A review of the effects of growth hormone changes on symptoms of frailty in the elderly with chronic kidney disease

Chronic kidney disease-related physical frailty and cognitive impairment: a systemic review

AIM

The objective of this review was to assess chronic kidney disease-related frailty and cognitive impairment, as well as their probable causes, mechanisms and the interventions.

METHODS

Studies from 1990 to 2015 were reviewed to evaluate the relationship between chronic kidney disease and physical frailty and cognitive impairment. Of the 1694 studies from the initial search, longitudinal studies (n = 22) with the keywords "Cognitive and CKD" and longitudinal or cross-sectional studies (n = 5) with the keywords "Frailty and CKD" were included in final analysis.

RESULTS

By pooling current research, we show clear evidence for a relationship between chronic kidney disease and frailty and cognitive impairment in major studies. Vascular disease is likely an important mediator, particularly for cognitive impairment. However, non-vascular factors also play an important role. Many of the other mechanisms that contribute to impaired cognitive function and increased frailty in CKD remain to be elucidated. In limited studies, medication therapy did not obtain the ideal effect. There are limited data on treatment strategies, but addressing the vascular disease risk factors earlier in life might decrease the subsequent burden of frailty and cognitive impairment in this population. Multidimensional interventions, which address both microvascular health and other factors, may have substantial benefits for both the cognitive impairments and physical frailty in this vulnerable population.

CONCLUSIONS

Chronic kidney disease is a potential cause of frailty and cognitive impairment. Vascular and non-vascular factors are the possible causes. The mechanism of chronic kidney disease-induced physical frailty and cognitive impairment suggests that multidimensional interventions may be effective therapeutic strategies in the early stage of chronic kidney disease. Geriatr Gerontol Int 2017; 17: 529-544.

End-stage renal disease in the elderly: dialysis or conservative management?

The challenges of health care in an aging population are mirrored in the field of nephrology, in which an increasing proportion of the population has chronic kidney disease (CKD) and end-stage renal disease requiring dialysis. The need for dialysis negatively influences survival and health-related quality of life (HRQoL) in all age groups, but particularly in the elderly, raising the issue of withholding dialysis and emphasizing conservative management of CKD in some patients. Increased mortality is seen in dialysis patients who are elderly, have significant comorbidities, and have poor functional status. In such patients, the option of palliative care should be discussed in order to focus on HRQoL in the physical, psychological, and social domains. Although survival among the elderly who forgo dialysis is worse than those who begin dialysis, hospitalizations and HRQoL may be better, especially if the CKD-associated complications are appropriately addressed through effective palliative care.

A network pharmacology approach to understanding the mechanisms of action of traditional medicine: Bushenhuoxue formula for treatment of chronic kidney disease

Traditional Chinese medicine (TCM) has unique therapeutic effects for complex chronic diseases. However, for the lack of an effective systematic approach, the research progress on the effective substances and pharmacological mechanism of action has been very slow. In this paper, by incorporating network biology, bioinformatics and chemoinformatics methods, an integrated approach was proposed to systematically investigate and explain the pharmacological mechanism of action and effective substances of TCM. This approach includes the following main steps: First, based on the known drug targets, network biology was used to screen out putative drug targets; Second, the molecular docking method was used to calculate whether the molecules from TCM and drug targets related to chronic kidney diseases (CKD) interact or not; Third, according to the result of molecular docking, natural product-target network, main component-target network and compound-target network were constructed; Finally, through analysis of network characteristics and literature mining, potential effective multi-components and their synergistic mechanism were putatively identified and uncovered. Bu-shen-Huo-xue formula (BSHX) which was frequently used for treating CKD, was used as the case to demonstrate reliability of our proposed approach. The results show that BSHX has the therapeutic effect by using multi-channel network regulation, such as regulating the coagulation and fibrinolytic balance, and the expression of inflammatory factors, inhibiting abnormal ECM accumulation. Tanshinone IIA, rhein, curcumin, calycosin and quercetin may be potential effective ingredients of BSHX. This research shows that the integration approach can be an effective means for discovering active substances and revealing their pharmacological mechanisms of TCM.

A pilot trial to predict frailty syndrome: the Japanese Health Research Volunteer Study

Most definitions of frailty utilize US populations in their development. The concept of frailty has not been well studied in Japan, which has the largest percentage of older patients (per capita) in the world. We created a 5-year prospective cohort study of community-dwelling older Japanese adults. Participants were not frail at baseline, based on our definition adapted from the Canadian Study for Health and Aging Clinical Frailty Scale. Participants underwent a comprehensive geriatric assessment (CGA) at baseline, and final assessments were either in person or via mailed survey. We enrolled 407 individuals (184 men, mean age 78 ± 4 years; 223 women, mean age 77 ± 4 years). Sixty-five participants met criteria for frailty by the end of the study. In univariate analyses, eighteen separate parameters were associated with frailty, some of which included: age, gender, handgrip, timed walk, systolic blood pressure, pulse pressure, cognitive status, living alone, and hearing deficits. In multivariate analyses, the following elements remained associated with frailty: timed walk, pulse pressure, cognition deficits and hearing deficits. We established cut-off points for timed walk (5m/3s) and pulse pressure (60 mmHg). We then created a simple additive score for these four factors (present = 1; absent = 0). A score of 0 had a 93% negative predictive value for frailty while a score of 4 had a 70% positive predictive value. While further study is needed, this work creates an easy-to-administer tool that may be generalizable to other populations.

Is chronic kidney disease in older people a new geriatric giant?

The global population is aging, and the number of people above the age of 85 years is growing faster than any other age group. There is an age-related decline in kidney function; however, not all individuals will develop chronic kidney disease (CKD) with advancing age. Those who are genetically predisposed and exposed to lifetime cardiovascular risk factors are likely to develop systemic atherosclerosis and CKD as a part of its manifestation. CKD promotes poor health through its association with inflammation and oxidative stress. Malnutrition, weight loss and sarcopenia are common in CKD patients, leading to poor outcomes, such as physical and cognitive dysfunction, manifesting as major geriatric syndromes. Frailty is likely to be one of the underlying processes that leads to the clinical manifestations of geriatric syndromes in patients with CKD. Therefore, functional outcomes, such as cognition and physical functioning, might be more relevant outcomes to older patients with CKD. Interventions should be developed and assessed in terms of maintaining quality rather than quantity of life before disability develops.

Thyroid hormone abnormalities and frailty in elderly patients with chronic kidney disease: a hypothesis

Thyroid hormones play a crucial role in the metabolic activities of adults, affecting almost every organ system. All types of thyroid diseases are encountered in the elderly. As symptoms and signs of thyroid diseases may overlap with what is considered to be "normal aging," the presence of a thyroid disorder may go undiagnosed in the elderly. This potential problem is further compounded in elderly patients with chronic kidney disease (CKD), where the presence of an underlying hormonal problem such as hypothyroidism may be erroneously attributed to multiple comorbidities, the aging process, or the kidney disease. Frailty is being recognized as a contributing factor to the poor outcomes (hospitalization and high mortality) in elderly patients with CKD. Predisposing factors leading to frailty in elderly with CKD such as increased inflammatory markers, anemia, low testosterone, sarcopenia, and depression are associated with thyroid hormonal abnormalities. These associations are remarkable and raise the question of whether routine monitoring and screening for thyroid hormone changes in elderly CKD patients might be helpful in identifying reversible causes of frailty. In this review, we will focus on the associations between thyroid hormone abnormalities and the predisposing factors of frailty in elderly patients with CKD. If a cause-effect relationship of thyroid hormone abnormalities and factors predisposing to frailty in CKD patients is established, identification and treatment of thyroid abnormalities in this population would assume increased importance.

The growth hormone receptor: mechanism of activation and clinical implications

Growth hormone is widely used clinically to promote growth and anabolism and for other purposes. Its actions are mediated via the growth hormone receptor, both directly by tyrosine kinase activation and indirectly by induction of insulin-like growth factor 1 (IGF-1). Insensitivity to growth hormone (Laron syndrome) can result from mutations in the growth hormone receptor and can be treated with IGF-1. This treatment is, however, not fully effective owing to the loss of the direct actions of growth hormone and altered availability of exogenous IGF-1. Excessive activation of the growth hormone receptor by circulating growth hormone results in gigantism and acromegaly, whereas cell transformation and cancer can occur in response to autocrine activation of the receptor. Advances in understanding the mechanism of receptor activation have led to a model in which the growth hormone receptor exists as a constitutive dimer. Binding of the hormone realigns the subunits by rotation and closer apposition, resulting in juxtaposition of the catalytic domains of the associated tyrosine-protein kinase JAK2 below the cell membrane. This change results in activation of JAK2 by transphosphorylation, then phosphorylation of receptor tyrosines in the cytoplasmic domain, which enables binding of adaptor proteins, as well as direct phosphorylation of target proteins. This model is discussed in the light of salient information from closely related class 1 cytokine receptors, such as the erythropoietin, prolactin and thrombopoietin receptors.