Reducing Hospitalization in the Elderly Population
Practice Issue or Problem in Advanced Practice Nursing
Immunization has been regarded as the keystone of influenza-linked mortality and morbidity prevention (Dominguez et al. 2016). Inactivated Influenza Vaccine’s efficacy in elderly individuals has been studied; a majority of scholars strongly recommend immunization in individuals aged 65+ (Dawood et al. 2014). Existing vaccines are given for the purpose of inducing serum anti-hemagglutinin antibodies to avoid ailment and infection resulting from an attack of natural influenza. Administration of annual influenza shots to vulnerable persons continues to be practiced on a widespread scale, with aged persons (i.e., 65+ years of age) being the key target population. Trivalent inactivated vaccines for influenza are deemed to be efficient as well as economical. But despite extensive influenza inoculation drives, aged inpatients are increasingly seen in hospitals, for severe cardiovascular and respiratory issues, in the course of recent yearly national outbreaks of influenza (Lang et al. 2012).
Background Information/Clinical Significance
Despite extensively available influenza inoculation initiatives, poor vaccination coverage rates continue to be experienced; the nation’s health sector fails to perform up to WHO targets for its vaccine coverage. This, indeed, partly accounts for influenza infection persisting as a key global public health issue. A National Institutes of Health study’s authors arrived at the conclusion that seasonal spells of influenza annually accounted for 41,000 deaths, and over 200,000 hospitalizations; further, influenza constituted the 7th key cause of mortality. Influenza-related mortality and morbidity depicts highest concentration among individuals aged 65+ as this group is more vulnerable to developing complications. Estimates for 2012-13 reveal that influenza immunization showed moderate effectiveness in decreasing hospitalizations because of respiratory complications and ailments (Fry et al. 2014). Researchers have also revealed that aged persons, particularly persons diagnosed with immunological disorders or chronic ailments, accounted for nine out of ten deaths linked to influenza. But significant uncertainties exist with regard to influenza-linked hospitalization burden in aged persons (Goldstein et al. 2015).
The common belief is that existing influenza vaccines prove effective in the prevention of elderly individuals’ (aged 65+) hospitalizations. But although trivalent inactivated vaccines for influenza avert lab-tested and -confirmed influenza among roughly 70 to 90% of fit adults in cases where the circulating virus and vaccine are antigenically identical, only a vague picture is presented in case of elderly persons. This greatly restricts randomized clinical trials’ (RCTs’) effectiveness in informing clinicians of the advantages of inoculation when it comes to avoiding hospitalization. A Netherlands-based placebo-controlled RCT performed in the course of the 1991-92 flu spell is considered the biggest and best planned study in this regard A total of 1838 fit volunteers who were aged sixty years or more received either the trivalent inactivated vaccine for influenza or a placebo, at random. Following age-wise stratification, the research team estimated 57% influenza vaccination success in participants aged between 60 and 69 years; however, the vaccine was successful only in 23% of participants in the 70+ years, age-group. The above finding indicates that vaccine impacts reduce further with age, and this, in part, reflects age-related immune system changes (Lang et al. 2012).
Thus, existing influenza vaccine success estimations are chiefly gleaned from observational research, often employing research database or healthcare service utilization information. Drawing on the meta-analyses that summarize such estimations, this study will attempt at examining the efficiency of extant influenza vaccine plans in alleviating future hospitalization risks among aged individuals (65+ years of age) compared to non-inoculated individuals. Moreover, the study will take into account present and future influenza vaccine success optimization strategies in this high-risk group.
Search Strategy
The study, in an attempt at the identification of every meta-analysis assessing influenza vaccine success among aging/elderly people, involved an electronic literature search of databases through Ovid Technologies (PUBMED, EMBASE, MEDLINE) using the keyword combinations listed below: “influenza vaccine” [Meshed] OR “vaccine” and “influenza” [All Fields]. The right publications out of this search were chosen based on research work title, body and abstract. The outline was limited to trivalent inactivated vaccines for influenza. The study only took into consideration RCTs having clinical endpoints (no intervention/placebo against efficacy) (Lang et al. 2012).
Integration and Synthesis of Evidence
Presentation of Evidence
A Spain-based research by Dominguez and coworkers which evaluated 1038 non-immunized and immunized individuals found low inoculation rates in the country; the recommendation was to increase immunization for preventing aged individuals’ hospitalization (2016). Matias and coworkers’ research scrutinized information gleaned from British national databases, concentrating particularly on influenza-linked hospitalizations and mortality from 1997 to 2009 (2016). Study authors recorded highest hospitalization and mortality rates in the >75 years age group (131 deaths and 252 hospitalizations per 100,000 individuals). Additional scrutiny of the vaccine’s efficacy among elderly persons (aged 65+) reviewed 64 research works in total (randomized, cohort, case-control and quasi-randomized researches evaluating success against lab-confirmed cases of influenza or similar ailments). Influenza vaccine efficacy in fighting similar diseases was found to be 23%, while it was deemed as non-significant when it came to lab-confirmed influenza (Lang et al. 2012).
In highly vulnerable aged individuals, owing to comorbid ailments, vaccination proved to be 49% successful in preventing hospital admission and 29% successful in mortality prevention. Therefore, when efficacy of influenza vaccine in adult subjects is stratified based on health status as well as age, another picture surfaces with respect to aged persons. In fact, in a majority of observational researches, underlying illness adjustments led to further growths in influenza vaccine success estimates (Lang et al. 2012).
Critique of Evidence
Although administrative datasets have been considered effective means of gauging the efficacy of influenza vaccine, this will likely be susceptible to problematic bias, and hence, estimate validity derived thus seems to be doubtful. Likewise, observational immunogenicity researches apparently fail to present more explicit and sounder results. The importance of a premature reduction in response of primary antibodies, observed within the elderly age-group as compared to younger individuals is another highly disputed topic. Furthermore, both lines of approach display acute methodological failings, namely, disparity in influenza case definition, application of diverse clinical endpoints, probable bias impacting influenza efficacy estimations (inclusion of subjects suffering from conditions impacting immune response, already vaccinated individuals, and individuals depicting high titers before inoculation) and poor protection correlates within immunogenicity research (Lang et al. 2012).
Identification of Themes across Studies
Shared research themes include: well-matched influenza vaccines helped prevent hospitalization, pneumonia, and pneumonia or influenza related mortalities; well-matched influenza vaccines helped prevent pneumonia and influenza linked hospitalization as well as all-cause death; and following confounder adjustment, improved vaccine efficacy was observed for pneumonia/influenza, cardiac and respiratory ailment hospitalizations as well as all-cause deaths. Further, outcomes revealed that immunization proved most effective in case of people residing within institutional settings; modest vaccine efficacy was noted within community settings (Lang et al. 2012).
Comparative Evaluation of the Evidence to Practice
Comparison of Findings with Personal Practice/Literature
Every meta-analysis that reviews influenza vaccine efficacy estimations has raised questions regarding existing information’s quality and inference. Bias within literature might be wholly or partly responsible for influenza vaccine success estimates. An evaluation of mortality risks from all cause and influenza/pneumonia-linked hospitalizations with regard to inoculation in time periods prior to, in the course of, and following influenza spells outcomes suggested preferential vaccine receipt by fairly healthier elderly individuals. Also, the bias wasn’t controlled for by the help of comorbid disease adjustments. Lastly, functional limits including need of bathing assistance link to lower immunization probability, even among elderly individuals without any comorbid issues (Lang et al. 2012).
Additional findings gleaned from a research revealed that following risk factor adjustment (age, self-reported wellbeing and health, and chronic problems) mortality prior to, in the course of, and following 9 seasons of influenza outbreak increased similarly with time among healthier persons as well as high-risk subgroups. All of the above findings offer sound evidence of the fact that selection-related bias constitutes a serious flaw among a large number of observational estimates among aged persons. The outcomes fail to offer valid evidence for estimating the actual advantages of influenza immunization programs.
Feasibility of Changing Practice
For differentiating between vaccine impacts and bias, an approach of “difference in differences” is put forward. That is, if the vaccine for influenza was actually capable of preventing mortality, large populations ought to exhibit obvious differences between the disparity in earlier immunization probability between survivors and decedents noted during influenza spells and the variance in earlier immunization probability between survivors and decedents anticipated on those very calendar dates when there is no influenza outbreak (Lang et al. 2012). According to Darvishian et al. it would require creation of a new bias-adjustment method that increases the assessors and puts in place empirical evidence (2014). Ideally, once potential biases are addressed, the vaccination is estimated to effectively prevent hospitalizations due to influenza among the elderly (Darvishian et al. 2014).
A more significant change will be observed when novel strategies exist for improving influenza vaccine efficacy estimate accuracy. Further research ought to encompass examination of weaknesses and strengths of multiple comparison intervals to validate the model, impact of key probable confounders, and alternate means (e.g., sensitivity analyses) of quantifying the effect of likely residual confounding. Complementarily, bias reduction approaches ought to encompass the acquisition of more correct and precise confounder data (including life expectancy and functional status), preventing all-cause mortality for results like influenza-linked or non-linked pneumonia and potential determination of influenza-specific results for improving research sensitivity for identifying true vaccine impact (Lang et al. 2012).
Barriers to Change: Perceived or Real
But precise additional mortalities to winter season mortalities ratio that may be ascribed to influenza proves hard to compute, on account of an absence of existing individual-level measures. The ratio employs a numerator underrating influenza-linked mortalities from a difficulty in realizing actual influenza burden; meanwhile, the denominator overvalues influenza season mortalities. Consequently, the ratio fails to correctly reflect influenza-linked absolute death burden, and hence, proves misleading in gauging influenza immunization death-rate benefit plausibleness. Hence, a “controversy” is raised out of questions pertaining to whether or not observational research bias and residual confounding have generated influenza vaccine efficacy estimates misjudging actual benefits. In the absence of intense change, present adjustment techniques will fail to appropriately control for biases; the aforementioned controversy will, thus, certainly persist (Lang et al. 2012).
Summary
Restatement of key findings
Trivalent inactivated vaccines for influenza are deemed to be efficient as well as economical. But despite extensive influenza inoculation drives, aged inpatients are increasingly seen in hospitals, for severe cardiovascular and respiratory issues, in the course of recent yearly national outbreaks of influenza. Growing influenza-related hospital admission and mortality rates in recent decades despite appreciable growth of influenza vaccine coverage in aged persons contrasts greatly with early inoculation benefits for this group. The study finds a lack of techniques capable of effectively tackling bias which interferes with influenza vaccine efficacy measurement accuracy (Lang et al. 2012).
Implications for Practice/Research
The study calls for an improved grasp of interference of vaccine response in age-linked change and their interface with commonly occurring chronic comorbid problems. Additionally, for validating future immunological therapy and influenza vaccines that increase protection among the elderly within head-to-head clinical trials, no reference point exists against which aging effects on influenza vaccine response may be predicted. Furthermore, although immunosenescence unquestionably interferes with immune system capacity when it comes to responding effectively to vaccination, individual responsiveness predictions by utilizing sound biological markers which differentiate between immunosenescent and healthy states is desirable as well (Lang et al. 2012).
References
Darvishian, M., Gefenaite, G., Turner, R. M., Pechlivanoglou, P., Van der Hoek, W., Van den Heuvel, E. R., & Hak, E. (2014). After adjusting for bias in meta-analysis seasonal influenza vaccine remains effective in community-dwelling elderly. Journal of clinical epidemiology, 67(7), 734-744.
Dawood, F. S., Prapasiri, P., Areerat, P., Ruayajin, A., Chittaganpitch, M., Muangchana, C.,… & Olsen, S. J. (2014). Effectiveness of the 2010 and 2011 Southern Hemisphere trivalent inactivated influenza vaccines against hospitalization with influenza-associated acute respiratory infection among Thai adults aged≥ 50 years. Influenza and other respiratory viruses, 8(4), 463-468.
Dominguez, A., Soldevila, N., Toledo, D., Godoy, P., Castilla, J., Force, L.,… & Martin, V. (2016). Factors Associated with Influenza Vaccination of Hospitalized Elderly Patients in Spain. Plos one, 11(1), e0147931.
Fry, A. M., Kim, I. K., Reed, C., Thompson, M., Chaves, S. S., Finelli, L., & Bresee, J. (2014). Modeling the effect of different vaccine effectiveness estimates on the number of vaccine-prevented influenza-associated hospitalizations in older adults. Clinical Infectious Diseases, 59(3), 406-409.
Goldstein, E., Greene, S. K., Olson, D. R., Hanage, W. P., & Lipsitch, M. (2015). Estimating the hospitalization burden associated with influenza and respiratory syncytial virus in New York City, 2003 — 2011. Influenza and other respiratory viruses, 9(5), 225-233.
Lang, P. O., Mendes, A., Socquet, J., Assir, N., Govind, S., & Aspinall, R. (2012). Effectiveness of influenza vaccine in aging and older adults: comprehensive analysis of the evidence.
Matias, G., Taylor, R. J., Haguinet, F., Schuck-Paim, C., Lustig, R. L., & Fleming, D. M. (2016). Modelling estimates of age-specific influenza-related hospitalization and mortality in the United Kingdom. BMC Public Health, 16(1), 1.
