The Effects of Polyphenols on Bone Metabolism in Postmenopausal Women: Systematic Review and Meta-Analysis of Randomized Control Trials.

Osteoporosis is a condition favored by the postmenopausal decline in estrogen levels and worsened by oxidative stress (OS). Polyphenols are natural compounds abundantly found in fruits and vegetables, and they exert antioxidant and hormonal effects that could be useful in osteoporosis prevention, as suggested by epidemiological studies showing a lower incidence of fractures in individuals consuming polyphenol-rich diets. The aim of our meta-analysis is to evaluate the effects of polyphenols on bone mineral density (BMD, primary endpoint) and bone turnover markers (BTMs, secondary endpoint) in postmenopausal women. Twenty-one randomized control trials (RCTs) were included in our analysis after in-depth search on PubMed, EMBASE, and Scopus databases. We found that supplementation with polyphenols for 3-36 months exerted no statically significant effects on BMD measured at lumbar spine (sMD: 0.21, 95% CI [-0.08 to 0.51], p = 0.16), femoral neck (sMD: 0.16, 95% CI [-0.23 to 0.55], p = 0.42), total hip (sMD: 0.05, 95% CI [-0.14 to 0.24], p = 0.61), and whole body (sMD: -0.12, 95% CI [-0.42 to 0.17], p = 0.41). Subgroup analysis based on treatment duration showed no statistical significance, but a significant effect on lumbar BMD emerged when studies with duration of 24 months or greater were analyzed separately. On the other hand, we found a significantly slight increase in bone-specific alkaline phosphatase (BALP) levels (sMD: 1.27, 95% CI [1.13 to 1.42], p < 0.0001) and a decrease in pyridinoline (PD) levels (sMD: -0.58, 95% CI [-0.77 to -0.39], p < 0.0001). High heterogeneity among studies and unclear risk of bias in one third of the included studies emerged. A subgroup analysis showed similar effects for different duration of treatment and models of dual-energy X-ray absorptiometry (DXA) scanner. More robust evidence is needed before recommending the prescription of polyphenols in clinical practice.

Remote management of osteoporosis in the first wave of the COVID-19 pandemic.

We conducted a survey during the first pandemic wave of coronavirus disease 2019 (COVID-19) on a large group of osteoporotic patients to evaluate the general conditions of osteoporotic patients and the impact of the pandemic on the management of osteoporosis, finding high compliance to treatments and low COVID-19 lethality. INTRODUCTION: During the first pandemic wave of coronavirus disease 2019 (COVID-19), 209,254 cases were diagnosed in Italy; fatalities were 26,892 and were overwhelmingly older patients. The high prevalence of osteoporosis in this age group suggests a potential relationship between SARS-CoV-2 infection and bone metabolism. METHODS: In a telephone survey conducted from April to May 2020, patients from the Osteoporosis Center, Clinic of Endocrinology and Metabolic Diseases of Umberto I Hospital (Ancona, Italy), were interviewed to evaluate the general clinical conditions of osteoporotic patients, compliance with osteoporosis medications, COVID-19 prevalence, hospitalization rate, COVID-19 mortality, and lethality. RESULTS: Among the 892 patients interviewed, 77.9% were taking osteoporosis treatment and 94.6% vitamin D supplementation as prescribed at the last visit. COVID-19-like symptoms were reported by 5.1%, whereas confirmed cases were 1.2%. A total number of 33 patients had been in hospital and the hospitalization rate of those who had not discontinued vitamin D supplementation was less than 4%. There were eight deaths, two with a concomitant COVID-19 diagnosis. The prevalence of severe osteoporosis was 50% in total COVID-19 patients and 87.5% in deceased COVID-19 patients. The overall COVID-19 mortality was 0.2%; lethality was 20%, lower than the national rate of the same age group. CONCLUSIONS: This large group of osteoporotic patients showed high compliance and lower COVID-19 lethality compared to patients of the same age. Novel approaches such as telemedicine can provide critical support for the remote follow-up of patients with chronic diseases also in the setting of routine care.

Bone Metabolism in SARS-CoV-2 Disease: Possible Osteoimmunology and Gender Implications.

Even though inflammatory conditions are known to exert adverse effects on bone metabolism, there are no published data regarding SARS-CoV-2 infection and subsequent fracture risk. We present a brief review of the molecular mechanisms linking inflammatory diseases to increased fracture risk/osteoporosis and of the therapeutic strategies that can prevent bone resorption in patients with inflammatory disease, focusing on the RANK-RANKL system. We also make some considerations on gender differences in infection response and on their implications for survival and for the consequences of COVID-19. Several inflammatory cytokines, especially IL-1, IL-6, and TNF-α, stimulate osteoclast activity, favoring bone resorption through the RANK-RANKL system. Data from the previous SARS-CoV outbreak suggest that the present disease also has the potential to act directly on bone resorption units, although confirmation is clearly needed. Even though the available data are limited, the RANK-RANKL system may provide the best therapeutic target to prevent bone resorption after COVID-19 disease. Vitamin D supplementation in case of deficiency could definitely be beneficial for bone metabolism, as well as for the immune system. Supplementation of vitamin D in case of deficiency could be further advantageous. In COVID-19 patients, it would be useful to measure the bone metabolism markers and vitamin D. Targeting the RANK-RANKL system should be a priority, and denosumab could represent a safe and effective choice. In the near future, every effort should be made to investigate the fracture risk after SARS-CoV-2 infection.