profilebase.create(username) causes user to appear online

I'm experiencing something and I want to validate that this is what I'm seeing, and see if anyone has any ideas regarding how to aleviate it.

I have a page where I pull some information from several user profiles. To to this, I'm using the following code:

Dim objProfiles As New List(Of ProfileCommon)
For Each theProfile As ProfileInfo In _ 
开发者_StackOverflow中文版    ProfileManager.GetAllProfiles(ProfileAuthenticationOption.All)
    Dim pc As ProfileCommon = ProfileBase.Create(theProfile.UserName)
    objProfiles.Add(pc)
Next
Return objProfiles

What I'm finding is, that once I do this all the user's who profiles I have pulled now show as online in our user administration page. I have two questions:

1-What is causing this to happen? I do cache the information as well once I compile it, is it becuase it's still cached? Is it becuase I loaded and then didn't unload profiles? and if so,

2-What do I do to make the user now appear NOT online again?