Evaluation of intravenous zoledronic acid-induced acute-phase response in the emergency department

Abstract

Background/Aim: A temporary influenza-like condition, called acute-phase reaction (APR), is commonly observed with intravenous (IV) administration of nitrogen-containing amino bisphosphonates, such as zoledronic acid (ZOL). This single-center study aimed to evaluate the incidence of APR symptoms after intravenous (IV) ZOL administration in patients with postmenopausal osteoporosis who were admitted to emergency department (ED).
 Methods: In this cross-sectional study, 107 osteoporotic patients who were diagnosed with post-menopausal osteoporosis (bone mineral density T-score equal to or below −2.5 with/without prevalent fractures) and who had an ED admission in the first 72 h after intravenous injection of ZOL were included in the study. The patient’s pre-treatment blood sample measurements, presenting symptoms (such as fever, fatigue, hyperpyrexia, headache), family history, previous medical treatment, and adverse effects caused by osteoporosis drugs, in addition to information on co-morbidities and comedications were obtained from clinical records.
 Results: One-hundred seven osteoporotic patients (19.56%) patients experienced APR and were admitted to the ED after IV-ZOL administration. The mean age was 64.58 (11.15) years (n = 107). The three most commonly reported symptoms were diffuse musculoskeletal symptoms, influenza-like illness, and gastrointestinal symptoms (34.5%, 21.5%, and 18.5%, respectively). Seventy percent of the patients who presented to the ED with APR symptoms were prescribed drugs only, and 30% of the patients received treatment specific for their symptoms in the ED. Most of the diffuse musculoskeletal symptoms consisted of myalgia (22.4%). A positive correlation between the onset time of APR symptoms and the number of IV bisphosphonate (BP) doses was found (r = 0.597; P = 0.032).
 Conclusion: Our study indicates that as the number of IV-ZOL administrations increase yearly in patients with osteoporosis, symptom onset time occurs later. A linear relationship was found between the number of drug applications and the duration of symptoms. Also, the incidence of APR following IV-ZOL administration was 19% in the osteoporotic patient population who presented to the ED or to other clinics according to the symptoms.