Due to prohibitive costs, almost 40 million Americans forewent prescription drugs in 2008, according to a Manhattan Research report.

Women and patients with neurological and mental health conditions were the most likely to refrain from purchasing prescription meds, according to the findings. Patients with fibromyalgia were more likely to forego prescription drugs than patients with other chronic conditions.

The report lists 10 condition groups most affected by drug costs, with the aforementioned fibromyalgia topping the list. The others are as follows, in descending order:

  • inflammatory bowel disease
  • generalized anxiety disorder
  • chronic bronchitis
  • chronic pain
  • acute pain
  • adult ADHD
  • anxiety disorder/social phobia
  • depression

Meredith Abreu Ressi, vice president of research at Manhattan Research, said that one of the reasons fibromyalgia patients were opting out of costly prescriptions stems from the disorder’s controversial status. 

“Patients may face some resistance from insurance companies in getting coverage for prescription medications approved for the condition, such as Lilly’s Cymbalta and Pfizer’s Lyrica,” said Ressi.