Revaccination of high-risk adults with pneumococcal polysaccharide vaccine.
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Aged↗
Biomedical subjects
K L Nichol
Publications and source records attributed to K L Nichol.
Validation of self-report of influenza and pneumococcal vaccination status in elderly outpatients.
OBJECTIVE: To assess the validity of self-reported influenza and pneumococcal vaccination status. DESIGN: Cross-sectional surveys of outpatients aged 65 years or older. SETTING: A Veterans Affairs Medical Center (VA) and a community managed care organization (MCO). Both organizations have organized influenza and pneumococcal vaccination programs. SUBJECTS: VA subjects included all elderly respondents to a mailed survey of 500 randomly selected outpatients. MCO subjects included all respondents to a telephone survey of 300 randomly selected elderly members of the MCO. MEASUREMENTS: The VA survey was conducted following the 1995-1996 influenza season while the MCO survey was conducted following the 1994-1995 season. Self-report from the mailed survey for VA subjects and from the telephone survey for MCO subjects was compared to medical record documentation (paper and computerized combined). RESULTS: The response rate was 77% (n = 369) for the VA subjects of whom 195 (53%) were aged 65 or older. The response rate for the MCO subjects was 84% (n = 237). Self-report of influenza vaccination had a sensitivity (SENS) of 1.0 and a specificity (SPEC) of .79 with a kappa of .72 (95% CI .58-.86) among VA patients. Among MCO patients, self-report of influenza vaccination had a SENS of .98 and a SPEC of .71 with kappa of .75 (95% CI .69-.89). Self-report of pneumococcal vaccination status among VA patients had a SENS of .97 and a SPEC of .53 with a kappa of .42 (95% CI .32-.52). Among MCO patients, self-report of pneumococcal vaccination had a SENS of .90 and a SPEC of .64 with a kappa of .54 (95% CI .40-.68). A secondary analysis excluding subjects living outside of the VA's catchment area improved the specificity and indices of concordance of self-report of both influenza and pneumococcal vaccination. A secondary analysis of MCO data which excluded subjects who received a pneumococcal vaccination > 2 years prior to the study also improved concordance and the negative predictive value of self-report. CONCLUSIONS: Self-report of influenza vaccination is a highly sensitive and moderately specific measure. Self-report of pneumococcal vaccination is also a highly sensitive but less specific measure of vaccination status. Lower rates of validity for pneumococcal vaccination may reflect both less accurate recall, particularly for more distant vaccination, and less complete documentation in medical records.
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The health and economic benefits of influenza vaccination for healthy and at-risk persons aged 65 to 74 years.
OBJECTIVE: The objective of this study was to assess the health and economic benefits of influenza vaccination in both healthy and at-risk seniors aged 65 to 74 years. DESIGN AND SETTING: We used administrative claims data from 6 consecutive serial cohorts spanning the years 1990 to 1991 through 1995 to 1996. All members of a Twin-Cities managed care organisation who were > or = 65 years of age for the respective study year were included in each cohort. Other information obtained included demographic characteristics, baseline comorbidities, prior resource utilisation, and influenza vaccination status. Study outcomes included hospitalisations for pneumonia and influenza and for all respiratory conditions and death. Economic analyses assumed the societal perspective and included both direct and indirect costs. MAIN OUTCOME MEASURES AND RESULTS: During the 6 study seasons, there were 100 195 person-periods of observation for persons aged 65 to 74 years. Of these, two-thirds were healthy and one-third had at least one major baseline comorbidity. Influenza vaccination was associated with reductions in hospitalisations for pneumonia and influenza and for all respiratory conditions in both healthy and at-risk groups, although the results did not reach statistical significance among the healthy individuals. Vaccination was also associated with significant reductions in the risk of death for both groups. The economic analysis demonstrated that vaccination against influenza in the base case was associated with direct and total cost savings for both healthy and at-risk seniors aged 65 to 74 years. CONCLUSION: Influenza vaccination of healthy and at-risk seniors aged 65 to 74 years is associated with substantial health benefits and is cost saving. These findings support age-based vaccination strategies for all persons > or = 65 years of age.
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Influenza vaccination for healthy working adults.
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Adult↗
Benefits of influenza vaccination for low-, intermediate-, and high-risk senior citizens.
BACKGROUND: Vaccination rates for healthy senior citizens are lower than those for senior citizens with underlying medical conditions such as chronic heart or lung disease. Uncertainty about the benefits of influenza vaccination for healthy senior citizens may contribute to lower rates of utilization in this group. OBJECTIVE: To clarify the benefits of influenza vaccination among low-risk senior citizens while concurrently assessing the benefits for intermediate- and high-risk senior citizens. METHODS: All elderly members of a large health maintenance organization were included in each of 6 consecutive study cohorts. Subjects were grouped according to risk status: high risk (having heart or lung disease), intermediate risk (having diabetes, renal disease, stroke and/or dementia, or rheumatologic disease), and low risk. Outcomes were compared between vaccinated and unvaccinated subjects after controlling for baseline demographic and health characteristics. RESULTS: There were more than 20000 subjects in each of the 6 cohorts who provided 147551 person-periods of observation. The pooled vaccination rate was 60%. There were 101 619 person-periods of observation for low-risk subjects, 15 482 for intermediate-risk, and 30 450 for high-risk subjects. Vaccination over the 6 seasons was associated with an overall reduction of 39% for pneumonia hospitalizations (P<.001), a 32% decrease in hospitalizations for all respiratory conditions (P<.001), and a 27% decrease in hospitalizations for congestive heart failure (P<.001). Immunization was also associated with a 50% reduction in all-cause mortality (P<.001). Within the risk subgroups, vaccine effectiveness was 29%, 32%, and 49% for high-, intermediate-, and low-risk senior citizens for reducing hospitalizations for pneumonia and influenza (for high and low risk, P< or =.002; for intermediate risk, P = .11). Effectiveness was 19%, 39%, and 33% (for each, P< or =.008), respectively, for reducing hospitalizations for all respiratory conditions and 49%, 64%, and 55% for reducing deaths from all causes (for each, P<.001). Vaccination was also associated with direct medical care cost savings of $73 per individual vaccinated for all subjects combined (P = .002). Estimates of cost savings within each risk group suggest that vaccination would be cost saving for each subgroup (range of cost savings of $171 per individual vaccinated for high risk to $7 for low risk), although within the subgroups these findings did not reach statistical significance (for each, P> or =.05). CONCLUSIONS: This study confirms that healthy senior citizens as well as senior citizens with underlying medical conditions are at risk for the serious complications of influenza and benefit from vaccination. All individuals 65 years or older should be immunized with this vaccine.
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Effectiveness of pneumococcal vaccine.
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Ten-year durability and success of an organized program to increase influenza and pneumococcal vaccination rates among high-risk adults.
PURPOSE: Influenza and pneumococcal vaccines are underused. Systems approaches that incorporate administrative and organizational strategies are more successful than education of providers for improving vaccination rates. Little has been published on the long-term success and durability of such efforts. METHODS: We performed a 10-year time-series study to examine the durability and success of an ongoing, multifaceted, institution-wide influenza and pneumococcal vaccination program. The program was first implemented at the Minneapolis Department of Veterans Affairs (VA) Medical Center in 1987-88 following the demonstration that a clinic-based standing order policy was much more successful than provider education for improving vaccine delivery. The program ensures that vaccine is offered to all high-risk patients followed up at the medical center, promotes convenient access for patients, and facilitates efficient administration of vaccine. Specific elements include an annual mailing to patients, standing orders for nurses, walk-in clinics, and the use of standardized, preprinted documentation forms. Initially the program targeted high-risk outpatients for influenza vaccination. It was extended to include inpatients in 1989-90. Pneumococcal vaccinations were added to the program in 1994-95. Vaccination rates are estimated each year from surveys mailed to randomly selected patients, and vaccine utilization is monitored through pharmacy logs. RESULTS: The survey response rates have exceeded 75% each year. Influenza vaccination rates for all high-risk patients followed up at the medical center have increased from 58% following the 1987-88 vaccination season to 84% in 1996-97 (P < 0.001). Pneumococcal vaccination rates have also increased from 34% in 1994-95 to 63% in 1996-97 (P < 0.001). Vaccination rates are similar for inpatients and outpatients, but rates for high-risk patients < 65 years of age remain lower than for the elderly: 69% versus 89% for influenza, 1996-97 (P < 0.001); 52% versus 66% for pneumococcal, 1996-97 (P = 0.05). For elderly patients followed up at the medical center, influenza (89% versus 67%, P < 0.0001) and pneumococcal (66% versus 43%, P < 0.0001) vaccination rates significantly exceeded those for the state of Minnesota in 1996-97. The annual number of influenza vaccine doses dispensed has increased from 10,000 in 1987-88 to more than 22,000 in 1996-97; and more than 13,000 doses of pneumococcal vaccine have been administered from 1994-95 through 1996-97. CONCLUSION: This simple, multifaceted program that incorporates administrative and organizational strategies to enhance influenza and pneumococcal vaccination rates has been highly durable and successful over a 10-year peroid. Similar strategies if implemented in other settings may enhance vaccination rates for the millions of high-risk patients who have yet to be immunized.
Adult↗
Side effects associated with pneumococcal vaccination.
BACKGROUND: Pneumococcal disease is a major cause of morbidity and death, especially among elders and other people at high risk. In spite of long-standing national recommendations for its use, pneumococcal vaccine is underused, with 70% or more of targeted persons as yet unimmunized. Concern about side effects is a barrier to successful vaccine delivery. METHODS: Persons attending a walk-in pneumococcal vaccination clinic were surveyed by use of structured telephone interviews. They were asked about health characteristics and local and systemic symptoms experienced during the week after their vaccination (postvaccination period). These responses were compared with the symptoms they reported for the 7 days immediately preceding their interview (the comparison period). RESULTS: A total of 1006 persons were interviewed a mean of 65.4 days after their vaccination. They had an average age of 69.9 years, and approximately 95% were in a high-risk group targeted for pneumococcal vaccination. For all systemic symptoms including fever, rash, myalgias, fatigue, malaise, and headache, subjects reported similar or lower rates during the postvaccination week than during the comparison week. Local reactions occurred in 28.2% of subjects. These local symptoms were mild to moderate for more than 90% of subjects and rarely resulted in the need to decrease the use of their arm. CONCLUSION: Pneumococcal vaccination was not associated with an increase in systemic symptoms but was associated with mild to moderate local symptoms in about one fourth of vaccine recipients. These findings should help health care providers and their patients address an important barrier to pneumococcal immunization.
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Influenza vaccination of healthcare workers.
OBJECTIVE: To assess factors associated with influenza vaccination of healthcare workers. DESIGN: Cross-sectional survey. SETTING: University-affiliated Veterans' Affairs medical center. PARTICIPANTS: Staff physicians and nurses employed by the medical center. METHODS: A mailed, self-administered questionnaire. RESULTS: The response rate was 38.0%. The mean age of the respondents was 43.6 years, 71.5% were females, and 26.2% were physicians. Nearly all of the practitioners had daily or weekly contact with elderly or high-risk patients. The influenza vaccination rate of the respondents was 61.2%. More than 50% of vaccine recipients indicated that avoiding illness, protecting patients, and being able to receive the vaccine conveniently and free of charge all were very important factors influencing their decisions to receive the vaccine. Avoiding illness was rated the most important factor by 58.8% of vaccine recipients. Among vaccine nonrecipients, concern about side effects was identified as a very important factor by 36.2% and as the most important factor by 30.9%. Vaccine recipients were significantly more likely than were vaccine nonrecipients to indicate that influenza and its complications are very serious for high-risk patients. They also were more likely to report that the vaccine is very effective, that influenza vaccination is uncommonly associated with side effects, that healthcare workers' risk for contracting influenza is higher than the general public's risk, and that it is very important for healthcare workers to receive the vaccine to decrease risk for transmission to high-risk patients. After stepwise logistic regression, variables independently associated with receipt of vaccine were age, prior receipt of vaccine, being a physician, considering the vaccine to be very effective, believing that systemic side effects are uncommon, and indicating that it is very important for healthcare workers to receive vaccine for the protection of their patients. CONCLUSION: Many healthcare workers fail to receive influenza vaccine each year. Strategies to improve immunization levels should address concerns about vaccine safety and efficacy, barriers to vaccination including inconvenience and cost, and the reasons for targeting healthcare workers.
Adult↗
Booster doses of influenza vaccine.
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Adult↗
Side effects associated with influenza vaccination in healthy working adults. A randomized, placebo-controlled trial.
BACKGROUND: Concern about side effects is a barrier to influenza vaccination. This randomized, double-blind, placebo-controlled trial assessed side effects following vaccination among healthy working adults. METHODS: Healthy working adults were recruited during October and November 1994 and were randomized to receive influenza vaccine or placebo injections. Local and systemic symptoms during the week following the injection were evaluated through structured telephone interviews. RESULTS: Of 849 subjects enrolled in the study, 425 received a placebo and 424 received influenza vaccine. Baseline characteristics were similar between the groups, and 99% of subjects completed interviews to assess side effects after the study injection. No differences were seen between the 2 groups for the systemic symptoms of fever, myalgias, fatigue, malaise, or headaches. Overall, 35.2% of placebo and 34.1% of vaccine recipients reported at least 1 of these systemic symptoms (P = .78, chi 2). Vaccine recipients reported a higher rate of arm soreness at the injection site than did placebo recipients (63.8% vs 24.1%, P < .001). Local reactions were mild in both groups and infrequently resulted in decreased use of the arm. After logistic regression, female sex (odds ratio [OR], 1.5;95% confidence interval [CI], 1.1-2.1), age younger than 40 years (OR, 1.6;95% CI, 1.2-2.2), and coincidental upper respiratory tract illness (OR, 4.6; 95% CI, 3.2-6.6) were independently associated with higher rates of systemic symptoms. In the multivariate model, vaccine again was not associated with systemic symptoms (OR, 0.9; 95% CI, 0.7-1.2). CONCLUSIONS: Influenza vaccination of healthy working adults is not associated with higher rates of systemic symptoms when compared with placebo injection. These findings should be useful to physicians and other health care providers as they counsel patients to take advantage of an important opportunity for disease prevention and health protection.
Adult↗
Factors associated with influenza and pneumococcal vaccination behavior among high-risk adults.
OBJECTIVE: This cross-sectional survey assessed factors associated with influenza and pneumococcal vaccination behaviors among high-risk patients exposed to highly organized vaccination programs. INTERVENTIONS: Self-administered questionnaires were mailed to 700 patients randomly selected from the outpatient roster of the medical center. Questions were asked about patient demographic and health characteristics in addition to their knowledge and attitudes regarding influenza and pneumococcal diseases and vaccines. MAIN RESULTS: After three mailings, the response rate was 68%, and 80% of these respondents were in a high-risk ++group. Influenza and pneumococcal vaccination rates for high-risk respondents were 74.4% and 62.5%, respectively. Factors independently associated with both influenza and pneumococcal vaccination behaviors included health care providers' recommendations and having positive attitudes toward immunization. In addition, for influenza vaccination, willingness to comply with the provider's recommendation was also associated with receipt of the vaccine while cigarette smoking was associated with failure to receive the vaccine. CONCLUSIONS: Emphasis on provider recommendations and the knowledge and attitudes of patients may enhance influenza and pneumococcal vaccination rates, even in the context of organized vaccination programs.
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Immunizations in long-term care facilities: policies and practice.
PURPOSE: The present study was conducted to assess the policies and practices of nursing homes in regard to immunizations for residents and employees. METHODS: A 20-item, cross-sectional survey was mailed to all 445 Minnesota nursing homes from May through July 1993. Questions asked were about facility characteristics and their policies, practices, and attitudes regarding immunizations for residents and employees. Second and third mailings were sent to nonresponding institutions. RESULTS: The median size of 399 (90%) responding institutions was 88 beds and 110 employees. The median number of residents on December 1, 1992, was 84. Although 99% of the facilities had an influenza vaccination program, only 69.3% had written policies. The mean influenza vaccination rate for residents was 84%, with higher rates in institutions having written policies, facility-wide standing orders for vaccine administration, and in institutions that did not require written consent for vaccination. One-third of the facilities had written policies for pneumococcal vaccination, and 16.3% had policies for tetanus/diphtheria. Twelve-month immunization rates for these vaccines were 11.9% and 2.9%, respectively. Most facilities had an influenza vaccination program for employees with a mean vaccination rate of 33%. These rates were higher if the facility offered vaccine onsite, free of charge, and provided special inservice education to employees. Employee 12-month vaccination rates for hepatitis B and tetanus/diphtheria were 23.2% and 1.7%, respectively. Few of the institutions included evaluation of immunization activities in their quality assurance programs. CONCLUSION: Many long-term care facilities have inadequate policies and practices for ensuring their residents and employees immunity to important vaccine preventable diseases. These institutions, as caretakers for a vulnerable population, should develop and implement organized programs to immunize their residents and employees. By doing so, they will be able to take advantage of important opportunities to prevent illness and protect the health of their residents and employees.
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Effectiveness of influenza vaccine in the elderly.
OBJECTIVE: Each year, influenza and its complications account for 10,000-40,000 excess deaths in the United States. Over 80% of these deaths occur among the elderly. The Advisory Committee on Immunization Practices for the US Public Health Service and others recommend that all persons 65 years of age and older as well as other persons with high-risk conditions receive annual influenza vaccination. Despite these recommendations, 40% or more of high-risk persons fail to receive influenza vaccine. Among the barriers to successful immunization efforts are persistent uncertainties regarding the effectiveness of the vaccine in preventing morbidity and mortality associated with influenza. The purpose of this study was to assess influenza vaccine effectiveness in reducing hospitalization rates for a broad range of influenza-associated complications, in reducing deaths from all causes, and in reducing hospitalization costs among all elderly enrollees of a large health maintenance organization. METHODS: A serial cohort study with internal controls was designed. All enrollees, 65 years of age and older, were identified for each of three consecutive vaccination and subsequent influenza seasons for 1990-1991 through 1992-1993. Baseline characteristics and outcome data were collected from computerized, linked, administrative data bases. Outcomes were adjusted for the presence of baseline characteristics including age, gender, high-risk diagnoses, medication refills in high-risk therapeutic classes, and previous health care resource utilization. RESULTS: There were more than 25,000 seniors in each of the three study cohorts. Influenza vaccination rates ranged from 45 to 58%, and vaccinated subjects at baseline appeared to be 'sicker' than nonvaccinated subjects. Influenza vaccination was associated with significant reductions in all outcomes evaluated including outpatient visits (17% reduction in pneumonia and influenza visits, 6.4% reduction in all respiratory condition visits), hospitalizations (51.2% reduction in pneumonia and influenza hospitalizations, 32.5% reduction in all respiratory condition hospitalizations, 28.6% reduction in congestive heart failure hospitalizations), hospitalization costs (30.7% reduction in hospitalization costs for all respiratory conditions and congestive heart failure combined), and deaths from all causes (45% reduction in death from all causes). CONCLUSIONS: Influenza vaccination of elderly persons living in the community is associated with reduced hospitalizations from complications from influenza, with fewer deaths during the influenza season, and with direct health care cost savings. Few, if any, other preventive or therapeutic interventions for adults match or exceed these benefits.
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The effectiveness of vaccination against influenza in healthy, working adults.
BACKGROUND: Although influenza causes substantial morbidity and mortality in all age groups, current recommendations emphasize annual immunization for people at high risk for complications of influenza. We conducted a double-blind, placebo-controlled trial of vaccination against influenza in healthy, working adults. METHODS: In the fall of 1994, we recruited working adults from 18 to 64 years of age from in and around the Minneapolis-St. Paul area and randomly assigned them to receive either influenza vaccine or placebo injections. The primary study outcomes included upper respiratory illnesses, absenteeism from work because of upper respiratory illnesses, and visits to physicians' offices for upper respiratory illnesses. The economic benefits of vaccination were analyzed by estimating the direct and indirect costs associated with immunization and with upper respiratory illnesses. RESULTS: We enrolled a total of 849 subjects. Baseline characteristics were similar in the two groups. During the follow-up period, consisting of the 1994-1995 influenza season (December 1, 1994, through March 31, 1995), those who received the vaccine reported 25 percent fewer episodes of upper respiratory illness than those who received the placebo (105 vs. 140 episodes per 100 subjects, P < 0.001), 43 percent fewer days of sick leave from work due to upper respiratory illness (70 vs. 122 days per 100 subjects, P = 0.001), and 44 percent fewer visits to physicians' offices for upper respiratory illnesses (31 vs. 55 visits per 100 subjects, P = 0.004). The cost savings were estimated to be $46.85 per person vaccinated. CONCLUSIONS: Vaccination against influenza has substantial health-related and economic benefits for healthy, working adults.
Adolescent↗
Determinants of compliance with a national smoke-free hospital standard.
OBJECTIVE: To determine the extent of compliance with the new Joint Commission on Accreditation of Healthcare Organizations (JCAHO) standard requiring acute care hospitals to be smoke-free, and to identify predictors of adoption of smoke-free hospital policies. DESIGN: We conducted a survey of a national sample of acute care hospitals and developed a predictive model for implementation of smoke-free policies during multiple logistic regression. We examined numerous factors that might predict adoption of smoke-free policies, such as hospital characteristics, patient care services, and experience with smoke-free initiatives. SETTING AND PARTICIPANTS: A systematic 20% sample of JCAHO-accredited hospitals in the United States (n = 1278). Military, Department of Veterans Affairs, Indian Health Service, psychiatric, substance abuse treatment, and children's hospitals were excluded. MAIN OUTCOME MEASURE: Compliance with the JCAHO standard. RESULTS: The response rate was 85%. Six-five percent of hospitals were in compliance with the standard 16 months after it was introduced. Factors that were independently and positively associated with implementation of smoke-free policies were administrative support (odds ratio [OR], 7.82; 95% confidence interval [Cl], 2.05 to 29.65) and inpatient smoking cessation services (OR, 1.24; 95% Cl, 1.02 to 1.52). Factors negatively associated with implementation of smoke-free policy were the number of psychiatric treatment beds (OR, 0.57; 95% Cl, 0.14 to 0.81), number of substance abuse treatment beds (OR, 0.17; 95% Cl, 0.11 to 0.26), and presence of an active task force to address smoking policy (OR, 0.56; 95% Cl, 0.40 to 0.77). CONCLUSIONS: The majority of acute care hospitals are in compliance with the JCAHO national smoke-free policy initiative. The standard is well accepted by most patients and employees. It is critical to address the challenges presented by special populations, such as psychiatry patients, to accomplish the goal of completely smoke-free hospitals.
Accreditation↗
Women veterans' experiences with domestic violence and with sexual harassment while in the military.
BACKGROUND: Both domestic violence and sexual harassment may adversely affect women's health but often go unrecognized. OBJECTIVE: To assess women veterans' experiences with domestic violence and with sexual harassment while in the military as well as the relationship of such experiences to health and health care utilization. METHODS: We surveyed all 191 women hospitalized from March 1992 to 1993 at the Minneapolis (Minn) Veterans Affairs Medical Center and 411 randomly selected female outpatients. Data were collected using an anonymous validated questionnaire. RESULTS: Results were stratified by age and analyzed using both bivariable and multivariable techniques. Twenty-four percent of respondents under age 50 years reported domestic violence in the past year and 90% reported sexual harassment while in the military. Among older respondents, 7% said they had experienced domestic violence in the past year and 37% reported a history of sexual harassment while in the military. Of those who reported domestic violence in the past year, 50% of respondents under age 50 years and 28% of older respondents said that at least one assault was life-threatening. Rates of reports of completed and attempted sexual assaults while in the military were 20 times higher than previous reports by other government employees. Respondents with a history of either domestic violence (odds ratio, 2.83; 95% confidence interval [CI], 1.38 to 5.78) or sexual harassment while in the military (odds ratio, 2.84; 95% CI, 1.22 to 6.53) were more than twice as likely to report a history of anxiety or depression, and a history of domestic violence was associated with more lifetime surgical procedures (odds ratio, 1.21; 95% CI, 1.10 to 1.33). CONCLUSIONS: Histories of domestic violence within the past year and of sexual harassment while in the military are common among women veterans. Both may be associated with adverse effects on mental and physical health.
Adult↗
The efficacy and cost effectiveness of vaccination against influenza among elderly persons living in the community.
BACKGROUND: Despite recommendations for annual vaccination against influenza, more than half of elderly Americans do not receive this vaccine. In a serial cohort study, we assessed the efficacy and cost effectiveness of influenza vaccine administered to older persons living in the community. METHODS: Using administrative data bases, we studied men and women over 64 years of age who were enrolled in a large health maintenance organization in the Minneapolis-St. Paul area. We examined the rate of vaccination and the occurrence of influenza and its complications in each of three seasons: 1990-1991, 1991-1992, and 1992-1993. Outcomes were adjusted for age, sex, diagnoses indicating a high risk, use of medications, and previous use of health care services. RESULTS: Each cohort included more than 25,000 persons 65 years of age or older. Immunization rates ranged from 45 percent to 58 percent. Although the vaccine recipients had more coexisting illnesses at base line than those who did not receive the vaccine, during each influenza season vaccination was associated with a reduction in the rate of hospitalization for pneumonia and influenza (by 48 to 57 percent, P < or = 0.002) and for all acute and chronic respiratory conditions (by 27 to 39 percent, P < or = 0.01). Vaccination was also associated with a 37 percent reduction (P = 0.04) in the rate of hospitalization for congestive heart failure during the 1991-1992 season, when influenza A was epidemic. The costs of hospitalization for all types of illness studied were lower in the vaccinated group during 1991-1992 (range of reduction, 47 to 66 percent; P < 0.005) and for acute and chronic respiratory conditions and congestive heart failure in 1990-1991 (reductions of 37 percent and 43 percent, respectively; P < or = 0.05). Direct savings per year averaged $117 per person vaccinated (range, $21 to $235), with cumulative savings of nearly $5 million. Vaccination was also associated with reductions of 39 to 54 percent in mortality from all causes during the three influenza seasons (P < 0.001). CONCLUSIONS: For elderly citizens living in the community, vaccination against influenza is associated with reductions in the rate of hospitalization and in deaths from influenza and its complications, as compared with the rates in unvaccinated elderly persons, and vaccination produces direct dollar savings.
Acute Disease↗