Today, I’d like to discuss a study that came out of Switzerland and was published in the peer-reviewed periodical Journal of Pain Research in September 2021. The paper is titled: Common and Contrasting Characteristics of the Chronic Soft-Tissue Pain Conditions Fibromyalgia and Lipedema. The authors proposed to compare and contrast two common chronic soft-tissue pain conditions, Lipedema and Fibromyalgia, that did not have a cure. Their hypothesis was that there is a substantial overlap between these two conditions.
This research explores the differences and similarities between the two chronic soft-tissue pain conditions to further understand and improve their diagnosis and treatment.
What methods did the authors use?
This study used both a literature review and assessments of the enrolled participants. First, the literature was searched for clinical descriptions of these two disorders. This helped the researchers not only understand each disorder but also assemble a case definition that would assign participants either to the lipedema or fibromyalgia group.
Here are the measurements that were used in this study to assess the enrolled participants:
- Short Form 36 (SF-36), is a self-report survey in 8 areas including questions about physical functioning, pain, general health, vitality, social functioning, and mental health.
- 6-minute Walking Distance (6MWD) test, which is a measure of the distance walked in 6 minutes.
- Fibromyalgia Severity Questionnaire (FSQ), was used to confirm a diagnosis of fibromyalgia and inclusion in that group. If the participant also had a diagnosis of lipedema, she was included in the lipedema group and listed as having comorbidity of fibromyalgia.
Who participated in the study?
The participants in this study were all female, with 77 in the fibromyalgia group and 112 in the lipedema group. They were all assessed either in the Zurzach Interdisciplinary Pain Program, which is an inpatient hospital setting, or the Angiology department of the Rehaklinik Bad Zurzach, which is an outpatient consultation. This consultation could lead to a referral to the inpatient Pain Program or continue with outpatient treatment at the Rehaklinik. 100% of the fibromyalgia group and just over 36% of the lipedema participants were then admitted to inpatient treatment in this study.
What are their differences and similarities?
Here are some of the differences between the two groups that were observed. The women enrolled in the fibromyalgia group were, on average, a little older than the women in the lipedema group, at 49 years versus 45 years. The fibromyalgia group was also less likely to be obese, with a BMI of 27, which is considered overweight, versus a BMI of almost 34 in the lipedema group, which is considered obese. Obesity was much more prevalent in the lipedema group at 88%, while just 33% of the women in the fibromyalgia group were obese. (It should be noted that BMI, which is a calculation based on weight and height, is a very poor indicator of obesity for lipedema. Bioimpedance, which shows the percent body fat, is a much better measure).
More women in the fibromyalgia group tended to smoke, be less active, and have more comorbidities than the women in the lipedema group. The women in the fibromyalgia group also spent fewer hours working outside of the home.
In other areas, the Lipedema and Fibromyalgia groups were very similar. These included the percentage that lived alone or with others, their education level, and hours spent working in the household.
What authors found in the literature review
These are some of the findings in the literature review:
Both fibromyalgia and lipedema include a symptom of soft tissue pain. They are both diagnosed almost exclusively in women. Obesity and weight management issues, along with depression, are common comorbidities in both groups. Both lipedema and fibromyalgia are considered to be chronic, incurable conditions with very few options for effective treatment.
Both disorders also have a relatively high rate of similar comorbidities, especially depression, fatigue, headache, and obesity. Another commonality between lipedema and fibromyalgia is that these two conditions are commonly misdiagnosed or confused with another condition. Lipedema, especially in the early stages, can be misdiagnosed with other pain conditions, including fibromyalgia. In later stages, lipedema is often confused with obesity and lymphedema. Fibromyalgia is often misdiagnosed with other musculoskeletal pain syndromes such as osteoarthritis.
What authors found in the objective measurements used in the study
The results of the SF-36 self-report survey showed that the participants in the fibromyalgia group had a perception of much lower levels of health and quality of life than those in the lipedema group. This measure uses scores from 0 to 100, with 0 being the worst health and 100 representing the best health. The lowest mean score in the fibromyalgia group was 19.4 for bodily pain. The lipedema group had a much higher mean score of 43.4. The greatest impairment in the lipedema group was in Vitality, rated at 43.3. The mean score for the fibromyalgia group in this category was much lower at 25.8, significantly lower than even the subset of women in the lipedema group that required inpatient treatment.
While all participants in the fibromyalgia group (n=77) took the 6-minute walk distance test, only the women in the lipedema group who were admitted for inpatient treatment were assessed using this test (n=38). Interestingly, despite the significant disparity in self-reported physical functioning on the SF-36 survey, with the fibromyalgia group mean score of 44.9 versus the lipedema group mean score of 68.1, the two groups were almost identical in distances for the 6-minute walk, which was 425 meters for fibromyalgia and 437 meters for lipedema.
The authors report that “although those… lipedema inpatients reported worse health when compared to the whole lipedema group, their scores revealed that they were nonetheless in better health than those with fibromyalgia.”
Another interesting result reported in this paper was that more than a third of the women in the lipedema group also met the diagnostic criteria for fibromyalgia. Additionally, the participants in the fibromyalgia group still experienced much higher pain levels in more diffuse locations than those in the lipedema group. The participants with lipedema reported that their pain was limited to the subcutaneous fat tissue in the affected limbs while the participants with fibromyalgia experienced pain in different types of tissue and usually throughout the body.
Some limitations and conclusions the authors made
The authors reported several limitations to this study. The lipedema group was much larger than the fibromyalgia group (112 vs. 77). Also, only those in the lipedema group that were in the inpatient setting were able to perform the 6-minute walk distance test. Lastly, although most of the lipedema participants were evaluated for fibromyalgia, the fibromyalgia participants were not tested to see if they also had lipedema.
The authors then conclude that although fibromyalgia and lipedema share many characteristics, these are two distinct conditions. Distinguishing fibromyalgia from early-stage lipedema can be especially challenging, but is essential to ensure that appropriate treatments are provided.
This paper is important for women with lipedema because of the similarity of the two conditions. Not only can one disorder be confused with the other, but it is possible to have both conditions which makes an accurate diagnosis and access to appropriate treatment even more challenging. If you believe that your healthcare provider may be having this difficulty in accurately diagnosing you, this may be a good paper to print out and take to them.
For more related content, be sure to check out Lipedema Simplified’s Flash Briefings, our daily mini-podcast with tips, tools, helpful research, and other resources pertaining to lipedema.