Agreement between Internet-based self- and proxy-reported health care resource utilization and administrative health care claims.

OBJECTIVES: Although Internet-based surveys are becoming more common, little is known about agreement between administrative claims data and Internet-based survey self- and proxy-reported health care resource utilization (HCRU) data. This analysis evaluated the level of agreement between self- and proxy-reported HCRU data, as recorded through an Internet-based survey, and administrative claims-based HCRU data. METHODS: The Child and Household Influenza-Illness and Employee Function study collected self- and proxy-reported HCRU data monthly between November 2007 and May 2008. Data included the occurrence and number of visits to hospitals, emergency departments, urgent care centers, and outpatient offices for a respondent's and his or her household members' care. Administrative claims data from the MarketScan® Databases were assessed during the same time and evaluated relative to survey-based metrics. Only data for individuals with employer-sponsored health care coverage linkable to claims were included. The Kappa (κ) statistic was used to evaluate visit concordance, and the intraclass correlation coefficient was used to describe frequency consistency. RESULTS: Agreement for presence of a health care visit and the number of visits were similar for self- and proxy-reported HCRU data. There was moderate to substantial agreement related to health care visit occurrence between survey-based and claims-based HCRU data for inpatient, emergency department, and office visits (κ: 0.47-0.77). There was less agreement on health care visit frequencies, with intraclass correlation coefficient values ranging from 0.14 to 0.71. CONCLUSIONS: This study's agreement values suggest that Internet-based surveys are an effective method to collect self- and proxy-reported HCRU data. These results should increase confidence in the use of the Internet for evaluating disease burden.

Recent health-related quality of life, but not change, predicted mortality and healthcare utilization.

OBJECTIVE: To assess whether change in HRQOL over a seven-year period was associated with subsequent mortality and hospitalization, after adjusting for important covariates, in a cohort of U.S. Veterans. METHODS: We used data from a cohort of Veterans who completed a HRQOL survey in 1998 (Short-Form 36 for Veterans [SF-36V]) and a 2006 follow-up (SF-12V) HRQOL survey and SF12V scores were calculated at both time-points. We used logistic regression analyses to model the relationship between changes in the SF12-V physical component (PCS) and mental health component (MCS) scores and 1-year hospitalization and 1-year and 3.3-year mortality after the 2006 follow-up survey. RESULTS: 13,900 participants provided data for both the initial and follow-up surveys. We found no significant associations between changes in PCS or MCS and one-year hospitalization after adjusting for follow-up HRQOL and other covariates. We found significant but relatively weak associations between changes in MCS and our mortality outcomes. CONCLUSION: Given the follow-up MCS and PCS, change in PCS over the previous 7 years added little information for predicting mortality and hospitalization Although the change in MCS added some information for predicting mortality. Therefore, knowledge of patient's current HRQOL generally provides meaningful information for predicting subsequent mortality and hospitalization.

Effectiveness of influenza vaccine in the community-dwelling elderly.

BACKGROUND: Reliable estimates of the effectiveness of influenza vaccine among persons 65 years of age and older are important for informed vaccination policies and programs. Short-term studies may provide misleading pictures of long-term benefits, and residual confounding may have biased past results. This study examined the effectiveness of influenza vaccine in seniors over the long term while addressing potential bias and residual confounding in the results. METHODS: Data were pooled from 18 cohorts of community-dwelling elderly members of one U.S. health maintenance organization (HMO) for 1990-1991 through 1999-2000 and of two other HMOs for 1996-1997 through 1999-2000. Logistic regression was used to estimate the effectiveness of the vaccine for the prevention of hospitalization for pneumonia or influenza and death after adjustment for important covariates. Additional analyses explored for evidence of bias and the potential effect of residual confounding. RESULTS: There were 713,872 person-seasons of observation. Most high-risk medical conditions that were measured were more prevalent among vaccinated than among unvaccinated persons. Vaccination was associated with a 27% reduction in the risk of hospitalization for pneumonia or influenza (adjusted odds ratio, 0.73; 95% confidence interval [CI], 0.68 to 0.77) and a 48% reduction in the risk of death (adjusted odds ratio, 0.52; 95% CI, 0.50 to 0.55). Estimates were generally stable across age and risk subgroups. In the sensitivity analyses, we modeled the effect of a hypothetical unmeasured confounder that would have caused overestimation of vaccine effectiveness in the main analysis; vaccination was still associated with statistically significant--though lower--reductions in the risks of both hospitalization and death. CONCLUSIONS: During 10 seasons, influenza vaccination was associated with significant reductions in the risk of hospitalization for pneumonia or influenza and in the risk of death among community-dwelling elderly persons. Vaccine delivery to this high-priority group should be improved.

Burden of influenza-like illness and effectiveness of influenza vaccination among working adults aged 50-64 years.

BACKGROUND: Uncertainties regarding influenza disease impact and benefits of vaccination may contribute to low vaccination rates among adults aged 50-64 years. METHODS: This prospective cohort study assessed the burden of influenza-like illness (ILI) among working adults aged 50-64 years and the effectiveness of influenza vaccination in reducing the rate of ILI and productivity losses. Employees of the University of Minnesota (Minneapolis) were invited via e-mail to participate in the study during October 2006. The study data were collected using internet-based surveys at baseline (October 2006) and during the follow-up period (from November 2006 through April 2007). Months included in the 2006-2007 influenza season were identified retrospectively from Minnesota Department of Health surveillance data. Vaccine effectiveness for reducing the rate of ILI, ILI-associated health care use, the number of days of illness, work loss, and reduced on-the-job productivity during the influenza season were assessed using multivariable regression models after controlling for important confounders. RESULTS: Four hundred ninety-seven persons were included in the study, 85 (17.1%) of whom experienced an ILI. Among unvaccinated participants, ILI was responsible for 45% of all days of illness during the influenza season, 39% of all illness-related work days lost, and 49% of all days with illness-related reduced on-the-job productivity. In the multivariable regression analyses, vaccination was associated with a significant reduction in the rate of ILI (adjusted odds ratio, 0.48; 95% confidence interval, 0.27-0.86) and fewer days of illness, absenteeism, and impaired on-the-job performance. CONCLUSION: ILIs were common among our study participants, accounting for a large portion of illness, work loss, and impaired work performance during the influenza season. Vaccination was associated with substantial health and productivity benefits. Vaccine delivery should be improved for this high-priority group.

Rapid diagnosis of influenza infection in older adults: influence on clinical care in a routine clinical setting.

BACKGROUND: Laboratory diagnosis of influenza has previously relied on viral isolation in culture. Rapid antigen tests (RATs) are now available but few studies have examined their use in older adults under routine clinical conditions. OBJECTIVES: To determine the utility of the RAT in older adults presenting to a large medical center and how test results impacted clinical care. STUDY DESIGN: Retrospective chart review of patients tested for influenza during the 2003--2004 and 2004--2005 influenza seasons. Clinical data were correlated with the results of laboratory testing. RESULTS: Eighty-four adults tested positive for influenza. Adding the results of the RAT to symptom complexes predictive of influenza significantly enhanced the ability to diagnose influenza in the acute setting. The positive predictive value of fever plus cough increased from 32% to 92% with a positive RAT. The RAT also directed appropriate antiviral therapy. 20/22 (91%) patients with a positive RAT and symptoms < or =48 h received antiviral treatment compared to only 1/12 (8%) patients with a negative RAT and a positive culture. CONCLUSIONS: Under routine clinical conditions rapid influenza testing enhances the ability to quickly diagnose influenza and can be used to guide early treatment decisions in older adults.

Non-traditional settings for influenza vaccination of adults: costs and cost effectiveness.

OBJECTIVE: Influenza vaccination rates remain far below national goals in the US. Expanding influenza vaccination in non-traditional settings such as worksites and pharmacies may be a way to enhance vaccination coverage for adults, but scant data exist on the cost effectiveness of this strategy. The aims of this study were to (i) describe the costs of vaccination in non-traditional settings such as pharmacies and mass vaccination clinics; and (ii) evaluate the projected health benefits, costs and cost effectiveness of delivering influenza vaccination to adults of varying ages and risk groups in non-traditional settings compared with scheduled doctor's office visits. All analyses are from the US societal perspective. METHODS: We evaluated the costs of influenza vaccination in non-traditional settings via detailed telephone interviews with representatives of organizations that conduct mass vaccination clinics and pharmacies that use pharmacists to deliver vaccinations. Next, we constructed a decision tree to compare the projected health benefits and costs of influenza vaccination delivered via non-traditional settings or during scheduled doctor's office visits with no vaccination. The target population was stratified by age (18-49, 50-64 and >or=65 years) and risk status (high or low risk for influenza-related complications). Probabilities and costs (direct and opportunity) for uncomplicated influenza illness, outpatient visits, hospitalizations, deaths, vaccination and vaccine adverse events were derived from primary data and from published and unpublished sources. RESULTS: The mean cost (year 2004 values) of vaccination was lower in mass vaccination (dollars US 17.04) and pharmacy (dollars US 11.57) settings than in scheduled doctor's office visits (dollars US 28.67). Vaccination in non-traditional settings was projected to be cost saving for healthy adults aged >or=50 years, and for high-risk adults of all ages. For healthy adults aged 18-49 years, preventing an episode of influenza would cost dollars US 90 if vaccination were delivered via the pharmacy setting, dollars US 210 via the mass vaccination setting and dollars US 870 via a scheduled doctor's office visit. Results were sensitive to assumptions on the incidence of influenza illness, the costs of vaccination (including recipient time costs) and vaccine effectiveness. CONCLUSION: Using non-traditional settings to deliver routine influenza vaccination to adults is likely to be cost saving for healthy adults aged 50-64 years and relatively cost effective for healthy adults aged 18-49 years when preferences for averted morbidity are included.

Influenza vaccination and reduction in hospitalizations for cardiac disease and stroke among the elderly.

BACKGROUND: Upper respiratory tract illnesses have been associated with an increased risk of ischemic heart disease and stroke. During two influenza seasons, we assessed the influence of vaccination against influenza on the risk of hospitalization for heart disease and stroke, hospitalization for pneumonia and influenza, and death from all causes. METHODS: Cohorts of community-dwelling members of three large managed-care organizations who were at least 65 years old were studied during the 1998-1999 and 1999-2000 influenza seasons. Administrative and clinical data were used to evaluate outcomes, with multivariable logistic regression to control for base-line demographic and health characteristics of the subjects. RESULTS: There were 140,055 subjects in the 1998-1999 cohort and 146,328 in the 1999-2000 cohort, of which 55.5 percent and 59.7 percent, respectively, were immunized. At base line, vaccinated subjects were on average sicker, having higher rates of most coexisting conditions, outpatient care, and prior hospitalization for pneumonia than unvaccinated subjects. Unvaccinated subjects, however, were more likely to have been given a prior diagnosis of dementia or stroke. Vaccination against influenza was associated with a reduction in the risk of hospitalization for cardiac disease (reduction of 19 percent during both seasons [P<0.001]), cerebrovascular disease (reduction of 16 percent during the 1998-1999 season [P<0.018] and 23 percent during the 1999-2000 season [P<0.001]), and pneumonia or influenza (reduction of 32 percent during the 1998-1999 season [P<0.001] and 29 percent during the 1999-2000 season [P<0.001]) and a reduction in the risk of death from all causes (reduction of 48 percent during the 1998-1999 season [P<0.001] and 50 percent during the 1999-2000 season [P<0.001]). In analyses according to age, the presence or absence of major medical conditions at base line, and study site, the findings were consistent across all subgroups. CONCLUSIONS: In the elderly, vaccination against influenza is associated with reductions in the risk of hospitalization for heart disease, cerebrovascular disease, and pneumonia or influenza as well as the risk of death from all causes during influenza seasons. These findings highlight the benefits of vaccination and support efforts to increase the rates of vaccination among the elderly.

Clinical effectiveness of first and repeat influenza vaccination in adult and elderly diabetic patients.

OBJECTIVE: Influenza vaccine uptake remains low among the high-risk group of patients with diabetes, partly because of conflicting evidence regarding its potential benefits. We assessed the clinical effectiveness of influenza vaccination in adults with diabetes and specifically examined potential modification of effect by age and prior influenza vaccine uptake. RESEARCH DESIGN AND METHODS: The study was part of the Prevention of Influenza, Surveillance and Management (PRISMA) study, a nested case-control study conducted during the 1999-2000 influenza A epidemic, among 75,235 patients from primary care of any age recommended for vaccination. Among 9,238 adult patients with diabetes, 131 cases arose who were either hospitalized for diabetes dysregulation, acute respiratory disease, or cardiovascular disease and 61 cases who died, and we compared them with 1,561 control subjects. We evaluated the effect of (prior) influenza vaccination by means of logistic regression analysis controlling for age, sex, health insurance coverage, prior health care use, medication use, and comorbid conditions. RESULTS: Vaccination was associated with a 56% reduction in any complication (95% CI 36-70%), a 54% reduction in hospitalizations (26-71%), and 58% reduction in deaths (13-80%). Among study subjects aged 18-64 years, we observed somewhat higher reductions in the occurrence of any complication than among those aged >65 years (72 vs. 39%). In first-time vaccinated subjects, the primary end point was reduced by 47% (0.2-72%), and in those who received vaccination in the year before, the reduction was 58% (4-81%). CONCLUSIONS: Adults with type 2 diabetes, like other individuals from recognized risk groups, benefit considerably from influenza vaccination, and no difference in vaccine effectiveness was observed between first-time and repeat vaccination.

Comparison of Side Effects of the 2015-2016 High-Dose, Inactivated, Trivalent Influenza Vaccine and Standard Dose, Inactivated, Trivalent Influenza Vaccine in Adults ≥65 Years.

BACKGROUND: High-dose, inactivated, trivalent influenza vaccine (HD) is associated with higher rates of side effects than standard dose (SD) vaccine, which may represent a barrier to use. METHODS: We surveyed subjects ≥65 years who received either HD or SD vaccine at the Minneapolis Veteran Affairs Health Care System clinics on October 27, 28, or 29, 2015. Research assistants conducted a 17-item telephone survey of influenza vaccine recipients to inquire about self-reported health and symptoms experienced the week after vaccination. RESULTS: A total of 547 HD recipients and 541 SD recipients responded to the survey. The 2 groups were similar at baseline with respect to age, gender, and presence of high-risk medical conditions. At least ≥95% of individuals in both HD and SD groups reported that their overall health was the same or better than usual during the week after vaccination. Thirty-seven percent of HD recipients and 22% of SD recipients reported a local or systemic side effect (P < .001), most of which were mild to moderate. Only 7 of 547 (1.3%) HD recipients and 3 of 541 (0.6%) SD recipients reported a severe side effect (P = .34). There was no significant difference in healthcare visits between the groups. CONCLUSIONS: Side effects were more common among subjects ≥65 years who received HD influenza vaccine compared with SD vaccine. These side effects were well tolerated and were not associated with impairment of general health status. These findings should reassure patients and their providers of the safety and tolerability of the HD influenza vaccine.

Impact of a winter respiratory virus season on patients with COPD and association with influenza vaccination.

BACKGROUND: We assessed the effects of an influenza season on patients with COPD. Data from 2,215 veterans in a multicenter, randomized, double-blind influenza vaccine efficacy study were analyzed for changes in spirometric and functional status, comparing patients with laboratory-documented influenza (LDI)-caused illness, non-LDI-caused respiratory illness, or no illness, and for association with influenza vaccination. METHODS: Patients received either IM trivalent inactivated influenza virus vaccine (TIV) plus intranasal trivalent, live attenuated, cold-adapted influenza virus vaccine (TC) or TIV plus intranasal placebo (TP). We performed spirometry, measured the chronic lung disease severity index (CLDSI) score to assess functional status and well-being, and tested for influenza virus infection. RESULTS: Worsening in FEV(1), percentage of predicted FEV(1), and CLDSI score (p < 0.001) was associated with acute respiratory illness in 585 illnesses including 94 LDI-caused illnesses. LDI-caused illness was more likely to be associated with worsening in FEV(1) and CLDSI score acutely than non-LDI-caused illness (p < 0.01). Logistic regression showed acute respiratory illness (odds ratio [OR], 1.78; 95% confidence limit [CL], 1.40 to 2.26) to be associated with worsening in CLDSI score, and receipt of TC (OR, 1.39; 95% CL, 1.10 to 1.74) and no illness (OR, 0.70; 95% CL, 0.53 to 0.91 for acute respiratory illness) to be associated with better CLDSI score at the end of the study. Hospitalization was more frequent in patients with acute respiratory illness (p < 0.0001). CONCLUSIONS: Acute respiratory illness was associated with increased health-care utilization and obstruction to airflow, and worse functional status and well-being. At the end of the study, receipt of TC was associated with improvement and acute respiratory illness was associated with worsening in functional status and well-being.

Improving influenza vaccination rates among adults.

Influenza remains an important cause of illness and death in this country. Even though we have safe and effective vaccines, vaccination rates among the elderly and other high-risk groups remain static and well below national goals. Health care providers can boost these vaccination rates by educating themselves, by recommending that their patients be vaccinated, and by implementing evidence-based strategies such as programs to remind themselves and patients to be vaccinated, to utilize standing orders for nurses or other qualified professionals to offer and administer vaccines, and to provide feedback on performance. We should also consider alternative paradigms for vaccine delivery, and be sure to be vaccinated ourselves.

Colds and influenza-like illnesses in university students: impact on health, academic and work performance, and health care use.

BACKGROUND: Upper respiratory tract illnesses (URIs) are a major cause of morbidity among adults, with substantial direct and indirect costs to society, but their impact among university students has not been well described. We sought to assess the impact of URIs (colds and influenza-like illnesses [ILIs]) on the health, academic and work performance, and health care use of university students. METHODS: This was a cohort study of college students at the University of Minnesota, Twin Cities campus (Minneapolis-St. Paul), who were recruited during October 2002 and followed up from November 2002 through April 2003. All 42,000 registered students were invited via e-mail to participate. Baseline information was obtained in October 2002. Monthly follow-up information about colds or ILIs was obtained for the period of November 2002 through April 2003. Data were collected by use of Internet-based questionnaires. RESULTS: Of 4919 volunteers, 3249 completed all follow-up surveys. The mean age was 22.7 years; 68% of the volunteers were female. Ninety-one percent had > or = 1 URI (83% had > or = 1 cold, and 36.7% had > or = 1 ILI). These URIs caused 6023 bed-days, 4263 missed school days, 3175 missed work days, and 45,219 days of illness. Of the cohort, 22.2% had > or = 1 health care visit, and 15.8% used antibiotics to treat a URI; 27.8% did poorly on a test and 46.3% did poorly on a class assignment. ILIs versus colds had a much greater impact on all parameters (e.g., general health level was 55%-60% lower with ILI vs. no URI and 33%-39% lower for colds vs. no URI; P < .001 for each). CONCLUSION: Colds and ILIs were common and associated with substantial morbidity in university students. Enhanced efforts to prevent and control URIs, especially influenza vaccination, could improve the health and well-being of the 17 million college and university students in this country.

Health-related quality of life predicts future health care utilization and mortality in veterans with self-reported physician-diagnosed arthritis: the veterans arthritis quality of life study.

OBJECTIVE: To investigate whether health-related quality of life (HRQOL) measures predict health care utilization and mortality in a cohort of veterans with self-reported physician-diagnosed arthritis. METHODS: A cohort of veterans from the Upper Midwest Veterans Integrated Service Network (VISN) was mailed a self-administered questionnaire that was composed of the SF-36V (modified from SF-36 for use in veterans) and questions regarding demographics, current smoking status, limitation of activities of daily living (ADLs), and preexisting physician-diagnosed medical conditions, including arthritis. Within subjects reporting physician-diagnosed arthritis, we analyzed the associations between the SF-36V component summary scales (physical and mental component summary, PCS and MCS, respectively) and the occurrence of any hospitalization, number of hospitalizations, number of outpatient visits, and mortality, for the year after survey administration, using multivariable regression analyses. RESULTS: Of 34,440 survey responders who answered a question regarding arthritis, 18,464 (58%) subjects reported physician-diagnosed arthritis. Arthritic patients in the lowest tertile of PCS scores had significantly higher odds of any hospitalization (Odds ratio (OR) 1.49, 95% confidence interval (CI) [1.25-1.76]) and mortality (OR 1.69, 95% CI [1.18-2.42]), and a significantly higher number of hospitalizations/year (Rate ratio (RR) 1.09, 95% CI [1.05-1.13]) and outpatient visits/year (RR 1.07, 95% CI [1.03-1.11]). Arthritic patients in the lowest tertile of MCS scores had significantly higher odds of any hospitalization (OR 1.20, 95% CI [1.02-1.41]), mortality (OR 2.14, 95% CI [1.56-2.94]), and a significantly higher number of hospitalizations/year (RR 1.05, 95% CI [1.02-1.09]) and outpatient visits/year (RR 1.07, 95% CI [1.03-1.11]). CONCLUSIONS: HRQOL, as assessed by the SF-36V, predicts future inpatient and outpatient health care utilization and mortality in veterans with self-report of physician-diagnosed arthritis.

Health-related quality of life, functional impairment, and healthcare utilization by veterans: veterans' quality of life study.

OBJECTIVES: To describe the health status of veterans receiving care in a veterans integrated service network (VISN). DESIGN: Cross-sectional survey with prospective follow-up. SETTING: Former Upper Midwest VISN 13 (now a part of VISN 23), a regional Veterans Affairs (VA) network comprising five inpatient facilities and associated outpatient clinics. PARTICIPANTS: All veterans in VISN 13 who had at least one inpatient or outpatient encounter between October 1, 1997, and March 31, 1998. MEASUREMENTS: Health-related quality of life (HRQOL) assessed using subscales and component summaries from the 36-item short form for veterans (SF36-V), functional status assessed according to limitations in activities of daily living (ADLs), healthcare utilization assessed according to outpatient visits and hospitalizations, and death. RESULTS: Of 70,334 eligible veterans, 40,508 responded and reported baseline HRQOL significantly lower than that of the general U.S. population for the physical (35.6, P<.001) and mental (46.4, P<.001) component summary scores (PCS and MCS, respectively) of the SF36-V. Many reported complete inability or some difficulty in completing ADLs such as getting in and out of a chair (35.1%) and walking (45.3%). More than 58% indicated some degree of difficulty with at least one of the ADLs. In multivariate analysis, PCS and MCS were significantly associated with subsequent use of inpatient and outpatient care and with mortality. CONCLUSION: The low quality of life and associated high rates of health services utilization in VA patients imply a need for innovative strategies to improve the HRQOL and functional status of this population.

Where adults reported receiving influenza vaccination in the United States.

BACKGROUND: Influenza vaccination coverage remains unacceptably low among persons aged > or =65 years and younger high-risk adults. This study assessed locations at which US adults receive influenza (flu) vaccinations and the relative roles that traditional and nontraditional vaccination settings play in influenza vaccine delivery. METHODS: We analyzed data on types of settings at which last flu shot was received, reported by adult respondents to the 1999 Behavioral Risk Factor Surveillance System, stratified by age group and medical condition. We used multivariable logistic regression to identify factors associated with nontraditional vaccination settings. RESULTS: In 1998-1999, reported influenza vaccination coverage was 19% for persons aged 18-49 years, 36% for persons aged 50-64 years, and 67% for persons aged > or =65 years. Seventy percent of flu shots received by persons aged > or =18 years were reportedly administered in doctors' offices and other traditional settings. Vaccination in nontraditional settings (eg, workplace, stores, community centers) was more likely for young, healthy, employed, white, college-educated adults who had not had a recent routine checkup. CONCLUSION: Physicians should offer vaccination services at every opportunity. Increasing access to vaccination services in nontraditional settings should be considered as another strategy in pursuit of national vaccination coverage objectives.

Influenza vaccination in the elderly: impact on hospitalisation and mortality.

Influenza causes substantial morbidity across the age spectrum. However, the elderly are especially vulnerable to the serious complications of influenza that might result in hospitalisation or death, and high rates of influenza-associated excess hospitalisation or death that exceed by several-fold the rates seen among most other age groups have consistently been observed in many countries and across many seasons. Thus, the elderly are included among the high priority groups for routine influenza vaccination by many national health authorities. Inactivated influenza virus vaccines are widely available across the globe and are safe and effective. Vaccination of elderly persons has been associated with significant reductions in hospitalisations for pneumonia and influenza as well as hospitalisations for other cardiopulmonary disorders and even cerebrovascular disease. Vaccination has also been associated with reductions in influenza-associated and all-cause mortality during influenza seasons. The benefits of vaccination extend not only to community-dwelling elderly but also to elderly who reside in nursing homes. Likewise, vaccination provides benefits to the very old and to elderly persons with underlying co-morbidities as well as to the healthy elderly. Despite the substantially increased risk for serious complications and impressive benefits from vaccination among the elderly, influenza vaccine utilisation remains below target rates for this group in nearly all countries. The need for improved prevention and control of influenza is recognised as a priority for the global community--both to reduce the morbidity and mortality associated with epidemic influenza and to prepare for the next pandemic. Enhancing vaccine delivery to elderly persons would represent important progress toward that goal.

Recognizing influenza in older patients with chronic obstructive pulmonary disease who have received influenza vaccine.

A substudy analysis was conducted to determine the clinical characteristics associated with symptomatic, laboratory-documented influenza (LDI) among 2215 veterans with chronic obstructive pulmonary disease who participated in Department of Veterans Affairs Cooperative Study 448 and who received trivalent inactivated influenza virus vaccine with or without intranasal live-attenuated, cold-adapted influenza vaccine. Of 585 evaluable first occurrences of acute respiratory illnesses, 94 (16%) were LDI. Respiratory symptoms of cough, sputum production, and dyspnea occurred in >90% of patients with LDI; 68% had documented or subjective fever, and 81% had myalgias. Stepwise logistic regression identified only fever and myalgia as being statistically associated with LDI. During the influenza outbreak period, the positive predictive value of fever and myalgia was 41%. Clinical criteria were poor predictors of LDI in these older, vaccinated patients with chronic lung disease. Additional studies are warranted to define optimal methods for the diagnosis of influenza among older persons with chronic obstructive pulmonary disease.

Influence of high-risk medical conditions on the effectiveness of influenza vaccination among elderly members of 3 large managed-care organizations.

This serial cohort study assessed the risk of hospitalization or death associated with influenza and the effectiveness of influenza vaccination among subgroups of elderly members of 3 managed-care organizations in the United States. Data on baseline characteristics and outcomes were obtained from computerized databases. A total of 122,974 (1996-1997 season) and 158,454 (1997-1998 season) persons were included in the cohorts. Among unvaccinated persons, hospitalizations for pneumonia/influenza or death occurred in 8.2 of 1000 healthy and 38.4 of 1000 high-risk persons in year 1, and in 8.2 of 1000 healthy and 29.3 of 1000 high-risk persons in year 2. After adjustments, vaccination was associated with a 48% reduction in the incidence of hospitalization or death (95% confidence interval [CI], 42-52) in year 1 and 31% (95% CI, 26-37) in year 2. Effectiveness estimates were statistically significant and generally consistent across the healthy and high-risk subgroups. The absolute risk reduction, however, was 2.4- to 4.7-fold higher among high-risk than among healthy elderly persons. All elderly individuals may substantially benefit from vaccination. However, the impact of influenza is greater in persons with high-risk medical conditions.

Safety, efficacy, and effectiveness of live, attenuated, cold-adapted influenza vaccine in an indicated population aged 5-49 years.

BACKGROUND: Three important studies have supported licensure of live, attenuated, cold-adapted influenza vaccine (CAIV-T [FluMist; MedImmune Vaccines]): (1) a pediatric efficacy trial involving children 15-71 months of age, (2) a large safety study of medically attended events occurring among children 1-17 years of age, and (3) an effectiveness trial involving healthy working adults 18-64 years of age. METHODS: During the United States Food and Drug Administration (FDA) review for the approval of CAIV-T for use in healthy persons, additional subgroup analyses were conducted to evaluate the safety, efficacy, and effectiveness of the vaccine, by use of various age subsets not prespecified by the original protocols. CAIV-T is currently approved by the FDA for use in healthy persons 5-49 years of age. In this article, we present data from some of the aforementioned subanalyses. RESULTS: The efficacy of CAIV-T in children >or=5 years of age (age range of the children in year 1 of the study, 60-71 months; age range of the children in year 2 of the study, 60-83 months) was similar to that reported for the entire cohort in year 1 (90.6%; 95% confidence interval [CI], 70.3%-97.1%). In year 2 of the study, efficacy was 86.9% (95% CI, 70.8%-94.1%), despite the presence of antigenically drifted influenza type A/Sydney/5/97 (H3N2), which caused most illnesses that occurred in year 2. Safety outcomes for children 5-17 years of age revealed no significant difference between vaccine recipients and placebo recipients, with regard to acute respiratory events, acute gastrointestinal events, systemic bacterial infection, or rare events possibly related to influenza. Effectiveness among adults 18-49 years of age was similar to that reported for the entire cohort--for example, for occurrence of severe febrile illness, there was a 19.5% reduction (P=.02) in adults. CONCLUSIONS: The present reanalysis summarizes data on the indicated uses for CAIV-T in the indicated population aged 5-49 years.