Identifying priority diseases and injuries to promote equality as measured by health-adjusted life expectancy: a population-based study.

STUDY OBJECTIVE: Promoting healthy lifespan equity is a pivotal challenge in the global wave of population ageing, aiming to enable the majority of people in today's long-lived societies to reach a similar age in good health. This study aims to develop a systematic analytical framework to identify age-specific priority diseases and injuries for intervention, thereby comprehensively improving healthy lifespan equity measured by health-adjusted life expectancy (HALE, the average number of years a person can expect to live in full health). METHODS: First, we quantify the contribution of reducing the disease burden at each age to changes in overall HALE and healthy lifespan equity. Then, we decompose these contributions into portions attributable to mortality versus disability, ensuring no residual. Finally, we combine these weights with measures of the stability and relative importance of various causes to produce a list of priority causes for intervention across the entire life course. RESULTS: Globally, the age-specific leading causes where mortality prevention shall be a priority to achieve healthy lifespan equity are enlisted as follows: neonatal disorders (0 years), malaria (1-4 years), drowning (5-9 years), road injuries (10-24 years), HIV/AIDS (25-44 years) and ischaemic heart disease (45-84 years and over 85 years). The age-specific leading causes of disability in need of prioritisation regarding health lifespan equity are as follows: dietary iron deficiency (0-9 years), headache disorders (10-34 years), low back pain (35-69 years), age-related and other hearing loss (70-84 years) and Alzheimer's disease and other dementias (over 85 years). Notably, the specific ranking and relative importance of these causes varied substantially by region and sex, underscoring the need for context-specific strategies. DISCUSSION: Our comprehensive framework can inform policy-makers of whether resources need to be reallocated to meet the healthy lifespan equity challenges in an ageing era.