Background:
Common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by chronic/recurrent respiratory infections, bronchiectasis, autoimmunity, inflammatory, gastrointestinal diseases and malignancies associated with a chronic inflammatory state and increased risk of osteoporosis and muscle loss.
Aim:
The aim of this study was to evaluate bone mineral density (BMD), body composition and their relationship with lymphocyte subpopulations in CVID patients.
Methods:
Dual-energy X-ray absorptiometry was performed to assess BMD, lean mass, and fat mass in CVID patients. Peripheral blood CD4+, CD8+, and CD19+ cells were measured using flow cytometry.
Results:
Thirty-three patients (37.3 ± 10.8 years old) were examined. Although only 11.8% of the individuals were malnourished
(BMI <18.5 kg/m2), 27.7% of them had low skeletal muscle mass index (SMI), and 57.6% of them had low BMD. Patients with
osteopenia/osteoporosis presented lower weight (p=0.007), lean mass (p=0.011), appendicular lean mass (p=0.011), SMI (p=0.017), and
CD4+ count (p=0.030). Regression models showed a positive association between CD4+ count and bone/muscle parameters, whereas CD19+
B cell count was only associated with muscle variables. Analysis of ROC curves indicated a cutoff value of CD4+ count (657 cells/mm3;
AUC: 0.71, 95% CI 0.52-0.90) which was related to low BMD. Weight (p=0.004), lean mass (p=0.027), appendicular lean mass (p=0.022), SMI
(p=0.029), total bone mineral content (p=0.005), lumbar (p=0.005), femoral neck (p=0.035), and total hip BMD (p<0.001) were found to be
lower in patients with CD4+ count below the cutoff.
Conclusion:
CVID patients presented with low BMD, which was associated with CD4+ count. Moreover, low muscle parameters were correlated with B cell count.