BACKGROUND: During the last few years, risk assessment has become one of the main topics of periodontal research. Therefore, the aim of this study was to determine whether a predisposition to metabolic disorders such as diabetes mellitus (in the absence of diagnosed diabetic disease) or hyperlipidemia may be risk indicators for periodontitis.

METHODS: One hundred patients ranging in age from 40 to 70 years were examined. The patients were classified as having impaired glucose tolerance (IGT) but no manifest diabetes (56 patients), hyperlipidemia (17 patients, HL), or normal metabolic status (27 control patients). Probing depth (PD), attachment level (AL), plaque index (PI), and gingival bleeding on probing (BOP) were recorded. Serum antibody titers (SAT) to A. actinomycetemcomitans (A.a.), P. intermedia (P.i.), and P. gingivalis (P.g.) were determined by enzyme-linked immunosorbent assay (ELISA). Pooled subgingival plaque samples were analyzed using indirect immunofluorescence to detect the same organisms. In addition, respiratory burst activity of peripheral polymorphonuclear leukocytes (PMN) was evaluated by chemiluminescence (CL).

RESULTS: No significant differences were observed between the IGT group and normal controls in the following parameters: 1) percentage of sites exhibiting BOP; 2) mean PI; 3) mean PD and AL; 4) percentage of periodontal microorganisms; and 5) increased SAT. The IGT probands exhibited a significantly higher mean serum level of triglycerides, as well as higher formyl-methionyl-leucyl-phenylalanine (FMLP)-stimulated PMN chemiluminescence than the control group. Patients with hyperlipidemia (HL) showed a significantly higher number of sextants with increased PD (73.4%) than the control group (50.6%). Similar results were obtained when comparing the percentage of all sites with increased PD (HL = 16.7%, control 12.3%). The mean FMLP-stimulated CL in patients with hyperlipidemia was significantly higher than the control group. When looking at all patients, there was a small but statistically significant correlation between PD and lipid levels. In addition, a significant correlation was observed between lipid serum levels and the FMLP-stimulated chemiluminescence.

CONCLUSIONS: These findings suggest that abnormal glucose tolerance, which is a predisposing factor for diabetes mellitus, does not appear to be a risk indicator for periodontal disease. On the other hand, impaired lipid metabolism does seem to be a risk indicator for periodontitis.