J Nutr Health Aging
THE JOURNAL OF NUTRITION, HEALTH & AGING©
INTAKE OF ANTIOXIDANTS AND SUBSEQUENT DECLINE IN PHYSICAL FUNCTION IN A RACIALLY/ETHNICALLY DIVERSE POPULATION B. BARTALI1, T. CURTO1, N.N. MASEREJIAN1, A.B. ARAUJO1 1. Department of Epidemiology, New England Research Institutes, Inc., 9 Galen Street, Watertown, MA 02472, USA. Corresponding author: B. Bartali, Senior Research Scientist, [email protected]; Office Tel: +1 617972 3350
Abstract: Objectives: Oxidative stress is considered a risk factor for physical function (PF) decline with aging. The objective of this study was to examine the relationship between antioxidant intake and change in PF over a 5-year period. Design, Setting, Participants: The Boston Area Community Health (BACH) Survey is a population-based longitudinal study including 5,502 racially/ethnically diverse and randomly selected participants aged 30-79 years. Measurements: In total, 2828 persons aged 30-79 years completed the validated Block Food Frequency Questionnaire (FFQ) and participated in the follow-up study. Change in PF from baseline (2002-2005) to follow-up (2006-2010) was assessed using the validated SF-12 questionnaire. Linear models were used to examine the association between energy-adjusted quartiles of vitamins C, E and carotenoids and change in PF. Results: A low intake (first quartile) of vitamin E was associated with a greater decline in PF compared with the highest quartile, with a mean difference in change in PF of -1.73 (95%CI:-3.31,-0.15). Notably, this mean difference was clinically meaningful as it was equivalent to the effect estimate we found for participants who were approximately 15 years apart in age in our cohort, as 1 year increase in age was associated with a mean difference in change in PF of -0.11 (95%CI:-0.16,-0.06). PF decline was not significantly different in the lowest compared with the highest quartile of vitamin C (mean difference=-1.29, 95%CI:-2.61, 0.03) or carotenoids (mean difference=-0.62, 95%CI:-2.22,0.99). Conclusions: Low intake of vitamin E was significantly associated with decline in PF with aging. These results are clinically meaningful, extend previous findings that oxidative stress contributes to PF decline, and may inform the development of future prevention strategies aimed at reducing this clinical and public health problem. Key words: BACH, antioxidants, vitamin E, physical function, Block food frequency questionnaire.
Introduction Decline in physical function and mobility limitations are major risk factors for the development of disability and dependence with aging (1-4) and have an important impact on health care costs and quality of life of older persons and their families (5). Indeed, persons with mobility difficulties and disabilities are more likely to experience poorer health compared to their nondisabled counterparts, resulting in the need for assistance and increased medical costs (5). Consequently, the identification of potentially modifiable factors, such as nutrition, that may help to prevent or reduce the development of these adverse outcomes represents an important avenue of investigation from a clinical and public health perspective. Our prior studies (6-9) have demonstrated a role of nutrition in decline in physical function, with antioxidants playing a central role. We showed that a low dietary intake/concentration of antioxidants is associated with reduced muscle strength (6), frailty (7), decline in physical function (8) and the development of disability (9), suggesting that antioxidants exert an independent effect on functional outcomes. Indeed, oxidative stress is a putative factor contributing to muscle damage (10, 11) and functional decline (12) and a low level of antioxidants may tip the balance between oxidants and antioxidants, allowing for oxidative stress. However, these previous studies have been limited by their cross-sectional Received April 28, 2014 Accepted for publication August 7, 2014
1
design (7, 13) and/or the inclusion of specific populations, such as only older women with some level of mobility limitations or only Caucasians (6-9). Because sex and racial differences exist in both dietary intake and musculoskeletal health (14, 15), the objective of this study was to determine whether low antioxidant intake is associated with subsequent decline in physical function in a racially/ethnically diverse US population of men and women, and to examine whether this relationship differs by race/ethnicity and other sociodemographic characteristics. To address these objectives, we used data from the Boston Area Community Health (BACH) Survey, a large population-based longitudinal study of racially/ethnically diverse US population. Methods Data were obtained from a longitudinal cohort study of men and women, the BACH Survey. BACH recruited a random sample of 5,502 residents (2,301 men, 3,201 women) aged 30-79 years from three racial/ethnic groups in Boston, MA. Subjects completed an in-person interview at baseline (20022005) and approximately 5 years later (2006-2010). At both time points, a home visit was conducted to collect information including sociodemographic characteristics, anthropometric measures (e.g., height, weight, and waist circumference), comorbidities and lifestyle factors. Further details on methods have been previously published (16, 17). All subjects provided
J Nutr Health Aging
INTAKE OF ANTIOXIDANTS AND SUBSEQUENT DECLINE IN PHYSICAL FUNCTION IN A RACIALLY/ETHNICALLY written informed consent. The study was approved by the New England Research Institutes’ Institutional Review Board. As specified in Figure 1, in total 4,144 persons (1,610 men; 2,534 women) completed follow-up interviews, with an overall conditional response rate of 80.5%. The mean (SD) time to follow-up was 4.8 (0.6) years. Of those lost to follow-up, 654 people were unable to be reached, 350 refused to participate, and 349 were ineligible (deceased, pregnant/post-partum
THE JOURNAL OF NUTRITION, HEALTH & AGING©
INTAKE OF ANTIOXIDANTS AND SUBSEQUENT DECLINE IN PHYSICAL FUNCTION IN A RACIALLY/ETHNICALLY DIVERSE POPULATION B. BARTALI1, T. CURTO1, N.N. MASEREJIAN1, A.B. ARAUJO1 1. Department of Epidemiology, New England Research Institutes, Inc., 9 Galen Street, Watertown, MA 02472, USA. Corresponding author: B. Bartali, Senior Research Scientist, [email protected]; Office Tel: +1 617972 3350
Abstract: Objectives: Oxidative stress is considered a risk factor for physical function (PF) decline with aging. The objective of this study was to examine the relationship between antioxidant intake and change in PF over a 5-year period. Design, Setting, Participants: The Boston Area Community Health (BACH) Survey is a population-based longitudinal study including 5,502 racially/ethnically diverse and randomly selected participants aged 30-79 years. Measurements: In total, 2828 persons aged 30-79 years completed the validated Block Food Frequency Questionnaire (FFQ) and participated in the follow-up study. Change in PF from baseline (2002-2005) to follow-up (2006-2010) was assessed using the validated SF-12 questionnaire. Linear models were used to examine the association between energy-adjusted quartiles of vitamins C, E and carotenoids and change in PF. Results: A low intake (first quartile) of vitamin E was associated with a greater decline in PF compared with the highest quartile, with a mean difference in change in PF of -1.73 (95%CI:-3.31,-0.15). Notably, this mean difference was clinically meaningful as it was equivalent to the effect estimate we found for participants who were approximately 15 years apart in age in our cohort, as 1 year increase in age was associated with a mean difference in change in PF of -0.11 (95%CI:-0.16,-0.06). PF decline was not significantly different in the lowest compared with the highest quartile of vitamin C (mean difference=-1.29, 95%CI:-2.61, 0.03) or carotenoids (mean difference=-0.62, 95%CI:-2.22,0.99). Conclusions: Low intake of vitamin E was significantly associated with decline in PF with aging. These results are clinically meaningful, extend previous findings that oxidative stress contributes to PF decline, and may inform the development of future prevention strategies aimed at reducing this clinical and public health problem. Key words: BACH, antioxidants, vitamin E, physical function, Block food frequency questionnaire.
Introduction Decline in physical function and mobility limitations are major risk factors for the development of disability and dependence with aging (1-4) and have an important impact on health care costs and quality of life of older persons and their families (5). Indeed, persons with mobility difficulties and disabilities are more likely to experience poorer health compared to their nondisabled counterparts, resulting in the need for assistance and increased medical costs (5). Consequently, the identification of potentially modifiable factors, such as nutrition, that may help to prevent or reduce the development of these adverse outcomes represents an important avenue of investigation from a clinical and public health perspective. Our prior studies (6-9) have demonstrated a role of nutrition in decline in physical function, with antioxidants playing a central role. We showed that a low dietary intake/concentration of antioxidants is associated with reduced muscle strength (6), frailty (7), decline in physical function (8) and the development of disability (9), suggesting that antioxidants exert an independent effect on functional outcomes. Indeed, oxidative stress is a putative factor contributing to muscle damage (10, 11) and functional decline (12) and a low level of antioxidants may tip the balance between oxidants and antioxidants, allowing for oxidative stress. However, these previous studies have been limited by their cross-sectional Received April 28, 2014 Accepted for publication August 7, 2014
1
design (7, 13) and/or the inclusion of specific populations, such as only older women with some level of mobility limitations or only Caucasians (6-9). Because sex and racial differences exist in both dietary intake and musculoskeletal health (14, 15), the objective of this study was to determine whether low antioxidant intake is associated with subsequent decline in physical function in a racially/ethnically diverse US population of men and women, and to examine whether this relationship differs by race/ethnicity and other sociodemographic characteristics. To address these objectives, we used data from the Boston Area Community Health (BACH) Survey, a large population-based longitudinal study of racially/ethnically diverse US population. Methods Data were obtained from a longitudinal cohort study of men and women, the BACH Survey. BACH recruited a random sample of 5,502 residents (2,301 men, 3,201 women) aged 30-79 years from three racial/ethnic groups in Boston, MA. Subjects completed an in-person interview at baseline (20022005) and approximately 5 years later (2006-2010). At both time points, a home visit was conducted to collect information including sociodemographic characteristics, anthropometric measures (e.g., height, weight, and waist circumference), comorbidities and lifestyle factors. Further details on methods have been previously published (16, 17). All subjects provided
J Nutr Health Aging
INTAKE OF ANTIOXIDANTS AND SUBSEQUENT DECLINE IN PHYSICAL FUNCTION IN A RACIALLY/ETHNICALLY written informed consent. The study was approved by the New England Research Institutes’ Institutional Review Board. As specified in Figure 1, in total 4,144 persons (1,610 men; 2,534 women) completed follow-up interviews, with an overall conditional response rate of 80.5%. The mean (SD) time to follow-up was 4.8 (0.6) years. Of those lost to follow-up, 654 people were unable to be reached, 350 refused to participate, and 349 were ineligible (deceased, pregnant/post-partum
