Appraisal of current and experimental approaches to the treatment of cachexia

Risk factors for progressive sarcopenia 6 months after complete resection of lung cancer: what can thoracic surgeons do against sarcopenia?

Background

Our previous report described how postoperative progression of sarcopenia predicted long-term prognosis after complete resection of non-small cell lung cancer (NSCLC) in heavy smokers. However, there are currently no effective means to treat progressive sarcopenia. In this study, we aimed to confirm our previous findings in a larger population and to identify factors associated with postoperative progression of sarcopenia to propose possible preventative measures.

Methods

This retrospective study analyzed the data of 1,095 patients who underwent curative lobar resection for NSCLC at Kanagawa Cancer Center. We divided patients into four groups according to sex and Brinkman index (BI) above or below 600. Six-month postoperative changes in the skeletal muscle index (SMI) were calculated and associations between clinicopathological factors including changes in SMI and mortality from postoperative 6 months were examined. Only in groups in which postoperative depletion of SMI was shown to be associated with the prognosis, we identified clinicopathological factors associated with depletive SMI.

Results

The overall survival rates of 1,095 patients were 89.8% and 82.5% at 3 and 5 years, respectively. The median 6-month change in SMI was –3.4% (range, −22.3% to +17.9%). Multivariate analysis revealed that poor prognosis was independently predicted by a large reduction in the SMI (cut-off value: −10%) in males with a BI ≥600. In 391 heavy-smoking males, factors associated with a postoperative change in SMI ≤−10% were history of other cancers (including gastric cancer) low forced expiratory volume in one second (FEV 1.0, cut-off value: 1,870 mL), and prolonged operation time (cut-off value: 200 minutes).

Conclusions

Perioperative measures to prevent postoperative sarcopenia are appropriate for heavy smokers. We obtained some clues regarding countermeasures, one of which may be avoiding long-time operation. Further studies including clinical trials to assess perioperative anti-sarcopenia treatments, are needed.

Effect of progressive sarcopenia during postoperative 6 months on long-term prognosis of completely resected lung cancer

Background

Preoperative sarcopenia has been indicated to be a potential prognostic factor for patients after complete resection of lung cancer. This study evaluated whether changes in the skeletal muscle mass index (SMI) over postoperative 6 months could predict long-term prognosis from 6 months after complete resection of non-small cell lung cancer (NSCLC).

Methods

This retrospective study analyzed data of 468 patients who underwent curative lobar resection for non-small cell lung cancer at our hospital. The 6-month postoperative change in SMI was calculated, and associations between clinicopathological factors (including the change in SMI) and postoperative mortality were examined.

Results

Rates of overall survival were 90.6% after 3 years and 80.7% after 5 years. The median 6-month change in SMI was -3.4% (range, -22.3% to 14.7%). Multivariate analysis revealed that poor outcomes were independently predicted by a large change in SMI, age, pathological stage, lymphovascular invasion, and a Brinkman index of ≥600. Through the analysis in training and validation sets, we determined a cut-off value of -9.9% for the 6-month postoperative change in SMI. Subgroup analysis showed that depletion of SMI during postoperative 6 months was a risk factor for poorer prognosis only in heavy smokers with a Brinkman index of ≥600.

Conclusions

A reduction in SMI during the 6 months after complete resection of non-small cell lung cancer significantly predicted prognosis, especially in heavy smokers. These results suggest that attention should be given to prevent the perioperative progression of sarcopenia after curative resection of lung cancer. Thoracic surgeons should take how to manage perioperatively against sarcopenia into consideration.

Psychosocial effects of cancer cachexia: a systematic literature search and qualitative analysis

CONTEXT

Cancer cachexia is debilitating and affects most patients with advanced cancer. Because treatment options are poor, the psychosocial effects of cancer cachexia always should be assessed and psychosocial support provided.

OBJECTIVES

To review the existing evidence of psychosocial effects of cancer cachexia with the aim of identifying factors that might be modified to improve outcomes.

METHODS

We carried out a systematic literature search in MEDLINE and Embase. The search string included key words for the topics "advanced cancer," "cancer cachexia," and "psychosocial effects." Publications were selected by two reviewers. The search was complemented by a hand search.

RESULTS

Nineteen studies were included. The available information revealed mechanisms leading to, various presentations of, and coping strategies for psychosocial effects of cancer cachexia in both patients and their carers. Not all those affected manage the effects of the condition constructively. A number of clinically important adverse reactions have been identified. The main causes for negative psychosocial effects are a lack of knowledge of the irreversible nature of cancer cachexia and unsuccessful attempts to increase body weight with altered patterns of nutritional intake. Depending on patients' and their carers' coping resources, psychosocial effects may escalate or decrease. Early identification of psychosocial effects creates the potential for psychosocial interventions that improve the quality of life of those affected. Our analysis engendered a broader conceptualization of the psychosocial effects of cancer cachexia, leading to a number of suggestions for psychosocial interventions with the potential for providing relief.

CONCLUSION

The concept of psychosocial effects in cancer cachexia has the potential to sensitize health care professionals to cachexia-related problems and inform their clinical management of the condition.

Why do anti-inflammatory therapies fail to improve insulin sensitivity?

Chronic inflammation occurs in obese conditions in both humans and animals. It also contributes to the pathogenesis of type 2 diabetes (T2D) through insulin resistance, a status in which the body loses its ability to respond to insulin. Inflammation impairs insulin signaling through the functional inhibition of IRS-1 and PPARγ. Insulin sensitizers (such as rosiglitazone and pioglitazone) inhibit inflammation while improving insulin sensitivity. Therefore, anti-inflammatory agents have been suggested as a treatment strategy for insulin resistance. This strategy has been tested in laboratory studies and clinical trials for more than 10 years; however, no significant progress has been made in any of the model systems. This status has led us to re-evaluate the biological significance of chronic inflammation in obesity. Recent studies have consistently asserted that obesity-associated inflammation helps to maintain insulin sensitivity. Inflammation stimulates local adipose tissue remodeling and promotes systemic energy expenditure. We propose that these beneficial activities of inflammation provide an underlying mechanism for the failure of anti-inflammatory therapy in the treatment of insulin resistance. Current literature will be reviewed in this article to present evidence that supports this viewpoint.

Definition and classification of cancer cachexia: an international consensus

To develop a framework for the definition and classification of cancer cachexia a panel of experts participated in a formal consensus process, including focus groups and two Delphi rounds. Cancer cachexia was defined as a multifactorial syndrome defined by an ongoing loss of skeletal muscle mass (with or without loss of fat mass) that cannot be fully reversed by conventional nutritional support and leads to progressive functional impairment. Its pathophysiology is characterised by a negative protein and energy balance driven by a variable combination of reduced food intake and abnormal metabolism. The agreed diagnostic criterion for cachexia was weight loss greater than 5%, or weight loss greater than 2% in individuals already showing depletion according to current bodyweight and height (body-mass index [BMI] <20 kg/m(2)) or skeletal muscle mass (sarcopenia). An agreement was made that the cachexia syndrome can develop progressively through various stages--precachexia to cachexia to refractory cachexia. Severity can be classified according to degree of depletion of energy stores and body protein (BMI) in combination with degree of ongoing weight loss. Assessment for classification and clinical management should include the following domains: anorexia or reduced food intake, catabolic drive, muscle mass and strength, functional and psychosocial impairment. Consensus exists on a framework for the definition and classification of cancer cachexia. After validation, this should aid clinical trial design, development of practice guidelines, and, eventually, routine clinical management.

Regulation of energy metabolism by inflammation: a feedback response in obesity and calorie restriction

Caloric restriction (CR), in the absence of malnutrition, delays aging and prevents aging-related diseases through multiple mechanisms. A reduction in chronic inflammation is widely observed in experimental models of caloric restriction. The low inflammation status may contribute to the reduced incidence of osteoporosis, Alzheimer's disease, cardiovascular diseases and cancer in the aging subjects. The association of caloric restriction with low inflammation suggests a role of energy accumulation in the origin of the chronic inflammation. This point is enforced by recent advances in obesity research. Abundant literature on obesity suggests that chronic inflammation is a consequence of energy accumulation in the body. The emerging evidence strongly supports that the inflammatory response induces energy expenditure in a feedback manner to fight against energy surplus in obesity. If this feedback system is deficient (Inflammation Resistance), energy expenditure will be reduced and energy accumulation will lead to obesity. In this perspective, we propose that an increase in inflammation in obesity promotes energy expenditure with a goal to get rid of energy surplus. A decrease in inflammation under caloric restriction contributes to energy saving. Inflammation is a mechanism for energy balance in the body. Inflammation resistance will lead to obesity. We will review the recent literature in support of the viewpoints.

Uncoupling of inflammation and insulin resistance by NF-kappaB in transgenic mice through elevated energy expenditure

To study the metabolic activity of NF-kappaB, we investigated phenotypes of two different mouse models with elevated NF-kappaB activities. The transcriptional activity of NF-kappaB is enhanced either by overexpression of NF-kappaB p65 (RelA) in aP2-p65 mice or inactivation of NF-kappaB p50 (NF-kappaB1) through gene knock-out. In these models, energy expenditure was elevated in day and night time without a change in locomotion. The mice were resistant to adulthood obesity and diet-induced obesity without reduction in food intake. The adipose tissue growth and adipogenesis were inhibited by the elevated NF-kappaB activity. Peroxisome proliferator-activator receptor gamma expression was reduced by NF-kappaB at the transcriptional level. The two models exhibited elevated inflammatory cytokines (tumor necrosis factor-alpha and interleukin-6) in adipose tissue and serum. However, insulin sensitivity was not reduced by the inflammation in the mice on a chow diet. On a high fat diet, the mice were protected from insulin resistance. The glucose infusion rate was increased more than 30% in the hyperinsulinemic-euglycemic clamp test. Our data suggest that the transcription factor NF-kappaB promotes energy expenditure and inhibits adipose tissue growth. The two effects lead to prevention of adulthood obesity and dietary obesity. The energy expenditure may lead to disassociation of inflammation with insulin resistance. The study indicates that inflammation may prevent insulin resistance by eliminating lipid accumulation.

Can the use of creatine supplementation attenuate muscle loss in cachexia and wasting?

PURPOSE OF REVIEW

Weight loss and low BMI due to an underlying illness have been associated with increased mortality, reduced functional capacity, and diminished quality of life. There is a need for well tolerated, long-term approaches to maintain body weight in patients with cachexia or wasting. The purpose of this review is to highlight the scientific and clinical evidence derived from the recent literature investigating the rationale for and potential medical use of creatine supplementation in patients with cachexia or wasting.

RECENT FINDINGS

Some studies have demonstrated that supplementation with creatine can increase creatine reserves in skeletal muscle and increase muscle mass and performance in various disease states that affect muscle size and function. The mechanisms underlying these effects are not clear. It has been suggested that creatine supplementation may increase intramuscular phosphocreatine stores and promote more rapid recovery of adenosine triphosphate levels following exercise, thus allowing users to exercise for longer periods or at higher intensity levels. Other hypothesized mechanisms include attenuation of proinflammatory cytokines, stimulation of satellite cell proliferation and upregulation of genes that promote protein synthesis and cell repair.

SUMMARY

Creatine is a generally well tolerated, low-cost, over-the-counter nutritional supplement that shows potential in improving lean body mass and functionality in patients with wasting diseases. However, placebo-controlled studies have shown variable effects, with improvements in some and not in others. Additional studies with longer follow-up are required to identify the populations that might benefit most from creatine supplementation.