The Prevalence of CKD in Australian Primary Care: Analysis of a National General Practice Dataset

Abstract

Introduction: The prevalence of chronic kidney disease (CKD) in Australia varies substantially across reports. Using a large, nationally representative general practice data source, we determined the contemporary prevalence and staging of CKD in the Australian primary care.

Methods: We performed a retrospective, community-based observational study of 2,720,529 adults with ≥1 visit to a general practice participating in the MedicineInsight program and ≥1 serum creatinine measurement (with or without a urine albumin-to-creatinine ratio [UACR] measurement) between 2011 and 2020. CKD prevalence was estimated using 3 definitions based on estimated glomerular filtration rate (eGFR) and UACR measurements with varying degrees of rigidity in terms of the number of measurements assessed to define CKD ("least", "moderate" and "most" rigid).

Results: CKD prevalence in the cohort progressively increased over the 10-year study period, irrespective of the method used to define CKD. In 2020, CKD prevalence in the cohort was 8.4%, 4.7%, and 3.1% using the least, moderate, and most rigid definition, respectively. The number of patients with UACR measurements was low such that, among those with CKD in 2020, only 3.8%, 3.2%, and 1.5%, respectively, had both eGFR and UACR measurements available in the corresponding year. Patients in whom both eGFR and UACR measurements were available mostly had moderate or high risk of CKD progression (83.6%, 80.6%, and 76.2%, respectively).

Conclusion: In this large, nationally representative study, we observed an increasing trend in CKD prevalence in primary care settings in Australia. Most patients with CKD were at moderate to high risk of CKD progression. These findings highlight the need for early detection and effective management to slow progression of CKD.

Keywords: UACR; chronic kidney disease; eGFR; epidemiology; prevalence; primary care.

Graphical abstract

Figure 1

Identification of the study cohort. eGFR, estimated glomerular filtration rate; UACR, urine albumin-to-creatinine ratio.

Figure 2

Annual prevalence of chronic kidney disease in MedicineInsight (2011–2020). CKD was defined as follows: (i) an estimated glomerular filtration rate (eGFR) <60 ml/min per 1.73 m² (with or without albuminuria) or an eGFR ≥60 ml/min per 1.73 m² with an ACR ≥2.5 mg/mmol for males and ≥3.5 mg/mmol for females, (ii) 2 consecutive eGFR measures <60 ml/min per 1.73 m² at least 90 days apart (with or without albuminuria) or an eGFR ≥60 ml/min per 1.73 m² with an urine albumin-to-creatinine ratio ≥2.5 mg/mmol for males and ≥3.5 mg/mmol for females, and (iii) 2 consecutive eGFR measures <60 ml/min per /1.73m at least 90 days part and/or 2 consecutive urine albumin-to-creatinine ratio measures ≥2.5 mg/mmol for males and ≥3.5 mg/mmol for females at least 90 days apart; “N” (“denominator”) represents the number of patients eligible for ascertainment of CKD status (patients with ≥1 general practice visit or a laboratory test result in the calendar year) in each calendar year. CKD, chronic kidney disease; eGFR, estimated glomerular filtration rate.

Figure 3

Chronic kidney disease prevalence in 2020 in MedicineInsight by KDIGO stage. ∗Presented as a proportion of patients with CKD in whom both eGFR and UACR measurements were available in 2020 to allow staging of CKD according to both markers (3.8% [n = 56,618], 3.2% [n = 46,626] and 1.5% [n = 22,876] across definition 1, 2, and 3, respectively); in 2020, there were 1,469,833 patients eligible for ascertainment of CKD status; Colors denote risk of CKD progression as per the KHA-CARI diagnosis, classification, and staging of CKD guidelines as follows: yellow = moderate risk; orange = high risk; red = very high risk; number in parentheses indicates absolute number of patients. CKD, chronic kidney disease; eGFR, estimated glomerular filtration rate KHA-CARI, Kidney Health Australia–Caring for Australian and New Zealanders with Kidney Impairment; UACR, urine albumin-to-creatinine ratio.