Background:
Deficit accumulation is a well acknowledged approach to determine frailty in older
people. The Activity and Function in the Elderly (ActiFE Ulm) Study is a cohort study
among individuals ≥65 years, which started in 2009. We intended to study whether deficit
accumulation was associated with six-year mortality in community dwelling older adults.
Methods:
A frailty index (FI) was built according to the model proposed by Rockwood. We identified
38 items at baseline representing following domains: basic and instrumental activities
of daily living, comorbidities, number of medications, fall risk, psychosocial anamnesis,
cognitive function, physical activity, fitness and self-awareness. Each variable had
a score from 0 (no deficit) to 1 (presence of deficit). FI represents the sum of all
scores divided by 38. Cox-proportional hazards models evaluated the association of
the estimated FI and six-year mortality stratified by sex, adjusted for age, smoking
and education.
Results:
A total of 948 subjects were considered for this analysis (mean age 75.3 ± 6.3, 57.5%
men). Median FI was 0.11 (interquartile range (IQR) [0.07, 0.17]) in men, and 0.12
(IQR [0.07, 0.19]) in women, 16.2% men and 21.6% women had a FI ≥0.2. We observed
a total of 128 deaths (median FU 2434 days). A 10% increment of FI was associated
with an adjusted hazard ratio (HR) of 2.28 [95% CI 1.79, 2.89] in men and a HR of
1.81 [95% CI 1.40, 2.35] in women for death during six-year follow-up. As categorical,
those with FI ≥0.2 had a HR of 3.40 [95% CI 2.26, 5.11] in men, and a HR of 3.18 [95%
CI 1.59, 6.33] in women.
Conclusions:
Using a deficit accumulation approach for frailty requires a thorough assessment of
older people, which may not be easily accomplished in the clinical settings. In this
relatively healthy population-based cohort, ca. 20% were categorized as frail (FI
≥0.2). FI, both as continuous and categorical measure, was clearly associated with
six-year mortality in men and women.
