Do subclinical vascular abnormalities precede impaired physical ability and ADL disability?

Cardiovascular disease is an important cause of disability in activities of daily living (ADL) through its effect on physical functioning. However, it is unclear whether subclinical vascular abnormalities and rate of change in subclinical vascular abnormalities is also associated with an impaired physical ability and with ADL disability. In a longitudinal study, 490 middle-aged and older persons were included. Physical ability was measured using the Short Physical Performance Battery and ADL disability using a questionnaire on self-reported basic and instrumental ADL. Subclinical vascular abnormalities were measured by pulse wave velocity (PWV) and carotid intima media thickness (CIMT, in men only). Longitudinal associations between baseline markers of subclinical vascular abnormalities, their rate of change, and change in physical ability or ADL disability were assessed using generalized estimation equation models. After adjustment for confounders, higher baseline PWV, change in PWV, baseline CIMT (in men) and change in CIMT (in men) were associated with a higher rate of change in physical ability (regression coefficients 0.035, 95% CI [0.018; 0.052]; 0.047, 95% CI [0.024; 0.069]; 0.214, 95% CI [0.070; 0.358] and 0.148, 95% CI [0.019; 0.277], respectively). No relations were found for change in ADL disability. In subjects with incident cardiovascular disease, higher change in PWV was associated with a higher rate of change in ADL disability (regression coefficient 0.054, 95% CI [0.001; 0.106]). The present study showed that subclinical vascular abnormalities and rate of change were associated with higher rate of change in physical ability. The association between (change in) subclinical vascular abnormalities and ADL disability tended to be stronger in persons with incident and prevalent cardiovascular disease. These data may suggest that ADL decline is more a direct effect of experienced clinically manifest vascular events rather than the effect of progression of subclinical vascular abnormalities.