Weight-Loss Surgery With Fibromyalgia: A Danish Nationwide Study

Weight-Loss Surgery With Fibromyalgia: A Danish Nationwide Study

Many people with fibromyalgia also live with obesity, and some wonder whether weight-loss surgery is a safe option. A Danish study compared outcomes after metabolic bariatric surgery in people with and without fibromyalgia. The risk of complications was not higher with fibromyalgia, but the group was small. The study appeared in Obesity Surgery on November 4, 2026.

The Study

Researchers from Zealand University Hospital used Danish national registers. They looked at adults who had metabolic bariatric surgery in Denmark between 2008 and 2018. They matched each patient with fibromyalgia to about six patients without it, using a statistical method (propensity-score matching) that makes the groups comparable on age, weight and other factors.

• 54 women with fibromyalgia
• 292 women without fibromyalgia
• Follow-up of about nine years (median) in both groups

The Results

• Complications: no significant difference in early complications (within 30 days) or in later complications, up to eight years after surgery. This held for both major and minor complications.
• Weight loss: did not differ between the groups.
• Quality of life: improved in both groups. After one year, the improvement was smaller in people with fibromyalgia.
• Painkillers: use of opioids after surgery did not differ.

Limits of the Study

• The group with fibromyalgia was small (54 people), so smaller differences could have gone unnoticed.
• Only 43% of patients had weight data at two years. Only 23% had quality-of-life data.
• Registers show diagnoses and prescriptions, not how people felt day to day.
• The study did not measure whether fibromyalgia symptoms such as pain or fatigue changed after surgery.
• All participants were women.

What This Means for You

This is one of the first studies on this question. It gives no sign that fibromyalgia makes surgery riskier, and weight loss was similar. The smaller quality-of-life gain after one year is worth discussing with your care team, so that expectations are realistic and aftercare fits your situation. The authors say the study cannot rule out meaningful differences.

If you are considering surgery, discuss it with your physician and the surgical team. Tell them about your fibromyalgia, your pain medication and your sleep, so they can plan around it.