Ideal Cardiovascular Health and the Compression of Morbidity Among Women of the WHI

Norrina Allen, Ph.D., M.P.H. Department of Preventive Medicine, Northwestern University, Feinberg School of Medicine

Background

• Individuals at “low risk” have lower…..- morbidity- mortality rates- healthcare costs

• These findings have led to the development of the AHA concept of ideal CV health and the 2020 goals

• Currently between 5-7.5% of US adults are in ideal CV health

Unanswered Questions Remain

•While we know ideal CV health delays the onset of CVD and increases longevity, it remains unclear if other diseases simply “replace” CVD resulting in a lengthening of end-of-life morbidity and more expensive healthcare costs or whether ideal CV health results in a compression of morbidity

Significance

“it should be recognized that, although prevention will delay or even prevent the onset of CVD and the cost of cardiovascular treatment,66 patients will need medical care longer and the lifetime cost of care may not be reduced as patients live longer. Thus prevention strategies should not be evaluated solely on their ability to reduce cost of care, but instead they should be valued based on a combination of cost and impact on patient well-being, including length and quality of life.”

- Forecasting the Future of Cardiovascular Disease in the United States: A Policy Statement from the AHA. Heidenreich et al. Circ. 2011;123:938.

Compression of Morbidity

• Fries JF. Aging, Natural Death, and the Compression of Morbidity. NEJM. 1980;303:130-135- Postponement of chronic illness can extend healthy life and

compress the period of senescence/morbidity near the end of life

- If the average age of chronic illness increases faster than the average lifespan then you have compression of morbidity into a smaller proportion of lifespan

Possible Scenarios

Morbidity Death

Present morbidity

55 76

I. Life Extension

55 80

II. Shift to the Right

60 80

III. Compression of Morbidity

65 78

All Optimal

Not All Optimal

Elevated

1 RF

>=2 RF

All Optimal

Not All Optimal

Elevated

1 RF

>=2 RF

All Optimal

Not All Optimal

Elevated

1 RF

>=2 RF

All Optimal

Not All Optimal

Elevated

1 RF

>=2 RF

0 5 10 15 20 25 30 35 40 45 50

CVD Free Survival Time (Years)

Survival after CVD Event (Years)

Figure 2A: CVD-Free Survival and Survival After CVD Event for Men by Risk Factor Burden Index Age (y)

45

55

65

75

Figure from Wilkins, Ning, Berry, Zhao, Dyer, Lloyd-Jones. Lifetime risk for Total Cardiovascular Disease: The Cardiovascular Lifetime Risk Pooling Project. JAMA. 2013.

Overall Aim/Hypothesis

The general goal of this proposal is to understand how favorable CV health may achieve the goal of prolonging the period of healthy life and reducing the time spent with CV morbidity thereby lowering health care costs

Footnote, Presentation or Section Title 10

Specific Aims

1. To determine whether ideal cardiovascular health at baseline is associated with the compression of CVD morbidity into a shorter period of time before death and/or lower average level of CVD morbidity in older ageH1. Ideal CV health at baseline is associated with a greater proportion of life free of CVD morbidity and will have lower average levels of CVD morbidity in older age.H2. Ideal CV health at baseline is associated with unique trajectories of CVD morbidity in older age and lower cumulative CVD morbidity.

2. To determine whether ideal cardiovascular health at baseline is associated with the compression of morbidity into a shorter period of time before death and/or lower average level of morbidity (from all major chronic diseases) in older ageH1. Ideal CV health at baseline will be associated with a greater proportion of life free of all-cause morbidity and will have lower average levels of all-cause morbidity in older age.H2. Ideal CV health at baseline is associated with unique trajectories of all-cause morbidity in older age and lower cumulative morbidity.

3. To determine whether ideal cardiovascular health at baseline is associated with lower cumulative, annual, and end of life Medicare expenditures.H1. Ideal CV health at baseline is associated with lower cumulative, annual and end-of-life health care costs.

Overview of Study Design

• Sample:- observational cohort and clinical trial participants- free of cardiovascular disease at baseline

• Exposure:- Cardiovascular health score at baseline defined according to Ideal CV health

definitions

• Outcomes:- CVD morbidity (defined primarily from CMS)- All Cause Morbidity (defined primarily from CMS)- Mortality (All Cause and CVD)- Healthcare Costs (cumulative, annual and end-of-life costs)

Ideal Health Score

• Ideal Health Score– Created Ideal Health score range 0-14– Sum of individual scores from 7 risk factors and behaviors where poor=0,

intermediate=1 and ideal=2 – Participants will be categorized into poor (0-7), intermediate (8-10), or ideal (11-14)

levels of CV health

Metrics: Health Behaviors

Metric Poor (Score = 0)

Intermediate(Score = 1)

Ideal(Score = 2)

Smoking Current smoker Quit <12 mo. Never or quit >12 mo.

Diet Diet score = 0-1 Diet score = 2-3 Diet score = 4-5

Leisure-Time Physical Activity

No physical activity 1-149 min/wk moderate or 1-74 min/wk vigorous

> 150 min/wk moderate or > 75 min/wk vigorous

Body Weight BMI > 30 kg/m2 BMI = 25-29.9 kg/m2 BMI < 25 kg/m2

Lloyd-Jones et al. Circulation 2010;121(4):586-613

Metrics: Health Factors

Metric Poor(Score = 0)

Intermediate(Score = 1)

Ideal(Score = 2)

Glucose FPG > 126 mg/dl or DM w/ HbA1c >7%

FPG = 100-125 mg/dl or DM w/ HbA1c <7%

FPG <100 mg/dl

Cholesterol TC>240 mg/dl or treated TC>200 mg/dl

TC = 200-239 mg/dl or treated TC <200 mg/dl

TC < 200 mg/dl

Blood Pressure Treated BP >140/>90 or untreated >140/>90 mmHg

SBP = 120-139 or DBP = 80-89, or treated <140/<90 mmHg

BP <120/<80 mmHg

Lloyd-Jones et al. Circulation 2010;121(4):586-613

Morbidity Scores

• CVD Morbidity- defined as the sum of 4 cardiovascular diseases including coronary heart disease

(includes Myocardial infarction), peripheral vascular disease, cerebrovascular disease and chronic heart failure.

- The score can range from 0-4.

• All Cause Morbidity- We will examine two measures of all cause morbidity, one from the questionnaire data

and another derived from the Medicare data. - Gagne comorbidity score, (a well validated comorbidity score designed specifically for

use with administrative (i.e. CMS) data and based on ICD-9 discharge diagnosis codes.)

- We will adapt the Gagne score to the questionnaire data collected from the WHI participants (using similar methods to those of Gold et al. 2006) as well as calculate it using the Medicare data

- Calculated for each year of age where CMS data is available

Healthcare Costs

• Calculated using CMS claims data• Measures include:

- Average annual healthcare costs- Cumulative healthcare costs- End-of-life costs

• 2010 CMS DRG payment level will be applied to all hospital and outpatient encounters, to obtain a measure of cost which is adjusted for inflation and independent of regional and institutional variations in reimbursement rates and cost to charge ratios• apply 2010 national DRG weights and Relative Value Scale (RVS) weights to hospital

inpatient and relevant part B utilization data to obtain costs

Overview of Methods for Aims 1 and 2

• examine potential differences by CV health score in both mean major morbidity-free survival time and mean overall survival time. - Morbidity-free survival will be defined as the years alive prior to the

onset of CV morbidity or all-cause morbidity• Is Ideal CV Health Associated with Lower Average Levels of Morbidity?

- In order to answer this question, we will test whether individuals with ideal CV health score will have lower average levels of all-cause and CV morbidity using linear mixed effects models

• Examine trajectories in morbidity by CV health score

Overview of Methods for Aim 3

• We will use a mixed effects model to determine whether individuals in ideal CV health have lower health care costs- Adjust for “induced censoring”- End-of-life costs will only include participants who had died during

follow-up• a joint model of longitudinal (annual) medical costs and survival to study the

association between medical costs and mortality- derive incremental cost-effectiveness ratio (ICER) defined as the ratio of

the difference in costs to the difference in outcomes (years of life or quality adjusted years of life) for the 4 CV health profiles under study.

Wilkins, Ning, Berry, Zhao, Dyer, Lloyd-Jones. Lifetime risk for Total Cardiovascular Disease: The Cardiovascular Lifetime Risk Pooling Project. Under Review

Significance

• The AHA and other public health organizations have made it their goal to increase the number of Americans in ideal CV health; however, the impact that it may have on the future burden of morbidity, mortality and healthcare costs remains unknown.

• Should our study hypothesis prove true, they provide added motivation for both individuals and society to improve cardiovascular health.

• In addition, policy makers will have concrete estimates of healthcare costs upon which to base cost-effectiveness evaluations and funding priorities.• • If as some might argue, improving health does not compress morbidity rather it

simply extends the period of life lived with disease, then our findings will identify the need for further research to understand predictors of healthy aging as compared to those that simply prolong life.

Wilkins, Ning, Berry, Zhao, Dyer, Lloyd-Jones. Lifetime risk for Total Cardiovascular Disease: The Cardiovascular Lifetime Risk Pooling Project. Under Review

Thank You