Abstract
Background:
Patients with diabetes and chronic kidney disease (CKD) are at high risk of diabetes-related complications. Diabetes care can support these individuals, but outpatient clinic appointments can be difficult to attend, given their already high burden of multimorbidity.
Methods:
We systematically searched the medical and grey literature for studies that evaluated the effect of nonconventional diabetes care strategies on diabetes-related outcomes in adults with stages 2–5 CKD or using dialysis (end of search December 30, 2017). We included both randomized-controlled trials and observational studies. Study selection and data extraction were completed by two independent reviewers. Diabetes-related outcomes included glycemic, blood pressure, and lipid control, along with microvascular complications, macrovascular complications, and death.
Results:
After screening 2177 relevant citations, we identified 34 studies which met inclusion. The majority were observational studies. Studies were frequently small, single-centered, and excluded patients with more advanced CKD. Nonconventional diabetes care strategies included community-based care, unique self-management and education programs, nurse-led care clinics, dialysis-based diabetes programs, telemedicine, and interdisciplinary care clinics. Programs were most often developed by study investigators. Although there were limitations to several of the included studies, programs were described to have modest effects on physiologic outcomes, and in some cases, diabetes-related complications and death.
Conclusions:
Nonconventional diabetes-related care might be helpful to patients with CKD. Prior to developing and implementing programs, however, it will be important to study them more rigorously, understand their acceptability to patients, and evaluate their costs and feasibility in a real-world setting.
Introduction
The prevalence of multimorbidity is increasing among patients with diabetes. It is estimated that most adults with diabetes now live with at least one comorbid chronic disease, and as many as 40% have three or more other medical conditions. 1 –3
Patients who live with diabetes and chronic kidney disease (CKD) are an especially vulnerable population. Compared with those without kidney disease, they struggle with dysglycemia and are at increased risk of microvascular disease, macrovascular disease, and even death. 4 –6 Glycemic management, diabetes education, dietary counseling, and screening for diabetes-related complications can be helpful to these individuals. 7,8
Traditionally, diabetes-related care is provided to patients at separate outpatient clinic appointments with physicians and allied health professionals (i.e. certified diabetes educators, dieticians) every 3–6 months. For patients with CKD and diabetes who live with many other medical comorbidities, these additional clinic appointments can be difficult to attend and can add to an already high burden of health care. At busy outpatient clinic appointments, health-care providers can also struggle to fully address their complex needs. 1
Nonconventional diabetes care strategies (i.e. diabetes care that is not delivered at traditional outpatient clinic appointments with physicians, diabetes educators, or dieticians), might better support these vulnerable individuals. To our knowledge, there has been no previous effort to systematically identify and describe the effect of these strategies on diabetes-related outcomes in patients with CKD. A thorough review of the literature is important, as we look toward new alternatives to manage complex patients in a patient-centered manner.
Scoping reviews of the literature can help investigators to examine the extent, range, and nature of available evidence. 9 We conducted a scoping review of studies which evaluated the effect of nonconventional diabetes care strategies on diabetes-related outcomes in adults aged ≥ 18 years with diabetes and CKD. Our primary aims were to: (1) understand the breadth of nonconventional diabetes-related care strategies and (2) ascertain how these programs were developed and implemented. Our secondary aim was to determine the effect of these programs on diabetes-related outcomes (i.e. metabolic control (glycemic control, blood pressure, and lipid control), microvascular complications, macrovascular complications, and death).
Methods
Design
We conducted our review using the methods suggested by Arksey, Levac, and Tricco (PRISMA-ScR). 10,11 Our processes were guided by an internal, unpublished protocol.
Patients
We included studies of adults aged ≥ 18 years with CKD and diabetes (type 1 or 2). We defined CKD as stages 2–5 disease (i.e. an estimated glomerular filtration rate (eGFR) < 90 ml/min/1.73 m2), the presence of micro or macroalbuminuria, receipt of dialysis, or an investigator diagnosis of CKD.
Diabetes care strategies
We defined nonconventional diabetes care strategies as those where diabetes-related care was provided outside of a traditional outpatient clinic appointment with a physician, diabetes educator, or dietician. Diabetes-related care was defined as the management of glycemia, blood pressure, and lipids; screening for related complications (i.e. microvascular or macrovascular disease); self-management support and education.
Control
Included studies could either have or not have a control group.
Outcomes
Diabetes-related outcomes included physiological outcomes (glycemic, lipid, blood pressure control), microvascular outcomes (retinopathy or blindness, decline in kidney function or progression to renal replacement therapy, neuropathy, gastroparesis, erectile dysfunction, autonomic dysfunction), macrovascular outcomes (myocardial infarction, heart failure, stroke, amputation, ulcers), and death.
Study design
We included both randomized-controlled trials (RCTs) and non-randomized studies (e.g. cohort, case-control, pre- and post-intervention studies).
Identification of studies
We first consulted an experienced health sciences librarian (BD) to develop a comprehensive search strategy. This strategy included a combination of key words and Medical Subject Heading (MeSH) terms that were consistent with our research aims and study population (Table 1 of the Online Supplementary Material). We validated our final search strategy through the retrieval of a key set of previously identified relevant articles.
We next searched electronic databases including MEDLINE, EMBASE, CINAHL, Cochrane Library, Scopus, BIOSIS, and Web of Science for relevant citations published until October 6, 2017 (no start date). We then reviewed the reference lists of all included studies and used the Related Articles feature in PubMed to identify additional citations. Further, using similar search terms (e.g. nontraditional, diabetes), we searched Google for relevant citations up to December 30, 2017. We completed each search strategy in Google within a single browsing session.
Two reviewers (K.K.C and V.K) independently screened the titles and abstracts of all identified citations against selection criteria and categorized them as include, exclude, or uncertain. We decided a priori to include studies where only a subgroup of patients had both CKD and diabetes, if at least one diabetes-related outcome was reported for the subgroup. If multiple studies reported outcomes for a similar group of patients (e.g. if studies published both short- and long-term outcomes in separate papers for one patient group), we included the longer term study. We excluded studies not written in English, case reports, case series, clinical practice guidelines, reviews, and commentaries. We pilot tested the first 10 citations for consistency and clarity of our selection criteria.
We then retrieved full text articles for those studies that we deemed to include, as well as those we were uncertain about including. All full text articles were reviewed against our selection criteria. Reviewers communicated regularly through the study selection process. If there were discrepancies about whether to include a study, we resolved them by consensus. If no resolution could be attained, a third party resolved the discrepancies (S.M.R). A flow diagram of study inclusion and exclusion is detailed in Figure 1 of the Online Supplementary Material.
Charting and summarizing the data
Reviewers used standard forms to abstract the characteristics of all included studies (design, country, publication year), along with their population, intervention, outcomes, and relevant results. Given the heterogeneity of included studies, we presented our results descriptively.
Reviewers completed their charting independently. We pilot tested the first 10 articles to ensure that our data abstraction was consistent and made necessary changes prior to abstracting the remaining articles.
Results
Of the 2177 unique citations identified in our literature search, 34 studies met inclusion. 12 –45 The characteristics of included studies are noted in Table 1, and study outcomes and results are reported in Table 2.
Characteristics of included studies.
DM: diabetes mellitus; CKD: chronic kidney disease; RCT: randomized controlled trial; HTN: hypertension; BP: blood pressure; P. cohort: prospective cohort; ACR: albumin to creatinine ratio; A1c: hemoglobin A1c; eGFR: estimated glomerular filtration rate; GP: general practitioner; NR: not reported; SBP: systolic blood pressure; DBP: diastolic blood pressure; CVD: cardiovascular disease; LDL: low-density lipoprotein; RRT: renal replacement therapy; PD: peritoneal dialysis; CGM: continuous glucose monitoring; HD: hemodialysis; ESRD: end-stage renal disease.
aOnly a subgroup of the study population had CKD and DM.
Study outcomes and results.
BP: blood pressure; CVD: cardiovascular disease; CKD: chronic kidney disease; DM: diabetes mellitus; eGFR: estimated glomerular filtration rate; A1c: hemoglobin A1c; BP: blood pressure; LDL: low-density lipoprotein; HDL: high-density lipoprotein; SBP: systolic blood pressure; ACR: albumin to creatinine ratio; DBP: diastolic blood pressure; HD: hemodialysis; ESRD: end-stage renal disease; PY: person-years; RRT: renal replacement therapy; CGM: continuous glucose monitoring; PVD: peripheral vascular disease.
There were 7 RCTs, 12,19,24,31,35,40,44 one cluster RCT, 15 19 observational cohort/case-control studies, 13,14,16,17,21–23,25–29,32,34,37–39,41,42,45 and 7 pre- and post-intervention studies included. 18,20,26,30,33,36,43 Studies were conducted in Australia, 44 Brazil, 32 Canada, 12,13,34,38 France, 36,37 Germany, 23 Hong Kong, 27 Japan, 22,28 Mexico, 26 the Netherlands, 24 New Zealand, 14,16,17 Singapore, 45 Sweden, 20 Thailand, 15 the United Kingdom, 18,21,30,33 and the United States. 19,25,29,31,35,39–43 Most studies included fewer than 100 participants with stages 2–4 CKD and diabetes. The majority excluded patients with stage 5 disease or using dialysis. Some reported high losses to follow-up. 26,42
We categorized nonconventional care programs using the Cochrane Effective Practice and Organization of Care (EPOC) taxonomy. 46 This taxonomy classifies health system interventions into groups based upon conceptual or practical similarities. 46 We grouped programs into community-based care (i.e. outreach service), unique diabetes self-management support and education, nurse-led care clinics (i.e. role expansion), interdisciplinary care clinics (i.e. team care), dialysis-based diabetes care programs (i.e. site of service delivery), and telemedicine strategies. If programs had overlapping features (e.g. community-based care program was led by a nurse), we used their location of delivery to categorize them. Most of the programs were developed by research investigators. Only four studies included patients in their program development, implementation, or evaluation. 18,21,22,44
Community-based care
Community-based diabetes care programs brought diabetes support to patients’ homes, community clinics, or primary care practices. Most interventions were developed for Indigenous populations. 12,14,16 Most studies were small and observational in design. 12 –18
These programs were multifaceted and included protocol guided blood pressure management, glycemic support and education, and self-management support. Nurses most often administered the program with the support of a medical specialist if needed. Care was offered in person, up to once monthly.
Over the short term, community-based care programs were described to have a modest, positive effect on blood pressure, cholesterol, and glycemic control. A reduction in proteinuria was also described. Where evaluated, programs did not appear to have an effect on cardiovascular outcomes or death. 14
Self-management support/education
Nonconventional diabetes self-management support and education programs aimed to help participants adopt healthier lifestyles and self-manage their disease and treatments. However, rather than delivering self-management support traditionally (i.e. at an outpatient education appointment), studies evaluated the effect of printed materials and videos, group counseling, and devices (e.g. Palm Pilots) on patient outcomes. Self-management support programs were administered by allied health professionals, and contact was offered to participants up to once weekly. Most of the programs aimed to improve glycemic control or blood pressure. Studies were small and most often observational in design. 19–23,44
Over the short term, programs were described to have small positive effects on glycemic control, blood pressure control, and kidney function. In one study where participants learned to self-manage and self-titrate their own blood pressure medications, there may have been beneficial effects on renal outcomes (i.e. the need for renal replacement therapy), amputation, blindness, and death. 23
Nurse-led care clinics
Two small studies evaluated the effect of nurse-led care clinics on diabetes-related outcomes. At outpatient appointments, nurses adjusted participants’ cardioprotective (i.e. blood pressure and lipid-lowering agents) and glycemic medications, conducted diabetes-related screening (e.g. foot screening), and provided education, adherence, and self-management support. Clinic visits were offered up to twice per month.
Over the short term, nurse-led care was described to have beneficial effects on glycemia, blood pressure, lipid control, and kidney function. Their effect on other microvascular outcomes, macrovascular outcomes, or death was not described. 24,25
Interdisciplinary care clinics
Interdisciplinary care clinics were the most frequent care strategy studied. These clinics brought health-care professionals together to provide diabetes-related care at a single outpatient visit. The majority of studies were observational, but included more participants than studies of other programs. 26–34,45
At their appointments, participants had their cardioprotective and glycemic medications adjusted, were screened for diabetes-related complications, and were offered self-management support. Appointments were offered up to once per month, and in some cases, remotely between clinic visits (i.e. telephone support). In some studies, routine interdisciplinary team meetings were also held to discuss participant cases.
Interdisciplinary care may have had beneficial effects on glycemic, lipid, blood pressure control, and kidney function. Where studied, cardiovascular outcomes, end-stage kidney disease, amputations, and mortality may have been lower in participants who were part of interdisciplinary care clinics.
Telemedicine
Telemedicine strategies used telecommunications to deliver diabetes-related health services to patients (i.e. technology, telephone-based support). 35 –37
In two small studies, patients wore continuous glucose monitoring (CGM) devices, and blood sugars were sent remotely to care providers for glycemic medication adjustment. Another randomized controlled study offered remote, interprofessional care to patients via a telemedicine device.
Short-term improvements in glycemic control (i.e. 3 months) was reported in CGM studies. Remote interprofessional care did not appear to reduce the risk of microvascular outcomes, macrovascular outcomes, or death in patients with CKD and diabetes.
Dialysis-based diabetes care
Dialysis-based diabetes care strategies offered care to patients during hemodialysis sessions. Studies of these programs were small, observational, and often did not involve a control group. 38 –43
The majority were foot care programs where patients received education and had their feet examined while dialyzing. One study offered multifactorial diabetes care to patients in the dialysis unit (i.e. glycemic control, self-management support, foot care). 40 Support was offered up to weekly, by hemodialysis nurses and in-unit diabetes case managers.
Programs may have had beneficial effects on glycemic control, ulcers, amputations, and death.
Discussion
Twenty-five to 50% of patients with diabetes live with CKD. 8 Where the prevalence of multimorbidity will only continue to increase, 1 it is important to evaluate new strategies to provide these complex individuals with patient-centered health care.
We conducted a comprehensive scoping review of the medical and grey literature to systematically identify and describe nonconventional diabetes-related care strategies and their effects on diabetes-related outcomes in adults with diabetes and CKD. We found that unique self-management and education programs, telemedicine, dialysis-based diabetes care, nurse-led care clinics, interdisciplinary care clinics, and community-based care programs have been evaluated in some patients with diabetes and stages 2–4 CKD. Care programs were most often developed by study investigators and were in some cases time and resource-intensive (e.g. offered care up to once weekly, used telemedicine technology).
Programs were described to have beneficial effects on glycemic, lipid, blood pressure control, and kidney function. However, studies were limited in their design (observational, lack of control), involved a small number of participants (typically < 100), and were short in duration. Where RCTs of programs were conducted, community-based diabetes care, self-management education programs, and interdisciplinary care clinics had reported benefits.
Based upon our review, we might suggest that prior to developing, implementing, or continuing these programs (i.e. in centers that may already have access to nonconventional strategies), it might be beneficial to study these strategies as part of large RCTs. Given the complexity of some programs, it would also be important to understand their feasibility on a larger scale because of their resource and time requirements. 47 Finally, given low participant numbers and often high dropout rates in some studies, consideration should be given to involving patients in program design. This might ensure that interventions address patient values and their cultural and psychosocial needs. This may better promote patient adherence to interventions. 47
Strengths and limitations
We conducted a comprehensive review and abstracted study data using standardized processes and structured tools. We screened and abstracted citations in duplicate. We summarized the characteristics of studies and interventions, and we noted any beneficial effects on diabetes-related outcomes.
There are limitations to discuss. Our review was a scoping review rather than a systematic review. As such, we included all levels of evidence (i.e. did not restrict to RCTs). Although we commented upon some of the limitations of included studies, we did not formally evaluate their quality. 11,48 We also excluded non-English studies and we were lenient in our definition of CKD. CKD is typically defined by an eGFR < 60 ml/min/1.73 m2 or microalbuminuria lasting >3 months. Some studies did not report these definitions per se, and as such, some patients may have been misclassified with this condition.
Although we used broad search terms, due to the nature of our research question, we may not have identified all nonconventional strategies. We used the EPOC taxonomy to classify care programs but recognize that some programs had overlapping features (i.e. nurse-led clinics also offered self-management strategies). We did summarize study characteristics and outcomes, but were unable to draw conclusions about the most effective care strategies for adult patients with diabetes and CKD.
Conclusions
Small, frequently observational studies, have described that nontraditional diabetes care strategies might potentially be effective for patients with diabetes and CKD. We suggest that before developing and studying new ways of caring for patients with multimorbidity, patients should be included in program development, they should be studied in a randomized-controlled fashion, and the feasibility and health economic benefit of these programs should be explored in a real-life setting.
Supplemental material
Supplementary_Material_JOC - Nonconventional diabetes-related care strategies for patients with chronic kidney disease: A scoping review of the literature
Supplementary_Material_JOC for Nonconventional diabetes-related care strategies for patients with chronic kidney disease: A scoping review of the literature by Kristin K Clemens, Vinusha Kalatharan, Bridget L Ryan, and Sonja Reichert in Journal of Comorbidity
Footnotes
Acknowledgment
The authors would like to thank Brad Dishan (BD) for developing the search strategy and conducting the literature search.
Declaration of conflicting interests
The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Unrelated to this work, Kristin Clemens received a Diabetes Canada Junior Investigator Award supported by AstraZeneca in 2017. She has also received travel and conference support from Merck. Unrelated to this work, Sonja Reichert has participated in an investigator-initiated research grant from Sanofi. She has also received personal fees for presentations and participation in advisory boards from Sanofi, AstraZeneca, Novo Nordisk, Boehringer Ingelheim, Servier, Janssen, Eli Lilly, Merck, and Abbott. There are no other conflicts of interest to disclose.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Canadian Institutes of Health Research/Strategy for Patient Oriented Research through a Patient Oriented Research Collaboration Grant. The work of Vinusha Kalatharan was supported by a Canadian Institutes of Health Research Doctoral Scholarship and a Doctoral Scholarship from the KRESCENT Program.
Supplemental material
Supplemental material for this article is available online.
References
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