Serum vitamin D levels decreased significantly from baseline to @ weeks among those randomized to efavirenz/lamivudine/zidovudine ( mean change : -@ -LSB- @ % Confidence Interval ( CI ) -@ , -@ -RSB- ng/ml ) and efavirenz/emtricitabine/tenofovir-DF ( mean change : -@ -LSB- @ % CI -@ , -@ -RSB- ng/ml ) when compared to those randomized to atazanavir/emtricitabine/didanosine-EC ( mean change : -@ -LSB- @ % CI -@ , @ -RSB- ng/ml ) .