Chronic kidney disease in patients with heart failure in German primary care practices: the InspeCKD study
Authors: Frese T , Wanner C , Schaeffner E , Opfermann U , Weber C , Radowsky F , Burckhardt F , Scherg F , Stahl P , Mader F 
Published: October 2024

Abstract

Background
Chronic kidney disease (CKD) is, alongside type 2 diabetes mellitus, the most common comorbidity in patients with heart failure (HF), with a prevalence of 40-50%. HF patients should therefore be screened, monitored, and treated according to international Kidney Disease Improving Global Outcomes (KDIGO) conclusions for early identification and intervention of CKD, with annual determination of eGFR to monitor kidney function and annual urine albumin-to-creatinine ratio (UACR) testing as appropriate. Early diagnosis is important as therapeutic options can be offered to slow the progression of CKD and reduce the risk of cardiovascular complications and mortality.

Purpose
Currently, there are only limited data available regarding screening, diagnosis and treatment of CKD for HF patients in German primary care physician (PCP) practices. Therefore, this analysis of the InspeCKD study was designed to examine the frequency of use of CKD-specific laboratory diagnostics in HF patients in routine PCP care.

Methods
In the current data analysis, fully anonymized patient data from German PCP practices were evaluated. In accordance with the screening recommendation of the KDIGO guideline, adult patients with diabetes, hypertension and/or cardiovascular disease, including HF, with at least one year of observation period were included in the analysis.

Results
The overall patient cohort comprised 448.837 patients from 1.244 German PCP practices. Of the 7.9% HF patients, 6.1% participated in a disease management program (DMP) for coronary heart disease. The average age of HF patients was 74 years.
The prevalence of diagnosed CKD in HF patients during the observational period (mean: 1.7 years) was 26.8%. Within the subgroup of patients with HF, serum creatinine to estimate GFR was measured at least once in 48.5% of patients. Urine dipstick testing for albuminuria was performed in 7.4% of patients and UACR was measured at least once in 0.3% of patients. In patients with at least one documented measurement, eGFR and UACR were checked 2.2 and 0.9 times, respectively, per patient and year. Of the HF patients with laboratory-confirmed CKD according to KDIGO criteria, 81.8% were not diagnosed with CKD.

Conclusion
The analysis shows that, given the high prevalence of CKD in HF patients and the current KDIGO recommendations for early identification and intervention of CKD, a substantial proportion of HF patients in German PCP practices did not receive adequate laboratory diagnostics for early diagnosis of CKD. In addition, the majority of patients with laboratory-confirmed CKD were not diagnosed. Early detection of CKD and the use of evidence-based therapeutic options can significantly reduce the risk of CKD progression. In conclusion, there is an urgent need to raise awareness among PCPs about secondary and tertiary prevention of CKD in patients with HF and to include coordinated CKD screening recommendations in HF guidelines.