Blood factors as biomarkers in osteoporosis: points from the COVID-19 era

Abstract

The restrictions adopted during the coronavirus disease 2019 (COVID-19) pandemic limiting direct medical consultations and access to healthcare centers reduced the participation of patients with chronic diseases, such as osteoporosis (OP), in screening and monitoring programs. This highlighted the need for new screening diagnostic tools that are clinically effective, but require minimal technical and time commitments, to stratify populations and identify who is more at risk for OP and related complications. This paper provides an overview of the potential use of blood-related factors, such as platelet (PLT)- and monocyte-related factors, as biomarkers able to quickly screen, detect, and monitor OP in both sexes. Such biomarkers might be of key importance not only during the COVID-19 pandemic but also, even more importantly, during periods of better global health stability.

Keywords: COVID-19; monocyte; osteoporosis; platelets; spontaneous osteoclastogenesis.

Figure 1

Schematic representation to perform osteoporosis (OP) screening, diagnosing, and monitoring in the clinical practice using platelet (PLT) count and PLT-related parameters and spontaneous osteoclastogenesis. *Despite that dual-energy X-ray absorptiometry (DXA) is the gold standard in screening and diagnosing OP, not everyone has access to bone density (BMD) testing by DXA [60]. An audit directed by the International Osteoporosis Foundation (IOF) on OP in Asia Pacific found that while Australia, Hong Kong, Japan, New Zealand, Republic of Korea, and Singapore were well resourced with 12–24 DXA machines per million individuals, China, India, Indonesia, Pakistan, Philippines, Sri Lanka, and Vietnam had less than 1 DXA machine per million [61]. Similarly, the IOF, in association with the European Federation of Pharmaceutical Industry Associations (EFPIA), evaluated DXA in the European Union and found that Austria, Belgium, Cyprus, Denmark, Finland, France, Germany, Greece, Italy, Portugal, and Slovenia had at least 11 DXA machines per million, while other countries (i.e., Bulgaria, Czech Republic, Hungary, Latvia, Lithuania, Luxembourg, Poland, Romania, and the United Kingdom) have insufficient DXA provisions [62]. It was also detected that the Latin American countries with the greatest access to DXA were Brazil and Chile, with 10 DXA machines per million, while other countries ranged from 0.9 to 6.7 per million [63].