intenta con este codigo
Dim born As New DateTime(DateTimePicker1.Value.Year, DateTimePicker1.Value.Month, DateTimePicker1.Value.Day)
Dim today As New DateTime(DateTime.Now.Year, DateTime.Now.Month, DateTime.Now.Day)
Dim x As New DateTime(today.AddTicks(-born.Ticks).Ticks)
Label3.Text = String.Format("{0} - {1} - {2}", x.Year - 1, x.Month - 1, x.Day - 1)