# Temporal trends of all-cause mortality in Paget’s disease of bone: a population-based retrospective cohort study over 20 yr

## TL;DR

This study shows that mortality in people with Paget’s disease of bone increased over 20 years, while it decreased in the general population.

## Contribution

The study provides new insights into the changing mortality risk in Paget’s disease compared to the general population over two decades.

## Key findings

- All-cause mortality in PDB patients increased from 47.1/1000 to 54.2/1000 over 20 years.
- Mortality in the general population decreased from 27.6/1000 to 22.3/1000 during the same period.
- The adjusted relative risk of mortality in PDB patients increased from 1.06 to 1.16 compared to the general population.

## Abstract

Paget's disease of bone (PDB) is a focal, late-onset, chronic disorder of bone metabolism. Although the prevalence of PDB is stable in Quebec, the incidence and clinical severity of PDB have decreased over time. In this study, we determined the temporal trend of mortality associated with PDB in a large population-based retrospective cohort over 20 yr from the medico-administrative data of the Régie de l'assurance maladie du Québec, compared with the general population. For each fiscal year, the age-standardized rate of all-cause mortality was determined from 2000/2001 to 2020/2021 in individuals aged ≥55 with PDB and in the general population. The population size was 1 706 015 in 2000/2001 and 2 913 820 in 2019/2020. The case definition was based on 1 hospitalization or 2 claims from physicians with the diagnosis code of PDB. We determined the adjusted relative risk (aRR) of mortality in men and women, as well as by age categories. A total of 99% CIs have been calculated. We described the percentage of death for each main cause of death. Between 2000-2001 and 2020/2021, the all-cause age-standardized mortality rate (ASMR) in PDB individuals significantly increased from 47.1/1000 to 54.2/1000, respectively (JoinPoint analysis p < .01). The all-cause ASMR significantly decreased from 27.6/1000 to 22.3/1000 in the general population (JoinPoint analysis p < .01), respectively. Over the study period, compared with the general population, the PDB aRR of mortality rate has increased from 1.06 (0.95-1.19) to 1.16 (1.06-1.27), with a significant increase of mortality observed between 2016/2017 and 2019/2020. We observed an increase in the aRR of mortality in the age category of 65-74 yr from 1.15 (0.84-1.57) to 1.26 (0.97-1.64). The increased mortality in the endocrine and cardiovascular systems may be related to the aging of the pagetic cohort but also to the presence of vascular calcifications.