Examining the Nocebo Effect of Statins Through Statin Adverse Events Reported in the FDA Adverse Event Reporting System (FAERS)
Background: This study aimed to evaluate whether the high frequency of reported statin adverse effects (AEs) may be associated with the nocebo effect. We compared nocebo-related subjective AEs with objective AEs and investigated factors potentially associated with the nocebo effect.
Methods: A retrospective cohort study was conducted using the FDA Adverse Event Reporting System (FAERS) between January 2010 and December 2019 for statins, including, atorvastatin, lovastatin, pravastatin, rosuvastatin, and simvastatin. Subjective AEs included fatigue, subjective muscular, and nervous system AEs. Objective AEs were defined as hepatic and objective muscular AEs. We compared the number of subjective and objective AEs using the Mann-Whitney U test and examined trends in the frequency of subjective versus objective reports over time using linear regression with interaction terms. We evaluated the association between AEs and gender and country using linear regression. Quantitative detection of signals was estimated using proportional reporting ratio (PRR) and reporting odds ratio (ROR) for simvastatin.
Results: Of 2,994,487 overall AE reports, more subjective than objective AEs were reported per quarter (mean±SD: 4,777±1,375.45 vs 999±276.95; p<0.0001), and over time during the study period (p<0.001). Females reported more subjective AEs than males per quarter (fatigue: 86.98 more per quarter, p=0.035; subjective muscular AE: 417.95, p<0.0001; nervous system AE: 273.60, p<0.0001), but fewer objective muscular AEs (-125.23 per quarter, p<0.0001). More subjective AEs and fewer objective AEs were reported per quarter in the US relative to other countries. Simvastatin-associated reports showed signals for higher objective muscular AEs relative to all other statins (ROR 1.53, 95% CI: 1.49-1.58).
Conclusions: This study found that significantly more subjective than objective AEs are reported for statins. Subjective statin AEs, potentially related to the nocebo effect are reported more often by females than by males, and in the US than in other countries.