Prevalence of chronic chikungunya and associated risks factors in the French West Indies (La Martinique). A prospective cohort study

Abstract

50Background 51 The chikungunya virus (CHIKV) is a re-emerging alphavirus that can cause chronic rheumatic 52 musculoskeletal disorders, named chronic chikungunya (CHIKC+), which may be long-term 53 incapacitating. A chikungunya outbreak occurred in 2013 in La Martinique. We constituted the first 54 prospective cohort study of CHIKV-infected subjects in the Caribbean to assess the prevalence of 55 CHIKC+ at 12 months and to search for factors present at the acute stage significantly associated with 56 chronicity. 57 58 Methodology/Principal findings 59 A total of 193 patients who tested positive for RT-PCR CHIKV, were submitted to clinical 60 investigations in the acute phase (<21 days), and 3, 6, and 12 months after their inclusion. A total of 61 167 participants could be classified as either suffering or not from CHIKC+. They were analyzed using 62 logistic regression models. At 12 months, the overall prevalence of CHIKC+ was 52.1% (95%CI: 44.5-63 59.7). In univariate analysis, age (OR: 1.04; 95% CI: 1.02-1.07; p=0.0003), being male (OR: 0.51; 64 95%CI: 0.27-0.98; p=0.04), headache (OR: 1.90; 95%CI: 1.02-3.56; p=0.04), vertigo (OR: 2.06; 95%CI: 65 1.05-4.03; p=0.04), vomiting (OR: 2.51; 95%CI: 1.07-5.87; p = 0.03), urea (OR: 1.33; 95%CI: 1.05-1.70; 66 p=0.02) were associated with CHIKC+. In final multivariate logistic regression models for 167 67 participants, predictors of CHIKC+ were age (OR 1.06; 95%CI: 1.03-1.08; p<0.0001), male sex (OR: 68 0.40; 95%CI: 0.19-0.84; p=0.015), vertigo (OR: 2.46; 95%CI: 1.16-5.20; p=0.019), hypotension (OR 69 4.72; 95% -CI: 1.19-18.79; p=0.028), recoloration time >3 seconds (OR: 3.79; 95%-CI: 1.01-14.25). 70 71