Page 228 - Haematologica April 2020

S. Thorsteinsdottir et al.
significant as the interaction effect of a fracture and calen- dar period was significant for 2000-2013 compared to 1990-1999 (HR=0.85; 95%CI: 0.77-0.93; P<0.01). When outpatient diagnoses of fractures were excluded, HR for 2000-2013 was 2.08 (95%CI: 1.94-2.23), HR for 1990-1999 was 2.29 (95%CI: 2.13-2.46), and the difference between the calendar periods was no longer significant (0.99; 95%CI: 0.90-1.09; P=0.91). When the association of frac- tures and death after MM diagnosis was assessed for the two calendar periods after year 2000, HR for 2000-2006 was 1.72 (95%CI: 1.59-1.87), and HR for 2007-2013 was 1.97 (95%CI: 1.77-2.20).
Effect of fracture on survival in matched controls
A total of 53,154 matched controls were included in the study, and 9,897 (18.6%) developed a fracture during the follow up. The median follow up for all controls was 6.8 years. The risk of death was increased for controls who developed a fracture after the time of MM diagnosis in the corresponding MM case as compared to controls without a fracture (HR=2.02; 95%CI: 1.95-2.08) for all fractures combined. The risk of death was increased for controls who developed a vertebral (HR=2.01; 95%CI: 1.88-2.15), femoral (2.17; 1.92-2.45), humerus (1.66; 95%CI: 1.54- 1.79), and rib (1.62; 95%CI: 1.48-1.78) fracture.
Figure 2. Fracture-free survival in mul- tiple myeloma (MM) patients after MM diagnosis.
Figure 3. Landmark analysis showing survival probability in patients with and without a fracture during the first six months after multiple myeloma (MM) diagnosis.
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