Osteoporotic patients treated with bisphosphonates do not show the increased mortality observed in those untreated

Abstract

Introduction: Osteoporosis has been said to be associated with increased mortality. On the other hand, it is debated whether treatment with bisphosphonates may reduce mortality in osteoporotic patients. To contribute to the clarification of these issues, we have studied in a prospective cohort the mortality in people without osteoporosis and in patients with osteoporosis, untreated or treated with bisphosphonates MATERIAL AND Methods: At their inclusion in the cohort, four groups of participants were identified: (a) people without osteoporosis (group 1); (b) osteoporotic patients treated with bisphosphonates (group 2); (c) osteoporotic patients who refused to be treated (group 3); and (d) patients who met osteoporosis diagnostic criteria but were not treated because their risk of fracture was considered to be low (group 4). To compare all four groups, unadjusted Kaplan-Meier estimates of survivorship were obtained and they were compared using log-rank test. Hazard ratios were then estimated via Cox regression adjusting for the main confounders. A comparison among the osteoporotic groups was made by means of a Cox regression analysis performed using only these three groups, adjusting for propensity scores. Results: Two thousand six hundred and sixty-five people were included. In the unadjusted analysis, mortality in group 3 was higher than in the other groups (p < 0.001). Taking group 1 as a reference, Cox regression analysis showed the following mortality HRs for groups 2, 3, and 4 after adjusting for confounding factors: 0.82 (0.41-1.63), 1.37 (0.90-2.10), and 0.69 (0.46-1.02). In the analysis of the osteoporotic groups with the PS generated for them, and taking group 2 as a reference, the HRs were as follows: group 3, 2.38 (1.34-4.22); group 4, 1.45 (0.61-3.43). Conclusion: Mortality in osteoporotic patients who refused treatment is higher than in osteoporotic patients treated with bisphosphonates. In unadjusted analysis, it was also higher than in non-osteoporotic people; however, this difference disappeared after adjustment for confounding factors.