Quantifying the impact of modifiable risk factors on frailty: A population-attributable fraction analysis in older adults.

Lower educational attainment was the strongest single contributor to incident frailty at the population level, accounting for 19.9% of cases.

• Educational attainment was treated as a life-course socioeconomic indicator.
• Population-attributable fraction (PAF) for lower educational attainment was 19.9%.
• This was the largest PAF among all risk factors examined.
• Associations were examined using Cox proportional hazards models with age as the time scale, adjusting for sex.

Lack of regular exercise was the second largest modifiable contributor to incident frailty, with a population-attributable fraction of 14.2%.

• PAF for lack of regular exercise was 14.2%.
• This was a lifestyle behavioral factor measured at baseline reflecting current or later-life status.
• It was the largest lifestyle behavioral contributor among those analyzed.

Current smoking contributed 9.8% of the population-attributable fraction for incident frailty.

• PAF for current smoking was 9.8%.
• Smoking was classified as a lifestyle behavior measured at baseline.
• It was statistically significant in the multivariable Cox proportional hazards model.

Diabetes mellitus accounted for 8.0% of the frailty burden at the population level.

• PAF for diabetes mellitus was 8.0%.
• Diabetes was classified as a clinical factor measured at baseline.
• It was statistically significant in the multivariable model.

Falls, cognitive impairment, arthritis, and stroke each contributed meaningfully to population-level frailty incidence.

• PAF for falls was 7.0%.
• PAF for cognitive impairment was 5.6%.
• PAF for arthritis was 4.9%.
• PAF for stroke was 3.6%.
• All were classified as clinical factors and were statistically significant in the multivariable Cox proportional hazards model.

The eight identified modifiable risk factors together accounted for approximately 51.6% of the incident frailty burden in the study population.

• The combined PAF of all eight significant risk factors was approximately 51.6%.
• Risk factors included lower educational attainment, lack of regular exercise, current smoking, diabetes mellitus, falls, cognitive impairment, arthritis, and stroke.
• PAFs were calculated only for risk factors that were statistically significant in the multivariable model.

The analytical sample comprised 5334 community-dwelling older adults with 509 incident frailty cases occurring during follow-up.

• Sample size was 5334 participants with a mean age of approximately 69 years; 47% were men.
• Data came from the Healthy Aging Longitudinal Study in Taiwan (HALST), a nationwide cohort of community-dwelling adults aged 55 years and over.
• Frailty was defined using the Fried frailty phenotype; participants with baseline frailty were excluded.
• 509 incident cases of frailty occurred during follow-up.