Muscle strength and functional exercise capacity in patients with lipoedema and obesity: a comparative study

Background: Lipoedema is a chronic disorder of adipose tissue typically involving an abnormal build-up of fat cells in the legs, thighs and buttocks. Occurring almost exclusively in women, it often co-exists with obesity. Due to an absence of clear objective diagnostic criteria, lipoedema is frequently misdiagnosed as obesity, lymphoedema or a combination of both. The purpose of this observational study was to compare muscle strength and exercise capacity in patients with lipoedema and obesity, and to use the findings to help distinguish between lipoedema and obesity. Design: This cross-sectional, comparative pilot study performed in the Dutch Expertise Centre of Lymphovascular Medicine, Drachten, a secondary-care facility, included 44 women aged 18 years or older with lipoedema and obesity. Twenty-two women with lipoedema (diagnosed according the criteria of Wold et al, 1951) and 22 women with body mass index ≥30kg/m2 (obesity) were include in the study. No interventions were undertaken as part of the study. Results: Muscle strength of the quadriceps was measured with the MicroFET™, and functional exercise capacity was measured with the 6-minute walk test. The group with lipoedema had, for both legs, significantly lower muscle strength (left: 259.9 Newtons [N]; right: 269.7 N; p < 0.001) than the group with obesity. The group with lipoedema had a non-significant, but clinically relevant lower exercise-endurance capacity (494.1±116.0 metres) than the group with obesity (523.9±62.9 metres; p=0.296). Conclusions: Patients with lipoedema exhibit muscle weakness in the quadriceps. This finding provides a potential new criterion for differentiating lipoedema from obesity. We recommend adding measuring of muscle strength and physical endurance to create an extra diagnostic parameter when assessing for lipoedema.