Estimating Health Adjusted Age at Death (HAAD)

Area of Science:

• Public Health
• Health Economics
• Epidemiology

Background:

• Lifetime health is crucial for assessing individual well-being and population health.
• Existing metrics may not adequately capture health equity across diverse conditions and socioeconomic settings.
• Comparing health outcomes requires a nuanced approach that considers the full spectrum of life with a condition.

Purpose of the Study:

• To introduce and validate the Health Adjusted Age at Death (HAAD) metric for equity-relevant health comparisons.
• To assess and rank the impact of four specific medical conditions (AML, ALL, schizophrenia, epilepsy) on lifetime health across six countries.
• To provide a framework for incorporating health equity into health intervention priority setting.

Main Methods:

• Developed the Health Adjusted Age at Death (HAAD) metric, incorporating past and future expected healthy life years.
• Analyzed data from the 2017 Global Burden of Disease Study for acute myeloid leukemia (AML), acute lymphoid leukemia (ALL), schizophrenia, and epilepsy in Ethiopia, Haiti, China, Mexico, the United States, and Japan.
• Utilized four key measures to assess 'worse off' populations: proportion with HAAD<20 (T20), 25th percentile (Q1), 75th percentile (Q3), and average HAAD (aHAAD).

Main Results:

• HAAD analysis revealed variations in lifetime health outcomes even when average HAAD (aHAAD) was similar between conditions (e.g., AML vs. ALL in the US).
• Significant disparities were observed in lifetime health associated with conditions like epilepsy, with higher Q1 values in high-income countries (Japan) compared to low-income settings (Ethiopia).
• The study demonstrated that different equity measures (T20, Q1, Q3, aHAAD) provide distinct insights into population health distributions.

Conclusions:

• The Health Adjusted Age at Death (HAAD) metric offers a robust tool for evaluating health equity across different medical conditions and geographical regions.
• HAAD facilitates the identification of patient groups experiencing worse lifetime health outcomes.
• Incorporating HAAD-based distribution of lifetime health can inform more equitable health intervention prioritization.