Serum Vitamin D Levels, Disease Activity Score-28 for Rheumatoid Arthritis with C-Reactive Protein (DAS28-CRP), and Cardiac Remodeling Determined by Ventricular Dimensions and Left Atrium Diameter in Patients with Rheumatoid Arthritis: A Prospective Observational Study

BACKGROUND Rheumatoid arthritis (RA) can cause extra-articular manifestations, and the myocardium can be a target. This study aimed to describe structural and functional cardiac echocardiographic variables in RA patients and to evaluate whether vitamin D (VD) levels and inflammation markers, evaluated by Disease Activity Score-28 for Rheumatoid Arthritis with C-reactive protein (DAS28-CRP), are associated with cardiac remodeling (CR) in this population. MATERIAL AND METHODS This prospective observational study evaluated 90 patients with RA in Botucatu University Hospital wards from 2014 to 2017. Clinical data were recorded, including demographic information, comorbidities, length of disease, and treatment type. Serum VD and C-reactive protein levels were measured, and the DAS28-CRP was calculated. A transthoracic echocardiography study was performed. The outcome evaluated was CR. This parameter was assessed by left ventricular geometric patterns and left atrium diameter. RESULTS We evaluated 90 RA patients. The mean age was 52.9±10.8 years, and 17.8% were male. The length of the disease was 96 (60-180) months. Serum VD levels were 30.7±10.4 ng/mL and the DAS28 was 2.7±0.9. Regarding the CR parameters, 56.7% had altered left ventricular geometric patterns and 25.8% had enlargement of left atrium diameter. Even in multivariate analysis, the left ventricular geometric patterns were not associated with the VD levels and the inflammation marker used. However, sufficient VD levels protect from left atrium enlargement (OR: 0.905; IC 95%: 0.843-0.973; P=0.007). CONCLUSIONS Low serum vitamin D values, but not inflammation, are associated with CR in patients with RA.

Pamidronate Attenuates Oxidative Stress and Energetic Metabolism Changes but Worsens Functional Outcomes in Acute Doxorubicin-Induced Cardiotoxicity in Rats

BACKGROUND

Cardiotoxicity is the major side effect of doxorubicin. As mechanisms that are involved in cardiotoxicity are ambiguous, new methods for attenuating cardiotoxicity are needed. Recent studies have shown that bisphosphonates can decrease oxidative stress. Therefore, the objective of this study was to evaluate the effect of pamidronate on preventing acute doxorubicin-induced cardiotoxicity.

METHODS

Sixty-four male Wistar rats were allocated into four groups: the control group (C), the pamidronate group (P), the doxorubicin group (D) and the doxorubicin/pamidronate group (DP). The rats in the P and DP groups received pamidronate injections (3 mg/kg, IP). After 24 hours, the rats in the D and DP groups received doxorubicin injections (20 mg/kg, IP). Forty-eight hours after doxorubicin injection, the rats were killed. Echocardiography, isolated heart study and biochemical analysis were performed.

RESULTS

Doxorubicin-induced acute cardiotoxicity showed increased matrix metalloproteinases (MMP)-2 activation, oxidative damage and induced alterations in myocardial energetic metabolism. Pamidronate did not inhibit MMP-2 activation but attenuated oxidative stress and improved myocardial energetic metabolism. Regarding cardiac function, the DP group exhibited a decrease in the left ventricular ejection fraction in the echocardiography and a decrease in +dP/dt in the isolated heart study compared with other groups. The same DP group presented serum hypocalcaemia.

CONCLUSIONS

Despite its ability to reduce oxidative stress and improve energy metabolism in the heart, pamidronate worsened systolic function in rats treated with doxorubicin, and therefore we cannot recommend its use in conjunction with anthracycline chemotherapy.