News From The Annals Of Internal Medicine: Feb. 19, 2013
Patients receiving acupuncture treatments for seasonal allergic rhinitis reported statistically significant improvements in symptoms and decreased use of medication compared to patients having standard treatment or sham acupuncture, but the clinical significance of the observed improvements is uncertain. Allergic rhinitis (stuffy or runny nose caused by allergies) is an extremely common condition that affects approximately 20 percent of the U.S. population. Despite the availability of effective medications such as antihistamines, patients suffering from allergic rhinitis often seek alternative therapies for symptom relief. Researchers randomly assigned 422 patients between the ages of 16 and 45 to receive 12 treatments of either acupuncture plus rescue medication (n=212); sham acupuncture plus rescue medication (n=102); or rescue medication alone (n=108) over an eight-week period during two consecutive allergy seasons. All patients in the trial could take up to two doses of cetirizine per day. If their symptoms were not adequately controlled with cetirizine, participants could be treated with an oral corticosteroid, but use of other anti-allergy medications was prohibited. After the first eight weeks, patients assessed their symptoms and reported use of medications. Patients in the acupuncture plus rescue medication group had statistically significant improvements in disease-specific quality of life and medication use compared with the other two groups. This difference waned at the 16-week follow-up. While the researchers cannot be sure if patient expectations about acupuncture affected their outcomes, the author of an accompanying editorial suggests that future acupuncture research should, as this study did, use acupuncture protocols that represent true clinical practice and compare acupuncture to other proven therapies rather than to sham acupuncture alone.
*A link to the summary for patients is free to the public.
2. Researchers Assess the Benefits and Risks of Redefining a Positive CT Result for Lung Cancer
Using a threshold of 7 or 8 mm to define a positive lung cancer result in a baseline round of computed tomography (CT) could decrease false positive screening results. However, prospective research is needed to determine whether increasing the threshold may delay diagnosis of cancer in some patients. In CT screening for lung cancer, the positive result of the initial low-dose CT indicates whether further diagnostic work-up is needed before the first scheduled repeated screening. A definition that is too inclusive may cause excessive diagnostic work-up and unnecessary treatment, while a definition that is too restrictive may delay diagnosis. In the past decade, the frequency of identifying a noncalcified nodule (NCN) of any size on the initial baseline CT scan has almost tripled. This is mostly due to technological advances in CT scanners and the use of large computer monitors to display the CT images. Changing the size threshold for a positive screening could help reduce the harms associated with unnecessary, invasive work-up of false positive screening tests. Researchers reviewed medical records for a cohort of 21,136 patients who had a baseline CT performed between 2006 and 2010 to assess how using a more restrictive threshold in the baseline round of screening would affect the number of positive results and delayed diagnoses. Of the participants undergoing baseline screenings, 57 percent had at least one NCN discovered. By using the current definition of 5 mm, 16 percent (3,396 of the 21,136 patients) had a positive result. Of those, 8 were diagnosed with lung cancer within 12 months of baseline enrollment. Increasing the threshold to 6, 7, 8, and 9 mm would have lowered the frequency to 10, 7, 5, and 4 percent respectively, thus decreasing further work-up by 36, 56, 68, and 75 percent respectively. The authors of an accompanying editorial express concern that nodule size may not be the best indicator of cancer risk. Other variables, such as presence of emphysema or nodule spiculation could predict which nodules are likely to be cancerous. The editorialists call for development of a comprehensive computer-based risk calculator that integrates nodule and demographic information.
3. Task Force Reviews Evidence to Inform Recommendations for Treating Open-Angle Glaucoma
** Draft recommendation posted for public comment.
A panel of experts commissioned to review evidence on glaucoma treatment to inform an upcoming U.S. Preventive Services Task Force recommendation found insufficient evidence to directly compare the effectiveness of medical, laser, and surgical treatments for open-angle glaucoma. Glaucoma is an acquired degeneration of the optic nerve that is the second most common cause of blindness worldwide. Open-angle is the most common type of glaucoma where an increase in pressure on the optic nerve occurs slowly over time. Open-angle glaucoma tends to run in families, with African Americans being at a high risk. The researchers reviewed published evidence to assess treatments' effectiveness at decreasing intraocular pressure and preventing optic nerve damage, vision loss, and visual impairment. High-level evidence suggests that both medical and surgical treatments for glaucoma decrease intraocular pressure and protect against worsening visual field loss, with surgical treatment (trabeculectomy) being slightly more effective. Reviews comparing timolol with travoprost and latanoprost showed the prostaglandins to be more effective at decreasing intraocular pressure. However, prostaglandins were also more likely to cause eye redness. The reviewers found insufficient evidence linking treatment of any kind to patient-reported outcomes or visual impairment.