POS0949 HIGH PREVALENCE OF ABDOMINAL OBESITY IN FEMALES WITH AXIAL SPONDYLOARTHROPATHY
Authors: Maguire S. , Gallagher P. , Wilson F. , O’shea F. B. 
Published: May 2021

Background:

Worldwide prevalence of obesity has been steadily increasing, despite significant public health campaigns to raise health awareness. In axial spondyloarthropathy (axSpA) obesity has been shown to be associated with higher levels of disease activity and decreased response to treatment. The waist to hip ratio (WtHpR) is a tool to screen for abdominal obesity. Abdominal deposition of adipose tissue is associated with increased risk of cardiovascular disease, type II diabetes and premature death. Abdominal obesity is more commonly found in males, while females are more prone to gluteal-femoral fat deposition. The Ankylosing Spondylitis Registry of Ireland (ASRI) is a source of epidemiological data of axSpA patients in Ireland.

Objectives:

To capture the prevalence of abdominal obesity in a large cohort of axSpA patients and assess for variation in prevalence between sexes.

Methods:

Participants were analysed on the basis of sex and presence of obesity by BMI and WtHpR. Obesity was defined by body mass index (BMI) with a result of >30 categorised as obese as per CDC definitions. Abdominal obesity was assessed by WtHpR and defined as per WHO guidelines. Categorical variables were recorded as frequencies, with a chi2 test for independence used to test for statistical significance. Numerical variables were recorded as means within each group and an independent t-test or Mann Whitney U test was used to test for statistical significance between groups. A p-value of <0.05 was deemed significant. IBM SPSS version 26 was used for statistical analysis of the patient population captured within the ASRI.

Results:

At the time of analysis, physical measurements were available on 692 patients in the ASRI made up of 96.2% (666) Caucasians with 22.3% (154) females and 77.7% (538) males. The average age was 45.9 years with a mean disease duration of 18.8 years (mean scores: BASDAI 4.09, BASFI 3.71, BASMI 3.99, HAQ 0.54, ASQoL 6.72). 80.9% (560) of patients had radiographic sacroiliitis while 49.1% (340) had sacroiliitis on MRI.

Overall 29.5% (215) patients were obese based on BMI results, while 37.5% (274) were centrally obese as per the WtHpR. Analysis on the basis of sex revealed no significant variation in mean BMI (28.1 vs 27.7, p=0.45) or prevalence of obesity as assessed by BMI (29.9% vs 28.6%, p=0.49) between males and females(table 1). As expected analysis of WtHpR revealed higher mean ratios in males compared to females (0.96 vs 0.89, p<0.01), however there was a significantly higher prevalence of abdominal obesity in females (29.9% vs 68.2%, p<0.01).

Table 1.

Assessment of Obesity by Sex

MalesFemalesp valuen77.7% (538)22.3% (154)Weight (kg)84.9872.76<0.01BMI28.0827.690.45Underweight0.9% (5)0.06% (1)0.49Normal Weight29.2% (157)36.4% (56)Overweight39.2% (211)34.4% (53)Obese29.9% (161)28.6% (44)Waist Circumference (cm)97.4390.03<0.01Hip Circumference (cm)102.11101.270.56Waist to Hip Ratio0.9560.8901<0.01Normal Weight23.8% (128)17.5% (27)<0.01Overweight46.3% (249)14.3% (22)Obese29.9% (161)68.2% (105)

Conclusion:

There is a high prevalence of abdominal obesity as assessed by WtHpR in axSpA, this is especially high in females with axSpA. Use of WtHpR should be considered when screening for obesity in this population.

Disclosure of Interests:

Sinead Maguire Grant/research support from: Recipient of the Gilead Inflammation fellowship grant, Phil Gallagher: None declared, Fiona Wilson: None declared, Finbar Barry O’Shea: None declared