Denosumab utilization among older adults in Ontario: patient characteristics, persistence with therapy, and return to therapy after an extended gap.

We studied 46,797 older adults who initiated denosumab in Ontario, Canada. Patient characteristics remained relatively stable over time and aligned with public reimbursement restrictions. Almost half of patients persisted with therapy for at least 3 years. Fifty-nine percent of patients who discontinued denosumab returned to treatment within 3.6 years. INTRODUCTION: The purpose of this study was to describe the characteristics of patients who initiated denosumab and estimate persistence with therapy. METHODS: We identified older adults (aged ≥ 66 years) in Ontario who initiated denosumab between 2012/02 and 2015/03 and followed them to 2016/03. Patient characteristics were summarized using medical and pharmacy claims in the year before starting denosumab and osteoporosis drug use considered since 1996/10. Persistence with denosumab and return after discontinuation (> 90-day gap) were estimated using Kaplan-Meier curves. Analyses were stratified by community and long-term care (LTC) residence. RESULTS: We identified 46,797 patients (monthly mean = 1263, SD = 187); 97% female, 13% LTC. Community-dwelling patients had a higher prevalence of bone mineral density testing (62% vs. 5%), yet were younger (mean age 78.5 vs. 86.6 years) and had lower prevalence of hip fractures (3% vs. 10%) compared to LTC patients. Eighty-two percent of patients had used osteoporosis medications in the past; 99% of whom took an oral bisphosphonate. Persistence was similar between community-dwelling and LTC patients: 59% persisted ≥ 2 years, 48% ≥ 3 years, and 38% ≥ 4 years, yet a larger proportion of LTC patients returned to denosumab after discontinuation (76% vs. 57%). CONCLUSIONS: Denosumab utilization is increasing at a steady rate in Ontario. However, persistence remains a concern given the highly reversible pharmacokinetic profile of denosumab that results in a rapid increased fracture risk following discontinuation. Over 80% of patients had a history of oral bisphosphonate therapy, which may persist in bone despite discontinuing denosumab. Consequently, better understanding of denosumab safety and effectiveness among real-world users is important.

Contributions of polymorphisms in miR146a, miR196a, and miR499 to the development of hepatocellular carcinoma.

Hepatocellular carcinoma is one of the most common malignant tumors worldwide; it is estimated that there were 782,000 new cases in 2012. MicroRNAs (miRNAs) play an important role in carcinogenesis by regulating oncogenes and tumor suppressors. We investigated the role of miR-146a, miR-196a2, and miR-499 polymorphisms in the risk of hepatocellular carcinoma in a Chinese population. Hepatocellular carcinoma patients (175) and healthy controls (302) were recruited between April 2013 and March 2015. Genotype analysis of miR-146a, miR-196a2, and miR-499 polymorphisms was carried out by polymerase chain reaction-restriction fragment length polymorphism. There was a significant difference between the genotype distribution of miR-196a2 in hepatocellular carcinoma patients and controls (X2 = 17.23, P < 0.001). CG and GG miR-146a genotypes significantly elevated the risk of hepatocellular carcinoma compared with the CC genotype, with adjusted ORs (95%CI) of 3.05 (1.07-8.70) and 4.96 (1.64-14.97), respectively. In the recessive model, the CG + GG genotype had a 3.75-fold risk of hepatocellular carcinoma compared with the CC genotype, with an adjusted OR (95%CI) of 3.75 (1.39-10.11). However, no significant association was observed between miR-196a2 and miR-499 variants and risk of hepatocellular carcinoma in the co-dominant, dominant, and recessive models. The miR-146a polymorphism is a G to C substitution that causes a mismatch in the stem-loop of miRNA, which influences how the expression and transcriptional regulation of miRNA affects its target genes. Our study revealed that the GG and CG genotypes of miR-146a increased the risk of hepatocellular carcinoma in the Chinese population.

Pollen limitation and Allee effect related to population size and sex ratio in the endangered Ottelia acuminata (Hydrocharitaceae): implications for conservation and reintroduction.

Small populations may suffer more severe pollen limitation and result in Allee effects. Sex ratio may also affect pollination and reproduction success in dioecious species, which is always overlooked when performing conservation and reintroduction tasks. In this study, we investigated whether and how population size and sex ratio affected pollen limitation and reproduction in the endangered Ottelia acuminata, a dioecious submerged species. We established experimental plots with increasing population size and male sex ratio. We observed insect visitation, estimated pollen limitation by hand-pollinations and counted fruit set and seed production per fruit. Fruit set and seed production decreased significantly in small populations due to pollinator scarcity and thus suffered more severe pollen limitation. Although frequently visited, female-biased larger populations also suffered severe pollen limitation due to few effective visits and insufficient pollen availability. Rising male ratio enhanced pollination service and hence reproduction. Unexpectedly, pollinator preferences did not cause reduced reproduction in male-biased populations because of high pollen availability. However, reproductive outputs showed more variability in severe male-biased populations. Our results revealed two component Allee effects in fruit set and seed production, mediated by pollen limitation in O. acuminata. Moreover, reproduction decreased significantly in larger female-biased populations, increasing the risk of an Allee effect.