Management of advanced chronic kidney disease in primary care - current data from Germany

Applying data mining techniques to determine important parameters in chronic kidney disease and the relations of these parameters to each other

Introduction: Chronic kidney disease (CKD) includes a wide range of pathophysiological processes which will be observed along with abnormal function of kidneys and progressive decrease in glomerular filtration rate (GFR). According to the definition decreasing GFR must have been present for at least three months. CKD will eventually result in end-stage kidney disease. In this process different factors play role and finding the relations between effective parameters in this regard can help to prevent or slow progression of this disease. There are always a lot of data being collected from the patients’ medical records. This huge array of data can be considered a valuable source for analyzing, exploring and discovering information.

Objectives: Using the data mining techniques, the present study tries to specify the effective parameters and also aims to determine their relations with each other in Iranian patients with CKD.

Material and Methods: The study population includes 31996 patients with CKD. First, all of the data is registered in the database. Then data mining tools were used to find the hidden rules and relationships between parameters in collected data.

Results: After data cleaning based on CRISP-DM (Cross Industry Standard Process for Data Mining) methodology and running mining algorithms on the data in the database the relationships between the effective parameters was specified.

Conclusion: This study was done using the data mining method pertaining to the effective factors on patients with CKD.

Early referral to specialist nephrology services for preventing the progression to end-stage kidney disease

BACKGROUND

Early referral of patients with chronic kidney disease (CKD) is believed to help with interventions to address risk factors to slow down the rate of progression of kidney failure to end-stage kidney disease (ESKD) and the need for dialysis, hospitalisation and mortality.

OBJECTIVES

We sought to evaluate the benefits (reduced hospitalisation and mortality; increased quality of life) and harms (increased hospitalisations and mortality, decreased quality of life) of early versus late referral to specialist nephrology services in CKD patients who are progressing to ESKD and RRT. In this review, referral is defined as the time period between first nephrology evaluation and initiation of dialysis; early referral is more than one to six months, whereas late referral is less than one to six months prior to starting dialysis. All-cause mortality and hospitalisation and quality of life were measured by the visual analogue scale and SF-36. SF-36 and KDQoL are validated measurement instruments for kidney diseases.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2012; Issue 1) which contains the Cochrane Renal Group's Specialised Register; MEDLINE (1966 to February 2012), EMBASE (1980 to February 2012). Search terms were approved by the Trial Search Co-ordinator.

SELECTION CRITERIA

Randomised controlled trials (RCTs), quasi-RCTs, prospective and retrospective longitudinal cohort studies were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study quality and extracted data. Events relating to adverse effects were collected from the studies.

MAIN RESULTS

No RCTs or quasi-RCTs were identified. There were 40 longitudinal cohort studies providing data on 63,887 participants; 43,209 (68%) who were referred early and 20,678 (32%) referred late.Comparative mortality was higher in patients referred to specialist services late versus those referred early. Risk ratios (RR) for mortality reductions in patients referred early were evident at three months (RR 0.61, 95% CI 0.55 to 0.67; I² = 84%) and remained at five years (RR 0.66, 95% CI 0.60 to 0.71; I² = 87%). Initial hospitalisation was 9.12 days shorter with early referral (95% CI -10.92 to -7.32 days; I² = 82%) compared to late referral. Pooled analysis showed patients referred early were more likely than late referrals to initiate RRT with peritoneal dialysis (RR 1.74, 95% CI 1.64 to 1.84; I² = 92%).Patients referred early were less likely to receive temporary vascular access (RR 0.47, 95% CL 0.45 to 0.50; I² = 97%) than those referred late. Patients referred early were more likely to receive permanent vascular access (RR 3.22, 95% CI 2.92 to 3.55; I² = 97%). Systolic blood pressure (BP) was significantly lower in early versus late referrals (MD -3.09 mm Hg, 95% CI -5.23 to -0.95; I² = 85%); diastolic BP was significantly lower in early versus late referrals (MD -1.64 mm Hg, 95% CI -2.77 to -0.51; I² = 82%). EPO use was significantly higher in those referred early (RR 2.92, 95% CI 2.42 to 3.52; I² = 0%). eGFR was higher in early referrals (MD 0.42 mL/min/1.73 m², 95% CI 0.28 to 0.56; I² = 95%). Diabetes prevalence was similar in patients referred early and late (RR 1.05, 95% CI 0.96 to 1.15; I² = 87%) as was ischaemic heart disease (RR 1.05, 95% CI 0.97 to 1.13; I² = 74%), peripheral vascular disease (RR 0.99, 95% CI 0.84 to 1.17; I² = 90%), and congestive heart failure (RR 1.00, 95% CI 0.86 to 1.15; I² = 92%). Inability to walk was less prevalent in early referrals (RR 0.66, 95% CI 0.51 to 0.86). Prevalence of chronic obstructive pulmonary disease was similar in those referred early and late (RR 0.89, 95% CI 0.70 to 1.14; I² = 94%) as was cerebrovascular disease (RR 0.90, 95% CI 0.74 to 1.11; I² = 83%).The quality of the included studies was assessed as being low to moderate based on the Newcastle-Ottawa Scale. Slight differences in the definition of early versus late referral infer some risk of bias. Generally, heterogeneity in most of the analyses was high.

AUTHORS' CONCLUSIONS

Our analysis showed reduced mortality and mortality and hospitalisation, better uptake of peritoneal dialysis and earlier placement of arteriovenous fistulae for patients with chronic kidney disease who were referred early to a nephrologist. Differences in mortality and hospitalisation data between the two groups were not explained by differences in prevalence of comorbid disease or serum phosphate. However, early referral was associated with better preparation and placement of dialysis access.

Audit-based education lowers systolic blood pressure in chronic kidney disease: the Quality Improvement in CKD (QICKD) trial results

Strict control of systolic blood pressure is known to slow progression of chronic kidney disease (CKD). Here we compared audit-based education (ABE) to guidelines and prompts or usual practice in lowering systolic blood pressure in people with CKD. This 2-year cluster randomized trial included 93 volunteer general practices randomized into three arms with 30 ABE practices, 32 with guidelines and prompts, and 31 usual practices. An intervention effect on the primary outcome, systolic blood pressure, was calculated using a multilevel model to predict changes after the intervention. The prevalence of CKD was 7.29% (41,183 of 565,016 patients) with all cardiovascular comorbidities more common in those with CKD. Our models showed that the systolic blood pressure was significantly lowered by 2.41 mm Hg (CI 0.59-4.29 mm Hg), in the ABE practices with an odds ratio of achieving at least a 5 mm Hg reduction in systolic blood pressure of 1.24 (CI 1.05-1.45). Practices exposed to guidelines and prompts produced no significant change compared to usual practice. Male gender, ABE, ischemic heart disease, and congestive heart failure were independently associated with a greater lowering of systolic blood pressure but the converse applied to hypertension and age over 75 years. There were no reports of harm. Thus, individuals receiving ABE are more likely to achieve a lower blood pressure than those receiving only usual practice. The findings should be interpreted with caution due to the wide confidence intervals.

Identification and management of chronic kidney disease complications by internal medicine residents: a national survey

Many patients with chronic kidney disease (CKD) receive care from primary care physicians. Identification and management of CKD complications in primary care is suboptimal. It is not known if current residency curriculum adequately prepares a future internist in this aspect of CKD care. We performed an online questionnaire survey of internal medicine residents in the United States to determine knowledge of CKD complications and their management. Four hundred seventy-nine residents completed the survey with postgraduate year (PGY) distribution 166 PGY1, 187 PGY2, and 126 PGY3. Most of the residents correctly recognized anemia (91%) and bone disease (82%) as complications at estimated glomerular filtration rate less than 60 mL/min/1.73 m; however, only half of the residents identified coronary artery disease (54%) as a CKD complication. For a patient with estimated glomerular filtration rate less than 60 mL/min/1.73 m, two thirds of the residents would workup for anemia (62%), whereas half of them would check for mineral and bone disorder (56%). With regard to anemia of CKD, less than half of the residents knew the CKD goal hemoglobin level of 11 to 12 g/dL (44%); most would supplement iron stores (86%), whereas fewer would consider nephrology referral (28%). For mineral and bone disorders, many residents would recommend dietary phosphorus restriction (68%) and check 25-hydroxyvitamin D (62%); fewer residents would start 1,25-dihydroxyvitamin D (40%) or refer to the nephrologist (45%). Residents chose to discontinue angiotensin-converting enzyme inhibitor for medication-related complication of greater than 50% decline in estimated glomerular filtration rate (68%) and potassium greater than 5.5 mEq/L (93%). Mean performance score improved with increasing PGY (PGY1 59.4% ± 17.6%, PGY2 63.6% ± 15.6%, and PGY3 66.2% ± 16.5%; P = 0.002). Our study identified specific gaps in knowledge of CKD complications and management among internal medicine residents. Educational efforts such as instruction on use of CKD clinical practice guidelines may help raise awareness of CKD complications, benefits of early intervention, and improve CKD management.

Cardiovascular risk management in chronic kidney disease in general practice (the AusHEART study)

BACKGROUND

Chronic kidney disease (CKD) is common and increasing in prevalence. Adverse outcomes of CKD can be prevented through early detection and treatment. There is limited data on the awareness of CKD and the quality of care offered to patients with CKD in the primary care setting. The objectives of this study were to assess the prevalence, general practitioner (GP) awareness and extent of current evidence-practice gaps in the management of CKD in Australian primary care.

METHODS

The Australian Hypertension and Absolute Risk Study (AusHEART) was a nationally representative, cluster stratified, cross-sectional survey among 322 GPs. Each GP was asked to provide data for 15-20 consecutive patients (age ≥ 55 years) who presented between April and June, 2008. The main outcome measures were CKD prevalence based on proteinuria and decreased estimated glomerular filtration rate. Evidence-practice gaps in management of patients with CKD were identified.

RESULTS

Among a total of 4966 patients with kidney function test data, 1845 (37%) had abnormal kidney function. Of the 1312 patients with abnormal kidney function known to the GP at the time of visit, only 235 were correctly identified as having CKD. GPs under-estimated cardiovascular (CV) risks in patients with CKD when compared with the prevailing guidelines at the time of survey and the recent national guidelines, particularly in later stages of CKD. Among CKD patients not prescribed blood pressure-lowering agents or lipid-lowering agents, treatment was indicated as per relevant guidelines in 51 and 46%, respectively. For CKD patients who were already prescribed blood pressure-lowering and lipid-lowering agents, 61 and 50%, respectively, did not meet the treatment targets recommended by the relevant guidelines.

CONCLUSIONS

CKD is common, significantly under-recognized and under-treated in primary care. Effort to increase awareness and provide opportunities for improved screening and assessment should improve the management and outcome of these patients at high risk of CV disease.

How does late nephrological co-management impact chronic kidney disease? - an observational study

AIMS

To assess the impact of late referral (LR) for nephrological co-management compared with early referral (ER) on morbidity and mortality in chronic kidney disease (CKD) and to identify individual factors associated with higher mortality in LR, correcting for lead-time and immortal time bias.

PATIENTS AND METHODS

Retrospective observational study comparing 46 LR patients with 103 ER patients. The quality of CKD management was assessed by measures to prevent CKD progression and to modify CKD complications and cardiovascular risk factors according to current guidelines. One-year mortality of LR and ER was compared and factors associated with mortality were identified. Analysis was performed with equivalent GFR (glomerular filtration rate) of ER and LR at baseline to correct for lead-time and immortal time bias.

RESULTS

Late referral was associated with inferior control of most risk factors for CKD progression, CKD complications and cardiovascular risk factors. In particular, glycaemic control, the use of angiotensin converting enzyme inhibitors and angiotensin-2-receptor blockers in diabetic nephropathy or proteinuria, the control of nutritional and volume status were inferior in LR. One-year mortality was significantly higher in LR (RR 5.9 (95% CI 1.5-19.6); p < 0.01). Inadequate control of blood pressure, anaemia, volume status, malnutrition and emergency initial dialysis, but not LR itself were independently associated with mortality.

CONCLUSIONS

Late referral was associated with a substantially lower survival after correction for lead-time and immortal time bias and with inferior control of most risk factors for CKD progression, complications and cardiovascular risk factors. CKD patients may particularly profit from adequate control of blood pressure, anaemia, nutritional and volume status, and avoidance of emergency initial dialysis as these factors may predominately contribute to survival.