Is Periodontitis the Missing Link? A Metaethnographic Review of Glycemic Control Measures by Nigerian Diabetologists

Diabetologists have always been aware of the adverse infect of infection on glycemic control. Periodontitis is a state of chronic subclinical inflammation exerting a similar adverse influence on glycemic control. The mortality of diabetes mellitus in Nigeria remains high despite attempts at “tight glycemic control” using diet, life style modification, oral hypoglycemic and insulin. Reported attainment of glycemic control is at times as low as 15%. The result of the failure in meeting glycemic control targets has taken in toll on the life of Nigerians and stretched our meager resources to the limits due to frequent admissions as a result hyperglycemic emergencies. These emergencies leave in their trail, reduced sexual function, microangiopathy and attendant end stage renal disease, blindness, limb amputations and death, Could lack of consideration for periodontitis be the missing link in the glycemic control protocols of Nigerian diabetologists? Using the search phrase Nigeria AND (diabetes OR diabetic OR diabetics), we conducted a search of existing literature in Cochrane Library, MEDLINE (PubMed), Mesh (MEDICAL SUBJECT HEADINGS (MeSH) databases. An initial number of 709 results were trimmed to 31 after application of inclusion criteria. We conducted a combination of metaethnography and narrative synthesis on the 31 studies and arrived at the hypotheses that the average Nigerian diabetologists appears UNAWARE of the link between glycemic control and periodontitis. Urgent training is recommended for Nigerian diabetologists through continuing education courses and collaboration with periodontologists. *Corresponding author: Solomon O. Nwhator , Independent researcher, Formerly at Department of Preventive & Community Dentistry, Faculty of Dentistry, Obafemi Awolowo University, Ile-Ife, Nigeria, E-mail: periodontologist2010@gmail.com, nwhator32@yahoo.com Received November 28, 2011; Accepted February 13, 2012; Published February 15, 2012 Citation: Nwhator SO, Adedigba MA (2012) Is Periodontitis the Missing Link? A Metaethnographic Review of Glycemic Control Measures by Nigerian Diabetologists. Dentistry 2:121. doi:10.4172/2161-1122.1000121 Copyright: © 2012 Nwhator SO, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Background
Periodontitis is a state of chronic inflammation resulting in increased levels of proinflammatory mediators which increases insulin resistance resulting in poor glycemic control [1]. Periodontitis increases the risk of developing diabetes-associated complications by promoting the occurrence, progression and severity of diabetes [2]. Based on these findings, a team of German researchers have recommended that periodontal treatment should be part of the diabetes management protocol [2].
Unfortunately, Nigerian diabetologists appear to be completely unaware of this missing link in difficult glycemic control with dire consequences. Diabetic foot gangrene accounted for 55% of amputations at the Lagos University Teaching Hospital [3]. Poor glycemic control and consequent diabetic hyperglycemic emergencies accounted for the highest number diabetes-related admissions at the University of Ilorin Teaching Hospital [4] and diabetes mellitus accounted for 18% of endstage renal disease among Nigerians [5,6].
These sober statistics informed our decision to undertake this qualitative review as a preliminary step towards highlighting this costly omission by Nigerian diabetologists.

Review Question
The prevalence of diabetic hyperglycemic emergencies and attendant admissions and mortality [4] got us thinking of a missing link already explored in literature but virtually unknown among Nigerian diabetologists. We were concerned about the level of awareness of the link between chronic periodontitis and poor glycemic control among Nigerian diabetologists. We decided on this review to answer the following questions; 1. Is periodontal examination part of the current diabetes management protocol in Nigeria?
2. Do Nigerian diabetologists rule out chronic periodontitis in the management of poor glycemic control?
Being a qualitative review precluded the use of metaanalysis which is restricted to statistical of numerical outcomes of controlled clinical trials. We therefore settled for metasynthesis using the approach of a metaethnography of all available studies that met our inclusion criteria. Because of the ambiguities and lack of clear consensus on many aspects of a metaethnography, however, we decided to combine this review approach with a narrative synthesis as detailed in Table 1.

Deciding What is Relevant to the Initial Interest
Defining the focus of the synthesis A search on diabetes AND Nigeria yields thousands of unmanageable studies and distracts from our focus--consideration of an important factor in glycemic control--periodontitis. We realized that conducting a search on the attitudes of Nigerian diabetologists would also yield too few studies. To strike a balance therefore, we decided to focus on studies on the actions of diabetologists i.e., what they considered important while managing cases of difficult glycemic control or factors they considered important while instituting the socalled "tight glycemic control." This way, we attempted to read the "clinical mindset" of Nigerian diabetologists by investigating what clinical parameters they considered important while attempting to maintain "tight glycemic control." This decision yielded the dividends of more specific and better manageability of studies which helped us to quickly answer our review question.

Locating relevant studies
Locating relevant studies as an important part of deciding what is relevant to the initial interest. We searched Cochrane Library, MEDLINE (PubMed), Mesh (MEDICAL SUBJECT HEADINGS (MeSH) using the search phrase Nigeria AND (diabetes OR diabetic OR diabetics) (Table 2a).

Inclusion decisions/ criteria
we applied the limits set to "human," and "English" to the original 709 Pubmed hits to the search phrase Nigeria AND (diabetes OR diabetic OR diabetics). This streamlined the studies to 549. Adding the 32 hits from AJOL (African Journal Online) and Cochrane databases resulted in a total 590 studies. Further filtering of studies was performed using the term "glycemic control" and "control" resulting in 76 qualifying studies. To be included, a study had to be either an interventional study on glycemic control or one recommending interventions for tight glycemic control.
On these premises, 2 studies were excluded because they were written by dentists which were not diabetologists and 4 other studies were excluded because they were reviews not limited to Nigeria. The 2 case reports in our results were excluded due to the low evidence associated with such studies while 37 separate studies were excluded because were observational studies.

Aim
To determine consideration of periodontitis among Nigerian diabetologists. Key findings: Diabetes mortality and morbidity still high in Nigeria, Glycemic control poor in most patients. Nigerian diabetologists appear to be unaware of link between poor glycemic control and periodontitis.

Hypotheses resulting from synthesis
Most Nigerian studies on diabetes have centered on microangiopathy, mortality and determinants of glycemic control. None of the studies by Nigerian diabetologists have mentioned, considered or advocated periodontal evaluation as part of glycemic control protocol for Nigerian diabetics. Nigerian diabetologists appear unaware of the link between periodontitis and poor glycemic control. Current unacceptable mortality and morbidity of diabetes in Nigeria might be connected with this great omission. While the non-consideration of periodontitis appears to be the missing link for unexplained poor glycemic control among Nigerian diabetics, further studies in the form of surveying Nigerian diabetologists or interviews are needed to fully establish this missing link.

Inclusion Criteria Exclusion criteria
Nigerian Study Studies by other experts aside diabetologists

Reported in English language
Papers not limited to Nigeria

Human subjects Case reports
Glycemic control" / "control" of diabetes Reviews

Study carried out by diabetologists
Observational studies Interventional studies Based on the above, a total of 31 qualifying studies which met our criteria were included in the review. No other rigorous exclusion criteria were included. (Table2b, Figure 1)

Quality assessment
There's much confusion in literature and lack of consensus on whether quality assessment of publications should form an integral part of a metaethnography or not. We adopted and modified the list of criteria used by [7] to make the criteria relevant to our research question. Our results were expressed in percentages to give readers a clearer picture of the scenario.
Application of the modified quality criteria revealed that most of the Nigerian studies were strong on methodology, evidence-based conclusions and statement of study objectives. However, most studies were weak on adequate description and appropriateness of sampling methods. There was a rough balance among studies on adequate description of statistical tools and adequate description of study settings. However, based on the limitation that most study (26 of 31) assessments were based on abstracts, we followed the example of [7] and decided not to exclude any study on the basis of quality assessment scores alone (Table 3).

Reading the Studies and Determining Order of Constructs
As interpreted by Atkins and coworkers [7], this step should involve reading studies and determining the order of constructs. However, we found that most of our studies couldn't be categorized into these constructs without undue monotony. This conclusion emanates from the fact that virtually all the conclusions would fit into authors' interpretations of observations or results of interventions. This would make all our constructs 2nd order constructs which would result in undue monotony. We therefore decided to skip this step in our review.

Determining How the Studies are Related and Translating Studies into One Another
Since these two steps appear close in our interpretation, we decided to combine the two steps resulting in two tables. We decided to introduce colour-matching of the tables in order to make for easy reason and comparison of our initial synthesis with our reciprocal translations. Given the methods used by Atkins and coworkers [7], we arranged our studies into a chronological order for the purpose of comparison to translate one study into another, we decide to make use grouping and tabulation --tools recommended in developing a narrative synthesis as recommended by After this, we adopted the principle of reciprocal translation as explained by Atkins and coworkers [7] and recommended as a technique for exploring relationships by Jennie Popay and colleagues [8]. We adopted this approach for two main reasons. First, there's much confusion on the actual process of metaethnography and secondly, to avoid the easy trap of losing sacrificing the rich details of previous individual studies on the altar of some "higher interpretation" of the findings of previous studies. (Table  4&5)

Synthesizing Translations
The process for synthesizing translations is quite unclear as observed by [7]. For the purpose of our review, we decided that the narrative translation tool of tabulation combined with a modified form of reciprocal translation expressed in step 5 covered the requirements of the current step (6).

Expressing the Synthesis
From the foregoing so far, we can confidently express the argument/ hypotheses that 1. Most Nigerian studies on diabetes have centered on microangiopathy, mortality and determinants of glycemic control.     3. Nigerian diabetologists appear unaware of the link between periodontitis and poor glycemic control.

Current unacceptable mortality and morbidity of diabetes in
Nigeria might be connected with this great omission.
5. Periodontitis is the missing link for unexplained poor glycemic control among Nigerian diabetics.
As in other parts of the world, there are no such experts that we are aware of who are specifically in charge of diabetes and periodontal disease as a combined discipline. Nigeria is however endowed with many expert diabetologists who treat diabetes on one hand and extremely few periodontologists who treat periodontal disease. The focus of our paper is to encourage collaboration between these two groups of experts for the ultimate benefit of the Nigerian diabetic patient.

Conclusion
The message of this metaethnography combined with a bit of narrative synthesis is clear: The morbidity and mortality of type 2 diabetes mellitus in Nigeria remains unacceptably high. The 1978 observations of Oli [9] expressing concerns about "unexplained remissions," and more recent literature pointing to the associations between periodontitis and poor glycemic control - [1,2]. Han et al. [39] have shown that periodontitis predisposes to metabolic syndrome and diabetes while Lakschevitz et al. [40] presented evidence of the establishment of the adverse effect of periodontitis.
In a recent study, Colombo and coworkers demonstrated that Periodontal Disease Decreases Insulin Sensitivity and Insulin Signaling [41]. These are just the most recent among hundreds of studies. The evidence is overwhelming.
We have attempted to paint the obvious picture --the average Nigerian diabetologist appears UNAWARE of the effects of periodontitis on metabolic control in diabetes mellitus.
One case report is of special interest and was included in the discussion section because the authors had dismissed the association between diabetes and periodontitis based on a single case report and what they termed "personal observations." [42] So, is periodontitis the missing link in glycemic control attempts by Nigerian diabetologists? Only further studies in the form of surveys/ interviews of Nigerian diabetologists can answer this question in the affirmative.

Recommendations
We recommend the following; 1. Further studies in the form of surveys and /or interviews of Nigerian diabetologists to establish current knowledge and practice of this group of experts as it relates to ruling out periodontitis in glycemic control.
2. We recommendation (1) above confirm my fears, we recommend urgent steps to increase the awareness of the Nigerian diabetologists about the adverse effects of periodontitis on metabolic control.
3. The medical curriculum should include more modules in dentistry and urgent, sustained collaborative conferences and continuing education courses should be organized between Nigerian diabetologists and periodontologists.