The Impact of Co-morbidity
2nd ACHRFAuckland, New Zealand8 November 2012
Dr John WrenPrincipal Research Advisor
ACC
Dr Barry GribbenCBG Health Research
Lauren ProsserSenior Policy Advisor
ACC
ACC Service Utilisation & Costs2012 - 2025
The Questions
WHAT is the effect of a health co-morbidity on ACC clients ?
˃ injury treatment claim rates (utilisation)
˃ duration of claim
˃ costs over time
WHAT are the cost effects on an aging population ?
WHAT are the policy implications ?
The Process
BUILT on the pilot studies reported in 2010 (Wren & Mason)
LINKED Primary Health Care data (GP Practice) with
Ministry of Health & ACC data using New Zealand NHI
˃ Random sample of 337,665 people
˃ Sample representative of the New Zealand population
Descriptive & Multivariate Statistical Analysis
Co-morbidities
Asthma
Chronic obstructive pulmonary disease
Ischaemic heart disease
Heart failure
Diabetes mellitus
Mental health condition
Cancer diagnosis
Osteoarthritis
Hypertension
Variables & Interactions
Age
Sex
Ethnicity
Socio-economic status (New Zealand social deprivation index)
Treatment utilisation
Claims duration
ACC Costs
Headline Statistical Results
Multivariate Model Analysis
Presence of a health co-morbidity was found to have a strong
statistically significant (95%) association with:
˃ increased service utilisation
˃ higher costs
The effects were independent of, and additional to, normal
health cost effects typically associated with age, gender,
ethnicity & socio-economic status
Headline Statistical Results
Presence of one or more health co-morbidities showed …
˃ 28% more claims
˃ 346% higher lump sum payments
˃ 59% higher medical treatment costs
˃ 39% more weekly compensation costs
OVERALL 59% more total ACC cash costs across all cost categories
… stronger relativity for some than others Average total cost per person per year (95% CI)
Cost relativity
0
200
400
600
800
1000
1200
1400
NoYesNoYesNoYesNoYesNoYesNoYesNoYesNoYesNoYes
DiabetesAsthmaCancerHeart FailureIHDMental HealthHyper-tensionStrokeOsteo-arthritis
Average total cost per annum NZD
Claim Utilisation
Medical Treatment Cost
Total Annual Cost
Total Annual ACC Cost is
attributable to
presence of co-morbidities in the
New Zealand population
$276 million (NZD, 2011)
Based on the analysis
10.7%
0
200
400
600
800
1000
1200
1400
1600
1800
2000
Mea
n c
ost
per
an
nu
m p
er p
erso
n
Age group
Average total cost per person Age group co-morbidity vs. no co-morbidity
Mean $ NO co-morbidity
Mean $ co-morbidity
Ageing Effects
Excess cost is the area of the gap between the two lines – largest gap is in the working age population
Modelling Ageing Effects to 2025
Expect this area to get bigger
Costs Attributable to Co-morbidities
Conclusions
Presence of a wide range of health co-morbidities in the
population has a real effect on injury compensation
treatment utilisation volumes and costs
To 2025, 10.7% to 12.7% of total annual ACC costs is
estimated to be attributable to presence of co-morbidities in
the population
It appears that although aging of the population means more
people have co-morbidities, this is counterbalanced by
relatively fewer people being in the age groups where the
cost differences are greater
Results are consistent with recent research from NCCI in
America about working age effects
Policy response Confirms and quantifies our assumptions – ACC appears to be paying
more than required to meet a person’s injury-related needs
But how big is the problem?
Within current legislative constraints? ACC is liable for injury costs unless an unrelated co-morbidity is ‘wholly or substantially’ the cause of the person’s ongoing incapacity
Where does the cost burden fall in the ACC Accounts? What is the impact on liability?
Policy questions:
How can ACC be smarter at managing the additional costs associated with co-morbidities?
Should the costs be shared with others, eg individuals or other agencies? How can ACC continue to deliver a client-centred service?
No silver bullet – distinguishing injury and non-injury related needs is difficult, particularly in the context of different funding systems and philosophies
Working through the policy issues and options
Potential responses could include:
cost-sharing arrangements
targeted risk and claims management
integrated assessment and services
injury prevention initiatives
reviewing assessment of individual entitlements
status quo?
Gribben, B. & Wren, J. ( 2012) The Impact of Health
Comorbidities on ACC Injury Treatment and Rehabilitation
Utilisation and Costs, and cost estimate to 2025 of effects in
an aging population.
CBG Health Research and ACC Research, Sep 2012.
Wren, J. & Mason, J. 2010. Results of Three Pilot Studies
Exploring & Quantifying Health Co-morbidity Effects on ACC
Injury Treatment Utilisation and Costs.
ACC.
For further information
Additional Slides
Health Literature
Pre-existing health co-morbidity effects on increased health service utilisation well-documented in recent World Health Organisation (WHO) reports
˃ Injured people are different from the non-injured population in terms of pre-existing morbidity
˃ Patients with higher numbers of co-morbidities utilise injury services more than patients with lower co-morbidities.
Cameron, Prudie, Kliewer et al., 2005)
Health co-morbidity (ICD-9-CM Chapter)
Rate Ratios* Injured/ Non-Injured *Adjusted for age, sex and place of
residence *
Source: Adapted from Cameron et al, 2005. Tables 4 and 5 respectively. Hospital Admissions Physician
Claims per 1000 person years
Mental Health disorders 9.31 3.50
Injury and poisonings 3.68 2.72
Blood diseases 3.36 1.53
Endocrine and metabolic 2.79 1.38
Musculoskeletal disorders 2.61 1.76
Nervous system diseases 2.35 1.42
Respiratory diseases 1.98 1.38
Circulatory diseases 1.70 1.21
Role of Mental Health, Alcohol and Psychological Traits
“There appears to an aetiological link between mental health
conditions and injury, particularly in relation to risk-taking
behaviours, alcohol misuse, and psychological traits such as
impulsivity, sensation-seeking, and risk-perception.”
(Cripps & Harrison, 2008. Briefing report for the Australian Institute of Health and
Welfare)
Health Literature
Increased injury risks, higher medical treatment costs
(including pharmaceutical services), workers compensation
costs, and poor work performance (presenteeism) have
consistently been associated with specific lifestyle risk
factors such as tobacco use (current and previous), obesity,
stress, and lack of regular physical activity among working
people in a variety of settings
(Studies published by Health Management Research Centre, and Others)
Workers Compensation Literature
Workers Compensation Literature
Considerable confidence the excess risk from health co-
morbidities accounts for at least 25% to 30% of medical
costs per year across a wide variety of companies,
regardless of industry or demographics
The biggest cost factors are the cost of extra treatment
utilisation, and medical costs associated with the
complications of a co-morbidity
(Studies published by Health Management Research Centre)
ACC Claims Costs
Highly skewed
All Results Significant at 95%
Multivariate Analysis
Future Cost Calculation
The proportion of ACC costs attributable to chronic illness in any given out year is a function of:
the population structure (the matrix Nij)
the number of years from our baseline, n.
Pij, r, $ccij and $nccij are all constants calculated earlier, or assumed.
ij
nijij
nijijij
ijijij
nijij
iPncciPccN
ncccciPN
nNfP))1(1($)1(($
)$($)1(
),(