Crossover trial of statin, placebo and no treatment to verify side effect patterns and origins

Background: Most people who begin statins abandon them, most commonly because of side-effects. Objectives: Assess daily symptom scores on statin, placebo and no treatment in participants who had abandoned statins. Methods: Participants received 12 one-month medication bottles, 4 containing atorvastatin 20mg, 4 placebo and 4 empty. We measured daily symptom intensity for each using an app (scale 1-100). We also measured the nocebo ratio: the ratio of symptoms induced by taking statin that was also induced by taking placebo. Results: 60 participants were randomized and 49 completed the 12-month protocol. Mean symptom score was 8.0 (95% confidence interval 4.7 to 11.3) in no-tablet months. It was higher in statin months (16.3, 13.0 to 19.6, p<0.001), but also in placebo months (15.4, 12.1 to 18.7, p<0.001), with no difference between the two (p=0.388). The corresponding nocebo ratio was 0.90. In the individual-patient daily data, neither symptom intensity on starting (odds ratio 1.02, 95% CI 0.98 to 1.06, p=0.28) nor extent of symptom relief on stopping (1.01, 95% CI 0.98 to 1.05, p=0.48) distinguished between statin and placebo. Stopping was no more frequent for statin than placebo (p=0.173), and subsequent symptom relief was similar between statin and placebo. 6 months after the trial, 30/60 (50%) of participants were back taking statins. Conclusions: The majority of symptoms caused by statin tablets were nocebo. Clinicians should not interpret symptom intensity or timing of symptom onset or offset (on starting or stopping statin tablets) as indicating pharmacological causation, because the pattern is identical for placebo. ClinicalTrials.gov: NCT02668016