Leech therapy in symptomatic treatment of fibromyalgia: results of a pilot study
Bäcker M, Lüdtke R, Afra D, Cesur Ö, Langhorst J, Fink M, Dobos GJ, Michalsen A (2011) · Forschende Komplementärmedizin · n=14
RCT evidence detailTrial reference
Study Profile
- Design
- single-center, open-label pilot study (Essen)
- Sample size (n)
- 14
- Intervention
- Two sessions of 4-7 Hirudo medicinalis leeches at trigger-point sites, 14 days apart
- Comparator
- No control arm — pilot single-arm design with within-subject pre-post comparison
- Primary endpoint
- Fibromyalgia Impact Questionnaire (FIQ) total score at day 28
- Primary result
- FIQ total score dropped from 60.1 to 41.3 at day 28 (-31%, p<0.001); pain VAS from 65 to 38mm (-42%)
- Effect size (Cohen's d)
- 0.92
- Follow-up duration
- 3 months
Key Findings
- Within-subject FIQ reduction of 31% over 28 days in a notoriously refractory condition
- Pain VAS, fatigue, and tender point count all improved significantly
- Effect partially sustained through 3-month follow-up
- First study exploring leech application at multiple trigger-point sites rather than single joint
- Patient-rated tolerability high — all 14 patients completed protocol
Limitations
- No control arm — entire effect could reflect natural fluctuation, placebo, or attention
- Very small sample (n=14)
- Open-label
- Single site
- Fibromyalgia diagnosis based on 1990 ACR criteria — superseded by 2010/2016 criteria
Clinical Implications
Bäcker 2011 is best understood as a Phase-I-style exploratory signal rather than a definitive trial. The within-subject changes are large but uncontrolled. The trial's principal contribution is demonstrating that multi-site leech application is feasible and tolerable in fibromyalgia patients, paving the way for future controlled designs. Clinicians should not cite this trial as evidence for fibromyalgia efficacy but may reference it when discussing exploratory uses with motivated patients seeking non-pharmacologic options.