The multidimensional nature of renal disease: rates and associations of albuminuria in an Australian Aboriginal community.

BACKGROUND: An epidemic of end-stage renal disease (ESRD) is accompanying the rising rates of hypertension, type 2 diabetes and cardiovascular disease among Aborigines in the Northern Territory of Australia. Incidence rates are now 21 times those of nonAboriginal Australians and are doubling every four years. We describe the rates and associations of renal disease in one remote community, which has a current ESRD incidence of 2700 per million, and cardiovascular mortality among the highest in Australia. METHODS: Between 1992 and 1995 a community-wide screening program was conducted, in which the urinary albumin/creatinine ratio (ACR) was used as the chief renal disease marker. More than 90% of the population ages five and older participated. RESULTS: Albuminuria was evident in early childhood and increased dramatically with age; 26% of adults had microalbuminuria and 24% had overt albuminuria. All renal failure developed out of a background of overt albuminuria. ACR was significantly correlated with the presence of scabies at screening, with a history of poststreptococcal glomerulonephritis, which is epidemic and endemic in the community, with increasing body wt, blood pressure, glucose, insulin and lipid levels, and with evidence of heavy drinking. ACR was also significantly and inversely correlated with birth weight. As a result of its association with deteriorating hemodynamic and metabolic profiles, increasing ACR was also correlated with increasing cardiovascular risk score. Direct observations showed, and multivariate models predicted, progressive amplification of ACR when multiple risk factors were present simultaneously. Albuminuria also clustered in families. CONCLUSION: Renal disease in this population is multifactorial, with risk factors related to whole-of-life nutrition, metabolic and hemodynamic profiles, infections, health behaviors, and possibly a family predisposition. Its relationship to low birth weight, and its associations with deteriorating metabolic and hemodynamic profiles, suggest that renal disease is, in part, a component of Syndrome X, which explains the simultaneous increase in metabolic, cardiovascular and renal disease in Aboriginal people. The family clustering might have both environmental and genetic causes, and is under further investigation. Most of the identified risk factors arise out of poverty, disadvantage and accelerated lifestyle change, and the current epidemic can be explained by the confluence of many risk factors in the last few decades. The introduction of effective and sustained programs to address social, economic and educational inequities in all Aboriginal communities, and of screening and renal- and cardiovascular-protective treatment programs for those already afflicted are matters of great urgency.

A health profile of adults in a Northern Territory aboriginal community, with an emphasis on preventable morbidities.

We conducted a brief health survey of adults in an isolated Northern Territory Aboriginal community, whose standardised mortality rates are the second highest in Australia. The screen revealed high rates of smoking and excessive drinking, of preventable infections and their sequelae, and of hypertension, insulin resistance, diabetes and renal disease. The infectious morbidities were more pronounced and the life-style morbidities almost entirely new since a health screen in 1957. Most morbidities were strongly associated with identifiable risk factors, such as overweight, smoking, excessive drinking, skin sores and scabies, all of which which are amenable to modification. Problems with food supply and pricing, poor food choices and diversion of money to cigarettes, beer and gambling all contributed to poor nutrition. Low birthweight probably compounds the risk for serious adult disease associated with these environmental influences. This profile highlights the failure of current systems to deal with health needs. Improvements in infrastructure, education and employment, and reinvigoration of preventive and primary health care programs, assumption of responsibility for health by the community and by individuals themselves, and better management of existing morbidities are essential to rectifying this shameful situation.