Evidence of functional declining and global comorbidity measured at baseline proved to be the strongest predictors for long-term death in elderly community residents aged 85 years: a 5-year follow-up evaluation, the OCTABAIX study

Abstract

Objective

To investigate the predictive value of functional impairment, chronic conditions, and laboratory biomarkers of aging for predicting 5-year mortality in the elderly aged 85 years.

Methods

Predictive value for mortality of different geriatric assessments carried out during the OCTABAIX study was evaluated after 5 years of follow-up in 328 subjects aged 85 years. Measurements included assessment of functional status comorbidity, along with laboratory tests on vitamin D, cholesterol, CD4/CD8 ratio, hemoglobin, and serum thyrotropin.

Results

Overall, the mortality rate after 5 years of follow-up was 42.07%. Bivariate analysis showed that patients who survived were predominantly female (P=0.02), and they showed a significantly better baseline functional status for both basic (P<0.001) and instrumental (P<0.001) activities of daily living (Barthel and Lawton index), better cognitive performance (Spanish version of the Mini-Mental State Examination) (P<0.001), lower comorbidity conditions (Charlson) (P<0.001), lower nutritional risk (Mini Nutritional Assessment) (P<0.001), lower risk of falls (Tinetti gait scale) (P<0.001), less percentage of heart failure (P=0.03) and chronic obstructive pulmonary disease (P=0.03), and took less chronic prescription drugs (P=0.002) than nonsurvivors. Multivariate Cox regression analysis identified a decreased score in the Lawton index (hazard ratio 0.86, 95% confidence interval: 0.78–0.91) and higher comorbidity conditions (hazard ratio 1.20, 95% confidence interval: 1.08–1.33) as independent predictors of mortality at 5 years in the studied population.

Conclusion

The ability to perform instrumental activities of daily living and the global comorbidity assessed at baseline were the predictors of death, identified in our 85-year-old community-dwelling subjects after 5 years of follow-up.

Keywords:

• oldest old
• mortality
• comorbidity
• instrumental activity of daily living

Acknowledgments

Members of the OCTABAIX Study: J Almeda (Unitat de Suport a la Recerca de Costa de Ponent, IDIAP J Gol), T Badia (ABS Martorell Urbano), A Lobato (ABS Sant Andreu de la Barca), C Fernández (CAP Rambla), A Ferrer (CAP El Pla), F Formiga (UFISS de Geriatría, Servicio de Medicina Interna, Hospital Universitari de Bellvitge), A Gil (ABS Sant Andreu de la Barca), MJ Megido (ABS Just Oliveras), G Padrós (Laboratori Clínic L’Hospitalet), M Sarró (CAP Florida Nord), and A Tobella (ABS Martorell Rural)

Disclosure

The authors report no conflicts of interest in this work.