Fibromyalgia Diagnoses Drop After the Implementation of 2016 Guidelines

A new study found that the latest fibromyalgia criteria established in 2016 might not catch the full complexity of fibromyalgia in patients who also have other health issues, compared to the older 2010 criteria.1

In fact, after the implementation of the modified 2010 criteria, which had a sensitivity of 84% and a specificity of 87%, there was a spike in fibromyalgia diagnoses, rising from 0.58% in 2010 to 0.99% in 2011.2 However, after the implementation of the modified 2016 criteria, diagnosis rates dropped from around 0.8% throughout the early 2010s to 0.27% by 2019.1

“Based on the findings of this study, we hypothesize that perhaps the specificity of the 2016 criteria for fibromyalgia diagnosis, which aimed to minimize the misclassification of regional pain disorders and combine patient reports of the severity of the symptoms (FS score) with a physician assessment moved too far in the categorical direction for a disorder as complex and multi-dimensional as fibromyalgia,” wrote investigators, led by Anthony Rubano, from the department of pharmaceutical & clinical Sciences at Campbell University in North Carolina.

The American College of Rheumatology (ACR) established the initial diagnostic benchmarks for fibromyalgia in 1990, stating patients must have a history of widespread pain for ≥ 3 months and pain in 11 of 18 tender point sites at high-mobility locations. These guidelines led to many misdiagnoses, so ACR updated the criteria in 2010 and then again in 2011. The 2016 fibromyalgia guidelines, which rheumatologists currently use, combine the 2010 and 2011 criteria.

Still, the 2016 guidelines continue to lead to misdiagnoses. Investigators sought to assess the changes in the incidence of fibromyalgia diagnoses and links between a fibromyalgia diagnosis and relevant comorbidities or somatic symptoms.

The retrospective, observational, cross-sectional study of adults aged 18 years used National Ambulatory Medical Care Survey datasets from 2010 to 2019. Among the 348,164 visits, 60.2% were female, 83.4% were White, and 90.9% visited an urban ambulatory care center. The frequent comorbidities were diabetes (15.3%) and depression (11.5%), with other comorbidities recorded at ≤ 1 visit. A fibromyalgia diagnosis was reported in 0.7% of visits.

The study observed an increase in fibromyalgia diagnoses following the implementation of the 2010 ACR criteria but a drop after the release of the 2016 criteria.

Rheumatoid arthritis (odds ratio [OR], 5.51; 95% confidence interval [CI], 2.87 – 10.58) and depression (OR, 2.61; 95% CI, 1.90 – 3.58) were both strongly linked to a fibromyalgia diagnosis.

A multivariable logistic regression model found visits involving a rheumatoid arthritis diagnosis have 451% greater odds of receiving a fibromyalgia diagnosis (OR, 5.51; 95% CI, 2.87 – 10.58). Additionally, visits where depression was diagnosed had 161% greater odds of fibromyalgia diagnosis (OR, 2.61; 95% CI, 1.90 – 3.58).

Other comorbidities, including diabetes, generalized anxiety disorder, malaise, lupus, or IBIS, had no associations with fibromyalgia. Investigators said this could be explained by the small number of visits where these conditions were diagnosed.

Females had 183% greater odds (OR, 2.83; 95% CI, 1.95 – 4.11) of receiving a fibromyalgia at a visit than males. Moreover, non-White individuals had 44% lower odds of having fibromyalgia diagnosed.

When it comes to the specific type of physician giving the diagnosis, patients who saw a medical care specialist had 50% increased odds of receiving a fibromyalgia diagnosis (OR, 1.50; 95% CI, 1.04 – 2.18) compared with those who saw a primary care provider. Though patients who saw a surgical care specialist, over a primary care provider, had 71% lower odds of receiving a diagnosis (OR, 0.29; 95% CI, 0.14 – 0.58).

“...the results of this study suggest that the 2016 ACR-established research diagnostic criteria may need to be revised again, given the steady decrease in fibromyalgia diagnoses over most of the last decade,” investigators concluded. “The fibromyalgia-related evidence in this study suggests potential shortfalls of the 2016 criteria, which might have reintroduced issues with underrepresenting the broad spectrum of fibromyalgia, leading to patient frustration, patients being misdiagnosed or undiagnosed, and healthcare providers not getting a complete picture of the patient’s condition.”

References

1. Rubano A, Jiroutek MR, Misciagno SA. The impact of changes in fibromyalgia diagnosis criteria: using NAMCS data (2010-2019) to identify trends. BMC Rheumatol. 2025 Mar 18;9(1):33. doi: 10.1186/s41927-025-00483-1. PMID: 40098011; PMCID: PMC11917024.

2. Wolfe F, Clauw DJ, Fitzcharles MA, Goldenberg DL, Häuser W, Katz RL, Mease PJ, Russell AS, Russell IJ, Walitt B. 2016 Revisions to the 2010/2011 fibromyalgia diagnostic criteria. Semin Arthritis Rheum. 2016 Dec;46(3):319-329. doi: 10.1016/j.semarthrit.2016.08.012. Epub 2016 Aug 30. PMID: 27916278.