SqlDataReader Multi Connections

I noticed that when SqlDataReader is pending, if another page require the same connection the page remain in work tail until SqlDataReader in first page is closed.
It is a real disappointment for a multi tasking system like Windows.
How to absolutely avoid it?

Imports Microsoft.VisualBasic
Imports System.Data
Imports System.Data.SqlClient
Public Class var
    Public Structure varName
        Public backUserColor, borderUserColor As String
    End Structure
    Public Shared Function getVar(ByVal pageCode As String, ByVal level1 As String) As varName
        Dim connection As New SqlConnection("Data Source=.SQLEXPRESS;AttachDbFilename='G:Documents and SettingsAdministratorDocumentiVisual Studio 2005WebSitesWebSite1App_Datavar.mdf';Integrated Security=True;Asynchronous Processing=True;Connect Timeout=30;User Instance=True")
        Dim query As String = "SELECT value FROM common UNION ALL SELECT spec FROM spec WHERE pageCode='"+pageCode+"'"
        Dim command As New SqlCommand(query, connection)
        connection.Open()
        Dim reader As SqlDataReader = command.ExecuteReader()
        While reader.Read
            getVar.backUserColor = reader.Item(0)
            MsgBox(getVar.backUserColor, , )
 
        End While


        reader.Close()
        connection.Close()
    End Function
End Class