VARIANT_BOOL and BOOL

Hi, I wonder what is the difference between VARIANT_BOOL and BOOL, in specific, can I use the following code:

bool CMyDlg::LoadResultXML(CString strXMLPathName)
{

	HRESULT hr = m_plDomDocument.CreateInstance(CLSID_DOMDocument);
	
	if (FAILED(hr))
	{
		_com_error er(hr);
		AfxMessageBox(er.ErrorMessage());
		EndDialog(1);
	}

	_bstr_t bstrXMLPath;
	bstrXMLPath = strXMLPathName.AllocSysString();

        return m_plDomDocument ->load(bstrXMLPath);

}