, a prospective cohort study of community-dwelling adults has shown.
“Frailty, a widely recognized geriatric syndrome characterized by multidimensional functional decline in bio-psycho-social factors, is associated with functional disability and mortality,” senior author Tze Pin Ng, MD, National University of Singapore, and colleagues explain.“Our results ... suggest that beyond traditional prognostic markers such as FEV1% (forced expiratory volume in 1 second) and dyspnea, the physical frailty phenotype provides additional useful prognostic information on future risks of disability and mortality,” the authors suggest.
The study was published online Dec. 12 in the journal CHEST®.
SLAS-1 and SLAS-2
Data from the Singapore Longitudinal Ageing Study (SLAS-1) and SLAS-2 were collected and analyzed. SLAS-1 recruited 2,804 participants 55 years of age and older from Sept. 2003 through Dec. 2004, while SLAS-2 recruited 3,270 participants of the same age between March 2009 and June 2013. “Follow-up visits and assessments were conducted approximately 3-5 years apart,” the investigators noted.
Mortality was determined at a mean of 9.5 years of follow-up for SLAS-1 participants and a mean of 6.5 years’ follow-up for SLAS-2 participants. A total of 4,627 participants were eventually included in the analysis, of whom 1,162 patients had COPD and 3,465 patients did not. COPD was classified as mild if FEV1% was greater than or equal to 80%; moderate if FEV1% was greater than or equal to 50% to less than 80%, and severe if FEV1% was less than 50%.
Frailty in turn was based on five clinical criteria, including weakness, slowness, low physical activity, exhaustion, and shrinking. Participants were classified as frail if they met three or more of these criteria and prefrail if they met one or two criteria.
Adverse health outcomes were judged on the basis of instrumental or basic activities of daily living (IADL/ADL), while disability was judged by self-reported difficulties in or requiring assistance with at least one IADL or ADL.
Frail or prefrail
Almost half of the participants were frail or prefrail, as the authors reported, while 25% had COPD. Among the participants with COPD, 30% had moderate to severe COPD, 6.4% had dyspnea, and almost half had prefrailty, while approximately 7% were classified as frail.
This percentage was 86% higher than it was for participants without COPD, among whom just 3.2% were assessed as frail, at an odds ratio of 1.86 (95% CI, 1.35-2.56). Further adjustments for possible confounders reduced the gap between frail COPD and frail non-COPD participants, but frailty remained significantly associated with COPD, at an OR of 1.61 (95% CI, 1.15-2.26), the investigators note.
Furthermore, compared to those without COPD, a diagnosis of COPD without and with dyspnea was associated with a 1.5- and 4.2-fold increase in prevalent frailty (95% CI, 1.04-2.08; 1.84-9.19), respectively, although not with prefrailty. Again, adjusting for multiple confounders, FEV1%, dyspnea, and both prefrailty and frailty were associated with an approximately twofold higher prevalence of IADL/ADL disability, while the prevalence of IADL/ADL disability for participants with COPD was approximately fourfold higher in those with co-occurring FEV1% less than 80% with either prefrailty, frailty, or dyspnea.
Furthermore, the presence of prefrailty or frailty in combination with a lower FEV1% or dyspnea was associated with a 3.7- to 3.8-fold increased risk of having an IADL or ADL disability.