Skip to content
PaperFren

Do blood ageing markers predict death better as a bundle than one-by-one?

Open paper intelligence

In 777 Newcastle 85+ participants, a 40-biomarker frailty index predicted 7-year mortality (HR 1.05 per 1% FI-B; AUC 0.66) better than any single marker (AUC ≤0.61); combining with the clinical FI raised AUC to 0.75.

Source

Age-related frailty and its association with biological markers of ageing

Mitnitski A, Collerton J, Martin-Ruiz C, et al. · BMC medicine · 2015

doi.org/10.1186/s12916-015-0400-xRead the full paper ↗224 citationscc by

Study at a glance

Design
Cohort — Newcastle 85+ cohort: baseline biomarker/clinical frailty indices vs up to 7-year mortality.
N
N=845 · 845 enrolled (mean age 85.5); FI-B calculable in 777 (60.9% women).
Population
Very old adults in the Newcastle 85+ Study (UK), mean age 85.5 years.
Outcome
All-cause mortality predicted by a 40-item biomarker frailty index (FI-B) vs clinical FI-CD, Fried phenotype, and single biomarkers.

Structured fields used in claim comparison tables when every cited study has a complete layer.

What they did

Built FI-B from 40 cellular-ageing, inflammation, haematology, and immunosenescence markers, compared it with a clinical deficit FI and the Fried phenotype, and tested 7-year mortality with Cox models, Kaplan–Meier strata, random biomarker subsamples, and ROC AUCs.

What they found

Mean FI-B 0.35 vs FI-CD 0.22; nobody had FI-B <0.12. Each 1% FI-B rise raised HR by 5.4%. FI-B beat every individual biomarker and was robust to dropping items. Combined FI-CD/FI-B AUC was 0.75 vs 0.71 and 0.66 alone.

The limits

What it doesn't show

Moderate AUCs are not bedside tests; FI-B and FI-CD correlated only weakly (r=0.16), so blood markers do not simply duplicate clinical frailty.

Key terms

FI-B
Biomarker frailty index: proportion of 40 laboratory ageing deficits present (mean 0.35).
FI-CD
Clinical-deficits frailty index (mean 0.22) based on health problems, not labs.
Fried phenotype
Classic five-item physical frailty phenotype used as a comparator.
Newcastle 85+ Study
UK cohort of people around age 85; n=845 here with up to 7-year mortality.
Deficit accumulation
Frailty as the ratio of deficits present to deficits counted—applied here to blood markers.

Flashcards

1 / 10

Research intelligence for this paper

See its role on concept claims, tensions it is part of, placement history, and related discoveries.

Open paper intelligence

Quiz yourself

1 / 6

Newcastle 85+ n in the methods was:

Common questions

How old were participants?

Mean 85.5 years; FI-B n=777, 60.9% women.

Mean FI-B vs FI-CD?

0.35 vs 0.22; no one had FI-B <0.12.

Mortality HR per 1% FI-B?

About 1.05 (5.4% higher hazard).

Best discrimination?

Combined FI-CD + FI-B AUC 0.75 for 7-year death.

More on Diagnostic accuracy