Information for participants of the RRID study

We are grateful to the many people who volunteered to participate in this study. Your contribution has been very valuable in helping us learn more about chronic kidney disease (CKD) so that each person with CKD can be offered the best treatment for them as an individual.

As summarised below, this means that most people with CKD do no need further tests or referral to a Kidney Consultant. We have already learned a great deal and our results have been published in several journals.

View the articles from data collected from the RRID study >

The most important finding so far are:

  1. The majority of people with CKD cared for by family doctors have only mildly reduced kidney function which is unlikely to cause any symptoms.
  2. Only a small proportion of people (6%) with CKD that is diagnosed by their family doctors require referral to a kidney consultant for further tests. The majority can be effectively cared for by their family doctor and simply require an annual check of their kidney function.
  3. CKD is often associated with other medical conditions and this should be taken into account when deciding on the best treatment.
  4. High blood pressure is commonly associated with CKD and it is important to treat this adequately.
  5. High salt intake is associated with factors that suggest a poorer outcome in people with CKD.
  6. Reducing salt intake is associated with better control of blood pressure in people with CKD.
  7. Vitamin D deficiency is present in a small proportion of people with CKD (6%) and there may be some benefit in checking for this because it is easy to treat.
  8. Skin autofluorescence and arterial  stiffness measurements may be useful and simple ways to identify people with CKD who are at higher risk for worsening of their kidney and/or heart disease  but more research is required to confirm this.
  9. The majority of people with CKD in our study had stable kidney function over 5 years (34%) and in a small but significant proportion (19%) the kidney function improved over time such that they no longer fulfilled the criteria for a diagnosis on “CKD”. Only a very small minority (0.2%) required dialysis by the end of 5 years.

We are currently following up people who participated in this study at 10 years after the first study visit. This involves data collection only using the hospital computer system and no further individual study visits are planned. The RRID study has joined the International Network of CKD Cohort Studies (iNET-CKD) which is sponsored by the International Society of Nephrology and aims to improve knowledge and understanding of CKD worldwide.