A KANG1, L SUKKAR1, M JUN1, C FOOTE1,2, R PECOITS-FILHO1,3, B NEUEN1, A SCARIA1, J BAKER1, K ROGERS1, A CASS4, C POLLOCK5, D SULLIVAN6, G WONG7, J KNIGHT1, D PEIRIS1, M GALLAGHER1, M JARDINE1
1The George Institute for Global Health, University Of New South Wales, Sydney, Newtown, Australia, 2Concord Repatriation General Hospital , Concord, Australia, 3Pontificia Universidade Catolica do Parana, Curitiba, Brazil, 4Menzies School of Health Research, Darwin, Australia, 5Kolling Institute for Medical Research, St Leonards, Australia, 6NHMRC Clinical Trials Centre, University of Sydney, Camperdown, Australia, 7Centre for Kidney Research, University of Sydney, Westmead, Australia
Aim: To assess: 1) the incidence and prevalence of chronic kidney disease (CKD), 2) risk factors for incident CKD in a contemporary New South Wales population-based cohort of adults aged 45 and older.
Background: The AUSDIAB study found an incidence rate of CKD (eGFR<60ml/min/1.73m2) of 0.4 per 100 person-years in the adult Australian community aged ≥25 years.
Methods: Based on data from the EXTEND45 study (the 45 and Up Study linked to hospital and community pathology datasets by the Centre for Health Record Linkage[CHeReL] and the Medicare Benefits Schedule[MBS] and Pharmaceutical Benefits Scheme[PBS] datasets provided by the Department of Human Services), we identified a population-based cohort (2006-2014) of 41,099 people aged ≥45 years who had ≥2 measures of kidney function. Prevalent CKD (defined as eGFR <60 ml/min/1.73m2) was determined at study recruitment. The CKD incidence rate over the study period was determined using Poisson regression. Cox regression was used to determine associations between baseline sociodemographic factors, comorbidities and future incident CKD.
Results: Of 41,099 participants, 7,641(18.6%) had prevalent CKD and 5,481 developed incident CKD over a mean follow-up of 5.6 years. The incidence rate of CKD was 3.2(95% CI:3.1-3.3) per 100 person-years. Baseline characteristics: age (per year increase; HR: 1.08[1.07-1.08]), regional residence (inner regional vs city: 1.26[1.18-1.36]), diabetes (1.28[1.19-1.38]), hypertension (1.58[1.48-1.70]), heart disease (1.22[1.14-1.31]), stroke (1.16[1.03-1.29]), depression (1.25[1.15-1.35]) and higher BMI (obese vs normal: 1.38[1.27-1.49]) were predictive of incident CKD. Alcohol consumption (7-13 vs 0-6 drinks/week 0.89[0.82-0.97]) was associated with a lower risk of incident CKD.
Conclusions: Baseline depression and regional residence predicted future incident CKD in conjunction with established risk factors of age, diabetes, hypertension, high BMI and vascular disease.
Amy Kang is nephrologist and PhD student at the George Institute for Global Health, UNSW, Sydney.