In our last blog we looked at one review that assess the association between periodontitis and obesity, two of the commonest chronic disorders in the world. The aim of this review of prospective longitudinal studies was to assess the effects of weight gain on the incidence of periodontitis in adults.
Searches were conducted in the Medline, Embase, Web of Knowledge and Scopus databases. Prospective observational studies assessing the association between weight gain and incidence of periodontitis in adults aged 18 or older were considered. A clear description of nutritional status (Body Mass Index; Waist Circumference) as well as the case definition of periodontitis was required. Case-control, cross-sectional studies, longitudinal retrospective studies, animal studies, in-vitro studies, letters to the editor and reviews were excluded. Two reviewers selected studies and abstracted data. The Newcastle–Ottawa scale for cohort studies was used to assess the quality of included studies. The overall quality of evidence was estimated according to the GRADE guideline.
5 studies involving a total of 42,198 patients were included.
All studies were conducted in high-income countries; Finland, Japan, USA.
Meta-analysis considering the effects of weight gain on the incidence of periodontitis showed that compared with those who stayed at normal weight those who became
- overweight had an increased risk of periodontitis; RR= 1.13; (95% CI; 1.06–1.20).
- obese had an increased risk of periodontitis; RR= 1.33; (95% CI; 1.21–1.47).
The overall quality of evidence was considered to be moderate using the GRADE approach.
The authors concluded:
A clear positive association between weight gain and new cases of periodontitis was found. However, these results are originated from limited evidence. Thus, more studies with longitudinal prospective design are needed.
Earlier this week we looked at another recently published review by Keller et al assessing the link between weight gain and periodontal disease (Dental Elf-14th Sep-2015). Both of these reviews have included prospective studies. While this current review has used a broader search because of different inclusion criteria only 5 of the cohort studies included in the Keller review were included here. The Keller review decided against a meta-analysis because of concerns regarding the measurements and cu-off points for periodontal disease, and Nascimento et al raise some of these issues in in the discussion. They also highlight that the pooled analysis were performed on probing depth rather than the preferred measure of clinical attachment loss. The small number of studies available for the review precluded a formal assessment of publication bias so this should be considered when assessing the findings.
Nascimento GG, Leite FR, Do LG, Peres KG, Correa MB, Demarco FF, Peres MA. Is weight gain associated with the incidence of periodontitis? A systematic review and meta-analysis. J Clin Periodontol. 2015 Jun;42(6):495-505. doi: 10.1111/jcpe.12417. Epub 2015 Jun 2. PubMed PMID: 25952821.
Keller A, Rohde JF, Raymond K, Heitmann BL. Association between periodontal disease and overweight and obesity: a systematic review. J Periodontol. 2015 Jun;86(6):766-76. doi: 10.1902/jop.2015.140589. Epub 2015 Feb 12. PubMed PMID: 25672656.