DOS 2016

182

· DOS Abstracts

Eighteen-year trends in comorbidity and

subsequent mortality in total hip or knee

arthroplasty patients: A Danish nationwide,

population-based cohort study, 1996-2013

Eva Natalia Glassou, Alma Becic Pedersen, Torben Bæk Hansen

University clinic of hand, hip and knee surgery, Department of Orthopedic

Surgery, Regional Hospital West Jutland; Department of Clinical Epidemiology,

Aarhus University Hospital; University clinic of hand, hip and knee surgery,

Department of Orthopedic Surgery, Regional Hospital West Jutland

Background:

The incidence of total hip and knee arthroplasty (THA and TKA)

has increased over the last decades. This increase may be explained by the ag-

ing of the population and an improved safety of the procedures, which has ex-

panded the indications for surgery. Patients with several comorbid conditions

are now considered suitable candidates for THA and TKA.

Purpose / Aim of Study:

We examined changes in comorbidity over time and

their impact on mortality following primary THA and TKA in patients with OA.

Materials and Methods:

We used the Danish Arthroplasty Registers to iden-

tify THA and TKA patients from 1996 to 2013. From administrative databases

we collected data on comorbidities, which were used to calculate the Charlson

Comorbidity Index. Patients were divided into four comorbidity groups (none,

low, moderate, high). We calculated the relative risk (RR) of mortality within

90 days post-surgery with a 95% confidence interval (CI) stratified by year of

surgery.

Findings / Results:

In total, 99,886 THAs and 63,718 TKAs were included.

The proportion of THA patients with low, moderate and high comorbidity bur-

den increased 3-4% during the period of interest. Compared to patients with no

comorbidity, THA patients with low, moderate and high comorbidity burden had

an RR of 90-day mortality of 1.9 (CI: 1.6-2.4), 1.9 (CI: 1.4-2.5), and 3.3 (CI:

2.6-4.2), respectively. Similar increases in proportions and RRs were observed

in TKA patients with moderate and high comorbidity burden.

Conclusions:

The number of THA and TKA procedures performed on patients

with comorbidities increased over the past 18 years. The mortality risk was

dependent of the comorbidity burden. Patients with moderate or severe co-

morbidity burden had an increased risk of dying within 90 days post-surgery

regardless of year of surgery.

No conflicts of interest reported

133.