How Healthy are “Healthy Volunteers?”

A recent study (V Takyar et al. Hepatology 2017; 66: 825-33) examined a total of 3160 subjects enrolled in 149 clinical trials from 2011-2015.  These patients were derived from the NIH Clinical Center, ≥18 years, had ALT and BMI measurements available. Presumed NAFLD (nonalcoholic fatty liver disease) was classified if patient had elevated ALT (≥20 for women and 31≥ for men) along with BMI >25 kg/m-squared.

Key findings:

  • 27.9% (n=881) of these healthy volunteers had presumed NAFLD.  These patients also had higher triglycerides, low-density lipoprotein, cholesterol and HbA1c (P<0.001 for all)
  • The authors note that the presence of these presumed NAFLD as controls “likely” affected the study validity in 10 studies and “probably” affected another 41 studies.

My take: This study shows that patients with presumed NAFLD are often enrolled in research studies as healthy controls.  Furthermore, this can affect study outcomes.

Related blog posts:

Lover’s Leap, NC -Appalachian Trail