Adipose tissue distribution is associated with cardio-metabolic alterations in adult patients with juvenile-onset dermatomyositis.

OBJECTIVES: Primary aims were to compare adipose tissue distribution in adult patients with juvenile-onset DM (JDM), with matched controls. Secondary aims were to explore how adipose tissue distribution is associated with cardio-metabolic status (cardiac dysfunction and metabolic syndrome) in patients. METHODS: Thirty-nine JDM patients (all aged ≥18 y, mean age 31.7 y and 51% female) were examined mean 22.7 y (s.d. 8.9 y) after disease onset and compared with 39 age/sex-matched controls. In patients, disease activity and lipodystrophy were assessed by validated tools and use of prednisolone noted. In all participants, dual-energy X-ray absorptiometry (DXA) and echocardiography were used to measure visceral adipose tissue (VAT)(g) and cardiac function, respectively. Risk factors for metabolic syndrome were measured and associations with adipose tissue distribution explored. For primary and secondary aims, respectively, P-values ≤0.05 and ≤0.01 were considered significant. RESULTS: Patients exhibited a 2.4-fold increase in VAT, and reduced HDL-cholesterol values compared with controls (P-values ≤ 0.05). Metabolic syndrome was found in 25.7% of the patients and none of the controls. Cardiac dysfunction (systolic and/or diastolic) was found in 23.7% of patients and 8.1% of controls (P = 0.07). In patients, VAT levels were correlated with age, disease duration and occurrence of metabolic syndrome and cardiac dysfunction. Occurrence of lipodystrophy (P = 0.02) and male sex (P = 0.04) tended to be independently associated with cardiac dysfunction. CONCLUSION: Adults with JDM showed more central adiposity and cardio-metabolic alterations than controls. Further, VAT was found increased with disease duration, which was associated with development of cardio-metabolic syndrome.

Assessment of Microvascular Abnormalities by Nailfold Capillaroscopy in Juvenile Dermatomyositis After Medium- to Long-Term Followup.

OBJECTIVE: In juvenile dermatomyositis (DM), microvascular abnormalities, measured by nailfold capillaroscopy (NFC), are common early in the disease course. We aimed to compare the presence of NFC abnormalities in patients with medium- to long-term juvenile DM with that of controls, and to explore associations between NFC abnormalities and disease activity and other disease characteristics. METHODS: Fifty-eight juvenile DM patients with a median disease duration of 16.8 (range 2-38) years were clinically examined and compared with matched controls. By NFC, we assessed nailfold capillary density (NCD), giant capillaries, scleroderma, and neovascular pattern (defined as scleroderma active or late pattern). NFC was analyzed with researchers blinded to patient/control identity and disease characteristics. We measured disease activity and damage by validated tools, and patients were categorized as having active or inactive disease according to the Paediatric Rheumatology International Trials Organisation criteria. RESULTS: Compared to controls, patients had decreased NCD (mean ± SD 6.4 ± 2.1/mm versus 7.6 ± 0.8/mm; P = 0.001) and showed more abnormality in all other NFC parameters; 36% of patients versus 4% of controls had NCD <6/mm (P < 0.001). Giant capillaries, scleroderma, and neovascular pattern were found in 9%, 84%, and 41% of patients, respectively. Patients with active disease (n = 30) presented more frequently with neovascular pattern than patients with inactive disease (n = 28) (P = 0.041). Decreased NCD and neovascular pattern were associated with higher levels of disease activity and impaired muscle function. CONCLUSION: After medium- to long-term followup, juvenile DM patients had decreased NCD and, often, neovascular pattern; both were associated with higher levels of disease activity and impaired muscle function. This suggests that NFC can be a biomarker for disease activity in longstanding juvenile DM too.