P2500The high-sensitivity cardiac troponin I and T response following strenuous activity is attenuated by smokeless tobacco:The North Sea Race Endurance Exercise Study (NEEDED) 2014

Abstract

Abstract Background Use of snus, a smokeless oral tobacco product, is increasing among athletes and recreational exercisers in Scandinavia. Strenuous physical activity is associated with an acute increase in high-sensitivity cardiac troponins (hs-cTn) in healthy individuals. Current smoking is associated with lower baseline hs-cTn concentrations in current smokers in the general population, but whether tobacco affects the hs-cTn response to exercise remains unknown. Methods We measured serial cTnI and cTnT concentrations in 1002 healthy recreational athletes before, 3 and 24 h after a 91 km bicycle race. Self-reported snus habits were reported as: non-current (n=794) and current (n=118). The association between snus use and change in log hs-cTnI and hs-cTnT (differences between concentrations at baseline and 3 h (Δ3 h) and 24 h (Δ24 h)) were assessed by multivariable linear regression analysis. Results Current snus use was associated with lower cTnI (current users of snus vs non-current: median, 1.7 ng/l; interquartile range (IQR), 1.6–2.3 vs 2.0 ng/L; IQR 1.6–3.2; p=0.020) and cTnT (current users of snus vs non-current: median, 3.0 ng/L, IQR, 3.0–3.5 vs 3.0 ng/L, IQR 3.0–4.3; p=0.021) concentrations at baseline. Both in unadjusted and fully adjusted linear regression models, users of snus had significantly lower Δ3 h and Δ24 h cTnI and cTnT concentrations (Table). Association between snus use and change in concentrations of hs-cTnI and hs-cTnT (95% CI) Model 1 Model 2 Model 3 Model 4 ΔcTnI 3 h Current snus −28% (−46% to −10%), p=0.003 −33% (−51% to −14%), p=0.001 −31% (−49% to −13%), p=0.001 −29% (−47% to −11%), p=0.002 ΔcTnI 24 h Current snus −38% (−62% to −15%), p=0.002 −36% (−59% to −12%), p=0.003 −32% (−56% to −9%), p=0.007 −30% (−54% to −7%), p=0.010 ΔcTnT 3 h Current snus −28% (−10% to −46%), p=0.003 −33% (−51% to −14%), p=0.001 −31% (−49% to −13%), p=0.001 −29% (−47% to −11%), p=0.002 ΔcTnT 24 h Current snus −20% (−4% to −36%), p=0.015 −23% (−39% to −8%), p=0.004 −21% (−36% to −5%), p=0.009 −19% (−34% to −14%), p=0.013 Model 1 unadjusted; Model 2 adjusted for sex and age; Model 3 adjusted for Model 2 and systolic blood pressure, body mass index, low-density lipoprotein and estimated glomerular filtration rate; Model 4 adjusted for the same variables as in Model 3 but also race duration and resting heart rate. Conclusion The exercise-induced cTn response in healthy recreational cyclist is attenuated in users of smokeless tobacco compared to never users. These findings extend observations of lower hs-cTn concentrations in tobacco smokers in the general population. Acknowledgement/Funding Operating grant from North Sea Race, Abbot Diagnostics, Lærdal Foundation. PhD fellowship from South-Eastern Norway Regional Health Authority.