MNT: RDN in Medical Team (2015)

Citation:
Bray P, Cummings DM, Morrissey S, Thompson D, Holbert D, Wilson K, Lukosius E, Tanenberg R. Improved outcomes in diabetes care for rural African Americans. Annals of Family Medicine. 2013; 11 (2): 145-150.  PubMed ID: 23508601
 
Study Design:
Non-Randomized Controlled Trial
Class:
C - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
To determine effectiveness of a fee-for-service, primary care practice offering interprofessional care management on intermediate and long-term glycemic control, blood pressure and lipid levels for African American patients with type 2 diabetes.
Inclusion Criteria:
  • Attendance at selected fee-for-services primary care practices in rural counties as defined by the U.S. Census Bureau
  • Type II diabetes diagnosis
  • Signed informed consent.
Exclusion Criteria:
  • No type 2 diabetes diagnosis
  • Not a patient at selected primary care practices.
Description of Study Protocol:

Recruitment

Recruited from rural primary care practices.

Design

In three purposively selected, rural, fee-for-service, primary care practices, African American patients with type 2 diabetes received point-of-care education, coaching and medication intensification from a diabetes care management team consisting of a nurse, pharmacist and dietitian. The six key elements of the intervention design included education with behavioral coaching, treatment intensification, point-of-care management, expanded roles of clinic staff to facilitate management, a team-care approach and physician leadership. As a control, African American patients from five randomly selected practices, matched for practice and patient characteristics, received usual care. The effects of the intervention on intermediate (median 18 months) and long-term (median 36 months) changes in glycated hemoglobin (hemoglobin A1C) levels, blood pressure and lipid levels as well as the proportion of patients meeting target values were evaluated.  

Intervention

Point-of-care diabetes care management involving education, self-management coaching and medication adjustment from a team, including a nurse case manager, pharmacist and dietitian.

Statistical Analysis

  • Descriptive statistics (means and T-tests for continuous variables; proportions and X2 statistics for categorical variables) were used to characterize the study patients' demographic characteristics and diabetes-specific outcome measures at baseline
  • Intention to treat analysis used
  • Univariate analysis completed by independent samples T-tests were used to compare intervention and control outcome means
  • X2  analysis was used to evaluate the number and percentage of patients who met target goals at baseline and at the intermediate and final evaluations
  • Linear mixed-modeling strategy to examine change in hemoglobin A1C 
  • Multivariate logistic regression
  • Economic analysis.
Data Collection Summary:

Timing of Measurements

Collected by unblinded staff at baseline, 18 months (intermediate) and 36 months (long-term):
  • Demographic characteristics including age, sex, insurance, duration of diabetes
  • Height
  • Weight
  • Blood pressure using standard procedures
  • Blood specimen measuring total cholesterol, low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL) and glycemic control (hemoglobin A1C).

Dependent Variables

  • Blood pressure using standard procedures
  • Blood specimen measuring total cholesterol, low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL) and glycemic control (hemoglobin A1C).

Independent Variables

Method of diabetes care management.

Control Variables

  • Demographic characteristics including age, sex, insurance, duration of diabetes
  • Height
  • Weight.
Description of Actual Data Sample:
  • Initial N: N=727 subjects
  • Attrition (final N): N=676 subjects (intervention group, 66% female and 34% male; control group, 63% female and 37% male)
  • Age: Ages 59.5±12 years for intervention group, 60.6±12.4 years for control group
  • Ethnicity: African American
  • Other relevant demographics: No statistically significant differences in demographics between subjects in the intervention and control groups
  • Anthropometrics: No statistically significant differences in baseline clinical parameters between subjects in the intervention and control groups
  • Location: North Carolina, United States.

 

Summary of Results:

Key Findings
 

  • Mean hemoglobin A1C levels decreased significantly more from baseline to the 18 month (P<0.05) and the 36 month (P<0.05) follow-up among intervention practice subjects than among control subjects
  • Mean change in LDL-cholesterol and HDL-cholesterol values in intervention practice patients was significantly greater than in control practice patients in univariate comparisons
  •  Significantly greater percentage of patients in the intervention subjects achieved a hemoglobin A1C value near 7.0% at the final assessment (P<0.01)
  • Proportion of subjects achieving a systolic blood pressure of less than 140mm Hg was substantially greater in the intervention practices at 18 months and 36 months
  • In multivariate linear modeling, the mean decrease in hemoglobin A1C levels from baseline to final follow-up for intervention practice subjects was significantly greater when compared with control practice subjects (F(v1, v6)=17.97; P=0.005) even when controlling for other variables.
Comparison of Baseline Values and Intermediate and Long-term Changes in Clinical Outcome Measure

 

  Control Practice (N=359 Patients)
Mean (SD)
Intervention Practice (N=368)
Mean (SD)
  Baseline 18 Months 36 Months Baseline 18 Months 36 Months
Hemoglobin A1C (%) 7.9 (2.2) 7.7 (1.9) 7.8 (2.0) 7.9 (2.1) 7.4 (1.6)a 7.4 (1.9)b
Systolic/diastolic blood pressure (mm Hg) 138 (18) 139 (16) 140 (17) 135 (16) 135 (14) 135 (16)
Diastolic blood pressure (mm Hg) 81 (10) 80 (9) 79 (10) 79 (8) 78 (9) 78 (9)
LDL-cholesterol (mg per dL) 101 (36) 99 (38) 97 (32) 105 (33) 95 (32) 99 (36)a
HDL-cholesterol (mg per dL) 50 (13.3) 51 (13,4) 50 (13.3) 50 (12.7) 50 (13.6) 52 (13.9)a
Total cholesterol (mg per dL) 176 (39.7) 177 (42.5) 170 (38.1) 182 (38.1) 171 (37.7) 176 (39.1)

 

 

a P<0.05 in univariate comparison of change, b P<0.005 in multivariate model comparison, c P<0.01 in univariate comparison.

Multivariate Model of Change in Hemoglobin A1C Level from Baseline to Final Follow-up

  Multivariate Linear Model Multivariate Logistic Regression Model Change in Percentage with HbA1C 7.5% or More
Variable Model Parameter (Standard Error) Effect P-value Odds Ratio 95% Confidence Ratio
Age 0.022 (0.006) <0.001 1.041 1.007 to 1.075
Sex 0.184 (0.138) Not Significant 0.804 0.356 to 1.818
Duration of diabetes -0.026 (0.01) 0.009 0.998  0.955 to 1.043
Number of visits per year 0.008 (0.029) Not significant 1.08  0.898 to 1.3
Baseline HbA1C  level 0.606 (0.3) <0.001 0.417  (0.308 to 0.564)
Intervention vs. control clinic effect   0.005 0.393 0.156 to 0.988
















 


Other Findings

  • Mean duration of diabetes:
    • Intervention group: 13±6.4 years
    • Control group: 11±7.2 years
  • A total of 1.6 full-time equivalent coach educators covered an annual diabetes panel of 1,280 patients at the cost of approximately $115 per patient per year.
Author Conclusion:
In a study of primary care practices based in rural communities with high rates of poverty and with high risk African Americans who have established type II diabetes and traditionally poor outcomes, redesigning diabetes care to incorporate interprofessional care management results in significantly greater intermediate and long-term improvement in glycemic control. Modest improvements in the proportion of patients with systolic blood pressure less than 140mm Hg and small but significant changes in mean LDL-cholesterol and HDL-cholesterol levels.
Funding Source:
Not-for-profit
Robert Wood Johnson Foundation, Kate B Reynolds Charitable Trust, Roanoke Chowan Foundation
Foundation associated with industry:
Other non-profit:
Reviewer Comments:
Limitations of the study include purposeful selection of intervention sites and lack of information on medication adherence or treatment intensification and patient satisfaction or the impact of these components on the intervention.
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? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) No
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? Yes
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  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? Yes
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? N/A
  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? No
  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)? Yes
  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? Yes
  10.2. Was the study free from apparent conflict of interest? Yes