Social deprivation indices of patients on renal replacement therapy (RRT) in Grampian

Do rates of hospital admission for falls and hip fracture in elderly people vary by socio-economic status?

OBJECTIVE

To determine the relationship between hospital admissions for falls and hip fracture in elderly people and area characteristics such as socio-economic deprivation.

STUDY DESIGN

Ecological study of routinely collected hospital admissions data for falls and hip fracture in people aged 75 years or over for 1992-1997, linked at electoral ward level with characteristics from census data.

METHODS

In total, 42,293 and 17,390 admissions were identified for falls and hip fracture, respectively, from 858 electoral wards in Trent. Rate ratios (RRs) for hospital admissions for falls and hip fracture were calculated by the electoral wards' Townsend score divided by quintiles. RRs were estimated by negative binomial regression and adjusted for the ward characteristics of age, gender, ethnicity, rurality, proportion of elderly people living alone and distance from hospital.

RESULTS

There was a small but statistically significant association at electoral ward level between hospital admissions for falls and the Townsend score, with the most deprived wards having a 10% higher admission rate for falls compared with the most affluent wards (adjusted RR 1.10, 95% CI 1.01-1.19). No association was found between hospital admission for hip fracture and deprivation (adjusted RR 1.05, 95% CI 0.95-1.16).

CONCLUSION

There is some evidence of an association at electoral ward level between hospital admissions for falls and socio-economic deprivation, with higher rates in deprived areas. No such association was found for hip fracture. Further work is required to assess the impact of interventions on reducing inequalities in hospital admission rates for falls in elderly people.

Exploring the pathways leading from disadvantage to end-stage renal disease for Indigenous Australians

Indigenous Australians are disadvantaged, relative to other Australians, over a range of socio-economic and health measures. The age- and sex-adjusted incidence of end-stage renal disease (ESRD)--the irreversible preterminal phase of chronic renal failure--is almost nine times higher amongst Indigenous than it is amongst non-indigenous Australians. A striking gradient exists from urban to remote regions, where the standardised ESRD incidence is from 20 to more than 30 times the national incidence. We discuss the profound impact of renal disease on Indigenous Australians and their communities. We explore the linkages between disadvantage, often accompanied by geographic isolation, and both the initiation of renal disease, and its progression to ESRD. Purported explanations for the excess burden of renal disease in indigenous populations can be categorised as: primary renal disease explanations;genetic explanations;early development explanations; and socio-economic explanations. We discuss the strengths and weaknesses of these explanations and suggest a new hypothesis which integrates the existing evidence. We use this hypothesis to illuminate the pathways between disadvantage and the human biological processes which culminate in ESRD, and to propose prevention strategies across the life-course of Indigenous Australians to reduce their ESRD risk. Our hypothesis is likely to be relevant to an understanding of patterns of renal disease in other high-risk populations, particularly indigenous people in the developed world and people in developing countries. Furthermore, analogous pathways might be relevant to other chronic diseases, such as diabetes and cardiovascular disease. If we are able to confirm the various pathways from disadvantage to human biology, we will be better placed to advocate evidence-based interventions, both within and beyond the scope of the health-care system, to address the excess burden of renal and other chronic diseases among affected populations.

What determines geographical variation in rates of acceptance onto renal replacement therapy in England?

OBJECTIVE

To determine the independent effects of need and supply factors on the known geographical variation in acceptance rates onto renal replacement therapy (RRT) in England.

METHODS

Data were obtained from all renal units in England on the characteristics of all cases aged 16 years and over, resident in England, who were accepted onto RRT in 1991 and 1992. Of these, 5715 (94.5%) had a valid postcode that could be matched to a census ward. Multilevel modelling using Poisson regression was used. The number of acceptances in each census ward within age bands 16-34, 35-64 and 65+ was the dependent variable. Independent effects modelled were: (1) individual factors (age, sex); (2) census ward need factors--ethnicity (expressed as the percentage of the ward population that was Asian or African-Caribbean), socio-economic deprivation--and supply factors--'access' to the nearest renal unit using crowfly and road travel time and distance, and services available to each ward expressed as number of haemodialysis stations per 100,000 catchment population of the nearest renal unit; (3) district health authority level effects.

RESULTS

Age was a major determinant of acceptance, with a 7-fold higher rate in males aged over 64 years compared with younger men. Acceptance rates were lower in females, with a negative age-sex interaction in females aged over 64 years. The percentage of both Asian and African-Caribbean populations per ward was a highly significant positive determinant. Deprivation was also a significant determinant, best represented by a customised index. There was an inverse relation of acceptance with distance, especially road travel time. Other supply side variables had a significant effect though there was no independent district effect. There was some variation in the strength of these relationships by type of area (Greater London, urban and non-urban).

CONCLUSIONS

Need and supply factors influence service use as expressed as acceptance onto RRT. Pressure to expand RRT services needs to be aimed at areas with large minority ethnic populations and those living far from existing units.