METHODS: A total of 715 incident PD cases were ascertained in a cohort of 220 494 individuals from NeuroEPIC4PD, a prospective European population-based cohort study including 13 centres in eight countries. Smoking habits were recorded at recruitment. We analysed smoking status, duration, and intensity and exposure to passive smoking in relation to PD onset.
RESULTS: Former smokers had a 20% decreased risk and current smokers a halved risk of developing PD compared with never smokers. Strong dose-response relationships with smoking intensity and duration were found. Hazard ratios (HRs) for smoking <20 years were 0.84 [95% confidence interval (CI) 0.67-1.07], 20-29 years 0.73 (95% CI 0.56-0.96) and >30 years 0.54 (95% CI 0.43-0.36) compared with never smokers. The proportional hazard assumption was verified, showing no change of risk over time, arguing against a delaying effect. Reverse causality was disproved by the consistency of dose-response relationships among former and current smokers. The inverse association between passive smoking and PD, HR 0.70 (95% CI 0.49-0.99) ruled out the effect of unmeasured confounding.
CONCLUSIONS: These results are highly suggestive of a true causal link between smoking and PD, although it is not clear which is the chemical compound in cigarette smoking responsible for the biological effect.
METHODS: Screening periodontal examinations were carried out on all eligible Malay pregnant women in the second trimester of pregnancy attending two randomly selected community maternal and child health clinics in Kota Bharu, Kelantan. Patients with four or more sites with pocket depth 4 mm or higher, and clinical attachment loss 3 mm or higher at the same site with presence of bleeding on probing were diagnosed as having periodontitis in this study. Using this definition, systematic random sampling was utilized for selection of 250 subjects for each exposed and non-exposed group. Of 500 subjects enrolled in the study, 28 (5.6%) were either dropped or lost to follow-up. Of the remaining 472 subjects, 232 with periodontitis were in the exposed group and 240 with healthy periodontium were in the nonexposed group.
RESULTS: The incidence of LBW was 14.2% (95% CI: 9.70-18.75) in women with periodontitis, and 3.3% (95% CI: 1.05-5.62) in women without periodontitis. The relative risk of having LBW infants was 4.27 times higher for women with periodontitis compared with those without periodontitis (95% CI: 2.01-9.04). After adjustment for potential confounders using multiple logistic regression analysis, significant association was found between maternal periodontitis and LBW (OR = 3.84; 95% CI: 1.34-11.05).
CONCLUSION: The results of this study provide additional evidence that pregnant women with periodontitis are at a significantly higher risk of delivering LBW infants.
METHODS: A structured questionnaire was used to collect data on a child's current and previous illnesses, oral health behaviours, dietary habits, parental smoking behaviours and parents' dental history. The intraoral examination recorded dental caries (dmfs), enamel defects, gingival health, melanin pigmentation and soft tissue health. Stimulated saliva was collected. Total sIgA levels were quantified using indirect competitive ELISA with a SalimetricsTM kit.
RESULTS: The 44 children (aged 15-69 months) recruited were divided into two groups: ETS and non-ETS (control). There were 22 children in each: 16 who were exposed to ETS during and after gestation were identified as the ETSB subgroup. Participants exposed to ETS were more likely to have had upper respiratory tract and middle ear infections during the neonatal period and had higher mean dmft, mean dmfs, mean percent of surfaces with demarcated opacities and mean GI than the non-ETS participants. The children exposed to ETS before and after birth had the highest occurrence of enamel opacities showed a higher risk for dental caries even though more children in this group used the recommended fluoride toothpaste (1000 ppm fluoride). Mothers who smoked either never breastfed their children or breastfed their children for less than the recommended period of 6 months. Children exposed to ETS were shown to have higher mean total sIgA (μg/ml) than the children in the control group.
CONCLUSIONS: Associations between ETS exposure before and after gestation and oral health, including salivary changes in young children were shown in the present study. Dental health professionals should include a question about household smoking in children's dental histories, which would allow opportunities to discuss the impact of smoking on child oral health. Longitudinal oral health studies should include a history of maternal smoking during pregnancy and afterwards.