The relationship between grip strength and muscle mass (MM), inflammatory biomarkers and physical performance in community-dwelling very old persons D. Legrand a, *, W. Adriaensen a,b , B. Vaes a , C. Matheı¨ a,b , P. Wallemacq c , J. Degryse a,b a Institut de Recherche Sante ´ et Societe ´, Universite ´ Catholique de Louvain (UCL), Brussels, Belgium b Department of Primary Health Care, Katholieke Universiteit Leuven (KUL), Leuven, Belgium c Laboratory of Analytical Biochemistry, Cliniques Universitaires St Luc, Universite ´ Catholique de Louvain, Brussels, Belgium 1. Introduction Sarcopenia is defined by a loss of MM and strength with aging (Hughes, Frontera, Roubenoff, Evans, & Singh, 2002; Lexell & Taylor, 1991). The main consequence of the loss of MM and muscle strength is limitations of physical performance, mobility and disability in older people which increases the risk of falls, fractures, hospitalizations, dependency, frailty and mortality (Abellan van Kan, 2009; Janssen, Heymsfield, & Ross, 2002; Rolland et al., 2008). Several studies have shown muscle force is declining faster than the MM (Delmonico et al., 2009; Doherty, 2003; Goodpaster et al., 2006; Miller et al., 2008) in particular in subjects aged 80 years or more (McNeil, Doherty, Stashuk, & Rice, 2005). The MM declines annually approximately 1–2% after 50 years of age but muscle strength declines annually approximately 1–1.5% between 50 and 60 years of age and 3% after 60 years of age (Abellan van Kan, 2009; Bassey & Harries, 1993; Vandervoort, 2002). Furthermore, the age- associated loss of strength (dynapenia) is not completely explained by the loss of MM (Clark & Manini, 2010). Longitudinal studies showed poor hand strength, as measured by handgrip, is a predictor of functional disability (Giampaoli et al., 1999; Rantanen et al., 2001) and mortality (Rantanen et al., 2003). Several studies previously showed that muscle strength and/or physical perfor- mance capacity are better predictors of clinical outcomes than low MM (Cruz-Jentoft et al., 2010; Hairi et al., 2010; Laurentani et al., 2003; McNeil et al., 2005). Many factors have been reported to intervene in the process of decreasing MM, including physical activity, nutritional status, hormonal status and chronic inflammation (Rolland et al., 2008). More specifically, lower MM and lower muscle strength have been associated with higher plasma concentrations of IL-6 and TNF-a in well-functioning older men and women, suggesting higher cytokine levels may contribute to losses of MM and strength (Schaap, Pluijm, Deeg, & Visser, 2006; Schaap et al., 2009; Visser Archives of Gerontology and Geriatrics xxx (2013) xxx–xxx A R T I C L E I N F O Article history: Received 2 October 2012 Received in revised form 23 April 2013 Accepted 2 June 2013 Available online xxx Keywords: Sarcopenia Physical performance Grip strength MM Inflammatory biomarkers A B S T R A C T The main consequence of the loss of MM and muscle strength is limitations of physical performance and disability in older people. It is unclear whether a decline in functional capacity results from the loss of MM and/or the qualitative impairment of the muscle tissue. The aim of our research was to investigate the relationship between physical performance and grip strength, inflammatory markers and MM in a population of community-dwelling very old persons. This study is a cross-sectional analysis within the BELFRAIL-study, a cohort study of subjects aged 80 years and older (n = 567). MM was assessed by bioelectrical impedance. Interleukin-6 (IL-6) and tumor necrosis factor-a (TNF-a) concentrations were determined on fasting blood samples. Logistic regression analysis was build using a low physical performance level evaluated according to Short Physical Performance Battery (SPPB) (dependent variable) and grip strength, pro-inflammatory status and MM (independent variables) adjusted for age and for the total number of chronic diseases. Low SPPB scores were associated with grip strength scores for women (OR 0.86 (95% CI 0.77–0.96)), and for men (OR 0.89 (95% CI 0.81–0.96)). The relationships between low SPPB and MM or inflammatory profile were not significant. Our results show that low physical performance remains associated with low grip strength even after considering other risk factors for sarcopenia in the oldest old and support the hypothesis that low muscle strength is a better indicator than low MM. The role of an inflammatory component in the age-related loss of muscle strength and function could not be confirmed. ß 2013 Published by Elsevier Ireland Ltd. * Corresponding author at: Clos Chapelle-aux-Champs, 30 bte 30.05, 1200 Woluwe-Saint-Lambert (UCL-Brussels), Belgium. Tel.: +32 2 764 34 66; fax: +32 2 7643470. E-mail address: delphine.legrand@uclouvain.be (D. Legrand). G Model AGG-2872; No. of Pages 7 Please cite this article in press as: Legrand, D., et al., The relationship between grip strength and muscle mass (MM), inflammatory biomarkers and physical performance in community-dwelling very old persons. Arch. Gerontol. Geriatr. (2013), http://dx.doi.org/ 10.1016/j.archger.2013.06.003 Contents lists available at SciVerse ScienceDirect Archives of Gerontology and Geriatrics jo ur n al ho mep ag e: www .elsevier .c om /lo cate/ar c hg er 0167-4943/$ – see front matter ß 2013 Published by Elsevier Ireland Ltd. http://dx.doi.org/10.1016/j.archger.2013.06.003