Interdisciplinary topics in gerontology and geriatrics最新文献

The increase in the prevalence of obesity represents a worldwide phenomenon which is associated with several chronic diseases. In this review, we summarize published data showing how obesity, alone or together with the metabolic syndrome, induces defects in B cells similar to those induced by aging, contributes to systemic and B cell intrinsic inflammation and increases the secretion of autoimmune antibodies. We show that obese individuals contract more bacterial, viral, and fungal infections as compared to lean controls. These include periodontal, cutaneous, gastric, and respiratory tract infections, as well as postsurgical infections occurring after solid organ transplantation and surgeries for weight loss. Moreover, because obese individuals have a compromised immune system, they respond poorly to vaccination against influenza, hepatitis B, tetanus, and rabies. The results in this review highlight the importance to vaccinate individuals with obesity and/or with metabolic syndrome to prevent morbidity from vaccine-preventable diseases.

The following chapter is focused on the impact of comorbidities on the effectiveness of vaccination in older persons. Relevant comorbidities are cardiovascular diseases like hypertension, coronary artery disease or congestive heart failure, which lead to reduction of vaccine immunogenicity; or chronic obstructive pulmonary disease with a decline in lung function and a higher risk for pneumonia or infections due to influenza. End-stage renal disease has a high impact on developing infections and causes immune dysfunction over all parts of the immune system. Depression and dementia as well as psychological stress are associated with poor antibody response and a higher range of inflammation markers. Chronic inflammatory processes like rheumatoid arthritis also alter the immune system. In addition, geriatric syndromes and lowered functional status have implications for the vaccination response. Malnutrition is characterized by depletion of structural and functional proteins. This leads to a low antibody response. Negative immunomodulatory effects are also observed in vitamin D insufficiency. Frailty as well is associated with immunological changes and lowered performance in the activities of daily living, but moderate physical activity improves immune function.

Herpes zoster (HZ; shingles) results from reactivation of varicella-zoster virus (VZV) after primary infection as varicella (chicken pox). It affects mainly older adults and people with immunocompromising diseases or treatments. The most common complication is postherpetic neuralgia (PHN), which has significant adverse effects on quality of life and activities of daily living. Since PHN cannot be prevented once HZ has occurred, and treatment is only modestly successful and is associated with significant side effects, the recent introduction of an effective vaccine is an important achievement. This new vaccine, which combines a single VZV glycoprotein (gE) and a multicomponent adjuvant, is superior to the previously available live attenuated VZV vaccine. The recombinant adjuvanted vaccine is remarkably effective in restoring the protective T cell-mediated immunity required to prevent HZ. Its clinical efficacy is much greater than that observed with other vaccines for older individuals affected by immune senescence, and its safety profile is very acceptable. It has been recommended in the USA and Canada for people who are 50 years of age and older. The immunogenicity and safety of this vaccine in severely immunocompromised individuals, such as after chemotherapy for malignancy, after solid organ or stem cell transplant, and in people with HIV are being studied.

Older people have reduced immune responses to infection and vaccination. B cell activation is key for the efficacy of the vaccine response, but there are several age-related changes in B cells which may contribute to the loss of vaccine efficacy. Different subpopulations of B cells have different functions and phenotypes. These populations can change as we age; older people have been shown to have fewer "IgM memory" cells, regulatory B cells and plasma cells and more IgD-CD27- "double-negative" and "age-related B cells." While the overall quantity of antibody in the blood does not change, the quality of the B cell response changes; producing less specific antibodies upon challenge and more autoreactive antibodies. This could be due to changes in selection pressures, as has been demonstrated by repertoire sequencing of different subsets of B cells at different ages. Other changes in antibody repertoire are seen, including greater levels of IgG2 in older people and altered IgG1 IGHV gene usage. Since B cells rely on their environment for efficient responses, some of these changes may be due to age-related changes in accessory cells/signals. Other changes appear to be intrinsic to older/aged B cells themselves, such as their tendency to produce greater levels of inflammatory cytokines.

Determining the optimal vaccination strategy for the protection of the elderly population against pneumococcal disease remains a challenge. Older adults are, second to young infants, most susceptible to become colonized and invaded by Streptococcus pneumoniae, causing serious disease such as bacteremic pneumonia, sepsis, and meningitis. In an era with increasing antimicrobial resistance and the growing susceptible population of aged adults, S. pneumoniae is a priority bacterial pathogen for research and development of new intervention strategies. While elderly indirectly profit from infant immunization programs through herd immunity, vaccination of older age groups can offer more direct protection. Two types of pneumococcal vaccines for adults, both based on capsular polysaccharide serotypes, are currently available but have limitations, such as short-lived protection or limited serotype coverage. These vaccine limitations and the biological aging of the immune system call for novel vaccination strategies for the older adults. Here, we highlight how host-pathogen interactions, immune protection, and effectiveness of currently available vaccines shift with increasing age, and how future pneumococcal vaccine strategies could be tailored for the elderly.

People who travel to countries where they are at risk of contracting specific infections often need specific vaccines. To make correct recommendations in this respect several points have to be considered. The state of health of the traveler should be known as well as his or her destination and travel style. Very important, however, is the age of the traveler. As advancing age leads to changes in the immune system, in older individuals many infections are more severe. On the other hand, most vaccines are less immunogenic in the elderly. In this chapter, we will discuss which vaccines are necessary for older travelers visiting (mainly) tropical and subtropical countries, how these vaccines have to be used, and if perhaps their use has to be altered in older individuals. First, standard vaccinations will be addressed. When the immunization state of the individual is incomplete because certain vaccinations are expired or missing, it has to be updated. Vaccinations against tetanus, diphtheria, influenza, pneumococcal diseases, measles, and poliomyelitis have to be considered in this respect, because the risk of getting infected with these diseases in tropical and subtropical regions or in regions with poor hygienic conditions is often higher or at least the same as in industrialized countries. The second and main part of this chapter contains the typical travel vaccines. We will deal with vaccinations against cholera, hepatitis A and B, Japanese encephalitis, invasive meningococcal diseases, rabies, typhoid fever, and yellow fever. Clinical courses and epidemiology of the different infections are presented. The respective vaccines are discussed in detail, especially their efficiency in older individuals as far as data are available in this respect. Finally, recommendations for their use in older travelers will be given.

Aging is associated with changes in the immune system. Both (innate and adaptive) arms of the immune system are involved. Natural killer (NK) cells are part of the innate immune system. They participate in host defense by eliminating cells that are virally infected, transformed, or senescent. They are also able to modulate the adaptive part of the immune system. As all cells, NK cells are subjected to changes with aging, which affects both their phenotype and functions. Aging is associated with various latent chronic viral infections, and the most significant among them is CMV. It is difficult to distinguish between the influence of CMV infection and that of aging itself on the NK cell properties. Recently, NK cells have been shown to be an important player in vaccine efficacy, which is also decreased with aging. In this chapter, we describe age-related changes in NK cells and their possible influence on the efficacy of vaccination in old age.

The connection between palliative care and HIV infection has deep and wide roots in the United States that go back to the time when many gay men in the early 1980s were dying from a disease we knew little about, and there was no way to help but to alleviate symptoms in hospice and end of life centers across the United States. More individuals (adults and children), families, and communities attribute the success of antiretroviral therapies and other therapeutic approaches to advancing quality of life and life itself today. The identity of HIV, like many 'life-threatening illness with no cure' has evolved as a 'chronic' condition with a longer time period to address physical, social, and emotional experiences that may concern those living with HIV infection. Chronic conditions create an opportunity for healthcare providers from all types of disciplines to rethink and retool their knowledge and skills, to have conversations with those affected by HIV infection as to what they would ideally want in addressing their care needs; care needs that are now complicated by comorbid conditions of aging and healthcare reimbursement that uniquely intersect with HIV infection. This chapter addresses the current relevance of palliative care in HIV history, both nationally and internationally, and offers ideas for health professionals to use a multidisciplinary integration of knowledge to not just cure but align 'cure and care' toward healing action while being present to others from their perspective and values.

Sexuality is an important aspect of health across the lifespan and includes sex, gender identities, sexual orientation, intimacy, pleasure, reproduction, and free from coercion and discrimination. In 2010, individuals 50 years and older living with HIV in the US made up 8.5 per 100,000 persons affected by the virus, with African Americans accounting for 46% of seroconversion in the same year, which was 10.7 times greater than Whites. African American women are particularly at-risk. Although there are many promising HIV prevention interventions to date, there are few that focus specifically on older adults. This chapter raises methodological concerns in research that focuses on sexual health of older adults living with HIV infection and special concerns regarding the older adult population's sexual health risk and suggested clinical interventions.

Persons surviving to older ages with HIV/AIDS often face an accelerated aging accompanied by increased comorbidity and decline in health and function. In this chapter, we review the process of disablement among persons aging with HIV/AIDS, from chronic conditions to impairments and functional limitations, leading to disability. Chronic immune activation related to chronic HIV infection may contribute to early development of chronic conditions that are common in older adults resulting in premature disablement. Anatomical and physiological changes related to the aging process make people vulnerable to physical and cognitive impairments. In old age, quality of life depends mainly on avoidance and management of age-associated diseases rather than chronological parameters. Interventions to manage chronic conditions associated with aging may have a significant impact on quality of life in older persons with HIV infection. Because of the complexity of physical and cognitive impairments among persons aging with HIV infection, a range of supports and interventions will be needed to effectively address the problem of disablement in this population.