Hugh Gallagher

Broadening Options for Long-term Dialysis in the Elderly (BOLDE): differences in quality of life on peritoneal dialysis compared to haemodialysis for older patients

Background. Health-related quality of life (QOL) is an important outcome for older people who are often on dialysis for life. Little is, however, known about differences in QOL on haemodialysis (HD) and peritoneal dialysis (PD) in older age groups. Randomising patients to either modality to assess outcomes is not feasible. Methods. In this cross-sectional, multi-centred study we conducted QOL assessments (Short Form-12 Mental and Physical Component Summary scales, Hospital Anxiety and Depression Scale and Illness Intrusiveness Ratings Scale) in 140 people (aged 65 years or older) on PD and HD. Results. The groups were similar in age, gender, time on dialysis, ethnicity, Index of Deprivation (based on postcode), dialysis adequacy, cognitive function (Mini-Mental State Exam and Trail-Making Test B), nutritional status (Subjective Global Assessment) and social networks. There was a higher comorbidity score in the HD group. Regression analyses were undertaken to ascertain which variables significantly influence each QOL assessment. All were influenced by symptom count highlighting that the patient’s perception of their symptoms is a critical determinant of their mental and physical well being. Modality was found to be an independent predictor of illness intrusion with greater intrusion felt in those on HD. Conclusions. Overall, in two closely matched demographic groups of older dialysis patients, QOL was similar, if not better, in those on PD. This study strongly supports offering PD to all suitable older people.

The Pan-Thames EPS study: treatment and outcomes of encapsulating peritoneal sclerosis

BACKGROUND Encapsulating peritoneal sclerosis (EPS) is a disease process that can occur as a complication of peritoneal dialysis (PD). The aim of this study was to make a general assessment of the clinical features, diagnosis, management and outcome of PD-related EPS cases from London and South-East England. METHODS Questionnaires were sent to 11 PD units in March 2007; cases were identified retrospectively. Outcome data on surviving patients were collected in March 2008. RESULTS A total of 111 patients were identified; the mean time on PD was 82 months (range 8-247). Mortality increased with length of time on PD, being 42% at <3 years (n = 12), 32% at 3-4 years (n = 19), 61% at 5-6 years (n = 31), 54% at 7-8 years (n = 24), 75% at 9-10 years (n = 8) and 59% at >10 years (n = 17). Twelve patients had no previous peritonitis episodes, 28 had one previous episode, 30 had two previous episodes and 33 had three or more previous episodes. Of the patients with PD details available, 41/63 were high (>0.81) transporters and 44/71 had ultrafiltration <1 l/24 h, but 7/63 were low average transporters (0.5-<0.65) and 27/71 had ultrafiltration >1 l/24 h and a few had significant residual renal function. Sixty-five (59%) patients had their PD discontinued prior to diagnosis (51 HD; 14 transplanted). CT scans were performed on 91 patients and laparotomy on 47 patients. Drug treatment consisted of tamoxifen, immunosuppression or both. The median survival was 15 months in patients treated with tamoxifen (n = 17), 12 months in patients treated with immunosuppression (n = 24) and 21 months in patients who received both (n = 13), against 13 months (n = 46) in patients who received no specific treatment. Adhesionolysis was performed in 5 patients, and 39 patients were given parenteral nutrition. The overall mortality was 53% with a median survival of 14 months and a median time to death of 7 months. Conclusion. This is one of the largest cohorts of patients with EPS in the literature. Long-term survival occurred in over 50%, regardless of the various treatments strategies undertaken by the centres.

Creatinine fluctuation has a greater effect than the formula to estimate glomerular filtration rate on the prevalence of chronic kidney disease.

Background/Aims: Cases of chronic kidney disease (CKD) are defined by the estimated glomerular filtration rate (eGFR), calculated using the Modified Diet in Renal Disease (MDRD) or, more recently, the CKD Epidemiology Collaboration (CKD-EPI) formula. This study set out to promote a systematic approach to reporting CKD prevalence. Design, Setting, Participants and Measurements: The study explores the impact of the way in which eGFR is calculated on the prevalence of CKD. We took into account whether including (1) ethnicity, (2) using a single eGFR, (3) using more than 1 eGFR value or (4) using the CKD-EPI formula affected the estimates of prevalence. Sample: Of 930,997 registered patients, 36% (332,891) have their eGFR defined (63% of those aged 50–74 years, 81% >75 years). Results: The prevalence of stage 3–5 CKD is 5.41% (n = 50,331). (1) Not including ethnicity data the prevalence would be 5.49%, (2) just using the latest eGFR 6.4%, (3) excluding intermediary values 5.55% and (4) using the CKD-EPI equation 4.8%. All changes in eGFR (t test) and the proportion with CKD (χ2 test) were significant (p < 0.001). Using serum-creatinine-calculated eGFR instead of laboratory data reduced the prevalence of stage 3–5 CKD by around 0.01%. Sixty-six percent of people with stage 3–5 disease have cardiovascular disease and 4.0% significant proteinuria using the MDRD formula; the corresponding figures using CKD-EPI are 74 and 4.6%. Conclusions: A standardised approach to reporting case finding would allow a better comparison of prevalence estimates. Using a single eGFR tends to inflate the reported prevalence of CKD by ignoring creatinine fluctuation; this effect is greater than the difference between MDRD and CKD-EPI.

A method of identifying and correcting miscoding, misclassification and misdiagnosis in diabetes: a pilot and validation study of routinely collected data

Diabet. Med. 27, 203–209 (2010)

The QICKD study protocol: a cluster randomised trial to compare quality improvement interventions to lower systolic BP in chronic kidney disease (CKD) in primary care

BackgroundChronic kidney disease (CKD) is a relatively newly recognised but common long-term condition affecting 5 to 10% of the population. Effective management of CKD, with emphasis on strict blood pressure (BP) control, reduces cardiovascular risk and slows the progression of CKD. There is currently an unprecedented rise in referral to specialist renal services, which are often located in tertiary centres, inconvenient for patients, and wasteful of resources. National and international CKD guidelines include quality targets for primary care. However, there have been no rigorous evaluations of strategies to implement these guidelines. This study aims to test whether quality improvement interventions improve primary care management of elevated BP in CKD, reduce cardiovascular risk, and slow renal disease progressionDesignCluster randomised controlled trial (CRT)MethodsThis three-armed CRT compares two well-established quality improvement interventions with usual practice. The two interventions comprise: provision of clinical practice guidelines with prompts and audit-based education.The study population will be all individuals with CKD from general practices in eight localities across England. Randomisation will take place at the level of the general practices. The intended sample (three arms of 25 practices) powers the study to detect a 3 mmHg difference in systolic BP between the different quality improvement interventions. An additional 10 practices per arm will receive a questionnaire to measure any change in confidence in managing CKD. Follow up will take place over two years. Outcomes will be measured using anonymised routinely collected data extracted from practice computer systems. Our primary outcome measure will be reduction of systolic BP in people with CKD and hypertension at two years. Secondary outcomes will include biomedical outcomes and markers of quality, including practitioner confidence in managing CKD.A small group of practices (n = 4) will take part in an in-depth process evaluation. We will use time series data to examine the natural history of CKD in the community. Finally, we will conduct an economic evaluation based on a comparison of the cost effectiveness of each intervention.Clinical Trials RegistrationISRCTN56023731. ClinicalTrials.gov identifier.

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.

Serum Phosphate as a Risk Factor for Cardiovascular Events in People with and without Chronic Kidney Disease: A Large Community Based Cohort Study

Background Serum phosphate is a known risk factor for cardiovascular events and mortality in people with chronic kidney disease (CKD), however data on the association of these outcomes with serum phosphate in the general population are scarce. We investigate this relationship in people with and without CKD in a large community-based population. Methods Three groups from an adult cohort of the Quality Improvement in Chronic Kidney Disease (QICKD) cluster randomised trial (ISRCTN56023731) were followed over a period of 2.5 years: people with normal renal function (N = 24,184), people with CKD stages 1–2 (N = 20,356), and people with CKD stages 3–5 (N = 13,292). We used a multilevel logistic regression model to determine the association between serum phosphate, in these groups, and a composite outcome of all-cause mortality, cardiovascular events, and advanced coronary artery disease. We adjusted for known cardiovascular risk factors. Findings Higher phosphate levels were found to correlate with increased cardiovascular risk. In people with normal renal function and CKD stages 1–2, Phosphate levels between 1.25 and 1.50 mmol/l were associated with increased cardiovascular events; odds ratio (OR) 1.36 (95% CI 1.06–1.74; p = 0.016) in people with normal renal function and OR 1.40 (95% CI 1.09–1.81; p = 0.010) in people with CKD stages 1–2. Hypophosphatemia (<0.75 mmol/l) was associated with fewer cardiovascular events in people with normal renal function; OR 0.59 (95% CI 0.36–0.97; p = 0.049). In people with CKD stages 3–5, hyperphosphatemia (>1.50 mmol/l) was associated with increased cardiovascular risk; OR 2.34 (95% CI 1.64–3.32; p<0.001). Other phosphate ranges were not found to have a significant impact on cardiovascular events in people with CKD stages 3–5. Conclusions Serum phosphate is associated with cardiovascular events in people with and without CKD. Further research is required to determine the mechanisms underlying these associations.

Quality-improvement strategies for the management of hypertension in chronic kidney disease in primary care: a systematic review.

BACKGROUND Chronic kidney disease (CKD) is a relatively recently recognised condition. People with CKD are much more likely to suffer from cardiovascular events than progress to established renal failure. Controlling systolic blood pressure should slow the progression of disease and reduce mortality and morbidity. However, no systematic review has been conducted to explore the effectiveness of quality-improvement interventions to lower blood pressure in people with CKD. AIM To assess the effectiveness of quality-improvement interventions to reduce systolic blood pressure in people with CKD in primary care, in order to reduce cardiovascular risk and slow the progression of renal disease. METHOD Papers were identified from the trial data bases of the Cochrane Effective Practice and Organisation of Care Group (EPOC) and Cochrane renal groups. In a three-round process, at least two investigators read the papers independently. Studies were initially excluded based on their abstracts, if these were not relevant to primary care. Next, full papers were read, and again excluded on relevance. Quantitative and, where this was not possible, qualitative analyses of the findings were performed. RESULTS The selected studies were usually carried out on high-risk populations including ethnic minorities. The interventions were most often led by nurses or pharmacists. Three randomised trials showed a combined effect of a reduction in systolic blood pressure of 10.50 mmHg (95% confidence interval [CI] = 5.34 to 18.41 mmHg). One non-randomised study showed a reduction in systolic blood pressure of 9.30 mmHg (95% CI = 3.01 to 15.58 mmHg). CONCLUSION Quality-improvement interventions can be effective in lowing blood pressure, and potentially in reducing cardiovascular risk and slowing progression in CKD. Trials are needed in low-risk populations to see if the same improvements can be achieved.

Predicting the prevalence of chronic kidney disease in the English population: a cross-sectional study

BackgroundThere is concern that not all cases of chronic kidney disease (CKD) are known to general practitioners, leading to an underestimate of its true prevalence. We carried out this study to develop a model to predict the prevalence of CKD using a large English primary care dataset which includes previously undiagnosed cases of CKD.MethodsCross-sectional analysis of data from the Quality Improvement in CKD trial, a representative sample of 743 935 adults in England aged 18 and over. We created multivariable logistic regression models to identify important predictive factors.ResultsA prevalence of 6.76% was recorded in our sample, compared to a national prevalence of 4.3%. Increasing age, female gender and cardiovascular disease were associated with a significantly increased prevalence of CKD (p < 0.001 for all). Age had a complex association with CKD. Cardiovascular disease was a stronger predictive factor in younger than in older patients. For example, hypertension has an odds ratio of 2.02 amongst patients above average and an odds ratio of 3.91 amongst patients below average age.ConclusionIn England many cases of CKD remain undiagnosed. It is possible to use the results of this study to identify areas with high levels of undiagnosed CKD and groups at particular risk of having CKD.Trial registrationCurrent Controlled Trials ISRCTN: ISRCTN56023731. Note that this study reports the results of a cross-sectional analysis of data from this trial.

Association of anaemia in primary care patients with chronic kidney disease: cross sectional study of quality improvement in chronic kidney disease (QICKD) trial data

BackgroundAnaemia is a known risk factor for cardiovascular disease and treating anaemia in chronic kidney disease (CKD) may improve outcomes. However, little is known about the scope to improve primary care management of anaemia in CKD.MethodsAn observational study (N = 1,099,292) with a nationally representative sample using anonymised routine primary care data from 127 Quality Improvement in CKD trial practices (ISRCTN5631023731). We explored variables associated with anaemia in CKD: eGFR, haemoglobin (Hb), mean corpuscular volume (MCV), iron status, cardiovascular comorbidities, and use of therapy which associated with gastrointestinal bleeding, oral iron and deprivation score. We developed a linear regression model to identify variables amenable to improved primary care management.ResultsThe prevalence of Stage 3–5 CKD was 6.76%. Hb was lower in CKD (13.2 g/dl) than without (13.7 g/dl). 22.2% of people with CKD had World Health Organization defined anaemia; 8.6% had Hb ≤ 11 g/dl; 3% Hb ≤ 10 g/dl; and 1% Hb ≤ 9 g/dl. Normocytic anaemia was present in 80.5% with Hb ≤ 11; 72.7% with Hb ≤ 10 g/dl; and 67.6% with Hb ≤ 9 g/dl; microcytic anaemia in 13.4% with Hb ≤ 11 g/dl; 20.8% with Hb ≤ 10 g/dl; and 24.9% where Hb ≤ 9 g/dl. 82.7% of people with microcytic and 58.8% with normocytic anaemia (Hb ≤ 11 g/dl) had a low ferritin (<100ug/mL). Hypertension (67.2% vs. 54%) and diabetes (30.7% vs. 15.4%) were more prevalent in CKD and anaemia; 61% had been prescribed aspirin; 73% non-steroidal anti-inflammatory drugs (NSAIDs); 14.1% warfarin 12.4% clopidogrel; and 53.1% aspirin and NSAID. 56.3% of people with CKD and anaemia had been prescribed oral iron. The main limitations of the study are that routine data are inevitably incomplete and definitions of anaemia have not been standardised.ConclusionsMedication review is needed in people with CKD and anaemia prior to considering erythropoietin or parenteral iron. Iron stores may be depleted in over >60% of people with normocytic anaemia. Prescribing oral iron has not corrected anaemia.