|Vaz Fragoso, Carlos - Yale University|
|Hsu, Fang-chi - Wake Forest University|
|Brinkley, Tina - Wake Forest University|
|Church, Timothy - Pennington Biomedical Research Center|
|Liu, Christine - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
|Manini, Todd - University Of Florida|
|Newman, Anne - University Of Pittsburgh|
|Stafford, Randall - Stanford University|
|Mcdermott, Mary - Northwestern University|
|Gill, Thomas - Yale University|
Submitted to: Journal of the American Medical Directors Association - Post-Acute and Long Term Care Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/2/2014
Publication Date: 9/1/2014
Citation: Vaz Fragoso, C.A., Hsu, F., Brinkley, T., Church, T., Liu, C., Manini, T., Newman, A.B., Stafford, R.S., McDermott, M.M., Gill, T.M. 2014. Combined reduced forced expiratory volume in 1 second (FEV1) and peripheral artery disease in sedentary elders with functional limitations. Journal of the American Medical Directors Association - Post-Acute and Long Term Care Medicine. 15(9):665-670. https://doi.org/10.1016/j.jamda.2014.05.008.
Interpretive Summary: Many older adults have limited lung function, either due to disease or environmental factors, such as cigarette exposure. Many older adults also have peripheral artery disease, or reduced blood flow to the legs. Using data from a study of older adults, this study found that 6% of the study participants had both conditions. The study found that persons with both conditions were more likely to walk slowly (less than 0.8 meters/second). The study investigators thought that having both limited lung function and PAD might reduce people's endurance for walking long distances. Because of this poor endurance, these persons walked slower. This study finding is important because other studies have found that walking slowly has been found to be associated with increased risk of death.
Technical Abstract: Objectives: Because they are potentially modifiable and may coexist, we evaluated the combined occurrence of a reduced forced expiratory volume in 1-second (FEV1) and peripheral artery disease (PAD), including its association with exertional symptoms, physical inactivity, and impaired mobility, in sedentary elders with functional limitations. Design: Cross-sectional. Setting: Lifestyle Interventions and Independence in Elder (LIFE) Study. Participants: 1307 sedentary community-dwelling persons, mean age 78.9, with functional limitations (Short Physical Performance Battery [SPPB] <10). Measurements: A reduced FEV1 was defined by a z-score <-1.64 (< lower limit of normal), while PAD was defined by an ankle-brachial index <1.00. Exertional dyspnea was defined as moderate-to-severe (modified Borg index), immediately after a 400-meter walk test (400MWT). Exertional leg symptoms were established by the San Diego Claudication Questionnaire. Physical inactivity was evaluated by percent of accelerometry wear-time with activity less than 100 counts/min (top quartile established high sedentary-time). Mobility was evaluated by the 400MWT (gait-speed <0.8 m/s defined as slow) and SPPB (= 7 defined moderate-to-severe mobility impairment). Results: A combined reduced FEV1 and PAD was established in 6.0% (78/1307) of participants. However, among those who had a reduced FEV1, 34.2% (78/228) also had PAD, while 20.8% (78/375) of those who had PAD also had a reduced FEV1. The two combined conditions were associated with exertional dyspnea (adjusted odds ratio [adjOR] 2.59 [1.20, 5.60]) and slow gait speed (adjOR 3.15 [1.72, 5.75]) but not with exertional leg symptoms, high sedentary time, and moderate-to-severe mobility impairment. Conclusions: In sedentary community-dwelling elders with functional limitations, a reduced FEV1 and PAD frequently coexisted and, in combination, were strongly associated with exertional dyspnea and slow gait-speed (a frailty indicator that increases the risk of deleterious outcomes).