Self- reported Effects of Prescription Drug
Cost- Sharing: Decreased Adherence and
Increased Financial Burden
Introduction
►
Mary Reed, MPH1
►
Vicki
Richard Brand, PhD2
Bruce Fireman, MA1
Joseph P. Newhouse, PhD3
Joseph V. Selby, MD, MPH1
John Hsu, MD, MBA, MSCE1
Drug expenditures are increasing each year in the US
Patients are paying for an increasing share for their
prescription drugs: costcost-sharing
Fung1
1Kaiser
►
CostCost-sharing effects may be influenced by patient knowledge
►
Limited information about:
– Patient knowledge about their prescription drug costcost-sharing
– How patients behave when faced with this costcost-sharing
Permanente - Division of Research
of California, San Francisco
University
2University
3Harvard
Academy Health Annual Research Meeting
June 7, 2004
Purpose
►
To examine patient knowledge of their prescription drug
costcost-sharing level:
–
–
–
►
Any prescription drug costcost-sharing?
Structure of prescription drug costcost-sharing (multi(multi-tier
copayments and benefit caps)?
Amount of drug costcost-sharing (copayment amounts and
benefit cap amounts)?
To examine selfself-reported patient behavioral responses to
prescription drug costcost-sharing:
–
–
Do patients report taking less than the prescribed amount
of a drug (adherence)?
Do patients report having to struggle to pay for their
prescription drugs (burden)?
Questionnaire Measures - Adherence
►
“Because of the amount you had to pay, have you”:
– “taken less than the prescribed amount to make it last
longer”
– “not filled a prescription for a new medication”
– “stopped refilling a prescription”
Methods – Design/Population/Sample
►
CrossCross-sectional Design: Telephone interviews in 2003
►
Population:
– Active members in a large, prepaid integrated delivery
system (IDS)
– Age 18 years or more
– EnglishEnglish-speaking
– Commercial or Medicare insurance
►
Stratified random sample:
– A: General Population (30%)
– B: Members over age 65 (70%)
►
Population is a subset of a larger study on clinical and
economic effects of costcost-sharing
Questionnaire Measures - Burden
►
“Because of the amount you had to pay, have you”:
– “switched to a cheaper medication (e.g. generic)”
– “gotten free medication samples from a doctor”
– “gone to a nonnon-Kaiser pharmacy instead”
– “gotten help paying for medications through an
[assistance] program”
– “borrowed $ to pay for medications”
– “gone without some necessity such as food, rent, heat,
or other basics”
– “bought a prescription medication in another country”
– “bought a medication from an internet pharmacy”
1
Methods – Analysis
Figure 1. Study Design: Interview Participation n=932 (72%)
►
Models: Multivariate logistic regression
►
Predictor Measure:
KPNC Adult Population: Commercial and Medicare Population
– Perceived/Actual Drug costcost-sharing: Generic Copayment ($),
BrandBrand-Generic Copayment ($), Any Benefit Cap
►
Age 65+ (70%)
n=1190
Overall Population (30%)
n=510
Outcome Measures
– Decreased Adherence
– Financial Burden
►
Members Randomly Selected and Contacted for Interview
n=1700 [2 Strata]
Ineligible*
n=147
Covariates
– SocioSocio-demographic: age, gender, race/ethnicity, marital
status, household income, educational level
– Clinical: selfself-reported health status, selfself-reported number of
prescription drugs in previous 12 months, comorbidity
(DxCG)
Interviewed
n=254
(70%)
Refused
n=251
(27%)
Interviewed
n=678
(73%)
*Ineligible = deceased, incapable of phone interview (e.g. hearing difficulties,
dementia), non-English speaker, unable to be contacted
Table 2. Knowledge of Drug CostCost-Sharing
Table 1. Participant Characteristics
Characteristic
Ineligible*
n=261
Refused
n=109
(30%)
(n=932)
%
Total
Sample A:
Overall Pop.
(n=254)
%
Sample B:
Age 65+
(n=678)
%
Age 65+
77.7
14.2
100.0
Female Gender
55.8
50.5
58.8
Non-white Race
26.2
35.5
22.7
Any Cost-Sharing
Cost Sharing Type
Amount of Cost Sharing
SelfReport
KP
Actual
Correctly
Reported
Underestimate
Exactly
Correct
%
%
%
%
%
%
Generic Copay
92.9
82.3
84.9
8.0
70.0
22.0
Overestimate
Education: less than College Graduate
67.2
59.0
69.7
Married
63.9
71.6
61.6
Brand Name Tiered Copay
61.2
74.4
73.8
33.3
50.5
16.2
Household Income: < $35,000
43.2
18.8
51.3
Benefit Cap
31.2
33.4
85.6
5.0
59.4
35.6
Self Reported Health: Excellent or Very Good
44.4
53.7
41.6
Persons with Any Prescription Meds w/in 12 mos.
90.9
82.1
93.5
Persons with Any ED Visits within 12 mos.
23.8
21.7
24.7
Figure 2. SelfSelf-Reported Behavioral Response to CostCost-sharing:
Decreased Adherence
Figure 3. SelfSelf-Reported Behavioral Responses to CostCost-sharing:
Increased Burden
20.5
Burden: Any Behavior (N=152)
10.8
Any change in Adherence (N=80)
10.9
Sw itched to cheaper medication (N=80)
2.3
Received free samples (N=17)
6.2
Taking less than prescribed (N=46)
0.1
Bought medications on the internet (N=1)
0.7
Used pharmacy assistance program (N=5)
6.1
Not re-filling a prescription (N=45)
1.5
Bought medications outside of US (N=11)
6.4
Not filling a new prescription (N=47)
3.1
Gone to non-Kaiser pharmacy (N=23)
5
Borrow ed $ to pay for medications (N=37)
0
2
4
6
8
10
Percent of Respondents (%)
12
3.3
Gone w ithout a necessity (N=24)
2.7
Borrow ed medication from friend/family (N=20)
0
3
6
9
12
15
18
Percent of Respondents (%)
21
2
Table 3. Behavioral Response to Cost-sharing:
Decreased Adherence Multivariate Logistic Regression
Characteristic
Table 4. Behavioral Response to CostCost-sharing:
Increased Burden Multivariate Logistic Regression
Characteristic
Self-Reported
Cost-Sharing
Actual CostSharing
OR
95% CI
OR
95% CI
1.04*
0.99, 1.09
0.96
0.81, 1.14
1.01†
1.00, 1.03
1.04
0.97, 1.11
1.94†
1.16, 3.25
1.76
0.74, 4.19
Age 65+
0.42†
0.20, 0.86
0.39†
0.16, 0.92
0.84, 2.83
Female Gender
1.96†
1.15, 3.35
1.54
0.84, 2.83
0.73, 2.49
Non-White Race
1.30
0.76, 2.24
1.35
0.24, 0.81
Education: less than College Graduate
1.27
0.73, 2.22
0.44
Self-Reported
Cost-Sharing
Actual CostSharing
OR
95% CI
OR
Generic Copay ($)
1.04
0.99, 1.10
0.96
0.81, 1.14
Generic Copay ($)
Brand – Generic Copay ($)
1.01†
1.00, 1.03
1.04
0.97, 1.11
Brand – Generic Copay ($)
Any Benefit Cap
2.37‡
1.26, 4.47
1.76
0.74, 4.19
Any Benefit Cap
Age 65+
0.57
0.23, 1.40
0.39†
0.16, 0.92
Female Gender
1.73
0.89, 3.36
1.54
Non-White Race
1.13
0.57, 2.25
1.35
95%CI
Drug Cost-Sharing:
Drug Cost-Sharing:
Education: less than College Graduate
0.54*
0.28, 1.04
0.44‡
Married
1.42
0.75, 2.72
1.43
0.79, 2.61
Married
1.59*
0.73, 2.49
‡
0.24, 0.81
0.93, 2.72
1.43
0.79, 2.61
Household Income < $35,000
3.08‡
1.50, 6.35
3.03‡
1.54, 5.98
Household Income < $35,000
3.07‡
1.73, 5.47
3.03‡
1.54, 5.98
Health Excellent or Very Good
0.80
0.41, 1.56
0.90
0.49, 1.65
Health Excellent or Very Good
0.68
0.40, 1.17
0.90
0.49, 1.65
Number of RX’s used in 12 mos.: 0,1,2-4,5+
1.76†
1.04, 2.99
1.95‡
1.20, 3.18
Number of RX’s used in 12 mos.: 0,1,2-4,5+
1.46*
0.97, 2.19
1.95‡
1.20, 3.18
Models Adjusted for Comorbidity
Models Adjusted for Comorbidity
*p=<0.10, †p=<0.05, ‡p=<0.01, CI= Confidence Interval
*p=<0.10, †p=<0.05, ‡p=<0.01, CI= Confidence Interval
Limitations
►
Single IDS with a range of delivery options
►
EnglishEnglish-speakers only
►
Modest levels of costcost-sharing
►
SelfSelf-reports of behavioral responses
►
No measure of clinical impact of behavioral responses
Conclusions
►
►
Patients appeared to have general knowledge of their
prescription drug costcost-sharing, but limited knowledge about
the amounts
Nearly one in four patients changed their behavior in
response to their perceived level of prescription drug costcostsharing
– Over one in ten patients did not take their drugs as
prescribed because of their perceived level of drug costcostsharing
– Nearly one in five patients reported an increased burden in
paying for their prescription medications
Implications
►
►
►
The impact of drug costcost-sharing on behavior may be
attenuated due to limited knowledge of actual costcost-sharing
amounts
Persons with more drug use or lower income may be more
likely to change their behavior in response to drug costcostsharing
Additional research is needed on the clinical and economic
ramifications of prescription drug costcost-sharing
3