Abstract 4256: Handgrip strength and cognitive function in elderly cancer survivors
Authors: Yang Lin , Smith Lee , Hu Liang , Colditz Graham A. , Toriola Adetunji T. , Vancampfort Davy , Hamer Mark , Stubbs Brendon , Waldhör Thomas 
Published: August 2018

Abstract
Aim: Cancer and cancer treatment-related cognitive impairments are frequently reported in cancer survivors, presenting as lack of attention, impaired executive function and short-term money loss. The aetiology of these impairments is largely unknown. Recently, serum level of brain-derived neurotrophic factor (BDNF) has been associated with cancer related cognitive impairments. BDNF is a neurotrophin, secreted in responses to muscle contraction. Meanwhile, muscle dysfunction, characterized by muscle strength and muscle composition, is common in cancer survivors. Yet its impact on cancer survivors' cognitive function is unknown. To address this gap we evaluated for the first time the associations of muscle strength determined by handgrip with two cognitive function outcomes in cancer survivors using data from the National Health and Nutrition Examination Survey (NHANES). Method: Data in two waves of NHANES (2011-2014) were aggregated. Handgrip strength in kilogram (kg) was measured with the Takei Digital Grip Strength Dynamometer, defined as the maximum value achieved using either hand. Data on two cognitive function tests were extracted, both were conducted among adults 60 years and older: the Animal Fluency Test (AFT) which examines categorical verbal fluency (a component of executive function), and the Digital Symbol Substitution test (DSST) which assesses processing speed, sustained attention and working memory. Survey analysis procedures were used to account for the complex sampling design of the NHANES. Gender-specific multivariable linear regression models were used to estimate associations of handgrip strength with cognitive test scores, adjusting for confounders (age, gender, race/ethnicity, education, marital status, smoking status, depression and leisure time physical activity). For explorative purpose, we further adjusted for handgrip strength squared. Results: There were 383 cancer survivors (mean age=70.9 years, mean BMI=29.3 kg/m2) with detailed data for analyses. Prevalent cancer types were breast (22.9%), prostate (16.4%), colon (6.9%) and cervix (6.2%). The prevalence of handgrip strength defined sarcopenia was 10.9% in men (&lt;30kg) and 20.4 % in women (&lt;20kg). Scores on AFT and DSST were 18.0 (s.e. 0.4) and 51.7 (s.e. 1.0), respectively. We observed significant linear associations of handgrip strength with both test scores in women. Each increase kg of handgrip strength was associated with 0.20 (95% CI: 0.08 to 0.33) higher score on AFT and 0.83 (95% CI: 0.30 to 1.35) higher score on DSST. In men, we observed inverted U-shape association between handgrip strength and DSST score, which peaked at handgrip strength of 40-42 kg. Conclusion: Handgrip determined muscle strength appears to be associated with aspects of cognitive functions in cancer survivors. Prospective studies are needed to identify the role of muscle on cancer related-cognitive impairments in men and women cancer survivors.
Citation Format: Lin Yang, Lee Smith, Liang Hu, Graham A. Colditz, Adetunji T. Toriola, Davy Vancampfort, Mark Hamer, Brendon Stubbs, Thomas Waldhör. Handgrip strength and cognitive function in elderly cancer survivors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4256.