Perfil inflamatório de indivíduos com distrofia muscular de Duchenne: relações entre parâmetros bioquímicos e nutricionais

Abstract

Introduction: Duchenne Muscular Dystrophy (DMD) is the most frequent dystrophy. Chronic inflammation appears as an important feature of DMD pathophysiology and progression, with cytokines being biomarkers of systemic inflammation and indicative of muscle damage in DMD. Objective: To identify the inflammatory profile of individuals with DMD and to evaluate associations between biochemical and nutritional variables. Methods: a prospective observational study was conducted with data collection between January 2018 and June 2019, in the city of Natal, Northeastern Brazil. Male patients with confirmed diagnosis of DMD were included. Sociodemographic and disease duration data were obtained by interview; the use of medications was assessed based on information from the patient's medical record; the nutritional status was assessed according to the body mass index (BMI) and the body composition determined with the aid of dual emission x-ray densitometry (DXA). Plasma cytokines IL-1β, IL-6, and TNF-𝛼 were measured using the Enzyme Linked Immunosorbente Assay (ELISA) test. The relationship between disease duration, nutritional status, body composition and cytokines was assessed by the Wilcoxon test. Spearman's correlation coefficient and multiple linear regressions were used to establish the relationship between the time of the first signs of DMD, fat mass (FM) and cytokines. Results: 44 individuals aged 4.3 to 24.2 years were evaluated. At the time of data collection, individuals had been for 7.8 (4.7–10.5) years since the onset of the first signs of the disease. Concerning BMI, 18.2% of the individuals presented marked thinness, thinness or underweight, 40.9% were eutrophic, and 40.9% presented risk of overweight, overweight, or obesity. The mean %FM was of 33,9 (15,9–50,2) %. The %FM increased (p <0.001) since the beginning of the first signs of DMD. The time of disease was positively correlated with IL-6 (ρ = 0.371 p = 0.013). BMI/Age correlated negatively with IL-1β and TNF-α (ρ = -0.357 p = 0.030 and ρ = -0.353 p = 0.032), while the %MG showed a negative relationship with TNF-α (ρ = - 0.435 p = 0.005). The regression models demonstrated lower z-scores of BMI/A associated with higher values of IL-1β (β = -0,498 p = 0,003) and IL-6 (β = - 0.640 p = 0.004), higher %FM associated positively with IL-6 (β = 0.582 p = 0.007) and negatively with TNF-α (β = -0.415 p = 0.015). Conclusion: A persistent inflammatory profile was observed in the patients evaluated. The disease duration was not a predictor for the values of the evaluated cytokines. Lower values of BMI/A and higher values of %FM were predictors of higher concentrations of IL-6, while lower values of %FM were associated with higher production of TNF-α. The data suggest that maintaining adequate nutritional status and body composition are important for determining the inflammation presented by individuals with DMD.