Intralipid infusion combined with propranolol administration has favorable metabolic effects in elderly malnourished cancer patients

Hypermetabolism and symptom burden in advanced cancer patients evaluated in a cachexia clinic

BACKGROUND

Elevated resting energy expenditure (REE) may contribute to weight loss and symptom burden in cancer patients.

AIMS

The aim of this study was to compare the velocity of weight loss, symptom burden (fatigue, insomnia, anxiety, and anorexia-combined score as measured by the Edmonton Symptom Assessment Score), high-sensitivity C-reactive protein, and survival among cancer patients referred to a cachexia clinic with hypermetabolism, elevated REE > 110% of predicted, with normal REE.

METHODS

A retrospective analysis of 60 advanced cancer patients evaluated in a cachexia clinic for either >5% weight loss or anorexia who underwent indirect calorimetry to measure REE. Patients were dichotomized to either elevated or normal REE. Descriptive statistics were generated, and a two-sample Student's t-tests were used to compare the outcomes between the groups. Kaplan-Meier and Cox regression methodology were used to examine the survival times between groups.

RESULTS

Thirty-seven patients (62%) were men, 41 (68%) were White, 59 (98%) solid tumours, predominantly 23 gastrointestinal cancers (38%), with a median age of 60 (95% confidence interval 57.0-62.9). Thirty-five patients (58%) were hypermetabolic. Non-Caucasian patients were more likely to have high REE [odds ratio = 6.17 (1.56, 24.8), P = 0.01]. No statistical difference regarding age, cancer type, gender, active treatment with chemotherapy, and/or radiation between hypermetabolic and normal REE was noted. The velocity of weight loss over a 3 month period (-8.5 kg vs. -7.2 kg, P = 0.68), C-reactive protein (37.3 vs. 55.6 mg/L, P = 0.70), symptom burden (4.2 vs. 4.5, P = 0.54), and survival (288 vs. 276 days, P = 0.68) was not significantly different between high vs. normal REE, respectively.

CONCLUSION

Hypermetabolism is common in cancer patients with weight loss and noted to be more frequent in non-Caucasian patients. No association among velocity of weight loss, symptom burden, C-reactive protein, and survival was noted in advanced cancer patients with elevated REE.

The roles of beta-adrenergic receptors in tumorigenesis and the possible use of beta-adrenergic blockers for cancer treatment: possible genetic and cell-signaling mechanisms

Cancer is the leading cause of death in the USA, and the incidence of cancer increases dramatically with age. Beta-adrenergic blockers appear to have a beneficial clinical effect in cancer patients. In this paper, we review the evidence of an association between β-adrenergic blockade and cancer. Genetic studies have provided the opportunity to determine which proteins link β-adrenergic blockade to cancer pathology. In particular, this link involves the major histocompatibility complex class II molecules, the renin-angiotensin system, transcription factor nuclear factor-kappa-light-chain-enhancer of activated B cells, poly(ADP-ribose) polymerase-1, vascular endothelial growth factor, and the reduced form of nicotinamide adenine dinucleotide phosphate oxidase. Beta-adrenergic blockers also exert anticancer effects through non-genomic factors, including matrix metalloproteinase, mitogen-activated protein kinase pathways, prostaglandins, cyclooxygenase-2, oxidative stress, and nitric oxide synthase. In conclusion, β-adrenergic blockade may play a beneficial role in cancer treatment. Additional investigations that examine β-adrenergic blockers as cancer therapeutics are required to further elucidate this role.

Neural control of the anorexia-cachexia syndrome

The anorexia-cachexia syndrome is a debilitating clinical condition characterizing the course of chronic diseases, which heavily impacts on patients' morbidity and quality of life, ultimately accelerating death. The pathogenesis is multifactorial and reflects the complexity and redundancy of the mechanisms controlling energy homeostasis under physiological conditions. Accumulating evidence indicates that, during disease, disturbances of the hypothalamic pathways controlling energy homeostasis occur, leading to profound metabolic changes in peripheral tissues. In particular, the hypothalamic melanocortin system does not respond appropriately to peripheral inputs, and its activity is diverted largely toward the promotion of catabolic stimuli (i.e., reduced energy intake, increased energy expenditure, possibly increased muscle proteolysis, and adipose tissue loss). Hypothalamic proinflammatory cytokines and serotonin, among other factors, are key in triggering hypothalamic resistance. These catabolic effects represent the central response to peripheral challenges (i.e., growing tumor, renal, cardiac failure, disrupted hepatic metabolism) that are likely sensed by the brain through the vagus nerve. Also, disease-induced changes in fatty acid oxidation within hypothalamic neurons may contribute to the dysfunction of the hypothalamic melanocortin system. Ultimately, sympathetic outflow mediates, at least in part, the metabolic changes in peripheral tissues. Other factors are likely involved in the pathogenesis of the anorexia-cachexia syndrome, and their role is currently being elucidated. However, available evidence shows that the constellation of symptoms characterizing this syndrome should be considered, at least in part, as different phenotypes of common neurochemical/metabolic alterations in the presence of a chronic inflammatory state.

The cytokine basis of cachexia and its treatment: are they ready for prime time?

Cachexia is a hypercatabolic condition that is often associated with the terminal stages of many diseases, in which the patient's resting metabolic rate is high and loss of muscle and fat tissue mass occur at an alarming rate. The patient also usually has concurrent anorexia, amplifying the wasting syndrome that is cachexia. The greater the extent of cachexia (regardless of underlying disease), the worse the prognosis. Efforts to treat cachexia over the years have fallen short of satisfactorily reversing the wasting syndrome. This article reviews the pathophysiology of cachexia, enumerating the different pro-inflammatory cytokines that contribute to the syndrome and attempting to illustrate their interwoven pathways. We also review the different treatments that have been explored, as well as the recent literature addressing the use of anti-cytokine therapy to treat cachexia.

Pharmacological Treatment of Geriatric Cachexia: Evidence and Safety in Perspective

Anticachexic or antisarcopenic medications are prescribed worldwide for geriatric patients with poor appetite and associated weight loss. They represent a valuable treatment option for managing cachexia. However, the well-publicized adverse reports about these medications in acquired immunodeficiency syndrome (AIDS) and in the cancer population has led to some concern and much subsequent discussion over the safety of these medications being used in geriatric population. This review looks at the evidence in relation to the benefits and risks of these medications and discusses what we know about their use in the geriatric population.

Quantifying cardiac sympathetic and parasympathetic nervous activities using principal dynamic modes analysis of heart rate variability

The ratio between low-frequency (LF) and high-frequency (HF) spectral power of heart rate has been used as an approximate index for determining the autonomic nervous system (ANS) balance. An accurate assessment of the ANS balance can only be achieved if clear separation of the dynamics of the sympathetic and parasympathetic nervous activities can be obtained, which is a daunting task because they are nonlinear and have overlapping dynamics. In this study, a promising nonlinear method, termed the principal dynamic mode (PDM) method, is used to separate dynamic components of the sympathetic and parasympathetic nervous activities on the basis of ECG signal, and the results are compared with the power spectral approach to assessing the ANS balance. The PDM analysis based on the 28 subjects consistently resulted in a clear separation of the two nervous systems, which have similar frequency characteristics for parasympathetic and sympathetic activities as those reported in the literature. With the application of atropine, in 13 of 15 supine subjects there was an increase in the sympathetic-to-parasympathetic ratio (SPR) due to a greater decrease of parasympathetic than sympathetic activity ( P = 0.003), and all 13 subjects in the upright position had a decrease in SPR due to a greater decrease of sympathetic than parasympathetic activity ( P < 0.001) with the application of propranolol. The LF-to-HF ratio calculated by the power spectral density is less accurate than the PDM because it is not able to separate the dynamics of the parasympathetic and sympathetic nervous systems. The culprit is equivalent decreases in both the sympathetic and parasympathetic activities irrespective of the pharmacological blockades. These findings suggest that the PDM shows promise as a noninvasive and quantitative marker of ANS imbalance, which has been shown to be a factor in many cardiac and stress-related diseases.

Role of beta3-adrenergic receptors in the action of a tumour lipid mobilizing factor

Induction of lipolysis in murine white adipocytes, and stimulation of adenylate cyclase in adipocyte plasma membranes, by a tumour-produced lipid mobilizing factor, was attenuated by low concentrations (10(-7)--10(-5)M) of the specific beta3-adrenoceptor antagonist SR59230A. Lipid mobilizing factor (250 nM) produced comparable increases in intracellular cyclic AMP in CHOK1 cells transfected with the human beta3-adrenoceptor to that obtained with isoprenaline (1 nM). In both cases cyclic AMP production was attenuated by SR59230A confirming that the effect is mediated through a beta3-adrenoceptor. A non-linear regression analysis of binding of lipid mobilizing factor to the beta3-adrenoceptor showed a high affinity binding site with a Kd value 78 +/- 45 nM and a B(max) value (282 +/- 1 fmole mg protein(-1)) comparable with that of other beta3-adrenoceptor agonists. These results suggest that lipid mobilizing factor induces lipolysis through binding to a beta3-adrenoceptor.

Cancer anorexia and cachexia

Patients with cancer cachexia experience a profound wasting of adipose tissue and lean body mass. Anorexia, although often present, is insufficient to account for tissue wasting because 1) cachexia involves massive depletion of skeletal muscle that does not occur during anorexia, 2) nutritional supplementation cannot replenish the loss of lean body mass, 3) cachexia can occur without anorexia, and 4) food intake might be normal for the lower weight of the cancer patient. Anorexia can arise from 1) decreased taste and smell of food, 2) early satiety, 3) dysfunctional hypothalamic membrane adenylate cyclase, 4) increased brain tryptophan, and 5) cytokine production. Appetite stimulants such as cyproheptadine, medroxyprogesterone acetate, and megestrol acetate do not significantly improve lean body mass. Tumor products might be more important in the development of cachexia. Cachectic patients excrete in their urine a lipid-mobilizing factor that directly stimulates lipolysis in a cyclic AMP-dependent manner and increases energy expenditure. Loss of skeletal muscle in cachexia is caused by upregulation of the ubiquitin-proteasome catabolic pathway. Cachexia-inducing tumors elaborate a sulfated glycoprotein, which directly initiates protein catabolism in skeletal muscle. The action of this proteolysis-inducing factor is attenuated by the polyunsaturated fatty acid eicosapentaenoic acid, which is also effective in preventing loss of skeletal muscle in cancer patients. Antagonists of tumor catabolic factors will provide important new agents in the treatment of cancer cachexia.

Neurochemical mechanisms for cancer anorexia

Under normal conditions, the homeostasis of energy intake is maintained in the hypothalamus by 1) transducing metabolic and sensorial inputs arising from the periphery into neuronal response, 2) integrating the information originating from different tissues, and 3) triggering the appropriate feeding responses. If cancer anorexia is considered a disruption of the physiologic mechanisms controlling energy intake, it is conceivable that its pathogenesis may lie in an abnormal input of information to the hypothalamus, its defective transduction and integration, or the induction of exaggerated and inappropriate feeding responses. Currently available data suggest that the pathogenesis of cancer anorexia is multifactorial and involves most of the neuronal signaling pathways modulating energy intake. Thus, a number of factors has been proposed as putative mediators of cancer anorexia, including hormones (e.g., leptin), neuropeptides (e.g., neuropeptide Y), cytokines (e.g., interleukin-1, interleukin-6, tumor necrosis factor), and neurotransmitters (e.g., serotonin and dopamine). However, it is unlikely that they represent separate and distinct pathogenic mechanisms; rather, it appears that close interrelationships may exist among them. In line with this reasoning, consistent experimental and human data suggest that hypothalamic monoaminergic neurotransmission and serotonergic activity in particular may represent a major target on which different anorexia-related factors converge. Thus, interfering pharmacologically with hypothalamic serotonin synthesis and activity has been tested as a therapeutic strategy in anorectic cancer patients with encouraging results. However, more clinical options will be available by revealing the complex interactions between the many factors participating in controlling energy intake under normal and pathologic conditions. Further, modulation of hypothalamic activity also might result in reduced catabolic signals to skeletal muscles, thus improving the cachexia associated with cancer.

Do patients with nonmetastatic non-small cell lung cancer demonstrate altered resting energy expenditure?

BACKGROUND

The cancer cachexia syndrome occurs in patients with non-small cell lung cancer (NSCLC) and includes elevated resting energy expenditure (REE). This increase in REE leads to weight loss, which in turn confers a poor prognosis. This study was undertaken to determine whether the cancer cachexia syndrome occurs in patients with nonmetastatic NSCLC.

METHODS

In this case-control study, 18 patients with nonmetastatic NSCLC (stages IA to IIIB) were matched to healthy controls on age (+/- 5 years), gender, and body mass index (+/- 3 kg/m2). Only 4 cancer patients had experienced > 5% weight loss. Cancer patients and controls were compared on the basis of: (1) unadjusted REE, as measured by indirect calorimetry; (2) REE adjusted for lean body mass, as measured by dual x-ray absorptiometry; (3) REE adjusted for body cell mass, as measured by potassium-40 measurement; and (4) REE adjusted for total body water, as measured by tritiated water dilution.

RESULTS

We observed no significant difference in unadjusted REE or in REE adjusted for total body water. However, with separate adjustments for lean body mass and body cell mass, cancer patients manifested an increase in REE: mean difference +/- standard error of the mean: 140+/-35 kcal/day (p = 0.001) and 173+/-65 kcal/day (p = 0.032), respectively. Further adjustment for weight loss yielded similarly significant results.

CONCLUSIONS

These results suggest that the cancer cachexia syndrome occurs in patients with nonmetastatic NSCLC and raise the question of whether clinical trials that target cancer cachexia should be initiated before weight loss.