Using grip strength to compute physical health-adjusted old age dependency ratios

Area of Science:

• Gerontology
• Public Health
• Sociology

Background:

• Conventional old-age dependency ratios (OADR) fail to account for health and functional capacity differences across populations.
• These differences are crucial for understanding labor force participation and broader dependency.
• Existing OADR metrics may misrepresent the true challenges of aging populations worldwide.

Purpose of the Study:

• To investigate the impact of incorporating physical health, specifically hand-grip strength, into OADR calculations.
• To propose and compute a novel, grip-strength-adjusted OADR measure.
• To re-evaluate country rankings and the perceived challenges of population aging by accounting for health disparities.

Main Methods:

• Utilized hand-grip strength as an objective indicator of muscle function, morbidity, disability, and mortality risk.
• Calculated a new OADR measure adjusted for population-level differences in hand-grip strength.
• Compared country rankings based on conventional OADR with rankings derived from the adjusted OADR.

Main Results:

• Adjusting OADR for hand-grip strength led to significant shifts in international country rankings.
• Estimated OADRs generally increased for low- and middle-income countries compared to the age-only OADR.
• Estimated OADRs substantially decreased for high-income countries relative to the conventional OADR.

Conclusions:

• Population aging presents significant challenges not only in high-income countries but also in developing economies.
• Grip-strength-adjusted OADRs provide a more accurate assessment of aging-related challenges by integrating health status.
• This adjusted metric highlights the critical role of functional capacity in dependency and productivity, especially in lower-income settings.