Insurance Parity and the Use of Outpatient
Mental Health Care following a Psychiatric
Hospitalization
Amal Trivedi, MD
Shailender Swaminathan, PhD
Vince Mor, PhD
Background

Historically, mental health services have had
larger cost sharing requirements than physical
health services
Some plans have excluded mental health services
from benefit package
 Copayments/coinsurance typically greater for mental
health
 Plans more likely to impose limits on coverage

Parity

Federal legislation passed in 2008 required
equivalent benefits for mental and physical
conditions
Same levels of cost-sharing
 Equivalent restrictions
 Law only applies to group health plans in firms with
more than 50 employees

Effects of Mental Health Parity

Federal Employee Health Benefits Program



After mandating parity, no significant increase in
spending and utilization compared to control plans
State parity laws not associated with increased
use of mental health services
Very little known about the effect on quality of
care
Objective


What are the cost sharing requirements for
mental health services compared to physical
health services in Medicare health plans?
What is the effect of health insurance parity on
quality of mental health care?

Follow-up in 7 and 30 days after hospitalization for
mental illness
Methods - Data

Medicare HEDIS data - 2001-6


Medicare enrollment file – 2001-6


Demographic characteristics
Plan benefits data 2001-6


Information on quality of care for 5-6 million MMC enrollees
per year
Required copayment or coinsurance for primary care,
specialist, and mental health care
Interstudy Competitive Edge database

Health plan organizational characteristics
Methods – Independent Variable


Recorded each plan’s required copayment for
mental health, specialist, and primary care visit
Classified plans into 3 groups:
Full parity: Cost-sharing for mental health visit equal
to primary care visit
 Intermediate parity: Cost-sharing for mental health
visit > primary care but <= to a specialist visit
 No parity: Cost-sharing for mental health visit >
than specialty and primary care

Methods-Dependent Variables



Follow-up visit after hospitalization for a mental
illness within 7 days
Follow-up visit after hospitalization for a mental
illness within 30 days
Indicators apply to 43892 enrollees from 2002-6
Methods - Analyses

Constructed regression models predicting
adherence to the indicators as a function of
parity status, controlling for:


Age, sex, race, area-level income and education, plan
size, plan age, modeltype, profit status, census
regions, and clustering within plan
Difference-in-differences analysis of 10 plans
that dropped full parity compared to 10 matched
controls
Parity for Outpatient Mental and Physical Health
Services in Medicare Health Plans, 2001-2006
Trivedi, A. N. et al. JAMA 2008;300:2879-2885.
Cost Sharing for Outpatient Mental and Physical
Health Services in Medicare Health Plans, 2001-2006
Trivedi, A. N. et al. JAMA 2008;300:2879-2885.
Sociodemographic and Health Plan Characteristics of
Enrollees, by Mental Health Parity
No Parity
(n=24220)
Intermediate
Parity
(n=19510)
Full Parity
(n=4348)
Mean Age (Years)
65
65
67
Female (%)
60
59
61
Black (%)
13
11
9
Below Poverty†
11
10
10
Some College or
Above‡
35
32
33
Figure 2. Rates of 7 day and 30 day Follow-up after Hospitalization for a
Mental Illness, by Health Plan Parity Status
Follow-up Rate (%)
100
80
64.3
60
51.8
57.1
45.3
40
32.4
37.2
20
0
Follow-up in 7 days
No parity
Follow-up in 30 days
Intermediate parity
Full Parity
Table 3. Adjusted Effect of Mental Health Parity Status
on 7 and 30 day follow-up visits after hospitalization for Mental
Illness
Adjusted estimate
No
Parity
Intermediate Parity
No Parity
Followup in 7
days
Ref
3.0 %
10.5 %
(95%CI -0.5, 6.5)
P=0.10
(95%CI 3.8, 17.1)
p=0.002
Followup in 30
days
Ref
4.0%
10.9 %
(95% CI 0.2,7.8)
p=0.04
(95%CI 4.6, 17.3)
p<0.001
Table 4. Change in Adherence rates in plans that dropped parity
compared to plans that maintained full parity
Measure
Plan
type
F/up in
7 days
F/up in
30 days
Year
before
change
(%)
Year
after
change
∆
∆-∆
Adj ∆-∆
p
Dropped 46.9
full
parity
35.7
-11.2
20.2
19.0
0.003
Maintain 45.8
ed full
parity
54.8
+9.0
Dropped 64.8
full
parity
57.4
--7.7
Maintain 68.5
ed full
parity
76.0
(95%CI 6.6, 31.3)
-15.1
-14.2
(95% CI
4.5, 23.9)
+7.5
0.007
Table 4. Change in Adherence rates in plans that dropped parity
compared to plans that maintained full parity
Measure
Plan
type
F/up in
7 days
F/up in
30 days
Year
before
change
(%)
Year
after
change
∆
∆-∆
Adj ∆-∆
p
Dropped 46.9
full
parity
35.7
-11.2
20.2
19.0
0.003
Maintain 45.8
ed full
parity
54.8
+9.0
Dropped 64.8
full
parity
57.4
--7.7
Maintain 68.5
ed full
parity
76.0
(95%CI 6.6, 31.3)
-15.1
-14.2
(95% CI
4.5, 23.9)
+7.5
0.007
Table 4. Change in Adherence rates in plans that dropped parity
compared to plans that maintained full parity
Measure
Plan
type
F/up in
7 days
F/up in
30 days
Year
before
change
(%)
Year
after
change
∆
∆-∆
Adj ∆-∆
p
Dropped 46.9
full
parity
35.7
-11.2
20.2
19.0
0.003
Maintain 45.8
ed full
parity
54.8
+9.0
Dropped 64.8
full
parity
57.4
--7.7
Maintain 68.5
ed full
parity
76.0
(95%CI 6.6, 31.3)
-15.1
-14.2
(95% CI
4.5, 23.9)
+7.5
0.007
Table 4. Change in Adherence rates in plans that dropped parity
compared to plans that maintained full parity
Measure
Plan
type
F/up in
7 days
F/up in
30 days
Year
before
change
(%)
Year
after
change
∆
∆-∆
Adj ∆-∆
p
Dropped 46.9
full
parity
35.7
-11.2
20.2
19.0
0.003
Maintain 45.8
ed full
parity
54.8
+9.0
Dropped 64.8
full
parity
57.4
--7.7
Maintain 68.5
ed full
parity
76.0
(95%CI 6.6, 31.3)
-15.1
-14.2
(95% CI
4.5, 23.9)
+7.5
0.007
Table 4. Change in Adherence rates in plans that dropped parity
compared to plans that maintained full parity
Measure
Plan
type
F/up in
7 days
F/up in
30 days
Year
before
change
(%)
Year
after
change
∆
∆-∆
Adj ∆-∆
p
Dropped 46.9
full
parity
35.7
-11.2
20.2
19.0
0.003
Maintain 45.8
ed full
parity
54.8
+9.0
Dropped 64.8
full
parity
57.4
--7.7
Maintain 68.5
ed full
parity
76.0
(95%CI 6.6, 31.3)
-15.1
-14.2
(95% CI
4.5, 23.9)
+7.5
0.007
Table 4. Change in Adherence rates in plans that dropped parity
compared to plans that maintained full parity
Measure
Plan
type
F/up in
7 days
F/up in
30 days
Year
before
change
(%)
Year
after
change
∆
∆-∆
Adj ∆-∆
p
Dropped 46.9
full
parity
35.7
-11.2
20.2
19.0
0.003
Maintain 45.8
ed full
parity
54.8
+9.0
Dropped 64.8
full
parity
57.4
--7.7
Maintain 68.5
ed full
parity
76.0
(95%CI 6.6, 31.3)
-15.1
-14.2
(95% CI
4.5, 23.9)
+7.5
0.007
Limitations

Adverse selection into plans without parity
Cohort of persons with severe mental illness
 Similar demographic composition
 Consistent findings in cross-sectional and
longitudinal analyses


Plans may have other mechanisms to reduce use
of mental health care
Conclusions



~80% of Medicare managed care enrollees were
required to pay higher copayments for mental
health services compared to primary or specialty
care
Little evidence of selection by parity status
Full parity plans have substantially higher
performance on two important measures of
mental health care quality
Implications



Federal parity legislation did not clarify whether
parity means equivalent cost-sharing for primary
or specialty care
Federal legislation left out many groups
Mandating parity in cost-sharing for primary
care and mental health care could yield
substantial improvements in quality of mental
health care
Unintended Consequences of Increasing
Ambulatory Copayments among the Elderly
Amal Trivedi, MD, MPH
Husein Moloo, MPH
Vince Mor, PhD
Alpert Medical School of Brown University
Providence VA Medical Center
Supported by a Pfizer Health Policy Scholars Award
Background


Increasing the
copayment for
ambulatory care reduces
the number of
outpatient visits
Ambulatory
copayments have
increased markedly in
recent years
Background


If patients forego important outpatient care,
they may be more likely to use acute hospital
care
Few studies of the hospital utilization offsets
from greater ambulatory copayments
RAND Experiment found no increased hospital
admissions in group exposed to an outpt deductible
 RAND HIE excluded the elderly

Aims


Assess whether increased ambulatory
copayments are associated with increased use of
hospital care among the elderly
Determine whether increases in copayments has
differential effects among vulnerable
populations

low-income and education, black race, and chronic
disease
Methods – Data Sources



Individual-level utilization data from all
Medicare health plans from 2001-2006 linked to
Medicare enrollment file
Health plans benefits data for all Medicare plans
Interstudy Competitive Edge for health plan
organizational characteristics
Methods – Study Population




Identified 18 Medicare plans that increased
ambulatory copayments between 2001 and 2006
without changing prescription drug benefits
Randomly matched these plans to 18 control
plans that did not increase copayments
Plans were matched on the basis of census
region, tax status, and model type
Final sample: 899,060 enrollees in 36 plans
Methods – Statistical Analyses




Difference-in-differences design
Assessed change in inpatient and outpatient
utilization in plans that increased copayments
compared to concurrent trends in control plans
Used GEE to account for clustering by plan,
repeated measures
Stratified analyses by race, income, education,
presence of chronic medical conditions
Cost-Sharing in Case and Control
Medicare Plans
Case Plans that Increased
Ambulatory Copayments
Control Plans where Ambulatory
Copayments were Unchanged
Year before
increase
Year after
increase
Year before case Year after case
plans increased plans
copayment
increased
copayment
Primary Care
$7.38
$14.38
$8.33
Unchanged
Specialty Care
$12.66
$22.05
$11.38
Unchanged
Inpatient
$148.33
$329.17
$111.11
$177.08
Enrollee Characteristics of Case and
Control Medicare Plans
Case Plans that Increased Control Plans where Ambulatory
Ambulatory Copayments Copayments were Unchanged
Year before
increase
Year after
increase
Year before case Year after case
plans increased plans increased
copayment
copayment
Mean Age, y
74.2
74.4
74.6
74.8
Female, %
58
59
57
58
Black, %
9
8
5
5
Below
poverty, %
10
10
9
9
College
attendance, %
31
32
35
34
Change in Rates of Use of Outpatient and Inpatient Care in Case and Control
Medicare Plans
Measure
Type of plan
Annual Rates Per 100
Enrollees
Yr before
Change
Case Plans
702.0
Change
Yr after
Change
720.5
Control Plans
753.4
798.9
+45.5
Increased
copayments
25.3
27.6
2.3
Copayments
unchanged
25.8
26.1
Unadjusted
Adjusted
(95% CI)
-27.0
-19.8
(-16.6,-23.1)
2.0
2.3
(1.8-2.7)
+18.5
Outpatient
Visits
Annual
Inpatient
Admissions/
100
Enrollees
Between-Group Difference
0.3
Change in Rates of Use of Outpatient and Inpatient Care in Case and Control
Medicare Plans
Measure
Type of plan
Annual Rates Per 100
Enrollees
Yr before
Change
Annual
Outpatient
Visits/100
Enrollees
Inpatient
Admissions
Change
Yr after
Change
Increased
copayments
702.0
Copayments
unchanged
753.4
798.9
+45.5
Case Plans
25.3
27.6
2.3
Control Plans
25.8
720.5
26.1
Between-Group Differencea
Unadjusted
Adjusted
(95% CI)b
-27.0
-19.8
(-16.6,-23.1)
2.0
2.3
(1.8-2.7)
+18.5
0.3
Change in Rates of Use of Outpatient and Inpatient Care in Case and Control
Medicare Plans
Measure
Type of plan
Annual Rates Per 100
Enrollees
Yr before
Change
Annual
Outpatient
Visits/100
Enrollees
Annual
Inpatient
Admissions/
100
Enrollees
Inpatient
Days
% with
inpatient
days
Change
Yr after
Change
Increased
copayments
702.0
Copayments
unchanged
753.4
798.9
+45.5
Increased
copayments
25.3
27.6
2.3
720.5
25.8
26.1
0.3
Case Plans
133.5
145.9
+12.4
Control Plans
125.6
126.7
+1.1
Case Plans
15.39
16.30
+0.91
15.86
16.15
Unadjusted
Adjusted
(95% CI)b
-27.0
-19.8
(-16.6,-23.1)
2.0
2.3
(1.8-2.7)
11.3
13.7
(10.4-16.9)
0.62
0.74
(0.5-0.9)
+18.5
Copayments
unchanged
Control Plans
Between-Group Differencea
0.29
Annual Inpatient
Admissions/100 Enrollees
Difference-in-differences Estimates by Area-level
Income and Education
5
4
3
2
1
0
Poverty
Education
High
Med
Low
Annual Inpatient
Admissions/100 Enrollees
Difference-in-differences Estimates by Race
8
7
6
5
4
3
2
1
0
Race
White
Black
Other
Annual Inpatient
Admissions/100 Enrollees
18
16
14
12
10
8
6
4
2
0
Difference-in-differences Estimates for Persons with
Chronic Disease
Race
Hypertension Diabetes
Myocardial Infarction
Limitations




Non-random assignment of enrollees in health
plans
Only followed enrollees for a max of 3 years
Unable to distinguish between effects of
increasing primary care vs. specialty care copays
No information on primary diagnoses of
inpatient and outpatient visits
Conclusions


Increasing ambulatory copayments reduced use
of outpatient care but was offset by a substantial
rise in hospital use
Effects magnified among vulnerable groups with
low socioeconomic status and chronic disease
Implications



Assuming an average outpatient visit of $60, then the
average Medicare plan that raised ambulatory
copayments would avert $7150/100 enrollees in
annual outpatient spending
Assuming an average cost of $11,065 per admission,
the plan would pay over $25000 /100 enrollees in the
year after the copayment increase
Increasing ambulatory copayments may have adverse
clinical and economic consequences
Table 3. Baseline Utilization of Enrollees that Exited and Remained in
Case and Control Medicare Plans
Acute Hospital
Admission/100 Enrollees
Type of plan
Case Plans that Increased
Ambulatory Copayments
Control Plans with
Unchanged Ambulatory
Copayments
Exited plan
(n=43641)
22.0
Remained in plan
(n=314,245)
20.2
Difference
(95% CI)
1.8
(1.2, 2.4)
Exited plan
(n=35307)
18.9
Remained in plan
(n=281,505)
20.9
Difference
(95%CI)
-2.0
(-2.7, -1.3)
Table 4. Change in Rates of Use of Outpatient and Inpatient Care in a
Cohort of Continuously Enrolled Beneficiaries in Case and Control
Medicare Plans
Type of plan
Annual Outpatient
Annual Acute
Visits/100 Enrollees Hospital
Admission/100
Enrollees
Case Plans that
Increased
Ambulatory
Copayments
(n=330,782)
Year before
increase
699.3
20.2
Year after increase
747.1
28.5
Change
47.8
8.3
Control Plans
with Unchanged
Ambulatory
Copayments
(n=291,980)
Year before change 766.2
20.9
Years after change
825.5
27.3
Difference
59.3
6.4
Between-group
difference
Unadjusted
-11.5
1.9
Adjusted(95% CI)
-10.2 (-13.4, -7.0)
2.1 (1.6, 2.5)
Sensitivity Analysis of Health Plans with 2 years of unchanged
Ambulatory and Prescription Drug Benefits prior to Ambulatory
Copayment Increase
Case Plans
2 years before
Copayment
Increase
26.1 (SE 1.0)
Year before
Copayment
Increase
26.1 (SE 1.0)
Control Plans 27.3 (SE 0.7) 27.7 (0.7)
Year after
Copayment
Increase
27.9 (SE 1.0)
27.5 (SE 0.7)