In 2013, the Kidney Disease: Improving Global Outcomes (KDIGO) foundation published its clinical practice guideline for lipid management in chronic kidney disease (CKD).1 This guideline modified the previous recommendations, widening the indications for statin therapy to improve the prevention of cardiovascular (CV) disease in patients with CKD. Statin therapy was recommended to all patients over 50 years of age with CKD and to certain subgroups of patients between 18 and 49 years of age with CKD (Table 1). Lipid profile assessment was also recommended in all adults with newly identified CKD, but without specifying new follow-up measures in most patients.

In 2014, the panel of members of the Eighth Joint National Committee (JNC 8) published the evidence-based guideline for the management of high blood pressure (HTN) in adults.2 This guideline differed notably on the point of HTN management compared to the previous report by the Seventh Joint National Committee (JNC 7).3 The new guideline changed the target blood pressure (BP), making them less stringent. In adult patients <60 years of age, with an estimated glomerular filtration rate (eGFR)<60ml/min and/or diabetes, the target BP was changed from <130/80mmHg to <140/90mmHg, and in patients >60 years, the target BP was changed from <140/90mmHg to 150/90mmHg.

In a nephrology outpatient clinic, we monitored incident and prevalent patients with CKD, in whom it is important to study the various CV risk factors and risk factors for CKD progression. Taking into account these recent updates on lipid and high blood pressure management, we designed this study to assess the suitability of the various clinical practice guidelines in a sample of patients from our outpatient practice, as well as the impact of the changes to guideline targets in our population.

The new guidelines for HTN treatment and lipid management in patients with CKD have a significant impact on the management of our patients in routine clinical practice.

Both dyslipidaemia and HTN are independent CV risk factors and are highly prevalent in patients being followed in nephrology clinics. Adequate control of these factors is a challenge in patients with CKD.

The JNC 8 guideline published in 2014 for the management of HTN is more flexible with BP targets, thereby improving BP control in our patients, especially older patients. In contrast, the KDIGO lipid management guideline published in 2013 has widened the indication of statin therapy in our patients, meaning that the treatment of patients with CKD being followed up in our clinic is now inadequate.

Firstly, the KDIGO foundation's clinical practice guideline for lipid management was published in 2013. This guideline widens the indication of dyslipidaemia treatment in patients with CKD based on coronary artery disease and age, and does not recommend the use of LDL-C as a guide to identify those patients who should be treated with statins, nor as a treatment target. This guideline has been extensively analysed by other groups such as the Kidney Disease Outcomes Quality Initiative (KDOQI), showing support the majority of the recommendations, but they highlight some areas as too strict or requiring clarification.6 In our sample, it is worth noting that 87.21% of patients met the requirements to start statin therapy according to the new KDIGO guideline, but only 58.10% of those who met the requirements actually received the medication. Attention has also been drawn to a very significant increase in the statin prescription rate required by the implementation of the KDIGO guideline by other groups such as Schneider et al., who studied a population of 5217 German adults with CKD and observed a need to increase prescription of statins from 47% to 88%7; this is in line with our data. In our population, a comparison of the subgroup of patients receiving statin therapy with those not receiving it but in whom it is indicated found that these were patients with more profuse history of CV disease, DM and HTN. They had lower rates of total cholesterol and HDL-C, associated with this treatment. In a study conducted in the United States of America with data from the NHANES registry, published in 2014, which studied the impact of the application of the guidelines for the treatment of cholesterol published in 2013 by the American College of Cardiology, observed similar findings. The application of this new guideline means an increase in the indication of statins of >50%, affecting over 12.8 million people and above all increasing the indication in older patients and those with increased CV risk.8

In the future, it will be necessary to assess the impact of the application of this guideline, which increases the indication of the prescription of statins, especially in the high-CV risk population, on the prevention of CV events and mortality.

In relation to BP, the majority of our patients (97.7%) were in the group of patients under 60 years of age with either an eGFR<60ml/min, ACR>30mg/g or a diagnosis of DM. Analysing the general differences between patients with controlled and uncontrolled BP according to the new JNC 8 guidelines, patients who achieve the target BP are younger, with better kidney function and less proteinuria. Although the percentage of patients with controlled BP in our sample according to the current guidelines has improved, it remains insufficient at only 47.85%, reflecting a need to increase BP control efforts in our population. Two other studies presented by our group also evaluated the suitability of the guidelines at that time: in 2003 we presented a study of 1004 patients, 24% of whom achieved BP values <130/85mmHg,9 and in 2007 we presented 600 patients, 35% of whom achieved BP levels <130/80mmHg.10

The new JNC 8 clinical practice guidelines for the management of HTN is more flexible with BP targets, with the result that in our sample of patients with an eGFR<60ml/min or ACR>30mg/g, with DM or <60 years of age, the percentage of patients with controlled BP has increased from 22.4% to 47.5% as compared with the targets indicated in the preceding JNC 7 guidelines. When drafting the JNC 8 guidelines, the investigators included randomised, controlled clinical trials that indicated that there was no benefit in tighter BP control (below 140/90mmHg) in this group of patients. However, the results of the studies on which those guidelines were based were disputed and did not have a high level of evidence. The most relevant of them, the ACCORD study conducted on more than 4000 patients, did not find a significant difference in the frequency of CV events in patients with tight BP control (SBP<120 vs. <140mmHg), but only diabetic patients were included.11 The SPS3 trial studied patients with a history of lacunar stroke, and although it did not observe a decrease in the rate of recurrence of infarction in patients with tight BP control (SBP<130mmHg), it did find a significant decrease in the rate of intracranial haemorrhage.12 The Cardio-Sis study did observe a lower incidence of left ventricular hypertrophy and compound CV events in the group with tighter BP control (SBP<130 vs 140mmHg).13 Finally, the Japanese JATOS study also failed to find significant differences in the end-points studied between BP control groups, but did warn of probable age-related interferences that may have obscured the results.14 In light of the above, the JNC 8 recommendations have been extensively re-evaluated by various societies and research groups, generating controversy around the new BP control targets,15,16 and it would at least seem to be widely accepted that these recommendations are no alternative for clinical judgement, and that decisions on medical care must be tailored to each patient.17,18 The recent publication of the results of the SPRINT study19 has further entrenched the debate around the BP control values proposed by the JNC 8. This randomised clinical trial included more than 8000 non-diabetic patients with increased CV risk, with a mean age of 67.9 years, who were randomised to two SBP control targets using the same values as the ACCORD study: strict control (<120mmHg) or standard control (<140mmHg), finding a significant reduction in the appearance of the primary end-point (combination of any CV event or CV mortality), as well as secondary end-points such as all-cause mortality among patients with strict SBP control, leading to the early termination of the study in spite of not having demonstrated effects on kidney disease progression. The meta-analysis of 123 studies conducted by Ettehad et al. and published recently in the Lancet corroborated these results, finding a reduction in CV risk with BP values below 130mmHg.20

When we analyse the reclassified patients in our study, who achieved the target BP according to the 2014 guidelines, but not according to the earlier guidelines, we observed that these patients were older, had a greater CV history and fewer had diabetes. We also observed that the improvement in the proportion of patients with controlled BP was due mainly to an increase in the number of controlled patients >60 years of age, from 17.2% to 58.1%, while in those under 60 the increase was much smaller, from 31.5% to 40%. An American study published in 2014 found similar data on the impact of the application of the JNC 8 guidelines, with an improvement of around 20% in the number of patients with controlled BP, but fundamentally an improvement in BP control in older patients.21 This group of subjects reclassified under the 2014 guidelines is similar to that studied in the SPRINT trial, which demonstrated a significant reduction in the risk of CV events, CV mortality and all-cause mortality, with tighter BP control in older, non-diabetic, high-CV risk patients with a mean age of 67.9 years.17

In any event, in view of the data from the SPRINT study, there is reason to doubt the benefits of relaxing BP targets in the at-risk population (older and with increased CV risk) on CV events and mortality. It would also seem reasonable to review the current clinical practice guidelines on BP control in patients with CKD.

Our study is not without limitations, as it is a single-centre observational study based on a single lab test and BP reading taken during a medical consultation, but it does highlight the important impact of the implementation of the new guidelines for HTN and dyslipidaemia treatment in our patients.

The amended lipid metabolism and HTN treatment recommendations has had a significant impact on the clinical management of our patients. In our population of patients with CKD, the new KDIGO guideline for dyslipidaemia treatment has meant an increase in the indication of statin therapy, especially in patients with increased CV risk. In contrast, the JNC 8 guidelines have increased the percentage of patients with controlled BP, especially in older patients and those with increased CV risk. Nevertheless, in view of the latest research, less stringent control of BP may lead to an increased risk of CV events and mortality in these patients and may require the BP recommendations to be updated, at least for patients with CKD.

The authors declare that they have no conflicts of interest.