Prevalence of Metabolic Syndrome in a Sample of Iraqi Patients with Ankylosing Spondylitis treated with Anti TNF-a Therapy

Abstract

Ankylosing  spondylitis  (AS)  is  a  chronic  inflammatory  rheumatic disease,  which  mainly  affects  the  axial  joints,  including  the  spine, sacroiliac joints, and entheses.  The aim of the study was to detect the prevalence of metabolic syndrome (MetS) in Iraqi patients with AS, in comparison to healthy controls and to assess their relationships with demographic and clinical characteristics. A cross-sectional study was conducted at the rheumatology unit of Baghdad Teaching Hospital in Medical City from October 2019 to March 2020.The study included a total of 100 patients diagnosed with AS, according to the modified New York  diagnostic  criteria,  and  100  age  and  sex  matched  controls. Demographic  data,  disease  activity  scores,  comorbidities,  current medications were reported. Waist circumference, blood pressure, fasting blood sugar, triglyceride and high-density lipoprotein cholesterol were measured  and  MetS  was  diagnosed  according  to  the  NCEP  ATPIII criteria. The prevalence of MetS in AS patients was (51%) which is higher  than  that  of  the  controls  (46%),  but  the  difference  was insignificant  (p=0.4).  The  mean  HDL-c,  FBS,  systolic  and  diastolic blood  pressure  were significantly  lower  in  AS  patients compared to controls (p=0.03; p=0.005; p=0.05; p=0.01, respectively). AS patients with MetS had significantly higher incidence of low HDL-c (P=0.03), and  lower  incidence  of  high  FBS  (P=0.01)  and  TG  (P=0.04)  than controls with MetS. The mean age and body mass index in patients with AS and MetS were significantly higher compared to patients with AS without  MetS  (p=0.005;  p=0.001).  Multivariate  regression  analysis showed that age of the patients was the only significant predictor for the risk of MetS (odds ratio [OR] =1.6, confidence interval [95% CI] = 1.2 - 1.8,  P=0.03).  It  was  concluded  that,  the  prevalence  of  metabolic syndrome in AS patients was higher than in the general population but statistically insignificant. Low HDL-c is the most important component of MetS in AS. AS patients with MetS were older in age and had higher BMI than AS without MetS.