Minimum income for healthy living and frailty in adults over 65 years old in the English Longitudinal Study of Ageing: a population-based cohort study

Abstract

ObjectiveTo test whether minimum income for healthy living of a person aged 65 years or older (MIHL65) is associated with frailty in older adults.Design and settingSecondary analysis of the English Longitudinal Study of Ageing, a multiwave prospective cohort study in England, UK.ParticipantsA subset (n=1342) of English Longitudinal Study of Ageing participants, who at wave 1 in 2002 were aged 65 years or older, without any limiting long-standing illnesses, and who had the information required to calculate MIHL65in 2002, 2004 and 2006 and two measures of frailty in 2008.Main outcome measuresFrailty defined using Fried’s phenotype criteria and Rockwood’s Index of deficits.ResultsThe odds of frailty in 2008 were significantly higher for participants living below MIHL65in 2002, both on Fried’s phenotype criteria (OR 2.56, 95% CI 1.57 to 4.19) and Rockwood’s Index (OR 2.83, 95% CI 1.74 to 4.60). These associations remained after adjustment for age and gender for both Fried’s phenotype (OR 1.85, 95% CI 1.18 to 2.90) and Rockwood’s Index (OR 2.15, 95% CI 1.38 to 3.35). Compared with those whose income during 2002–2006 was always above MIHL65, the odds of frailty in 2008 for those below MIHL65were two-to-three times higher, with a tendency for the ORs to increase in line with the length of time spent below MIHL65(ORs (95% CIs) were: Fried’s phenotype, below MIHL65once: 2.02 (1.23 to 3.34); twice: 2.52 (1.37 to 4.62); thrice: 3.53 (1.65 to 7.55). Rockwood’s Index: once: 2.34 (1.41 to 3.86); twice: 3.06 (1.64 to 5.71); thrice: 2.56 (1.22 to 5.34)). These associations remained after adjustment for age and gender on Rockwood’s Index, but not Fried’s phenotype.ConclusionsThese results provide some support for the idea that frailty at older ages is associated with not having sufficient income to lead a healthy life.