Is More Better? Examining the Relationship pp y
y
Between Provider Supply and Ambulatory Care Sensitive Hospitalizations?
AcademyHealth – Organizational Factors and Care Delivery
Organizational Factors and Care Delivery
June 28, 2010
Acknowledgments
g
• Agency for Healthcare Research and Quality (AHRQ)
• California Office of Statewide Health Planning and Development (OSHPD)
Development (OSHPD)
• Jeff Alexander, Jane Banaszak‐Holl, Rich Hirth, Rick J ff Al
d J
B
k H ll Ri h Hi th Ri k
Price
Agenda
g
• Background on ambulatory care sensitive hospitalizations (ACSH)
• Design, analytic strategy, and results
Design, analytic strategy, and results
• Conclusions and policy implications
C l i
d li i li ti
ACSH Defined
• Definition: hospitalizations for health conditions that potentially could have been avoided with timely and effective outpatient care
• AHRQ Prevention Quality Indicator for 14 conditions
• Acute care conditions: dehydration, perforated appendix, pneumonia, urinary tract infection, low birth weight*, amputation related to diabetes*
• Chronic care conditions: angina, asthma, COPD, CHF, hypertension, short‐
term diabetes complications, long‐term
term diabetes complications, long
term diabetes complications, diabetes complications,
uncontrolled diabetes without complications * Low volume conditions excluded from this study.
Low volume conditions excluded from this study.
Incidence and Cost of ACSH in the U.S., 2004
,
• Nearly 4.4 million admissions
• One in five Medicare admissions
• $30.8 billion in hospital costs
• CHF and pneumonia most common conditions, accounting for over half of all ACSH costs
(Jiang, Russo, et al., 2008)
ACSH Conceptual Frameworks
p
• Access to care
• Two types of factors used to explain ACSH
Two types of factors used to explain ACSH
• Population characteristics
• E.g., race/ethnicity, age, gender, SES, health status, payer/insurance status
• Provider supply • E.g., physicians, community health centers
• Coordination of care
• Relational properties of health care delivery system
Relational properties of health care delivery system
Objectives of Study
j
y
• Expand the provider types considered when examining the relationship between provider supply and ACSH rates
• Include home health agencies, nursing homes, physician organizations, and staff/group model HMOs • Examine potential non‐linear relationships of provider supply
• Examine alternative operationalization of provider supply
Examine alternative operationalization of provider supply
• Composition (vs. capacity)
Study Setting
y
g
• 58 California markets from 1998‐2005
• Market defined at the county‐level
y
• Unit of analysis: market‐year hospitalization rate
• Inclusive of multiple provider types responsible for p p
yp
p
primary care Design & Analytic Strategy
g
y
gy
• Pooled, cross‐sectional design
• Linear mixed model to account for repeated observations
• Data sources
• AHA Annual Survey
• California Office of Statewide Health Planning and Development (OSHPD)
C lif i Offi
f St t id H lth Pl
i
dD l
t (OSHPD)
• Hospital discharge data
• Cost and utilization data for hospitals, CHCs, home health agencies, SNFs
• Area Resource File
Variables
• Dependent variable • Number of ACSH / Number of total admissions (log transformed)
• Aggregated conditions (acute care, chronic care, all conditions)
Aggregated conditions (acute care, chronic care, all conditions)
• Condition‐specific rates (e.g., CHF, COPD)
• Independent variables • Provider supply (per 1,000 residents)
• Capacity (per 1,000 residents): community health centers, hospitals, home health agencies, physician organizations, skilled nursing facilities, staff/group model HMOs
• Composition (relative to hospitals): community health centers, home health agencies, physician organizations, skilled nursing facilities, staff/group model HMOs
• Controls
• Gender, race/ethnicity, age, geography (urban vs. rural), socio‐economic status (SES), health status, market size, outpatient utilization
ACSH as a Percentage of All Hospitalizations (ACSH t ) 1998 2005
(ACSH rate), 1998‐2005
Acute conditions
Chronic conditions
Combined conditions
18%
16%
14%
12%
10%
8%
6%
4%
2%
0%
1998
1999
2000
2001
2002
2003
2004
2005
Descriptives, 2005
p
,
P id
Provider capacity
it
M
Mean
P id
Provider composition
iti
M
Mean
C t l
Controls
M
Mean
CHCs per 1,000
0.05
CHCs per hospital
2.54
% Male
51%
p
p
,
Hospitals per 1,000
0.03
N/A
/
% African‐
American
3%
HHAs per 1,000
0.02
HHAs per hospital
1.26
% Hispanic
23%
HMO per 1 000
HMO per 1,000
0 04
0.04
HMOs per hospital
HMOs per hospital
3 52
3.52
% with college with college
educ.
14%
POs per 1,000
0.01
POs per hospital
0.88
% uninsured
18%
SNF
SNFs per 1,000
1 000
0 02
0.02
SNF per hospital
SNFs
h i l
1 97
1.97
%
% ages 0‐14
0 14
22%
% ages 15‐64
66%
% ages over 65
% ages over 65
12%
N=58 markets
Should Other Provider Types Be Considered?
yp
T t l ACSH R t
Total ACSH Rate
A t
Acute care ACSH Rate
ACSH R t
Ch i
Chronic care ACSH Rate
ACSH R t
CHCs per 1,000
‐0.60*
‐0.54 ‐0.45
Hospitals per 1,000
p
p
,
‐3.11
3.11
‐1.65
1.65 ‐1.91***
1.91
HHAs per 1,000
‐1.00*
‐0.31
0.68
HMO per 1 000
HMO per 1,000
0 63
0.63 0 34
0.34
‐3.38
3 38
POs per 1,000
‐1.32 ‐3.78
0.35
SNFs per 1,000
‐0.88***
‐2.56***
0.96
*p<0.05;
p 0.05; **p<0.01;
p 0.01; ***p<0.001
p 0.001
Non‐Linear Relationships? p
Total ACSH Rate
Total ACSH Rate
Acute care ACSH Rate
Acute care ACSH Rate
Chronic care ACSH Rate
Chronic care ACSH Rate
CHCs per 1,000
0.20
0.22
0.93
CHCs per 1,000 2
‐3.92
‐4.40
‐5.91
Hospitals per 1,000
‐1.97
0.80 ‐2.93
Hospitals per 1,000 2
‐5.82
‐12.31
‐2.53
HHAs per 1,000
‐1.10
‐2.16
0.10
HHAs per 1,000 2
1.87
18.33
‐17.15
HMOs per 1,000
0.64 0.52
0.63
2
p
,
HMOs per 1,000 1.42
2.72
0.92
POs per 1,000
‐27.44* ‐22.05
‐25.48*
POs per 1,000 2
887.10**
761.87*
886.02*
SNFs per 1 000
SNFs per 1,000
‐0 49
‐0.49
0 83
0.83
‐1 49*
‐1.49
SNFs per 1,000 2
‐2.11
‐18.16***
9.74**
*p<0.05; **p<0.01; p<0.001
Alternative Measurement of Provider Supply? pp y
T t l ACSH R t
Total ACSH Rate
A t
Acute care ACSH Rate
ACSH R t
Ch i
Chronic care ACSH Rate
ACSH R t
CHCs per hospital
‐0.01
‐0.01 ‐0.01
HHAs p
per hospital
p
‐0.03*
0.03
‐0.03
0.03
‐0.03*
0.03
HMO per hospital
0.04***
0.04**
0.03*
POs per hospital
0.01
0.001
0.01
SNFs per hospital
‐0.01
‐0.02*
‐0.01
*p<0.05; **p<0.01; p<0.001
Provider Capacity by ACSH Condition
p
y y
HHA
HMO
PO
SNF
Dehydration
0.18
‐3.78
0.56
1.18
5.46
‐0.32
Perforated appendix
pp
1.30
5.22
1.16
‐1.24
3.38
‐0.87
‐1.18
0.11
‐0.17
0.20
‐7.59
‐1.77
1.81
‐5.14
1.63
1.36
0.56
1.02
Angina
‐1.89
‐10.50
‐1.18
3.08
29.51
‐0.90
Asthma
‐0.41
1.23
2.12
‐0.01
‐5.47
‐1.36
CHF
‐0.75
‐2.62
‐3.54
0.37
‐0.31
‐1.51
COPD
‐0.83
‐2.56
0.11
0.91
6.14
0.77
Diabetes, short‐term comp
0.72
‐1.79
‐4.58
0.93
4.52
‐2.36
Diabetes, long‐term comp
1.47
‐5.00
0.56
1.20
2.91
0.58
‐1.08
‐2.94
3.16
2.63
0.54
0.30
2.46
‐7.35
‐7.40
5.45
7.66
1.75
Pneumonia
UTI
Hypertension
Uncontrolled diabetes
*Shading indicates relationship significant at p<0.05 or smaller.
g
p g
p
Chronic conditions
Hospital
Acute cconditions
CHC
Provider Composition by ACSH Condition
p
y
HMO‐
hospital
PO‐
hospital
SNF‐
hospital
Dehydration
0.01
‐0.02
0.02
‐0.01
‐0.01
Perforated appendix
0.01
0.01
0.01
0.03
‐0.01
‐0.01
‐0.02
0.03
‐0.04
‐0.02
0.03
‐0.06
0.05
‐0.03
0.01
Angina
‐0.07
‐0.04
0.11
0.13
‐0.03
Asthma
0.01
0.01
‐0.01
0.02
‐0.01
CHF
0 02
0.02
0 02
0.02
0 02
0.02
0 05
0.05
0 01
0.01
‐0.03
0.02
0.03
0.02
0.01
Diabetes, short‐term comp
0.01
‐0.01
0.03
0.08
‐0.05
Diabetes, long‐term comp
i b
l
0.02
0.01
0.03
‐0.01
‐0.03
Hypertension
‐0.09
‐0.02
0.09
0.02
‐0.01
Uncontrolled diabetes
‐0.02
‐0.21
0.05
‐0.05
0.04
Pneumonia
UTI
COPD
*Shading indicates relationship significant at p<0.05 or smaller.
Chrronic conditions
HHA‐
hospital
Acutee conditions
CHC‐
hospital
Provider Capacity vs. Provider Composition by ACSH C diti
ACSH Condition
CHC
Hospital
N/A
Perforated appendix
N/A
Pneumonia
Negative
N/A
UTI
Negative
N/A
Angina
Negative
N/A
N/A
CHF
N/A
COPD
N/A
Diabetes, short‐term comp
N/A
Positive
Negative
Positive
Negative
Negative
Positive
Positive
Hypertension
Negative
N/A
Positive
Relationship significant only in
provider capacity models.
Relationship significant only in
provider composition models.
Positive
Negative
N/A
Negative
Negative
Positive
Positive
N/A
SNF
Positive
Diabetes, long‐term comp
Uncontrolled diabetes
PO
Negative
Chronic cconditions
Asthma
HMO
Acute con
nditions
Dehydration
HHA
Positive
Relationship significant in
both provider supply models.
Conclusions
• Provider types other than physicians and community health centers important for explaining variations across markets
• Effects of supply depend on the way supply is conceptualized and operationalized
conceptualized and operationalized
• Effects
Effects of supply vary across specific clinical conditions and of supply vary across specific clinical conditions and
aggregated rates mask significant relationships that exist for specific clinical conditions
specific clinical conditions Policy Implications
y p
• Importance of other provider types
Importance of other provider types
• Who is accountable for ACSH? How is policy developed that is more inclusive of other provider types and
that is more inclusive of other provider types and
facilitates accountability?
• Recognition that supply is more than just capacity
• H
How are providers best distributed
id b di ib d to improve i
outcomes? • Appropriateness of aggregated measures
• How to balance parsimony with precision?