close

Вход

Забыли?

вход по аккаунту

?

0003-4819-121-12-199412150-00008

код для вставкиСкачать
ACADEMIA
AND
CLINIC
Influenza Vaccination Programs for Elderly Persons:
Cost-effectiveness in a Health Maintenance Organization
John P. Mullooly, PhD; Marjorie D. Bennett, MRP; Mark C. Hornbrook, PhD; William H. Barker, MD;
Walter W. Williams, MD; Peter A. Patriarca, MD; and Phillip H. Rhodes, PhD
• Objective: To estimate the cost-effectiveness and
net medical care costs of programs for annual influenza
vaccinations for the elderly in a health maintenance
organization (HMO).
• Design: Population-based, case-control study.
• Setting: The Northwest Region of Kaiser Permanente, a prepaid group practice HMO in Portland,
Oregon.
• Participants: Kaiser Permanente members 65 years
of age and older who had at least 1 month of HMO
eligibility during any of nine influenza seasons in the
1980s.
• Measurements: The HMO's costs for providing medical care and conducting vaccination programs were
estimated using accounting data.
• Results: 32% of high-risk elderly persons and 22%
of non-high-risk elderly persons received influenza
vaccinations. Aggregate vaccine effectiveness in preventing pneumonia and influenza hospitalizations was
30% (95% CI, 17% to 42%) for high-risk and 40% (CI,
1 % to 64%) for non-high-risk elderly persons. The net
savings to the HMO per vaccination was $6.11 for
high-risk elderly persons and $1.10 for all elderly persons. The HMO incurred a net cost of $4.82 per vaccination for non-high-risk elderly persons.
• Conclusions: Influenza vaccination rates in this HMO
were relatively low for high-risk elderly persons. The
medical care costs saved by preventing pneumonia
and influenza through vaccination of high-risk elderly
persons provide a compelling rationale to increase
compliance with recommendations for annual influenza
vaccination. Indirect benefits, such as prevention of
suffering, incapacity, and lost wages, are likely to compensate for the small net cost of vaccinating non-highrisk elderly persons.
Ann Intern Med. 1994;121:947-952.
From Kaiser Permanente Center for Health Research, Portland,
Oregon; University of Rochester, Rochester, New York; and the
Centers for Disease Control and Prevention, Atlanta, Georgia.
For current author addresses, see end of text.
A n n u a l influenza vaccination of elderly and chronically
ill persons has been a long-standing recommendation of
the U.S. Public Health Service (1, 2). Recent studies have
documented the health benefits of annual influenza vaccination (3-10), but despite the exhortations of the Surgeon General and the clear evidence of vaccine efficacy,
many persons in high-risk groups fail to receive the recommended vaccinations (11, 12). Because of the low level
of compliance with the U.S. Public Health Service influenza vaccination guidelines (13), the Centers for Disease
Control and Prevention (CDC) have proposed new strategies to increase the proportion of high-risk persons who
are immunized (14). One such strategy is to promote
assessments of the net financial costs to health maintenance organizations of operational vaccine delivery programs. Successful demonstrations of net financial benefit
should encourage managers of organized medical care
programs and health insurance companies to advocate
improved vaccine delivery.
Methods
General Methods
Setting
The study was done at Kaiser Permanente, Northwest Region,
a prepaid group practice health maintenance organization
(HMO) that includes 20% of the Portland, Oregon-Vancouver,
Washington, Standard Metropolitan Statistic Area population.
Members receive almost all of their medical care from the health
plan, and each contact they make with the HMO is recorded in
a single, centralized chart.
Epidemic Periods
Epidemic periods were defined as periods during which influenza viruses circulated persistently in Oregon according to influenza virus isolation dates reported by the Oregon State Virology
Laboratory. The eight epidemic periods defined using this approach are shown in Table 1. The study period for the nonepidemic 1981-1982 reference period was defined by averaging the
months and days of the epidemic periods. The number of specimens tested ranged from 118 in 1981-1982 to 652 in 1988-1989.
Influenza viruses were isolated from only 9 of 118 specimens
(8%) tested in the 1981-1982 nonepidemic reference period; B
viruses were isolated from two specimens obtained in late April.
During the epidemic study periods, influenza viruses were typically isolated from 25% of specimens, isolations were sustained,
and isolation frequency distributions described epidemic curves.
Participants
Participants included in a study period were Kaiser Permanente members 65 years of age or older, each with at least 1
month of eligibility during that period and during the September-December vaccination period. These members represent almost all elderly persons enrolled in the HMO.
High-risk participants were defined as those who had had
medical care contacts for chronic pulmonary (ICDA [International Classification of Diseases, Adapted] codes 9:491-493.9, 496,
500-505, 506.4, 508.1, 510-516, 714.8), cardiovascular (112.81, 130.3,
© 1994 American College of Physicians
Downloaded From: https://annals.org/ by a Queens Univ Belfast User on 10/25/2017
947
Table 1. Influenza Epidemic Periods and Study Samples
Epidemic
Period
1
2
3
4
5
6
7
8
Nonepidemic
Total personperiods
Isolation Dates*
(Earliest-Latest)
12/10/80
11/26/82
12/29/83
01/02/84
01/03/85
10/29/86
12/22/87
11/23/88
12/17/81
to
to
to
to
to
to
to
to
to
03/20/81
01/06/83
03/27/84
02/27/85
03/10/86
01/28/87
03/31/88
03/31/89
03/10/82t
Duration, Elderly Study
wk
Participants, n
16
6
14
9
10
14
16
19
12
21009
23 330
24 604
25 664
28 922
32 434
35 363
37 587
22121
251 034
* Periods of sustained isolation of influenza virus reported by Oregon
State Department Virology Laboratory.
t Average of epidemic periods.
393-398, 401.0, 402-405, 410-414, 416, 420-429, 430-438, 440.1,
785.2-.3), metabolic (250-250.9, 571-571.9), renal (274.10, 580583.9, 585, 587-588.0), or malignant (140-208.9) conditions. These
risk factors for influenza-related complications are defined by the
CDC's Advisory Committee for Immunization Practices.
Data Sources
An automated inpatient database was used to identify all hospitalizations for pneumonia and influenza during the nine study
periods. This database contains discharge diagnoses and records
of inpatient procedures and is the source of the discharge summaries.
The outpatient database contains outpatient diagnoses and
records of procedures for a continuously updated research sample composed of 5% of elderly health plan members. Each
month, a random 5% sample of all new elderly Kaiser Permanente subscriber units is added to the cumulative pool of enrollees whose records are abstracted. Automated outpatient diagnoses were available through 1987. Medical record abstractions
were the source of outpatient diagnoses for the first quarter of
1988.
Inpatient high-risk discharge diagnoses made during the 3
years before the study period were obtained from the inpatient
database. Outpatient high-risk diagnoses made during the year
before the study period were obtained from the outpatient database and by chart abstraction.
Influenza and pneumococcal vaccination status was abstracted
from the medical records for pneumonia and influenza cases that
were not in the 5% research sample. Automated vaccination data
through 1987 were available for cases and controls in the research sample. Medical record abstractions were the source of
1988-1989 vaccination data for all study participants. Participants
receiving influenza vaccine after the start of epidemics were
classified as unvaccinated.
Case-Control Assessment of Vaccine Effectiveness
Population-based, case-control designs were used to estimate
influenza vaccine effectiveness in preventing medically attended
episodes of pneumonia and influenza. To exclude pneumonias
that were unlikely to be influenza related, we included only
persons with pneumonia and influenza who were admitted to
medical services. Because we based participant selection on discharge diagnoses, participants with both hospital- and community-acquired pneumonia and influenza were included.
Pneumonia and Influenza Cases and Controls
Participants who were hospitalized with pneumonia and influenza during the study period, who were eligible Kaiser Permanente members, and who had a pneumonia and influenza
ICDA-9 code (480-483, 485-486, 487) listed as a discharge diagnosis were included as cases of hospitalized pneumonia and
influenza. Controls were members of the 5% research sample
who met the study eligibility criteria and who were not hospitalized with pneumonia or influenza during the given period.
Pneumonia and influenza deaths during a study period were
948
defined as hospitalized patients with pneumonia and influenza
who died in the hospital. Controls were members of the 5%
research sample who were not pneumonia and influenza hospital
deaths during that period.
Outpatient pneumonia and influenza cases included members
of the 5% research sample who had an outpatient episode of
pneumonia and influenza with no inpatient component during
the given study period. Controls were members of the 5% research sample who did not have an outpatient episode of pneumonia and influenza during the given period.
Cases and controls were group matched for high-risk status.
Logistic regressions were used to adjust influenza vaccine effects
on occurrence of pneumonia and influenza episodes for differences in age, sex, months of HMO eligibility, and pneumococcal
vaccine status.
Vaccine Effectiveness
Relative risks for pneumonia and influenza episodes in unvaccinated and vaccinated populations were estimated by the adjusted exposure (unvaccinated) odds ratios. The effectiveness of
influenza vaccine in preventing pneumonia and influenza episodes was computed from the estimated relative risk as effectiveness = l-(l/relative risk).
Pneumonia and Influenza Episodes Prevented
The population-based, case-control design allowed unbiased
estimation of the total number of participants vaccinated and of
the pneumonia and influenza episode rates among unvaccinated
participants. The product of these estimates multiplied by the
vaccine effectiveness is the estimated number of pneumonia and
influenza episodes prevented by influenza vaccination: pneumonia and influenza episodes prevented = (number of participants
vaccinated)(effectiveness of vaccination)(pneumonia and influenza episode rate among unvaccinated participants).
Statistical Methods
The units of analysis for period-specific vaccine effectiveness
analyses were persons. A case for a given period had an episode
of pneumonia or influenza during that period. A control for a
given period did not have an episode of pneumonia or influenza
during that period. The same person could appear as a case in
more than one period.
Person-periods were the units of analysis for aggregate analyses. A person contributed a person-period of observation to each
period when study criteria were met. Some members of the 5%
research sample were controls in some periods and cases in other
periods. Study participants not in the 5% research sample could
only contribute person-periods as hospitalized cases.
Risks for pneumonia and influenza episodes during high-risk
and non-high-risk person-periods are separately modeled as logistic functions of influenza vaccine status, pneumococcal vaccine
status, age, sex, and length of observation time.
The SAS logistic procedure was used to estimate odds ratios
and confidence intervals for model variables. The Hosmer-Lemeshow statistic was used to assess the goodness of fit of logistic
models.
Cost Analysis Methods
Medical Care Costs of Pneumonia and Influenza Episodes
Costs of providing inpatient care for pneumonia and influenza
episodes were obtained from Kaiser Permanente accounting systems for the various patient care cost centers. Costs of providing
outpatient care were estimated from the 5% research sample,
using relative value units included in the outpatient database and
unit costs for accounting cost centers.
Cost of Vaccine Delivery
Costs of the vaccine delivery program were estimated by a
micro-costing approach and included overhead costs. The purchase cost of vaccine was obtained from administrative records
and included all vaccines used and wastage. Distribution costs
were allocated based on the proportion of direct drug costs
represented by influenza vaccine.
Two methods of promoting the vaccination program were
identified: an article in the member newsletter and referrals by
15 December 1994 • Annals of Internal Medicine • Volume 121 • Number 12
Downloaded From: https://annals.org/ by a Queens Univ Belfast User on 10/25/2017
Table 2. Excess Pneumonia and Influenza Hospitalization Rates per 10 000 per 12 Weeks
Epidemic
Period
Virus
1980-1981
1981-1982
H3N2
Nonepidemic
++++
61.2 ± 8.1
39.9 ± 6.8
1982-1983
1983-1984
H3N2
B
H,N,
H3N2
B
H,N,
H3N2
B
H t N,
++++
+
80.9 ± 12.8
+
+
65.4 ± 7.4
78.7 ± 9.9
63.3 ± 7.8
48.3 ± 5.3
59.3 ± 5.3
25.5 ±
38.8 ±
23.4 ±
8.4 ±
19.4 ±
++++
++++
59.2 ± 4.3
19.3 ± 8.0t
1984-1985
1985-1986
1986-1987
1987-1988
1988-1989
Match between
Epidemic and Predominant
Vaccine Strains*
++
+
++
High-•Risk Persons
Rate
Non-High-Risk Persons
Excess Rate
Rate
Excess Rate
21.3 ± 10.6t
Non-epidemic
reference period
41.0 ± 14.5t
4.4 ± 1.6
3.8 ± 1.7
0.6 ± 2.3
Non-epidemic
reference period
9.8 ± 4.9t
10.0t
12.0t
10.3t
8.6
8.6t
13.6 ± 4.6
13.1 ±
15.8 ±
9.9 ±
4.0 ±
3.7 ±
2.9
3.9
2.7
1.4
1.2
9.8 ± 2.0
9.3 ±
12.0 ±
6.1 ±
0.2 ±
-0.1 ±
3.4t
4.2t
3.2
2.2
2.1
6.0 ± 2.6t
* Personal communication from Centers for Disease Control Influenza Virus Reference Laboratory. + + + + = identical or minimal difference; + + +
= high cross-reaction; + + = moderate cross-reaction; + = some cross-reaction. Multiple ratings are given for co-circulating viruses. Rates are expressed
± SE.
t/ > <0.05.
nurses, generally by the telephone advice nurse. Time estimates
were obtained from interviews with providers, and labor costs per
hour were obtained from Kaiser Permanente administrative
records.
Cost-effectiveness Ratios
Three cost-effectiveness measures were computed: cost per
prevented episode of outpatient pneumonia and influenza, cost
per prevented episode of hospitalization, and cost per prevented
hospital death.
Net Financial Benefit
Only direct monetary costs and benefits to the HMO were
considered. The formula, treating costs as negative benefits, is as
follows: net benefits = (number of hospitalizations prevented)
(mean cost per hospitalization) + (outpatient contacts prevented) (mean cost per outpatient contact) - (number of vaccinations) (unit cost of vaccine and supplies + unit cost of vaccine
wastage + unit cost of vaccine promotion + unit cost of vaccine
delivery + unit cost of overhead) - (number of adverse reactions to vaccine)(mean cost of treating adverse reactions).
Results
Over the nine study periods, 58% of person-periods
were contributed by women, 37% were contributed by
persons older than 74 years of age, and 40% were contributed by persons at high risk for complications of influenza. The influenza and pneumococcal vaccination
rates for high-risk elderly persons were 32% and 16%,
respectively. For non- high-risk person-periods, the vaccination rates were 22% for influenza and 7% for pneumococcal infection. Vaccinations done after the start of epidemics accounted for 6% of total vaccinations.
There were 765 hospitalizations due to pneumonia and
influenza in 734 persons, and 106 in-hospital deaths due
to pneumonia and influenza occurred among high-risk
elderly persons during the nine study periods. Among
non-high-risk elderly persons, there were 129 hospitalizations in 128 persons and 7 in-hospital deaths. Sixty-six
outpatient episodes among 62 high-risk persons and 47
outpatient episodes among 47 non-high-risk persons were
identified in the 5% research sample during the 1980-81
to 1987-88 study periods.
The aggregate analyses of hospitalizations, deaths, and
outpatient episodes among high-risk elderly persons in-
cluded 1474, 1476, and 1250 controls, respectively. The
corresponding numbers of controls included in the aggregate analyses for non-high-risk elderly persons were 2291,
2292, and 1612, respectively. Controls in both risk strata
contributed person-periods of observation to an average
of 3.3 study periods.
Chronic pulmonary and cardiovascular conditions were
the major high-risk conditions; these accounted for 87%
and 82%, respectively, of high-risk conditions among
high-risk cases and controls. The direction of this small
difference would be expected to result in a slight underestimation of vaccine effectiveness. No direct medical care
attributable to adverse reactions to influenza vaccine was
detected in the 5% research sample during the nine periods. Table 2 shows excess pneumonia and influenza
hospitalization rates for the influenza epidemic periods
relative to the 1981-1982 nonepidemic reference period.
The high-risk populations experienced significant excesses
during all epidemic periods except 1986-1987. Significant
excesses occurred in the non-high-risk populations only
during 1982-1983, 1983-1984, 1984-1985, and 1988-1989.
Table 3 presents the fitted logistic regression models
for pneumonia and influenza episodes when the data
from all nine study periods were pooled. Nonuse of influenza vaccine was associated with increased risk for
pneumonia and influenza hospitalization. Age was associated with increased risk for all types of pneumonia and
influenza episodes. Male sex was associated with an increased risk for hospitalization due to episodes of pneumonia and influenza among high-risk elderly persons and
with increased risk for outpatient episodes of pneumonia
and influenza episodes among non-high-risk elderly persons. Among high-risk elderly persons, use of pneumococcal
vaccine was associated with increased risk for episodes of
pneumonia and influenza requiring hospitalization. Highrisk elderly persons were more likely to have received
pneumococcal vaccine. Controlling this proxy for level of
risk slightly increased the estimated effectiveness of influenza vaccination. All the logistic models fit the data well,
except for the outpatient pneumonia and influenza model
for non-high-risk elderly persons, which was estimated
from only 47 episodes.
15 December 1994 • Annals of Internal Medicine • Volume 121 • Number 12
Downloaded From: https://annals.org/ by a Queens Univ Belfast User on 10/25/2017
949
Table 3. Logistic Regression Models for Episodes of Pneumonia and Influenza among High-Risk and Non-High-Risk
Elderly Persons
Group
No Influenza Vaccine
P Value
Odds Ratio (CI)
Pneumococcal Vaccine
P Value
Odds Ratio (CI)
High-risk persons
(GOF = 6.33, P = 0.611)
Hospitalized death
(GOF = 7.56, P = 0.481)
Outpatient
(GOF = 7.18, P = 0.518)
Non-high-risk persons
Hospitalizations
(GOF = 3.78, P = 0.872)
Outpatient
(GOF = 15.42, P = 0.052)
1.44 (1.20 to 1.73)
0.000
1.55 (1.27 to 1.89)
0.000
1.49 (0.94 to 2.38)
0.093
1.36 (0.81 to 2.27)
0.248
1.41 (0.79 to 2.51)
0.242
1.78 (0.95 to 3.34)
0.074
1.68 (1.01 to 2.79)
0.045
1.15 (0.61 to 2.14)
0.669
1.75 (0.72 to 4.24)
0.215
1.50 (0.44 to 5.07)
0.517
* GOF = goodness of fit.
prevented 83 inpatient and 194 outpatient episodes, saving $496 154. When this savings is compared with the cost
of the vaccination program, a net savings of $6.11 (CI,
-$0.23 to $11.53) per vaccination was achieved. Cumulated over the 9 seasons, the non-high-risk vaccination
program prevented 12 inpatient and 135 outpatient episodes, saving $72 759. This savings was less than the cost
of the vaccination program and resulted in a net cost of
$4.82 (CI, $3.34 to $7.06) per vaccination. For all elderly
persons, the HMO saved $1.10 in direct medical care
costs per vaccination (CI,-$3.36 to $4.71).
Although influenza vaccines were 40% (CI, 1% to
64%) effective in preventing inpatient episodes among
non-high-risk elderly persons, the low hospitalization rate
in this population did not result in enough prevented
episodes to produce net savings. The finding that influenza vaccination programs were cost saving for the elderly
is sensitive to the vaccine effectiveness estimates. For
high-risk elderly persons, the upper confidence estimate
of net cost per vaccination is only $0.23, and the HMO
recovered 97% of the $7.11 cost per vaccination. For
non-high-risk elderly persons, essentially none of the
HMO's costs were recovered. Optimistically, for high-risk
elderly persons, the HMO saves $11.53 per vaccination
and incurs a net cost of $3.34 per vaccination for nonhigh-risk elderly persons. There is an overall savings of
$4.71 per vaccination.
Vaccine Effectiveness
Influenza vaccination was 30% (CI, 17% to 42%) effective in preventing hospitalizations due to pneumonia
and influenza among high-risk elderly persons when the
data from all nine study periods were pooled. The aggregate effectiveness of influenza vaccines in preventing inhospital death due to pneumonia and influenza among
high-risk elderly persons was 33% (CI, - 7 % to 58%),
not significantly different from zero. Aggregated influenza vaccine effectiveness in preventing hospitalizations
for pneumonia and influenza among non-high-risk elderly persons was 40% (CI, 1% to 64%). Influenza vaccines were 83% (CI, 54% to 94%), 70% (CI, 9% to 90%),
and 5 1 % (CI, 13% to 73%) effective in preventing hospitalizations for pneumonia and influenza among high-risk
elderly persons during the 1980-1981, 1982-1983, and
1986-1987 epidemics, respectively. Effectiveness estimates
for the other five epidemic periods ranged from 15% to
32% and were not statistically significant. The effectiveness estimates are generally consistent with the levels of
cross-reaction between epidemic and vaccine strains during these epidemics (Table 2).
Cost Analysis
The total medical care costs for pneumonia and influenza were $45.50 and $5.14 per person-period for highrisk and non-high-risk elderly persons, respectively. Overall, the total medical care cost for pneumonia and
influenza was $21.27 per person-period (Appendix Table
The estimated cost of delivering a vaccination during
the nine seasons was $7.11, of which $2.76 was for overhead, $2.35 for delivery of the injection, $1.45 for vaccine
and supplies, $0.29 for promotion, and $0.26 for wastage.
Aggregated over the nine periods, the estimated cost
per hospitalization prevented among high-risk elderly persons was $3234 (Table 4). The aggregate cost per hospitalization prevented in non-high-risk elderly persons was
$18 817.
For the nine seasons, the high-risk vaccination program
950
Discussion
We show that, in the long term, a program of annual
influenza vaccination is cost-effective and cost-saving or
cost-neutral for high-risk elderly persons. Indirect benefits
such as prevention of suffering, incapacity, and lost wages
are likely to compensate for the small net cost of vaccinating non-high-risk elderly persons. Because our costeffectiveness and net financial benefit results are based on
HMO costs rather than charges, they cannot be directly
generalized to the fee-for-service sector in which most
elderly persons receive their medical care. However, we
would expect equally effective vaccination programs in the
15 December 1994 • Annals of Internal Medicine • Volume 121 • Number 12
Downloaded From: https://annals.org/ by a Queens Univ Belfast User on 10/25/2017
Table 3—Continued
Length of Observation
Odds Ratio per Month (CI)
Age
Odds Ratio per Decade (CI)
P Value
2.46 (2.21 to 2.74)
0.000
1.76 (1.49 to 2.06)
0.000
1.54 (1.39 to 1.70)
0.000
2.99 (2.30 to 3.89)
0.000
2.31 (1.54 to 3.46)
0.000
0.67 (0.53 to 0.86)
0.001
2.04 (1.46 to 2.84)
0.000
1.51 (0.92 to 2.49)
0.101
1.03 (0.71 to 1.49)
0.887
3.20 (2.59 to 3.94)
0.000
0.97 (0.67 to 1.42)
0.882
1.00 (0.82 to 1.21)
0.968
1.72 (1.15 to 2.55)
0.008
1.82 (1.02 to 3.26)
0.042
1.14 (0.98 to 2.28)
0.065
Male Sex
Odds Ratio (CI)
fee-for-service sector to have achieved even greater net
financial benefits because fee-for-service hospital admission rates and lengths of stay were higher than in HMOs
during the 1980s. Although vaccination program costs are
expected to be lower in HMOs, we would speculate that
the HMO-fee-for-service differential in vaccination program costs would not entirely compensate for the differential in medical care costs. On the basis of the 19881992 Medicare Influenza Vaccine Demonstration, the
Health Care Financing Administration applied various
cost, vaccine coverage, and vaccine effectiveness estimates
and concluded that influenza vaccine was cost-effective for
Medicare and was possibly cost-saving, depending on the
effectiveness of the vaccine and the level of vaccine coverage (15).
Our estimate of $1.10 cost savings (in 1985 dollars) per
vaccination over the nine study periods is considerably
smaller than the U.S. Congressional Office of Technology
Assessment estimate of $4.00 cost savings (in 1978 dollars) per vaccination (16, 17). Their simulation study was
based on Kaiser Permanente's records during the 1968-1969
and 1972-1973 epidemics, when both vaccine effectiveness
P Value
and excess pneumonia and influenza hospitalization rates
were higher (18, 19). Our study results provide a basis for
formulating influenza vaccination policies and financing
annual vaccination programs in HMOs and other managed care organizations. Substantial additional medical
care cost-saving would be expected to accrue to the study
HMO if the influenza vaccination rate among high-risk
elderly were increased from the 32% rate achieved in the
1980s. The ultimate cost benefit to such organizations
depends, of course, on their ability to overcome organizational, provider, and, most of all, member barriers to
vaccination programs. Consequently, further research is
needed to fully understand the nature of these barriers
and the likely success of various educational programs in
overcoming them (20-22). Our study shows, however,
that managed care organizations have a financial incentive
to institute influenza vaccination programs for their elderly members.
Appendix Table 1. Costs of Influenza Vaccination Programs and Medical Care for Pneumonia and Influenza
among High-Risk and Non-High -Risk Elderly Persons
1980-1981-1988-1989*
Table 4. Pneumonia and Influenza Morbidity and Mortality Prevented by Influenza Vaccination: Cost-effectiveness Ratios among High-Risk and Non-High-Risk Elderly Persons, 1980-1981-1988-1989*
Variable
Outpatient episodes
prevented, «f
Cost per outpatient
episode prevented, $
Hospitalizations
prevented, n
Cost per hospitalization
prevented, $
Inhospital deaths
prevented, n
Cost per in-hospital
death prevented, $
High-Risk
Elderly
Persons
Non-HighRisk Elderly
Persons
All Elderly
Persons
194
135
329
1375
1673
1497
83
12
95
3234
18 817
5213
13
2
15
21347
150 539
35 189
P Value
* Costs in 1985 U.S. dollars.
t Estimated from 5% sa mple, 1980-1981-1986-1987.
High-Risk
Elderly
Persons
Person-periods, n
Vaccinations, n
Total cost of vaccination
programs, $
Cost per vaccination, $
Cost of vaccination
programs per member
per month, $
Medical care costs per
outpatient episode, $
Medical care costs per
inpatient episode, $
Outpatient costs per
person-period, $
Inpatient costs per
person-period, $
Total costs per
person-period, $
Non-High- All Elderly
Risk Elderly
Persons
Persons
100 321
37 517
150 713
31748
251 034
69 264
266 842
7.11
225 809
7.11
492 651
7.11
0.19
0.13
0.15
106
141
122
5730
4477
5559
1.80
1.31
1.51
43.69
3.83
19.76
45.50
5.14
21.27
* Costs in 1985 U.S. dollar*
15 December 1994 • Annals of Internal Medicine • Volume 121 • Number 12
Downloaded From: https://annals.org/ by a Queens Univ Belfast User on 10/25/2017
951
Grant Support: In part by the Centers for Disease Control Contract
200-89-0748.
Requests for Reprints: John P. MuUooly, PhD, Kaiser Permanente Center
for Health Research, 3800 North Kaiser Center Drive, Portland, OR
97227-1098.
9.
Current Author Addresses: Drs. MuUooly and Hornbrook and Ms. Bennett:
Kaiser Permanente Center for Health Research, 3800 North Kaiser Center
Drive, Portland, OR 97227.
Dr. Barker: University of Rochester, Department of Community and Preventive Services, 601 Elmwood Avenue, Rochester, NY 14642.
Drs. Williams, Patriarca, and Rhodes: Centers for Disease Control and
Prevention, Division of Immunization, 1600 Clifton Road, Atlanta, GA 30305.
10.
11.
References
1. Sencer DJ, Rubin RJ. Risk as the Basis for Immunization Policy in the
United States. In: Perkins FT, Regamey RH, eds. Proceedings of the
International Symposium on Influenza Vaccines for Men and Horses.
New York: Karger; 1973;20:244-51.
2. Healthy People 2000: National Health Promotion and Disease Prevention Objectives. Washington, D.C.: U.S. Department of Health and
Human Services, Public Health Service; 1991:76.
3. Patriarca PA, Weber JA, Parker RA, Hall WN, Kendal AP, Bregman
DJ, et al. Efficacy of influenza vaccine in nursing homes. Reduction in
illness and complications during an influenza A (H3N2) epidemic.
JAMA. 1985;253:1136-9.
4. Patriarca PA, Weber JA, Parker RA, Orenstein WA, Hall WN, Kendal
AP, et al. Risk factors for outbreaks of influenza in nursing homes. A
case-control study. Am J Epidemiol. 1986;124:114-9.
5. Barker WH, MuUooly JP. Influenza vaccination of elderly persons.
Reductions in pneumonia and influenza hospitalizations and deaths.
JAMA. 1980;244:2547-9.
6. Barker WH, MuUooly JP. Effectiveness of inactivated influenza vaccine among non-institutionalized elderly persons. In: Kendal AP, Patriarca PA, eds. Options for the Control of Influenza: Proceedings of
a Viratek-UCLA Symposium, held in Keystone, Colorado, April 2 0 25, 1985. New York: Liss; 1986;169-82.
7. Foster DA, Talsma A, Furumoto-Dawson A, Ohmit SE, Margulies JR,
Arden NH, et al. Influenza vaccine effectiveness in preventing hospitalization for pneumonia in the elderly. Am J Epidemiol. 1992;136:
296-307.
8. Monto AS, Ohmit SE, Foster DA, et al. Case-control study in Michigan on prevention of hospitalization by vaccination, 1989-1991. In:
952
15 D e c e m b e r 1994 • Annals
of Internal Medicine
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
Hannoun C, ed. Options for the Control of Influenza II: Proceedings
of the International Conference on Options for the Control of Influenza, Courchevel, 27 September-2 October, 1992. Amsterdam, New
York: Excerpta Medica; 1993:135-41.
Barker W, Raubertas R, Menegus M, O'Brien D, Freundlich C, Betts
R. Case control study of influenza vaccine effectiveness in preventing
pneumonia hospitalization among older persons, Monroe County, NY,
1989-92. In: Hannoun C, ed. Options for the Control of Influenza II:
Proceedings of the International Conference on Options for the Control of Influenza, Courchevel, 27 September-2 October, 1992. Amsterdam: Excerpta Medica; 1993:143-51.
Fedson DS, Wajda A, Nicol JP, Hammond GW, Kaiser DL, Roos LL.
Clinical effectiveness of influenza vaccination in Manitoba. JAMA.
1993;270:1956-61.
Williams WW, Hickson MA, Kane MA, Kendal AP, Spika JS, Hinman
AR. Immunization policies and vaccine coverage among adults. The
risk for missed opportunities. Ann Intern Med. 1988;108:616-25.
Influenza vaccination levels in selected states-Behavioral Risk Factor
Surveillance System, 1987. MMWR Morb Mortal Wkly Rep. 1989;38:
124-33.
Implementation of recommendations for influenza control. MMWR
Morb Mortal Wkly Rep. 1985;34:639-43.
Prevention and Control of Influenza. Recommendations of the Immunization Practices Advisory Committee (ACIP). Prevention and Control of Influenza. MMWR Morb Mortal Wkly Rep. 1989;38:297-311.
Centers for Disease Control and Prevention. Final results: Medicare
influenza vaccine demonstration-selected states, 1988-1992. MMWR
Morb Mortal Wkly Rep. 1993;42:601-04.
Cost Effectiveness of Influenza Vaccination. Washington, D.C.: Congress of the U.S., Office of Technology Assessment; 1981.
Riddiough MA, Sisk JE, Bell JC. Influenza vaccination. JAMA. 1983;
249:3189-95.
Barker WH, MuUooly JP. Impact of epidemic type A influenza in a
defined adult population. Am J Epidemiol. 1980;112:798-813.
MuUooly JP, Barker WH. Impact of type A influenza on children: a
retrospective study. Am J Public Health. 1982;72:1008-16.
MuUooly JP. Increasing influenza vaccination among high-risk elderly:
a randomized controlled trial of a mail cue in an HMO setting. Am J
Public Health. 1987;77:626-7.
Barton MB, Schoenbaum SC. Improving influenza vaccination performance in an HMO setting: the use of computer-generated reminders
and peer comparison feedback. Am J Public Health. 1990;80:534-6.
Schoenbaum SC. Implementation of preventive services in an HMO
practice. J Gen Intern Med. 1990;5(Suppl):S123-7.
• V o l u m e 121 • N u m b e r 12
Downloaded From: https://annals.org/ by a Queens Univ Belfast User on 10/25/2017
Документ
Категория
Без категории
Просмотров
4
Размер файла
1 043 Кб
Теги
4819, 121, 0003, 199412150, 00008
1/--страниц
Пожаловаться на содержимое документа