Periodontitis and gestational diabetes

Background + Aims

• Gestational diabetes mellitus (GDM) is a carbohydrate intolerance which begins during pregnancy, with Indian women at significantly higher risk (approximately 11-fold) compared to Caucasians.
• The incidence of GDM in India was reported at 16.55% in 2004.
• GDM is associated with increased maternal and foetal complications, including pre-term birth (born <37 weeks of gestation), macrosomia (newborn with excessively high birth weight), shoulder dystocia (difficulty delivering the newborn due to the shoulder becoming lodged), pre-eclampsia (high blood pressure which may result in complications to mother and newborn if untreated), and birth injury (physical damage/ trauma sustained by the newborn during childbirth).
• Periodontal disease, a prevalent chronic condition, is linked to systemic inflammation and adverse pregnancy outcomes.
• Studies indicate that severe periodontitis increases diabetes complications and may contribute to the development of hyperglycaemia.
• Research has examined the association between periodontal disease and GDM, indicating that chronic inflammation from periodontitis could contribute to the onset of GDM.
• This study aims to explore the relationship between periodontal disease, GDM, and pregnancy outcomes in an Indian cohort.

Materials + Methods

• The study was a prospective cohort conducted at Lok Nayak Hospital and Maulana Azad Medical College, New Delhi, from October 2014 to March 2016.
• The study aimed to recruit 370 primigravidae women with periodontitis (accounting for a 25% follow-up loss), aged 20–35 years, with single live intrauterine pregnancies at 12–14 weeks of gestation.
  • With an approximate periodontitis prevalence of 57%, 650 primigravidae women were required
• Eligible participants had ≥ 20 teeth and were excluded if they had pre-existing diabetes, chronic conditions, or recent periodontal treatment.
• Periodontal examinations were conducted by a calibrated periodontist blinded to (unaware of) the patients’ GDM status. They recorded the following parameters:
  • Probing pocket depth (PPD)
  • Clinical attachment loss (CAL)
  • Bleeding on probing (BOP)
• Periodontitis was defined as ≥4 teeth with sites showing PPD ≥4 mm and CAL ≥3 mm, along with BOP.
• Participants underwent a 2-hour 75g oral glucose tolerance test (OGTT) at their first visit, with GDM diagnosed if 2-hour plasma glucose levels were ≥140 mg/dl based on The Diabetes in Pregnancy Study Group (DIPSI) guidelines. Women with normal glucose levels were retested at 24–28 weeks.
• Those diagnosed with GDM received standard hospital care, and all were followed until delivery.
• The adverse pregnancy outcomes assessed were:
  • Pre-eclampsia – blood pressure ≥140/90 mmHg after 20 weeks of gestation with 24-hour urine protein ≥300 mg in previously normotensive women.
  • Pre-term labour – delivery before 37 weeks of gestation
  • Placental abruption – premature separation of the placenta from the uterus before delivery
  • Foetal growth restriction – foetal weight below the 10th percentile for gestational age (confirmed through ultrasound and abnormal Doppler findings)
  • Polyhydramnios – excessive amniotic fluid (deepest vertical pool exceeded 8 cm or the amniotic fluid index was above the 95th percentile for gestational age)
  • Obstructed labour
  • Low birthweight – defined as birthweight <2.5 kg)
  • Stillbirth
  • Shoulder dystocia – the baby’s shoulders fail to deliver after the head requiring additional obstetric maneuvers
  • Hypoglycaemia in newborns – diagnosed when plasma glucose levels were <30 mg/dl
  • Birth trauma
  • Congenital abnormalities
  • Nursery admission
• Statistical analyses aimed to identify risk factors for GDM and adverse outcomes, with a significance level set at p < 0.05.

Results

• The study analysed 584 participants, of which 57 (9.8%) were diagnosed with GDM:
  • GDM detected at 12- 14 weeks: 21 women
  • GDM detected at 24 – 28 weeks: 36 women
• The 584 participants were classified based on dental health into:
  • Healthy gums (n=252)
  • Gingivitis (n=184)
  • Periodontitis (n=148)
  • With periodontal diseases (gingivitis/ periodontitis) (n = 332 / 56.8%)
• The incidence of GDM varied significantly across groups, being highest among women with periodontitis (19.6%) compared to 4.4% in healthy women.
• Univariate analysis revealed that age, anaemia status, and socioeconomic status (SES) were associated with GDM occurrence.
• Multivariate Cox-regression analysis confirmed that periodontal disease was a significant risk factor for GDM, with an adjusted hazard ratio (HR) of 2.85 (95% CI: 1.47–5.53, p=0.002)
• Pre-eclampsia occurred in 48 (8.2%) of participants with the highest incidence in women with periodontitis (20.3%) (p = .0001).

Limitations