INTERNET DISCUSSIONS ABOUT AI USAGE 

It is no surprise that breast cancer patients using aromatase inhibitors (AI) post notes about their drug experiences on the Internet and sometimes discuss adverse effects. A new study examining which adverse effects are discussed online has found that musculoskeletal pain is at the top of the list, followed by vasomotor symptoms, bone loss/osteoporosis, and weight gain.

The findings are published online January 16 inPharmacoepidemiology and Drug Safety.

The relative frequency of key adverse effects mentioned in the forums reflects the frequency reported in large clinical trials, the researchers note.

"In a sense, the Internet offers patients a safe place to voice their perspectives," lead researcher Jun Mao, MD, director of integrative medicine at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia, told Medscape Medical News.

Women openly cite concerns about the drugs, discuss their struggles to balance the risks and benefits, and offer support and suggestions to one another.

However, although online communication can be a great source of comfort, it can also cause distress. Patients need understand that people deal with illnesses and drugs differently. "They cannot assume that they will be the ones who get the worst of symptoms or have the worst outcomes," she explained.

AIs are widely used to treat breast cancer and are considered to be standard adjuvant therapy for preventing the recurrence of hormone-receptor-positive breast cancer. However, they are associated with significant musculoskeletal adverse effects, including joint pain and stiffness.

Previous research has shown that breast cancer survivors use the Internet to research their diagnosis, treatment options, and ways to control adverse events, Dr. Mao and colleagues note. However, little is known about the extent to which patients use social media to discuss adverse effects related to medications.

Wide Range of Discussion

In this mixed-methods study, the researchers examined the volume and frequency of content related to AI-associated adverse effects posted on the message boards of 12 popular Web sites from 2002 to 2010, including WedMD, breastcancer.org, Susan G. Komen for the Cure, and Oprah.com.

Of 1,235,400 posts, 25,256 mentioned at least 1 of 3 specific AIs, and 4589 (18.2%) discussed at least 1 adverse effect related to those AIs.

Among the commonly cited adverse effects associated with AI use were musculoskeletal pain (5093 mentions); vasomotor symptoms, including hot flashes and night sweats (1498 mentions); bone loss and/or osteoporosis (719 mentions); and weight gain (429 mentions).

Of 1000 randomly selected posts related to arthralgia, 829 (82.9%; 95% confidence interval, 80.4% - 85.2%) mentioned joint pain directly related to AI use. Other posts indicated that joint pain was related to other causes or offered an opinion that pertained to AI-associated arthralgia.

In these 1000 posts, 862 patients specifically mentioned 1 of the 3 AIs. Of these, 110 (12.8%) patients mentioned discontinuing an AI with no intention of trying another one, 201 (23.3%) made 1 switch, and 41 (4.8%) switched therapies twice (i.e., used all 3 AIs).

Of the 1000 posts, 742 (74.2%) mentioned continuing AI therapy. Of those, 199 (26.8%) cited being able to manage joint pain as the reason for continuing AI therapy. Even when joint pain was a great inconvenience, 77 (10.4%) posters felt that the benefits outweighed the adverse effects of AIs.

Of the 110 women who had stopped using AIs, 100 (90.9%) reported frequent debilitating pain related to AIs, and felt that pain outweighed the benefit of preventing disease recurrence. Other reasons for stopping included different adverse effects, cost, and perceived ineffectiveness of the drug.

The most common mechanisms for dealing with arthralgia were nonsteroidal anti-inflammatory drugs, cyclooxygenase-2 inhibitors, and acetaminophen. Some patients also mentioned receiving corticosteroid injections when pain was severe, and using herbal or mineral supplements.

The study was supported by a challenge grant from the National Library of Medicine. Dr. Mao reports receiving support from the American Cancer Society and National Institutes of Health, and serving as an advisor to Pfizer on research unrelated to breast cancer. Coauthor Charles Leonard, PharmD, from the Perelman School of Medicine, reports receiving research funding from AstraZeneca for studies unrelated to breast cancer. Coauthor Sean Hennessy, PharmD, from the Perelman School of Medicine, reports receiving research funding from AstraZeneca and consulting with Novartis for research unrelated to breast cancer.

Pharmacoepidemiol Drug Saf. Published online January 16, 2013. Abstract