Bone fracture in older adults is associated with greater mortality risk, but the location of the break may be a key factor, according to a new study of outcomes in a Danish database.
Over the follow-up period, those with proximal fractures – breaks in the hip, femur, pelvis, rib, clavicle, and humerus – were more likely to be hospitalized and to die, compared with their matched controls, than were those were with distal fractures in regions like the ankle, forearm, hand, or foot, where the mortality was similar to the matched controls.
“Compared with someone with similar comorbidities without a proximal fracture, there seemed to be an increased hospitalization rate for things like diabetes, heart disease, and lung disease, and then for some of those hospitalizations, there seemed to be an increased mortality, compared with people who hadn’t fractured who were hospitalized,” said Jacqueline Center, MBBS, PhD, of the Garvan Institute of Medical Research, Sydney, in an interview. The study abstract was released online by the Endocrine Society. It had been slated for presentation during ENDO 2020, the society's annual meeting, which was canceled because of the COVID-19 pandemic.*
The study included 212,498 women and 95,372 men aged over 50 years who had a fragility fracture between 2001 and 2014. The researchers excluded high-trauma fractures. They matched each fracture patient with four nonfracture patients, based on sex, age, and comorbidity status. There were 30,677 deaths among women over 384,995 person-years of follow-up, and 19,519 deaths in men over 163,482 person-years of follow-up. Women were a mean age of 72 at the time of fracture, while men were a mean age of 75.
The researchers found that proximal fractures were associated with increased risk of mortality, compared with nonfractured controls, with hazard ratios ranging between 1.5 and 4.0. Distal fractures were not associated with any increased mortality risk.
Comorbidities were common in the study population, with 75% of men and 60% of women having at least one. The risk of mortality increased with increasing numbers of comorbidities in each fracture type, but only proximal fractures were associated with an independent increase in mortality risk over and above comorbidity status.
In the 2 years following fracture, compared with matched controls, proximal fractures were associated with a greater risk of major hospital admission for conditions like cardiovascular disease, cancer, stroke, diabetes, pneumonia, and pulmonary disease. There was no significant difference between controls and those with distal fractures in hospital admission rate. The 2-year mortality risk was higher among subjects with proximal fractures, compared with patients in the no-fracture control group, regardless of whether they were admitted to the hospital, but there was no significant difference in those with distal fractures.
The differing clinical trajectories between those with proximal and distal fractures is a key finding, according to Dr. Center. The cause still isn’t clear, but she suspects that, in those patients who do badly, the fractures are either a signal that something is happening with existing comorbidities of the underlying frailty or that it may exacerbate them. Comorbidity independently and additively contributes to mortality, so that someone with a hip fracture and no comorbidities might have a similar mortality risk as someone with an upper-arm fracture and a couple of comorbidities. “I think it tells us that the person has to be treated as a whole. We need to treat the fracture to treat the underlying osteoporosis, but we also need to look closely at the person with the fracture and treat their comorbidities as well, because they seem to be more vulnerable,” Dr. Center said.
Although patients and clinicians are attuned to the concerns over hip fractures, other fractures should also be noted, according to Nelson Watts, MD, who is director of osteoporosis and bone-health services at Mercy Health in Cincinnati and was not involved in the research. “I think the message for clinicians and patients is that all of these [proximal] fractures need to be taken seriously. The good news is that that we have medications that can cut the risk of further fractures by 50%-70%,” he said in an interview.
Dr. Center has been on an advisory board for Amgen. Dr. Watts has been a speaker for Amgen and Radius and has conducted numerous clinical trials of osteoporosis drugs.
In addition to a series of news conferences, the Endocrine Society is also planning to host ENDO Online 2020 during June 8-22, which will feature on-demand and live programming for clinicians and researchers.
SOURCE: Center J et al. ENDO 2020, Abstract OR13-03.
Correction, 4/21/20: An earlier version of this article misstated when the interview with Dr. Center took place.