Deprivation influences the functional outcome from total hip arthroplasty

Socioeconomic inequality through deprivation and access to healthcare is an aetiological factor in many disease processes. It is associated with the development of osteoarthritis, the need for joint arthroplasty and poorer access to secondary healthcare. Few studies have investigated the influence of deprivation on the function of patients undergoing total hip arthroplasty. The aim of this study was to investigate the association between deprivation and function in these patients before their operation and at 18 months. The secondary aim was to investigate if deprivation was associated with comorbidity or adverse outcomes. A prospectively database of functional scores of 1865 patients undergoing total hip arthroplasty over seven years was used. Deprivation was categorized using the Scottish Index of Multiple Deprivation (SIMD) government rating. The most deprived quintiles had lower absolute functional scores at time of operation. At 18 months the least deprived quintile had a greater SF36 physical function score and relative improvement. Deprivation was not linked with length of stay or BMI. There was a higher proportion of ASA (American Society of Anesthesiologists) category 1 patients in the least deprived group signifying less comorbidity. Smoking was more prevalent in patients from areas of greater deprivation. There was no observed difference in mortality, infection, dislocation or thromboembolism. This study demonstrates a socioeconomic gradient in the function of patients undergoing total hip arthroplasty. Further investigation is required to elucidate the biological and social mechanisms driving these outcomes, and to determine whether these gradients persist at longer term follow-up.

II (Prognostic Studies--Investigating the effect of a patient characteristic on the outcome of disease).