Journal
BMJ OPEN
Volume 7, Issue 7, Pages -Publisher
BMJ PUBLISHING GROUP
DOI: 10.1136/bmjopen-2017-016064
Keywords
-
Categories
Funding
- Transdisciplinary Research on Energetics and Cancer (TREC) Center at Washington University in St Louis
- Alvin J Siteman Cancer Center
- Barnes-Jewish Hospital Foundation
- Washington University School of Medicine
- National Cancer Institute at NIH [U54 CA155496]
- NATIONAL CANCER INSTITUTE [U54CA155496] Funding Source: NIH RePORTER
Ask authors/readers for more resources
Objectives Circulating 25-hydroxyvitamin D (25-OHD) is associated with improved cancer prognosis in some studies, yet it may be a surrogate marker for physical activity. We investigated the associations of leisure-time physical activity (LTPA) with circulating 25-OHD levels in cancer survivors, and determined whether associations differ by indoor and outdoor activity. Design Cross-sectional study. Setting The US National Health and Nutrition Examination Survey (NHANES). Participants Cancer survivors with available data on demographic information, measures of adiposity, smoking history, self-reported LTPA and circulating 25-OHD levels in five waves of NHANES (2001-2010). Main outcomes measures Circulating 25-OHD levels. Results Multivariable linear regression and logistic regression models were used to evaluate the associations of self-reported LTPA with 25-OHD, adjusting for potential confounders. Due to the differences in LTPA measure, the analyses were conducted separately for 2001-2006 and 2007-2010 data. We further estimated associations by indoor and outdoor activity in the 2001-2006 data. There were 1530 cancer survivors (mean age=60.5 years, mean body mass index=28.6 kg/m(2)). The prevalent cancer sites were breast (19.3%), prostate (18.8%), cervix (10.4%) and colon (8.6%). Compared with inactive cancer survivors, being physically active was associated with higher circulating 25-OHD levels (8.07 nmol/L, 95% CI 4.63 to 11.52) for 2001-2006 data. In the mutually adjusted model, higher outdoor activity (5.83 nmol/L, 95% CI 1.64 to 10.01), but not indoor activity (2.93 nmol/L, 95% CI -1.80 to 7.66), was associated with statistically significantly higher 25-OHD levels. The interaction between indoor and outdoor activities was, however, not significant (p=0.29). The only statistically significant association seen in the 2007-2010 data was among obese cancer survivors. Conclusion Physical activity, particularly outdoor activity, is associated with higher 25-OHD levels in cancer survivors. In view of the possible beneficial effects of vitamin D on cancer prognosis, engaging in outdoor physical activity could provide clinically meaningful increases in 25-OHD levels among cancer survivors.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available