and physiological) and potential biological and behavioral contributors (e.g., gender, distribution of body fat, and dietary factors), (2) the requirement for accurate and reliable objective measurement, (3) the need to integrate biological and behavioral contributors into comprehensive, well-controlled prospective study designs.

The pain of weight-related stigma among women with overweight or obesity

Pain is prevalent among individuals with overweight or obesity but few studies have examined the mechanism linking pain with excess body weight. Because there is evidence that social and physical pain may be processed through similar physiological mechanisms, weight-stigma may potentiate the experience of physical pain through shared neuroanatomical pathways. This study evaluated the relationship between perceived weight stigma and self-reported bodily pain in a sample of overweight and obese adult women. Sixty-one women with a body mass index (BMI) between 25-35 completed self-report questionnaires assessing perceived stigma, internalized weight stigma, and self-reported pain. Height and weight were measured and participants completed a demographic and health history questionnaire. Hierarchical regression analyses were utilized to predict self-reported pain from perceived stigma, adjusting for demographic variables associated with self-reported pain as well as pain-related conditions. Perceived stigma was associated with pain F(6, 54)=6.10, p<.001) as was internalized stigma. Perceived stigma mediated the relationship between BMI and bodily pain among individuals with a BMI in the overweight range but not among individuals with a BMI in the obese range. Weight-related stigma among women with overweight or obesity appears to be associated with greater experience of physical pain. These results underscore the need to evaluate multiple mechanisms that might explain the relationship between bodily pain and body weight and to determine how the relationship may vary across different subgroups of individuals.

Is excess weight a burden for older adults who suffer chronic pain?

Background

Obesity and chronic pain are common comorbidities and adversely influence each other. Advanced age is associated with more comorbidities and multi-morbidities. In this study, we investigated the burden of overweight/obesity and its comorbidities and their associations with chronic pain in a random population sample of Swedish older adults.

Methods

The cross-sectional analysis involved a random sample of a population ≥ 65 years in south-eastern Sweden (N = 6243). Data were collected from a postal questionnaire that addressed pain aspects, body mass index (BMI), and health experiences. Chronic pain was defined as pain during the previous three months. According to the 0–10 Numeric Rating Scale, pain scored ≥7 corresponds to severe pain. Binary logistic regression was used to determine the variables associated to pain aspects.

Results

A total of 2633 (42%) reported chronic pain. More obese older adults (BMI ≥30 kg/m²) experienced chronic pain (58%) than those who were low-normal weight (BMI < 25 kg/m², 39%) or overweight (25 ≤ BMI < 30 kg/m², 41%). Obese elderly more frequently had pain in extremities and lower back than their peers. In the multivariate model, obesity (Odds Ratio (OR) 1.59, 95% Confidence Interval (CI) 1.33–1.91) but not overweight (OR 1.08, 95% CI 0.95–1.22) was associated with chronic pain. Obesity (OR 1.53, 95% CI 1.16–2.01) was also significantly related to severe pain. We also found other comorbidities – i.e., traumatic history (OR 2.52, 95% CI 1.99–3.19), rheumatic diseases (OR 5.21, 95% CI 4.54–5.97), age ≥ 85 years (OR 1.66, 95% CI 1.22–2.25), and depression or anxiety diagnosis (OR 1.83, 95% CI 1.32–2.53) – showed stronger associations with pain aspects than weight status. Conclusion: In older adults, excess weight (BMI 30 or above) is a potentially modifiable factor but not the only risk factor that is associated with chronic pain and severe pain. Future studies should investigate the effectiveness of interventions that treat comorbid pain and obesity in older adults.

Food pyramid for subjects with chronic pain: foods and dietary constituents as anti-inflammatory and antioxidant agents

Emerging literature suggests that diet constituents may play a modulatory role in chronic pain (CP) through management of inflammation/oxidative stress, resulting in attenuation of pain. We performed a narrative review to evaluate the existing evidence regarding the optimum diet for the management of CP, and we built a food pyramid on this topic. The present review also describes the activities of various natural compounds contained in foods (i.e. phenolic compounds in extra-virgin olive oil (EVO)) listed on our pyramid, which have comparable effects to drug management therapy. This review included 172 eligible studies. The pyramid shows that carbohydrates with low glycaemic index should be consumed every day (three portions), together with fruits and vegetables (five portions), yogurt (125 ml), red wine (125 ml) and EVO; weekly: legumes and fish (four portions); white meat, eggs and fresh cheese (two portions); red or processed meats (once per week); sweets can be consumed occasionally. The food amounts are estimates based on nutritional and practical considerations. At the top of the pyramid there is a pennant: it means that CP subjects may need a specific customised supplementation (vitamin B12, vitamin D, n-3 fatty acids, fibre). The food pyramid proposal will serve to guide dietary intake with to the intent of alleviating pain in CP patients. Moreover, a targeted diet can also help to solve problems related to the drugs used to combat CP, i.e. constipation. However, this paper would be an early hypothetical proposal due to the limitations of the studies.

Recalled early life adversity and pain: the role of mood, sleep, optimism, and control

Early life adversity (ELA) has been associated with pain symptomatology in adulthood, but mechanisms and moderators of these associations are unclear. Using recall based and concurrently assessed self-report data, we examined associations between ELA, mood, sleep, and recent pain intensity and interference, and whether optimism and perceived control weakened these associations in a midlife community sample of diverse adults reporting some ELA. Controlling for demographic variables and BMI, higher levels of ELA were associated with more pain intensity and interference; greater sleep disturbance and negative mood accounted for these associations. When moderation was examined, only the path from sleep disturbance to pain interference was significantly attenuated for those with higher optimism and higher perceived control. These findings suggest that higher levels of ELA may link with pain in adulthood through poorer mood and sleep, and that resilience resources such as optimism and control may buffer some of these pathways.