At week 48 , the LDL subfraction phenotype improved in the darunavir/ritonavir arm ( increase in LDL particle size and in large LDL particles ) , whereas it worsened in the atazanavir/ritonavir arm ( increase in small and dense LDL particles , shift to a greater prevalence of phenotype B ) ; the worsening was related to the greater increase in triglycerides in the atazanavir/ritonavir arm .