MNT: RDN in Medical Team (2015)


Thanamayooran S, Rose C, Hirsch DJ. Effectiveness of a multidisciplinary kidney disease clinic in achieving treatment guideline targets. Nephrology Dialysis Transplantation, 2005; 20: 2,385-2,393.

PubMed ID: 16046506
Study Design:
Time Study
C - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
To provide a report after four years of follow-up in a cohort of patients, after nephrologists working in a multi-disciplinary clinic provided ongoing care. 
Inclusion Criteria:
  • New patients seen in 1998 and 1999 by nephrologists at the Queen Elizabeth II Health Center in Halifax, Nova Scotia
  • Serum creatinine over 140mcmol per L (1.6mg per dL) in men or 105mcmol per L (1.2mg per dL) in women. These values correspond to a glomerular filtration rate (GFR) of 60ml per minute.
Exclusion Criteria:
Met with a nephrologist in the past.
Description of Study Protocol:

Recruited from the Queen Elizabeth II Health Science Centre in Halifax, Nova Scotia.


  • The cohort of patients were analyzed in historical prospective fashion to determine the adequacy of control of blood pressure, metabolic control and dialysis access placement by the kidney disease clinic. Also, the effectiveness of the clinic to achieve K/DOQI standards of care was evaluated.  
  • Ongoing care was provided in the setting of a tertiary care university multi-disciplinary nephrology clinic, with ongoing involvement of nurses and nurse educators, social workers, dietitians and full-time academic nephrologists
    • Patients were generally seen in the clinic annually for GFR 30ml to 60ml per minute, every six months for GFR 15ml to 30ml per minute and every three months for GFR less than 15ml per minute
    • No private practice fee-for-service remunerated physicians were involved and the Canadian Medicare system provided all medical or surgical and ancillary care free of charge to the patients, including dialysis.

Blinding Used

Care at a multi-disciplinary kidney disease clinic.

Statistical Analysis

  • Analysis of variance (ANOVA) tests used to test differences in numeric data across years (baseline to four years of follow-up)
  • ANOVA tests run to determine if differences of laboratory means existed across stages of kidney disease
  • In an attempt to identify possible bias introduced by variable follow up duration due to patient drop-out, means for blood pressure, serum calcium, phosphate, calcium-phosphate product, bicarbonate and hemoglobin at presentation were compared using ANOVA
  • Wilcoxon rank sum test used to compare differences in mean time to therapy between fistula and catheter patients
  • Paired T-tests were used to calculate differences in numeric variables from baseline to follow-up
  • Kaplan-Meier curves were used to estimate time to RRT, stratified by level of creatinine clearance; X2 analyses were then used to evaluate certain possible associations with RRT
  • P<0.05 was significant.
Data Collection Summary:

Timing of Measurements

Data collected from initial and follow-up visit records (clinic visit closest to annual interval from initial visit up to last visit or dialysis start)
  • Blood pressure
  • Weight
  • Medications
  • Stage of CKD
  • Laboratory data including calcium, phosphorus, calcium x phosphorus, creatinine clearance, hemoglobin, serum bicarbonate
  • Use of renal replacement therapy
  • Dialysis access planning.

Dependent Variables

  • Blood pressure
  • Weight
  • Medications
  • Stage of CKD
  • Laboratory data including calcium, phosphorus, calcium x phosphorus, creatinine clearance, hemoglobin, serum bicarbonate
  • Use of renal replacement therapy
  • Dialysis access planning.

Independent Variables

Care at multi-disciplinary kidney disease clinic.

Control Variables

  • Etiology of kidney disease
  • Outcome of patients no longer followed in clinic.
Description of Actual Data Sample:
  • Initial N: 340 patients (185 male, 155 female)
  • Attrition (final N): 31% at one year (N=234); 80% at four years (N=70)
  • Age: 66.6±15.2 years at initial visit
  • Ethnicity: Not described
  • Other relevant demographics: Diabetes and atherosclerotic nephropathy accounted for half of the etiology of chronic renal failure 
  • Anthropometrics: Discussed in results section
  • Location: Nova Scotia, Canada.
Summary of Results:

Key Findings

  • Demographics
    • Number of patients analyzed at initial visit: 340; 234 at one year, 144 at two years, 100 at three years and 70 at four years
    • Mean creatinine for each year of follow-up for the cohort remained statistically similar with an overall mean of 274±160mcmol per L
    • At presentation, six patients had stage 1 disease, 31 patients had stage 2 disease, 128 patients had stage 3 disease, 105 patients had stage 4 disease and 70 patients had stage 5 disease.
  • Blood pressure
    • Control of BP appeared improved in those patients seen at subsequent visits compared with the full patient group seen at initial visit
    • There was a trend toward increasing numbers of medications being used over time in a subset of patients followed in clinic and more than 60% of patients taking ACEIs or ARBs at the end of four years.
  • Metabolic parameters and anemia
    • There was a strong correlation between all metabolic parameters and estimated creatinine clearance, such that as creatinine clearance fell serum calcium fell, while calcium-phosphate product and serum phosphorus rose along with parathyroid hormone (P<0.0001 for Pearson's R statistic)
    • Hemoglobin levels fell progressively with creatinine clearance (P<0.05 by ANOVA) and were significantly improved at follow-up in patients with stage 5 kidney disease.
  • Renal replacement therapy
    • Total of 84 (24%) patients had some form of RRT
    • Initial form of RRT was HD is 57% of patients, PD in 35% and pre-emptive transplantation in 8% of patients.
Mean Blood Pressure ± Standard Deviation by Duration of Follow-Up



Systolic Blood Pressure

Diastolic Blood Pressure





One Year




Two Years




Three Years
Four Years

*P<0.001 vs. all subsequent years by ANOVA

Metabolic Parameters and Anemia Control


Stage 3 CKD
CrCl 30-60ml/minute

Stage 4 CKD
CrCl 15-30ml/minute

Stage 5 CKD
CrCl 15ml/minute

Initial visit

Follow up visit Initial visit Follow up visit

Initial visit

Follow up visit

Number of Observations


258 105 165



Mean Calcium, mM


2.3±0.12 2.3±0.16 2.29±0.17



Percentage Calcium <2.1mM 2 2 13 11 26 18
Mean Phosphorus, mM 1.17±0.22 1.26±0.3 1.36±0.3 1.4±0.41 1.8±0.6 1.54±0.35
Percentage Phosphorus >1.6mM 3 12 17 21 53 43
Mean Calcium x Phosphorus, mM 2.74±0.51 2.92±0.69 3.1±0.62 3.18±0.87 3.97±1.35 3.5±0.84
Percentage Calcium x Phosphorus >4.44mM 1 2 2 5 23 15
Mean Bicarbonate, mM 26.3±3.0 25.6±3.5 24.9±3.5 24.5±3.6 22.3±4.9 22.8±3.4
Percentage Bicarbonate <20 mM 2 3 5 5 29 12
Mean Hemoglobin, g/L 124±17 123±16 117±18 116±18 100±18 107±13
Percentage Hemoglobin <100g/L 4 7 20 15 51 31
Author Conclusion:
  • The study indicates that attendance at a multi-disciplinary CKD clinic supervised by nephrologists was associated with apparent improvements in BP control, anemia management and mineral metabolism over patient status at referral
  • However, the multi-disciplinary model with nephrologists, nurse educators and dietitians was unable to achieve guideline recommended metabolic anemia, BP and access targets for a significant number of patients.
Funding Source:
Other: Not described
Reviewer Comments:
Study limitations include: 
  • Care was not fully by protocol, therefore allowing for practice variations within the clinic
  • Incomplete follow-up of incident population implies that patients followed over time necessarily represent only a sub-group of a full cohort selected by unknown factors
  • Unable to assume that findings can be generalized to other populations.
Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) Yes
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? Yes
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? N/A
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) N/A
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? N/A
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) N/A
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? N/A
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? Yes
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? Yes
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? Yes
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) Yes
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? N/A
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? N/A
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? Yes
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? Yes
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? Yes
  6.6. Were extra or unplanned treatments described? Yes
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? Yes
  6.8. In diagnostic study, were details of test administration and replication sufficient? N/A
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? Yes
  7.2. Were nutrition measures appropriate to question and outcomes of concern? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? Yes
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? Yes
  7.5. Was the measurement of effect at an appropriate level of precision? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? Yes
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? Yes
  8.1. Were statistical analyses adequately described and the results reported appropriately? Yes
  8.2. Were correct statistical tests used and assumptions of test not violated? Yes
  8.3. Were statistics reported with levels of significance and/or confidence intervals? Yes
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? No
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? No
  8.6. Was clinical significance as well as statistical significance reported? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? Yes
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? No
  10.2. Was the study free from apparent conflict of interest? Yes