Accelerometer-Measured, Habitual Physical Activity and Circulating Brain-Derived Neurotrophic Factor: A Cross-Sectional Study

Article type: Research Article

Authors: Spartano, Nicole L.^{a; b; *} | Himali, Jayandra J.^{b; c; d; e; f} | Trinquart, Ludovic^c | Yang, Qiong^c | Weinstein, Galit^g | Satizabal, Claudia L.^{b; d; e; f} | Dukes, Kimberly A.^{c; h} | Beiser, Alexa S.^{b; c; d} | Murabito, Joanne M.^{b; i} | Vasan, Ramachandran S.^{b; i} | Seshadri, Sudha^{b; d; f}

Affiliations: [a] Section of Endocrinology, Diabetes, Nutrition, and Weight Management, Boston University School of Medicine (BUSM), Boston, MA, USA | [b] Framingham Heart Study, Framingham, MA, USA | [c] Department of Biostatistics, Boston University School of Public Health (BUSPH), Boston, MA, USA | [d] Department of Neurology, BUSM, Boston, MA, USA | [e] Department of Population Health Sciences, University of Texas Health Science Center, San Antonio, TX, USA | [f] Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, University of Texas Health Science Center, San Antonio, San Antonio, TX, USA | [g] School of Public Health, University of Haifa, Haifa, Israel | [h] Biostatistics and Epidemiology Data Analysis Center, BUSPH, Boston, MA USA | [i] Departments of Medicine and Epidemiology, BUSM and BUSPH, Boston, MA, USA

Correspondence: [*] Correspondence to: Nicole Spartano, PhD, Boston University School of Medicine, Section of Endocrinology, Diabetes, Nutrition & Weight Management, 720 Harrison Avenue, Doctors Office Building, Suite 8100, Boston, MA 02118, USA. Tel.: +1 315 415 2040l; E-mail: Spartano@bu.edu.

Abstract: Background:One of the mechanisms suggested to link physical activity (PA) to favorable brain health is through stimulation of neural growth factors such as brain-derived neurotrophic factor (BDNF). Acute bouts of PA stimulate circulating BDNF levels. Objective:In this investigation, we assessed whether habitual, accelerometer-measured PA levels were related to circulating BDNF levels in a middle-aged cohort. Methods:In the Framingham Heart Study Third Generation cohort, 1,769 participants provided reliable accelerometry data and were not missing BDNF measurement or platelet counts. In a cross-sectional analysis, using multivariable regression, we related PA measures to serum BDNF levels, adjusting for age, sex, smoking status, platelet count, depression status, and accelerometer wear time. Results:Our study participants (mean age 47±9 years, 50.8% women) spent an average of 22.3 mins/day in moderate-to-vigorous (MV)PA. Most PA variables (steps, MVPA, light activity, and sedentary time) were not related to BDNF levels (p > 0.05). We observed a non-linear trend, where 15–50 mins/week vigorous activity was associated with lower BDNF compared to those with 0 min vigorous activity (β= –0.049±0.024, p = 0.05), but with no significant associations at lower or higher vigorous activity levels. In smokers, MVPA was also associated with lower BDNF levels (β= –0.216±0.079, p = 0.01). Conclusion:Our study reveals that circulating BDNF is not chronically elevated in individuals with higher levels of habitual PA in middle-aged adults from the community and may even be chronically suppressed with higher PA in subgroups, including current smokers. These results do not contradict previous studies demonstrating that circulating BDNF rises acutely after PA.

Keywords: Epidemiology, exercise, growth factor, sedentary time

DOI: 10.3233/JAD-215109

Journal: Journal of Alzheimer's Disease, vol. 85, no. 2, pp. 805-814, 2022