health outcomes group, palo alto, cahealthoutcomesgroup.com/asthma_econ.pdf · •days limited 0.2...
TRANSCRIPT
David U. Himmelberger
Health Outcomes Group, Palo Alto, CA
ISOQoL, Amsterdam, 6 November 2001
Evaluate the relationship between:
- asthma severity (GINA)
and
- resource consumption
Study Methods
• National survey of asthmatics
• Consecutive patients
• Physical evaluation of asthmatic status
• Patient self-report of resource consumption
- limitation of activities – past 14 days
- medication use and MD visits – past 6 months
- hospitalization and lost work – past year
• Intermittent – symptoms < 1 time a week
• Mild Persistent – sym > 1 time a week and
sym < 1 time a day
• Moderate Persistent – symptoms daily
• Severe Persistent – symptoms continuously
GINA Classification Using 7 Variables
• Daytime Symptoms
• Nocturnal Symptoms
• Attacks
• Use of beta-agonists
• Physical Activity
• FEV1
• PEF Variability
Total: 300 pts
North 125 pts
Center 225 pts
South 150 pts
Total: 500 pts
Demographics
Italy Spain
• Age 38.0 38.0 yrs
• Gender (male %) 42.8 28.3 %
• Married / Living together 59.8 62.3 %
• Education (primary or less) 12.4 50.0 %
• Employed 66.4 49.7 %
Asthma Related Conditions
Italy Spain
• Rhinitis 56.8 51.0 %
• Sinusitis 21.2 13.7 %
• Atopic Dermatitis 3.8 6.0 %
• Chronic Uticaria 2.4 3.7 %
• Nasal Polyps 13.0 8.0 %
• Family History of Above 40.2 34.7 %
Italy Spain
• Intermittent 34.8 43.7 %
• Mild Persistent 26.8 28.3 %
• Moderate Persistent 30.6 23.0 %
• Severe Persistent 7.8 3.7 %
Not Reported 0.0 1.3 %
Italy Spain
• Intermittent 27.2 29.0 %
• Mild Persistent 29.8 43.0 %
• Moderate Persistent 37.6 22.7 %
• Severe Persistent 5.4 3.0 %
Not Reported 0.0 2.3 %
GINA Classification
Asthma Severity – Past Year
Actual vs. Predicted Pulmonary Function - Morning
0
1
2
3
4
5
6
7
Intermittent Mild Moderate Severe
Asthma Severity During the Past Year
Pe
ak
F
low
Actual
Predicted
Morning Peak Flow - Italy
Actual vs. Predicted Pulmonary Function - Evening
0
1
2
3
4
5
6
7
Intermittent Mild Moderate Severe
Asthma Severity During the Past Year
Pe
ak F
low
Actual
Predicted
Evening Peak Flow - Italy
• Past 14 days
• daytime symptoms
• nocturnal symptoms
• symptom free days
• asthma medication use
• limitation of activities
• effects of attacks
Resource Consumption
• Past year
• days missed from paid work
• days missed from unpaid work
• effectiveness at paid work
• visits to emergency room
• hospitalization
• Past 6 months
• physician visits
• use of asthma medications
• oral steroid use
0
1
2
3
4
5
6
Intermittent Mild Moderate Severe
Asthma Severity
Da
ys
-du
rin
g p
as
t 1
4 d
ay
s
Past 14 Days
Past Year
Days Limited by Asthma - Spain
0
1
2
3
4
5
6
7
8
9
Intermittent Mild Moderate Severe
Asthma Severity
Da
ys
-du
rin
g p
as
t 14
da
ys
Past 14 Days
Past Year
Days Limited by Asthma - Italy
Effect of Asthma for Patients with Intermittent vs Severe Asthma
Italy Spain
• Nights Awake 0.2 / 7.2 0.5 / 3.4
• Days with Symptoms 1.1 / 9.3 1.5 / 8.4
• Days Limited 0.2 / 8.2 0.3 / 5.2
(During the past 14 days)
Lost Days of Paid Work - Italy
0
5
10
15
20
25
Intermittent Mild Moderate Severe
Asthma Severity
Da
ys
Lo
st
Past 14 Days
Past Year
Lost Days of Unpaid Work - Italy
0
1
2
3
4
5
6
7
8
9
Intermittent Mild Moderate Severe
Asthma Severity
Da
ys
Lo
st
Past 14 Days
Past Year
0
10
20
30
40
50
60
70
80
90
100
Intermittent Mild Moderate Severe
Asthma Severity
De
gre
e o
f E
ffe
cti
ve
ne
ss
Past 14 Days
Past Year
Low
Normal
Effectiveness at Paid Work – Italy (during past 14 days)
0
10
20
30
40
50
60
70
80
90
100
Intermittent Mild Moderate Severe
Asthma Severity During the Past 14 Days
Pe
rce
nta
ge
of
Pa
tie
nts
wit
h A
tta
ck o
f
Giv
en
S
eve
rit
y
Severe Effect
Moderate Effect
Slight Effect
Short Effect
No Attacks
Effects of Asthma Attacks – Italy (during past 14 days)
Physician Visits Intermittent vs Severe Asthma
Italy Spain
• Non specialists 1.9 / 7.9 1.8 / 6.2
• Pulmonologists 1.2 / 2.5 0.4 / 2.0
• Allergologist 1.4 / 2.3 0.3 / 2.0
(During the past 6 months)
0
2
4
6
8
10
12
14
16
18
Intermittent Mild Moderate Severe
Asthma Severity
Inh
ale
rs p
er
6 m
on
ths
Past 14 Days
Past Year
Consumption of All Inhaled Medications – Spain
0
2
4
6
8
Intermittent Mild Moderate Severe
Asthma Severity
Inh
ale
rs p
er
6 m
on
ths
Past 14 Days
Past Year
Consumption of All Inhaled Medications – Italy
0
2
4
6
8
Intermittent Mild Moderate Severe
Asthma Severity
Pre
scri
ptio
ns p
er
6 m
on
ths Past 14 Days
Past Year
Consumption of All Oral Medications – Italy
Non-planned Visits and Procedures Intermittent vs Severe Asthma
Italy Spain
• Hospitalization Rate 0.05 / 1.12 0.03 / 0.22
• Days Hospitalized 0.4 / 10.2 4.3 / 3.0
• Visits to Emergency 0.1 / 1.7 1.1 / 2.7
• Courses of Oral Steroids 0.4 / 2.2 0.3 / 1.7
(During the past year)
0
50000
100000
150000
200000
250000
300000
350000
400000
450000
500000
Intermittent Mild Moderate Severe
Asthma Severity During the Past Year
Pe
se
tas
Medication
Physician Visits
Hospital Visits
Work Lost
Average Cost per Patient per Year – Spain
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Intermittent Mild Moderate Severe
Asthma Severity During the Past Year
Pe
rce
nta
ge
of
To
tal C
os
t
Medication
Physician Visits
Hospital Visits
Work Lost
Distribution of Cost – Spain
Limitations
Possible selection bias in participants
Self reported data
Small representation of severe asthma
Better measures of pulmonary function
Better economic data
More major medical problems
Peak flow 10% lower than predicted
Use of inhalers 2.5 times higher
Days with symptoms 3 times higher
Nights awake 3 times higher
Days limited 3 – 5 times higher
Asthma attacks 3 times higher
More frequent hospitalization
Longer length of stay
Resource consumption increases as asthma severity increases
Relative cost of medications is higher for
patients with less severe asthma
Peak flow was not related to asthma severity
Resource consumption was 2 – 3 times
higher in natural units
Resource consumption was 6 times higher
in monetary units (in Spain)