Longitudinal changes in comorbidity patterns over time in relation to mortality in older Korean adults

Area of Science:

• Gerontology
• Public Health
• Epidemiology

Background:

• Comorbidity significantly impacts health outcomes in older adults.
• Understanding comorbidity trajectories is essential for geriatric care and mortality prediction.
• The National Health Insurance Service-Korean Senior (NHIS-Korean Senior) database provides valuable insights into elderly health in South Korea.

Purpose of the Study:

• To investigate patterns of comorbidity change over time in South Korean older adults.
• To determine the effect of different comorbidity trajectories on mortality risk.
• To identify specific comorbidity patterns associated with increased mortality in the elderly.

Main Methods:

• Utilized the NHIS-Korean Senior claim database (10% random sample) of adults aged 60+.
• Analyzed 121,733 subjects hospitalized at least annually between 2002 and 2008.
• Employed Growth Mixture Modeling (GMM) and Cox proportional hazards models to assess comorbidity trajectories and mortality rates (1, 3, and 5-year).

Main Results:

• Identified five distinct comorbidity trajectory groups: consistently low, increased, decreased/low, decreased/high, and consistently high.
• The consistently high comorbidity group exhibited the highest mortality risk across all follow-up periods (1, 3, and 5 years).
• Hazard Ratios (HR) for the consistently high group were 3.48 (1-year), 2.53 (3-year), and 1.92 (5-year) compared to the decreased/low group, after adjusting for confounders.

Conclusions:

• Five distinct comorbidity trajectories significantly predict varying risks of mortality in older adults.
• Consistently high comorbidity is a strong predictor of increased mortality risk in the elderly population.
• Monitoring comorbidity changes over time is vital for risk stratification and intervention in geriatric care.