title: Leukocyte Activation in Obese Patients: Effect of Bariatric Surgery.
abstract: The rising prevalence of obesity is a major global health problem. In severe obesity, bariatric surgery (BS) allows to obtain a significant weight loss and comorbidities improvement, among them one of the factors is the thrombotic risk. In this observational study, we measured indices of leukocyte activation in severely obese patients as markers of increased thrombotic risk in relation with serum markers of inflammation before and after BS. Frequency of polymorphonuclear neutrophil-platelet (PLT) and monocyte (MONO)-PLT aggregates as well as of tissue factor (TF) expressing MONOs was measured in the peripheral blood of 58 consecutive obese patients and 30 healthy controls. In 31 of the 58 obese patients, data obtained at the enrollment were compared with those obtained at 3, 6, and 12 months after BS. Compared with healthy controls, obese patients showed a higher frequency of polymorphonuclear leukocyte (PMNL)-PLT aggregates (7.47 ± 2.45 [6.82-8.11]% vs 5.85 ± 1.89 [5.14-6.55]%, P = 0.001), MONO-PLT aggregates (12.31 ± 7.33 [10.38-14.24]% vs 8.14 ± 2.22 [7.31-8.97]%, P < 0.001), and TF expressing MONOs (4.01 ± 2.11 [3.45-4.56]% vs 2.64 ± 1.65 [2.02-3.25]%, P = 0.002). PMNL-PLT and MONO-PLT aggregate frequency was positively correlated with TF expressing MONOs (R2 = 0.260, P = 0.049 and R2 = 0.318, P = 0.015, respectively). BS was performed in 31 patients and induced a significant reduction of the body mass index, and waist and hip circumferences. These effects were associated with a significant decrease of PMNL-PLT aggregates at 12 months (7.58 ± 2.27 [6.75-8.42]% vs 4.47 ± 1.11 [3.93-5.01]%, P < 0.001), and a reduction of TF expressing MONOs at 6 (3.82 ± 2.04 [3.07-4.57]% vs 1.60 ± 1.69 [0.30-2.90]%, P = 0.008) and 12 months (3.82 ± 2.04 [3.07-4.57]% vs 1.71 ± 0.54 [1.45-1.97]%, P = 0.001) after BS.These data suggest that leukocyte-PLT aggregate formation and MONO activation represent an important mechanism underlying the increased thrombotic risk of obese patients. We also show that BS is effective in normalizing these inflammatory indices.
authors.affiliation: From the Institute of Internal Medicine and Geriatrics (DM, DG, MAN, AC, MF, CG, LDG, GM, RL); and Institute of Obstetrics and Gynaecology (AF), Catholic University School of Medicine, Rome, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Minervino
authors.forename: Daniela
authors.initials: D
authors.lastname: Gumiero
authors.forename: Maria Anna
authors.initials: MA
authors.lastname: Nicolazzi
authors.forename: Annamaria
authors.initials: A
authors.lastname: Carnicelli
authors.forename: Mariella
authors.initials: M
authors.lastname: Fuorlo
authors.forename: Caterina
authors.initials: C
authors.lastname: Guidone
authors.forename: Leonardo
authors.initials: L
authors.lastname: Di Gennaro
authors.forename: Andrea
authors.initials: A
authors.lastname: Fattorossi
authors.forename: Geltrude
authors.initials: G
authors.lastname: Mingrone
authors.forename: Raffaele
authors.initials: R
authors.lastname: Landolfi
mesh_terms: D000328:Adult; D050110:Bariatric Surgery; D015415:Biomarkers / Q000097:blood*; D001792:Blood Platelets / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000473:pathology*; D009504:Neutrophils / Q000473:pathology*; D009765:Obesity / Q000097:blood* / Q000601:surgery; D010974:Platelet Aggregation; D013927:Thrombosis / Q000209:etiology; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers