Discovering medical conditions associated with periodontitis using linked electronic health records

Abstract

Aim: To use linked electronic medical and dental records to discover associations between periodontitis and medical conditions independent of a priori hypotheses.

Materials and methods: This case-control study included 2475 patients who underwent dental treatment at the College of Dental Medicine at Columbia University and medical treatment at NewYork-Presbyterian Hospital. Our cases are patients who received periodontal treatment and our controls are patients who received dental maintenance but no periodontal treatment. Chi-square analysis was performed for medical treatment codes and logistic regression was used to adjust for confounders.

Results: Our method replicated several important periodontitis associations in a largely Hispanic population, including diabetes mellitus type I (OR = 1.6, 95% CI 1.30-1.99, p < 0.001) and type II (OR = 1.4, 95% CI 1.22-1.67, p < 0.001), hypertension (OR = 1.2, 95% CI 1.10-1.37, p < 0.001), hypercholesterolaemia (OR = 1.2, 95% CI 1.07-1.38, p = 0.004), hyperlipidaemia (OR = 1.2, 95% CI 1.06-1.43, p = 0.008) and conditions pertaining to pregnancy and childbirth (OR = 2.9, 95% CI: 1.32-7.21, p = 0.014). We also found a previously unreported association with benign prostatic hyperplasia (OR = 1.5, 95% CI 1.05-2.10, p = 0.026) after adjusting for age, gender, ethnicity, hypertension, diabetes, obesity, lipid and circulatory system conditions, alcohol and tobacco abuse.

Conclusions: This study contributes a high-throughput method for associating periodontitis with systemic diseases using linked electronic records.

Fig 1

Associations between periodontitis and other medical conditions. Medical conditions associated with periodontitis are shown above. ICD-9 codes above the red line are associations that pass the Bonferroni significance threshold while codes above the blue line are associations supported by the Benjamini-Hochberg correction method. Shortened disease names are given next to each significantly associated ICD-9 code.

Fig 2

ICD-9 codes with low frequency achieve significance after aggregation. Orange nodes represent periodontitis patients and blue nodes represent control patients. Unique ICD-9 codes may be too infrequent (<5 patients each) to achieve significance at the individual code level (see a) but at the category level (see b) the frequency is sufficient (>5 patients) to determine the presence of an association.