Association Between Physical Activity Level and Cardiovascular Risk Factors in Adolescents Living with Type 1 Diabetes: A Cross-sectional Study

Background: Type 1 diabetes (T1D) is associated with a high risk of cardiovascular disease (CVD) and an increased rate of premature mortality from CVD. Regular physical activity can improve overall health and wellbeing and plays an important role in primary and secondary prevention of CVD. Methods: This cross-sectional study assessed cardiovascular risk factors, physical activity, and fitness (and their associations) in young individuals living with T1D and healthy controls. Primary outcomes included blood pressure, lipid profiles, and physical activity (accelerometry). We included a total of 48 individuals living with T1D and 19 healthy controls, aged 12 to 17 years. Statistical differences between groups were determined with chi-square, independent-samples t-tests or analysis of covariance. The associations between aerobic fitness, daily physical activity variables and cardiovascular risk factors were assessed with univariate and multivariate linear regression analysis.Results: In comparison to healthy controls, youth living with T1D showed higher levels of total cholesterol (4.03 ± 0.81 vs. 3.14 ± 0.67 mmol·L-1, p = 0.001), low-density lipoprotein cholesterol (LDL-C) (2.31 ± 0.72 vs. 1.74 ± 0.38 mmol·L-1, p = 0.035), and triglycerides (0.89 ± 0.31 vs. 0.60 ± 0.40 mmol·L-1 p = 0.012), and lower maximal oxygen power (VO2max) (35.48 ± 8.72 vs. 44.43 ± 8.29 mL·kg-1·min-1, p = 0.003), total physical activity counts (346.87 ± 101.97 vs. 451.01 ± 133.52 counts·min-1, p = 0.004), metabolic equivalents (METs) (2.09 ± 0.41 vs. 2.41 ± 0.60 METs, p = 0.033), moderate to vigorous intensity physical activity (MVPA), and the percentage of time spent in MVPA. The level of HDL-C was positively associated with METs (β = 0.29, p = 0.030, model R2 = 0.17), and the level of triglycerides was negatively associated with physical activity counts (β = -0.001, p = 0.018, model R2 = 0.205) and METs (β = -0.359, p = 0.015, model R2 = 0.208) in persons living with T1D. Conclusions:Youth with T1D, despite their young age and short duration of diabetes, present early signs of CVD risk, as well as low physical activity levels and cardiorespiratory fitness compared to healthy controls. Regular physical activity is associated with a beneficial cardiovascular profile in T1D, including improvements in lipid profile. Thus, physical activity participation should be widely promoted in youth living with T1D.