We know that fracture is quite common in the community. We also know that fracture increases the risk of death. Our latest work suggests that multimorbidity can explain why patients with a fracture have higher risk of death.
A few years ago my 70-year old neighbour broke his hip after falling from a staircase. As a physically active man, he was optimistic that he would get on his feet again soon. Unfortunately, 6 months after being discharged from the hospital, he died. I was surprised at his death.
I should mention that my neighbour had had type 2 diabetes and hypertension for more than 10 years, but the conditions had been well controlled.
Why do patients with a fracture have excess mortality risk? I think it is partly due to the presence of concomitant illnesses among fractured patients. My colleagues and I have tested this hypothesis, and our results have just been published in JAMA Network Open.
Our analysis was based on Danish National Hospital Discharge Register that included 308,870 individuals aged 45 years (95,372 men) and older who had had a fracture. During a median of 6.5 years of follow-up, 40% of men and 38.5% of women died after the fracture event.
In our study, 43% of patients with a fracture have multimorbidity, 1.4-fold higher than that in the general population. However, in the fractured patients, women have a lower prevalence than men (39% vs 51%). By exploiting the inter-correlation among comorbidities, we classified them into 4 major groups: low multimorbidity (65% of total), cardiovascular disorders (24%), diabetes (5%) and malignancy (5%).
Excess mortality risk
Then, we quantified the excess mortality by an index called ‘excess risk’ which is defined as the ratio of the risk of mortality among patients with a fracture over the risk of mortality in the background population. So, an excess risk of 1.2 means that the risk of death associated with a fracture is 20% higher than that in the general population of the same age and gender. We then analyzed the excess risk by multimorbidity group.
What did we find? Well, we found that fractured patients with multimorbidity have a greater risk of mortality. The excess risk varied…