Now, after SAMSON, “I have an additional point that I’m going to tell them: out of the patients that get muscle aches, probably 90% of that is the anticipation of getting the statin, the nocebo effect,” said Dr. Khera, who directs the preventive cardiology program at the University of Texas Southwestern Medical Center, Dallas.
In practice, however, many patients who report adverse statin effects do so later than 2 weeks after starting therapy, “so these findings cannot be generalized to them,” proposed Francine K. Welty, MD, PhD, Beth Israel Deaconess Medical Center, Boston, as the invited discussant after Dr. Howard’s presentation.
All 60 patients recruited for SAMSON had previously stopped taking a statin because of side effects that arose within 2 weeks of their first dose. That requirement was intended to boost chances that any further symptoms during the trial would arise within a month of starting each new round of pills, Dr. Howard said.
So the trial’s results, Dr. Welty said, “are limited to those subjects who develop symptoms within 2 weeks of starting a statin.”
Including only such patients may have created bias toward a nocebo effect, she said, because “non–drug-related side effects of medications are often greatest during the initial weeks of treatment and tend to abate over time.” For example, “metformin causes diarrhea and beta-blockers cause fatigue, but subjects do adapt and generally tolerate them very well.”
The patients, 25 women and 35 men, 90% of whom were white, received four pill bottles, each with a month’s supply of atorvastatin, four bottles each with 1 month of placebo, and four empty bottles each, to be used double blind for a month in randomized order.
Patients used the smartphone app to document their symptom scores, which ranged from 0 for no symptoms to 100 for symptoms that were the “worst imaginable,” the published report noted. Patients who experienced symptoms so severe as to be intolerable could stop the 1-month regimen they were then following, with instructions to resume the regimens in order starting the next month.
Eleven patients were unable to complete all 12 1-month segments of the trial.
The study’s overall “nocebo ratio” of 0.90 was calculated as the difference between symptom intensity scores on placebo and on no treatment divided by the difference between symptom intensity on the statin and on no treatment. The interpretation: 90% of the symptom burden felt by patients receiving atorvastatin was also felt during placebo use.
A total of 30 patients, contacted 6 months after the trial concluded, had resumed taking a statin, while “4 planned to do so and one could not be contacted,” the report noted. The 25 other patients weren’t receiving a statin and had no plans to take one.
In an important part of the trial, Dr. Howard said, at its conclusion the patients were shown their pattern of symptoms in relation to whether they were taking the statin, placebo, or neither. “Participants could see as clearly as we could the surprisingly powerful magnitude of the nocebo effect. And this led to half of our patients happily restarting statins.”