Pain and modifiable risk factors among weight loss seeking Veterans with overweight

Activation of α7 nicotinic receptors attenuated hyperalgesia and anxiety induced by palatable obesogenic diet withdrawal

Consumption of palatable food (PF) can alleviate anxiety, and pain in humans. Contrary, spontaneous withdrawal of long-term PF intake produces anxiogenic-like behavior and abnormal pain sensation, causing challenges to weight-loss diet and anti-obesity agents. Thus, we examined α7-nicotinic acetylcholine receptors (α7nAChR) involvement since it plays essential role in nociception and psychological behaviors.

METHODS

Adult male C57BL/6 mice were placed on a Standard Chow (SC) alone or with PF on intermittent or continuous regimen for 6 weeks. Then, mice were replaced with normal SC (spontaneous withdrawal). Body weight, food intake, and calories intake with and without the obesogenic diet were measured throughout the study. During PF withdrawal, anxiety-like behaviors and pain sensitivity were measured with PNU-282987 (α7nAChR agonist) administration.

RESULTS

Six weeks of SC + PF-intermittent and continuous paradigms produced a significant weight gain. PF withdrawal displayed hyperalgesia and anxiety-like behaviors. During withdrawal, PNU-282987 significantly attenuated hyperalgesia and anxiety-like behaviors.

CONCLUSION

The present study shows that a PF can increase food intake and body weight. Also, enhanced pain sensitivity and anxiety-like behavior were observed during PF withdrawal. α7nAChR activation attenuated anxiolytic-like behavior and hyperalgesia in PF abstinent mice. These data suggest potential therapeutic effects of targeting α7 nAChRs for obesity-withdrawal symptoms in obese subjects.

Eating disorders and disordered eating in servicemen and women: A narrative review

OBJECTIVE

Eating disorders (EDs) are mental illnesses impacting all aspects of an individual's life. Recent research has examined EDs and disordered-eating behaviors in the military, a population subject to body composition standards, fitness requirements, and extreme stress. The purpose of this narrative review was to investigate ED and disordered-eating prevalence and their risk factors in ROTC (reserve officers' training corps), active-duty, and veteran servicemembers. The secondary purpose was to provide policy recommendations to reduce the burden of these conditions in the military.

METHODS

PubMed and PsycINFO were reviewed for relevant articles. All studies including data on EDs or disordered eating in U.S. active-duty, ROTC, or veteran populations were considered.

RESULTS

Results revealed a high burden of EDs and disordered eating with bulimic- and binge-type behaviors being the most common. Servicemembers exposed to trauma, including military sexual assault, and those with comorbidities like PTSD showed a higher prevalence. Body composition and fitness testing were also associated with a higher risk. Qualitative studies suggest these conditions serve as coping mechanisms for aspects of military life.

CONCLUSIONS

The high prevalence of EDs and disordered eating in the military points toward the importance of identification, treatment, and prevention. Policy change is necessary to protect servicemembers.

Racial and weight discrimination associations with pain intensity and pain interference in an ethnically diverse sample of adults with obesity: a baseline analysis of the clustered randomized-controlled clinical trial the goals for eating and moving (GEM) study

BACKGROUND

Everyday experiences with racial (RD) and weight discrimination (WD) are risk factors for chronic pain in ethnically diverse adults with obesity. However, the individual or combined effects of RD and WD on pain in adults with obesity is not well understood. There are gender differences and sexual dimorphisms in nociception and pain, but the effect of gender on relationships between RD, WD, and pain outcomes in ethnically diverse adults with obesity is unclear. Thus, the purposes of this study were to: 1) examine whether RD and WD are associated with pain intensity and interference, and 2) explore gender as a moderator of the associations between RD, WD, and pain.

METHODS

This is a baseline data analysis from a randomized, controlled clinical trial of a lifestyle weight-management intervention. Eligible participants were English or Spanish-speaking (ages 18-69 years) and had either a body mass index of ≥30 kg/m2 or ≥ 25 kg/m2 with weight-related comorbidity. RD and WD were measured using questions derived from the Experiences of Discrimination questionnaire (EOD). Pain interference and intensity were measured using the PROMIS 29 adult profile V2.1. Linear regression models were performed to determine the associations between WD, RD, gender, and pain outcomes.

RESULTS

Participants (n = 483) reported mild pain interference (T-score: 52.65 ± 10.29) and moderate pain intensity (4.23 ± 3.15). RD was more strongly associated with pain interference in women (b = .47, SE = .08, p < 001), compared to men (b = .14, SE = .07, p = .06). Also, there were no significant interaction effects between RD and gender on pain intensity, or between WD and gender on pain interference or pain intensity.

CONCLUSIONS

Pain is highly prevalent in adults with obesity, and is impacted by the frequencies of experiences with RD and WD. Further, discrimination against adults with obesity and chronic pain could exacerbate existing racial disparities in pain and weight management. Asking ethnically diverse adults with obesity about their pain and their experiences of RD and WD could help clinicians make culturally informed assessment and intervention decisions that address barriers to pain relief and weight loss.

TRIAL REGISTRATION

NCT03006328.

Chronic pain and depressive symptoms are related to food insecurity among urban food bank users

BACKGROUND

Food bank users suffer high food insecurity. Food insecurity increases risk for chronic health conditions. However, chronic pain and its relation to food insecurity among food bank users is unknown. Knowledge about populations with chronic pain is important to direct appropriate public health nutritional strategies.

METHODS

Participants completed a survey including sleep, pain, depressive symptoms and food insecurity measures. Descriptive statistics characterized the burden of chronic pain among the sample, and a series of chi-square and t-tests assessed for demographic differences between food bank users who reported pain compared to those who did not. Logistic regression tested for variables predicting food insecurity.

RESULTS

Within the sample (N = 207), 53% reported a chronic pain diagnosis. Adults with pain were more likely to receive food stamps and to have a mental health condition than those without pain. Regression analyses revealed that depressive symptoms and chronic pain significantly predicted food insecurity when controlling for age and gender.

CONCLUSIONS

Exploring the link between depression, pain and nutritional resources may enhance understanding of causal relationships driving food insecurity. Public health officials should address nutritional needs of adults including those with chronic pain who use food bank services.

Modulation of Pain Sensitivity by Chronic Consumption of Highly Palatable Food Followed by Abstinence: Emerging Role of Fatty Acid Amide Hydrolase

There is a strong relationship between palatable diet and pain sensitivity, and the cannabinoid and opioid systems might play an important role in this correlation. The palatable diet used in many animal models of obesity is the cafeteria (CAF) diet, based on human food with high sugar, salt, and fat content. In this study, we investigated whether long-term exposure to a CAF diet could modify pain sensitivity and explored the role of the cannabinergic system in this modification. Male Sprague–Dawley rats were divided into two groups: one fed with standard chow only (CO) and the other with extended access (EA) to a CAF diet. Hot plate and tail flick tests were used to evaluate pain sensitivity. At the end of a 40-day CAF exposure, EA rats showed a significant increase in the pain threshold compared to CO rats, finding probably due to up-regulation of CB1 and mu-opioid receptors. Instead, during abstinence from palatable foods, EA animals showed a significant increase in pain sensibility, which was ameliorated by repeated treatment with a fatty acid amide hydrolase inhibitor, PF-3845 (10 mg/kg, intraperitoneally), every other day for 28 days. Ex vivo analysis of the brains of these rats clearly showed that this effect was mediated by mu-opioid receptors, which were up-regulated following repeated treatment of PF-3845. Our data add to the knowledge about changes in pain perception in obese subjects, revealing a key role of CB1 and mu-opioid receptors and their possible pharmacological crosstalk and reinforcing the need to consider this modulation in planning effective pain management for obese patients.

Increased Pain Sensitivity in Obese Patients After Lung Cancer Surgery

Background: Obesity and cancer are recognized worldwide health threats. While there is no reported causal relationship, the increasing frequency of both conditions results in a higher incidence of obese patients who are being treated for cancer. Physiological data indicate that there is a relationship between obesity and susceptibility to pain; however, currently, there are no specific pharmacological interventions.

Objective: To evaluate the self-reported intensity of postoperative pain in obese and nonobese lung cancer who receive either thoracotomy or video-assisted thoracic surgery (VATS) surgical therapy.

Material and Methods: In 50 obese [mean body mass index (BMI) of 34.1 ± 3.2 kg/m²] and 62 nonobese (mean BMI of 24.9 ± 3 kg/m²) lung cancer patients, the intensity of pain was estimated every 4 h using a visual analog scale (VAS, 0 indicating no pain and 10 indicating “worst imaginable pain”) beginning shortly after surgery (Day O) and continuing until the day of discharge (Day D).

Results: The self-reported pain was more severe in obese than in nonobese patients, both at the time of the operation [Day O (4.5 ± 1.2 vs 3.4 ± 1.1; p < 0.0001)] and at the day of discharge [Day D (3.9 ± 1.4 vs 2.6 ± 0.9, p < 0.0001)]. This finding was consistent both in the patients after thoracotomy and after video-assisted thoracic surgery (VATS, p < 0.0001). The patients with severe pain shortly after surgery (VAS score >4) had significantly higher BMI (31.8 ± 5.6 kg/m²vs 28.8 ± 5.2 kg/m², p < 0.01) and were hospitalized longer than the remaining patients (13.0 ± 13.6 days vs 9.5 ± 3.6 days, p < 0.05).

Conclusion: The reported perception of pain in obese lung cancer patients is greater than in nonobese patients undergoing the same thoracic surgery. In obese patients, severe pain persisted longer. Pain management is an important consideration in the postoperative care of lung cancer patients, even more so with obese patients.

'Dis-comfort eating': An investigation into the use of food as a coping strategy for the management of chronic pain

OBJECTIVES

Chronic pain and obesity are major public health concerns. Animal and human models have demonstrated that eating high-sugar nutrient-dense foods confers analgesic effects. Moreover, recent research suggests that people with chronic pain may "comfort eat" to cope with their pain. Given the harmful impact of obesity on chronic pain, it is critical to determine whether pain elicits comfort eating amongst individuals with chronic pain to ensure that this potentially maladaptive pain coping strategy is not overlooked in chronic pain treatment. Therefore, this study aimed to: determine whether chronic pain intensity predicts pain-induced comfort eating and identify mediators of this relationship; to determine whether pain-induced comfort eating predicts elevated BMI; and to establish whether BMI predicts chronic pain interference.

METHODS

This study utilised a cross-sectional online survey design and a sample of 151 adults with chronic pain.

RESULTS

Over three-quarters of this chronic pain sample reported engaging in pain-induced comfort eating. Chronic pain intensity did not significantly predict pain-induced comfort eating. However, there was a significant indirect effect of chronic pain intensity on pain-induced comfort eating through stress-but not experiential avoidance or pain catastrophising. As predicted, pain-induced comfort eating significantly predicted increased BMI, and BMI in turn significantly predicted greater chronic pain interference.

DISCUSSION

This study indicates that pain-induced comfort eating is both common and harmful amongst individuals with chronic pain, across the entire BMI spectrum. Pain-induced comfort eating and stress have emerged as promising chronic pain treatment targets. The findings are discussed and interpreted in light of extant research and theory, as well as limitations of the current study. Future research directions and clinical implications are also considered.

Characterizing emotional overeating among patients with and without binge-eating disorder in primary care

OBJECTIVE

Emotional overeating and loss-of-control eating are associated with poorer weight-related and psychiatric outcomes, yet our understanding of the relationship between these variables is limited, particularly among individuals in primary care. This study examined the frequency of emotional overeating and relationship with loss-of-control eating among patients with and without binge-eating disorder (BED) seeking weight loss treatment in primary care.

METHOD

Participants were 131 adults (n = 105 female) with overweight/obesity seeking weight loss treatment in primary care. Participants completed the Eating Disorder Examination (semi-structured interview) and Yale Emotional Overeating Scale, which measures emotional overeating episodes. Height and weight were measured. Mean age and BMI were 47.60 years and 35.31 kg/m², respectively. BED criteria were met by n = 35 (26.7%) participants.

RESULTS

Participants with BED endorsed more frequent emotional overeating episodes compared to those without BED. While total emotional overeating scores were not associated with loss-of-control eating, discrete types of emotional overeating episodes (e.g., loneliness) were associated with loss-of-control eating. Emotional overeating was most often reported in response to loneliness, boredom, or anxiety, which varied by BED status.

CONCLUSIONS

Most participants endorsed recent episodes of emotional overeating; those with BED endorsed more frequent episodes. Future research examining the impact of emotional overeating on weight loss treatment outcomes is warranted.