While there is general agreement on the optimal treatment for early Lyme disease, there is considerable controversy over the existence, prevalence, diagnostic criteria, and treatment of "chronic" Lyme disease. The mainstream view is exemplified by a 2007 review in The New England Journal of Medicine, which noted the diagnosis of chronic Lyme disease is used by a few physicians despite a lack of "reproducible or convincing scientific evidence", leading the authors to describe this diagnosis as "the latest in a series of syndromes that have been postulated in an attempt to attribute medically unexplained symptoms to particular infections." Most medical authorities agree with this viewpoint: the IDSA, the American Academy of Neurology, the Centers for Disease Control and Prevention (CDC), and the NIH advise against long-term antibiotic treatment for chronic Lyme disease, given the lack of supporting evidence and the potential toxicities.
A minority view holds that chronic Lyme disease is responsible for a range of unexplained symptoms, sometimes in people without any evidence of past infection. This viewpoint is promoted by many patient advocates, notably an advocacy organization, the International Lyme And Associated Diseases Society. Groups of patients, patient advocates, and the small number of physicians who support the concept of chronic Lyme disease have organized to lobby for recognition of this diagnosis, as well as to argue for insurance coverage of long-term antibiotic therapy, which most insurers deny, as it is at odds with the guidelines of major medical organizations.
In 2006, Richard Blumenthal, the Connecticut Attorney General, opened an antitrust investigation against the IDSA, accusing the IDSA Lyme disease panel of undisclosed conflicts of interest and of unduly dismissing alternative therapies and chronic Lyme disease. The investigation was closed on May 1, 2008, without charges when the IDSA agreed to submit to a review of its guidelines by a panel of independent scientists and physicians which would occur on July 30, 2009. Views on the motivation and outcome of the investigation varied. Blumenthal's press release described the agreement as a vindication of his investigation and repeated his conflict-of-interest allegations. The IDSA focused on the fact that the medical validity of the IDSA guidelines was not challenged, and cited mounting legal costs and the difficulty of presenting scientific arguments in a legal setting as their rationale for accepting the settlement. A journalist writing in Nature Medicine suggested some IDSA members may not have disclosed potential conflicts of interest, while a Forbes piece described Blumenthal's investigation as "intimidation" of scientists by an elected official with close ties to Lyme advocacy groups. The Journal of the American Medical Association described the decision as an example of the "politicization of health policy" that went against the weight of scientific evidence and may have a chilling effect on future decisions by medical associations.
The state of Connecticut went on to enact a law on June 18, 2009, "to allow a licensed physician to prescribe, administer or dispense long-term antibiotics for a therapeutic purpose to a patient clinically diagnosed with Lyme disease." The states of Rhode Island California Massachusetts and New Hampshire have similar laws. The expert panel's review was published in 2010, with the independent doctors and scientists in the panel unanimously endorsing the guidelines, stating "No changes or revisions to the 2006 Lyme guidelines are necessary at this time," and concluding long-term antibiotic treatments are unproven and potentially dangerous. The IDSA welcomed the final report, stating that "Our number one concern is the patients we treat, and we're glad patients and their physicians now have additional reassurance that the guidelines are medically sound."