>>In univariate models, each 10ng/ml higher vitamin D level was associated with a 15% lower risk of later developing new T2 lesions (IRR, 0.85; 95% CI, 0.76?0.95; p = 0.005). The multivariate results were nearly identical (Table 3). Younger age and cigarette smoking were also associated with increased risk of new T2 lesions. The estimates did not meaningfully change when disease duration, BMI, or HLA-DRB1 status was added to the models, nor did they change if DMT was modeled as a categorical variable or if a person was considered to be on DMT who had received it for at least 3 months of the prior interval. Even after adjusting for baseline vitamin D, each 10ng/ml within-person increase in vitamin D was associated with a much lower risk of developing a new T2 lesion (IRR, 0.67; 95% CI, 0.55?0.83; p < 0.001).<<