Frailty and respiratory impairment in older persons

Abstract

Background: Among older persons, the association between frailty and spirometry-confirmed respiratory impairment has not been evaluated yet.

Methods: By using data on white participants aged 65 to 80 years (Cardiovascular Health Study, N=3578), we evaluated cross-sectional and longitudinal associations between frailty and respiratory impairment, including their combined effect on mortality. Baseline assessments included frailty status (Fried phenotype: non-frail, pre-frail, and frail) and spirometry. Outcomes included development of frailty features (pre-frail or frail) at year 3 and respiratory impairment (airflow limitation or restrictive pattern) at year 4, and death (median follow-up, 13.2 years).

Results: At baseline, 48.3% of participants were pre-frail, 5.8% of participants were frail, 13.8% of participants had airflow limitation, and 9.3% of participants had restrictive pattern; 46.1% of participants subsequently died. At baseline, pre-frail and frail were cross-sectionally associated with airflow limitation (adjusted odds ratio [OR], 1.62; 95% confidence interval [CI], 1.29-2.04 and adjusted OR 1.88; 95% CI, 1.15-3.09) and restrictive pattern (adjusted OR, 1.80; 95% CI, 1.37-2.36 and adjusted OR, 3.05; 95% CI, 1.91-4.88), respectively. Longitudinally, participants with baseline frailty features had an increased likelihood of developing respiratory impairment (adjusted OR, 1.42; 95% CI, 1.11-1.82). Conversely, participants with baseline respiratory impairment had an increased likelihood of developing frailty features (adjusted OR, 1.58; 95% CI, 1.17-2.13). Mortality was highest among participants who were frail and had respiratory impairment (adjusted hazard ratio, 3.91; 95% CI, 2.93-5.22), compared with those who were non-frail and had no respiratory impairment.

Conclusion: Frailty and respiratory impairment are strongly associated with one another and substantially increase the risk of death when both are present. Establishing these associations may inform interventions designed to reverse or prevent the progression of either condition and to reduce adverse outcomes.

Figure 1

Adjusted hazard ratios (95% confidence interval) for all-cause mortality, according to baseline frailty status and respiratory impairment (N = 3,471) a ^a Single Cox regression model, adjusted for age, height, gender, smoking history, BMI, BMI₂, health status, and chronic conditions. The reference group included non-frail participants who had normal pulmonary function. There was a significant interaction between frailty and respiratory impairment (p=.037). The sample size of each subgroup is provided in Table 5.