Insulin resistance predicts the risk of gingival/periodontal inflammation

OBJECTIVES

Evaluate whether insulin resistance (IR) predicts the risk of oral inflammation, assessed as the number of sites with bleeding on probing (BOP) and number of teeth with probing pocket depths (PPD) ≥ 4 mm and BOP.

METHODS

Data on 870 overweight/obese diabetes free adults, aged 40-65 years from the San Juan Overweight Adults Longitudinal Study over a three-year period, was analyzed. Baseline IR, assessed using the Homeostasis Model Assessment of IR (HOMA-IR) index, was divided into tertiles. BOP was assessed at buccal and lingual sites, and PPD at six sites per tooth. Negative binomial regression was used to estimate the risk ratios (RRs) for oral inflammation adjusted for baseline age, gender, smoking status, alcohol intake, education, physical activity, waist circumference, mean plaque index, and baseline number of sites with BOP, or number of teeth with PPD≥4 mm and BOP. The potential impact of tertiles of serum TNF-α and adiponectin on the IR-oral inflammation association was also assessed in a subsample of 597 participants.

RESULTS

Participants in the highest HOMA-IR tertile at baseline had significantly higher numbers of sites with BOP [RR = 1.19, 95% confidence interval (CI): 1.03-1.36] and number of teeth with PPD ≥ 4 mm and BOP (RR = 1.39, 95% CI: 1.09-1.78) at follow-up, compared with individuals in the lower two HOMA-IR tertiles. Neither TNF-α nor adiponectin confounded the associations.

CONCLUSION

IR significantly predicts gingival/periodontal inflammation in this population.

Longitudinal association between adiposity and inter-arm blood pressure difference

This is the first longitudinal study evaluating whether adiposity is associated with inter-arm blood pressure difference. We evaluated 714 overweight/obese individuals aged 40-65 years over a 3-year follow-up. Systolic and diastolic blood pressures were measured in both arms simultaneously using an automated machine. Linear regression assessed the associations of body mass index, fat %, waist, neck, thigh, and arm circumferences (cm), with absolute inter-arm differences in systolic (IAS) and diastolic (IAD) blood pressure (mm Hg). Poisson regression was used for binary outcomes (IAS and IAD ≥ 10 mm Hg). All models were adjusted for age, gender, smoking, physical activity, and HOMA-IR. Adiposity measures were associated with increased IAS and IAD (β range: 0.09-0.20 and 0.09-0.30). Neck circumference showed the strongest association with IAS (β = 0.20, 95% CI: 0.03, 0.37) and IAD (β = 0.30, 95% CI: 0.12, 0.47); arm circumference showed a similar association with IAS, but lower with IAD. Highest quartiles of BMI, thigh, and arm showed significant associations with IAS (IRR: 2.21, 2.46 and 2.70). Highest quartiles of BMI, waist, neck, and arm circumferences were significantly associated with IAD (IRR: 2.38, 2.68, 4.50 and 2.24). If the associations are corroborated in other populations, adiposity may be an important modifiable risk factor for inter-arm blood pressure difference with a large potential public health impact.

Utility of point-of-care vs reference laboratory testing for the evaluation of glucose levels

AIMS

To assess the level of agreement between point-of-care and laboratory reference glucose values in defining glycaemic status.

METHODS

We analysed 1292 overweight/obese, non-institutionalized participants, aged 40-65 years, in the San Juan Overweight Adults Longitudinal Study. Fasting venous blood glucose was determined using a point-of-care Bayer Contour Blood Glucose Meter and by Vitros System 250 instrument (laboratory). American Diabetes Association thresholds were used to classify participants into normoglycaemia (< 5.6 mmol/l), prediabetes (5.6 to 6.9 mmol/l), or diabetes groups (≥ 7 mmol/l).

RESULTS

Bland-Altman plot analysis showed a slope of 0.04 (P=0.002) for the regression between the mean difference and the average of the two methods. The slopes were significantly different from zero among people with normoglycaemia (β=-0.57, P<0.001), and prediabetes (β=-0.75, P<0.001) but not among people with diabetes (β=-0.02, P=0.68). When the prediabetes and diabetes groups were merged into one group, the slope was 0.01, and the glucose values remained similar using the two methods (P=0.76).

CONCLUSION

Point-of-care blood glucose measurement may be useful to screen people with diabetes, and to assess glucose among individuals with diabetes where blood can be drawn, but laboratory tests are unavailable or untimely.

Longitudinal association between periodontitis and development of diabetes

BACKGROUND

Clinical trials have shown very modest short-term improvements in glycemic control among participants with diabetes after periodontitis treatment. Few longitudinal studies suggest that periodontitis may be related to prediabetes/diabetes risk.

METHODS

We evaluated 1206 diabetes free participants in the San Juan Overweight Adults Longitudinal Study (SOALS) and 941 with complete 3-year follow-up data were included. The National Health and Nutrition Examination Survey (NHANES) methods were used to assess periodontitis. Diabetes and prediabetes were classified using American Diabetes Association cutoffs for fasting and 2-hour post-load glucose and HbA1c. We used Poisson regression adjusting for baseline age, gender, smoking, education, family history of diabetes, physical activity, waist circumference, and alcohol intake.

RESULTS

Over the 3-year follow-up, 69 (7.3%) of the 941 individuals developed type 2 diabetes, and 142 (34.9%) of the 407 with normal glycemia at baseline developed prediabetes. In multivariable models, greater mean pocket depth and mean attachment loss at baseline were associated with lower risk of developing prediabetes/diabetes over the follow-up (IRR = 0.81; 95% CI: 0.67-0.99, and IRR = 0.86; 95% CI: 0.74-0.99, respectively). Increase in periodontal attachment loss from baseline to follow-up was associated with higher prediabetes/diabetes risk (multivariate IRR = 1.25; 95% CI: 1.09-1.42), and increase in pocket depth was associated with >20% fasting glucose increase (multivariate IRR = 1.43; 95% CI: 1.14-1.79). The inverse associations persisted after additionally adjusting for baseline income, sugar-sweetened beverages, number of teeth, oral hygiene, glycemia, or previous periodontal therapy.

CONCLUSIONS

There is no association between periodontitis and risk of prediabetes/diabetes in this longitudinal study.

Association between within-visit systolic blood pressure variability and development of pre-diabetes and diabetes among overweight/obese individuals

Short-term blood pressure variability is associated with pre-diabetes/diabetes cross-sectionally, but there are no longitudinal studies evaluating this association. The objective of this study is to evaluate the association between within-visit systolic and diastolic blood pressure variability and development of pre-diabetes/diabetes longitudinally. The study was conducted among eligible participants from the San Juan Overweight Adults Longitudinal Study (SOALS), who completed the three-year follow-up exam. Participants were Hispanics, 40–65 years of age, and free of diabetes at baseline. Within-visit systolic and diastolic blood pressure variability was defined as the maximum difference between three measures, taken a few minutes apart, of systolic and diastolic blood pressure respectively. Diabetes progression was defined as development of pre-diabetes/diabetes over the follow-up period. We computed multivariate incidence rate ratios adjusting for baseline age, gender, smoking, physical activity, waist circumference and hypertension status. Participants with systolic blood pressure variability ≥10 mm Hg compared to those with <10 mm Hg, showed higher progression to pre-diabetes/diabetes (RR=1.77, 95% CI: 1.30–2.42). The association persisted among never smokers. Diastolic blood pressure variability ≥ 10 mm Hg (compared to < 10 mm Hg) did not show an association with diabetes status progression (RR=1.20, 95% CI: 0.71–2.01). Additional adjustment of baseline glycemia, C- reactive protein, and lipids (reported dyslipidemia or baseline HDL or triglycerides) did not change the estimates. Systolic blood pressure variability may be a novel independent risk factor and an early predictor for diabetes, which can be easily incorporated into a single routine outpatient visit at none to minimal additional cost.

Over-the-counter mouthwash use and risk of pre-diabetes/diabetes

AIMS

Over-the-counter mouthwash comprises part of routine oral care for many; however, potential adverse effects of the long-term daily use have not been evaluated. Most mouthwash contain antibacterial ingredients, which could impact oral microbes critical for nitric oxide formation, and in turn predispose to metabolic disorders including diabetes. Our aim was to evaluate longitudinally the association between baseline over-the-counter mouthwash use and development of pre-diabetes/diabetes over a 3-year follow-up.

MATERIALS AND METHODS

The San Juan Overweight Adults Longitudinal Study (SOALS) recruited 1206 overweight/obese individuals, aged 40-65, and free of diabetes and major cardiovascular diseases; 945 with complete follow-up data were included in the analyses. We used Poisson regression models adjusting for baseline age, sex, smoking, physical activity, waist circumference, alcohol consumption, pre-hypertension/hypertension status; time between visits was included in the models as an offset.

RESULTS

Many participants (43%) used mouthwash at least once daily and 22% at least twice daily. Participants using mouthwash ≥ twice daily at baseline, had a significantly elevated risk of pre-diabetes/diabetes compared to less frequent users (multivariate IRR = 1.55, 95% CI: 1.21-1.99), or non-users of mouthwash (multivariate IRR = 1.49; 95% CI: 1.13-1.95). The effect estimates were similar after adding income, education, oral hygiene, oral conditions, sleep breathing disorders, diet (processed meat, fruit, and vegetable intake), medications, HOMA-IR, fasting glucose, 2hr post load glucose or CRP to the multivariate models. Both associations were also significant among never-smokers and obese individuals. Mouthwash use lower than twice daily showed no association, suggesting a threshold effect at twice or more daily.

CONCLUSIONS

Frequent regular use of over-the-counter mouthwash was associated with increased risk of developing pre-diabetes/diabetes in this population.

Relationship between tooth loss and peripheral arterial disease among women

AIM

We assessed the longitudinal association between tooth loss and peripheral arterial disease (PAD) within the Nurses' Health Study.

MATERIALS AND METHODS

After excluding participants with prior cardiovascular diseases, 277 of 79,663 women were confirmed as PAD cases during 16 years of follow-up. Number of teeth and recent tooth loss were reported initially in 1992. Subsequent tooth loss was recorded in 1996 and in 2000. We evaluated the associations of baseline number of teeth and recent tooth loss with risk of PAD, adjusting for age, smoking, diabetes, hypertension, high cholesterol, aspirin use, family history of myocardial infarction, BMI, alcohol consumption, physical activity, postmenopausal hormone use, and use of vitamin E, vitamin D, multivitamin and calcium.

RESULTS

Incident tooth loss during follow-up was significantly associated with higher hazard of PAD (HR = 1.31 95% CI: 1.00-1.71). However, the association appeared inverse among never smokers. There was no dose-response relationship between baseline number of teeth and PAD.

CONCLUSIONS

Tooth loss showed a modest association with PAD, but no dose-response relationship was observed.

Comparing glucose and hemoglobin A1c diagnostic tests among a high metabolic risk Hispanic population

BACKGROUND

Compare glycated hemoglobin (HbA1c ) diagnostic tests for prediabetes and diabetes with plasma glucose criteria and compare the metabolic profiles of people classified by HbA1c versus by glucose levels.

METHODS

Participants were recruited for the San Juan Overweight Adults Longitudinal Study. The participants were primarily Hispanic (98%), without previously diagnosed diabetes, and aged 40 to 65 years. Participants classified as normal glycemic, prediabetes, or diabetes on the basis of baseline HbA1c and plasma glucose criteria were compared with respect to baseline cardiometabolic factors.

RESULTS

The 1342 participants had a mean age of 50.5 ± 6.8 years and 28% were men. Thirty-one percent were diagnosed with prediabetes by plasma glucose criteria and 53.4% by HbA1c , and 8.1% were diagnosed with diabetes by plasma glucose criteria and 6.3% by HbA1c ; overall concordance rate was 55.1%. The area under the receiver operating characteristic curve of HbA1c compared to plasma glucose criteria was 0.62 for impaired glucose and 0.76 for diabetes. A worse cardiometabolic profile was seen within subgroups that met HbA1c and plasma glucose criteria for diabetes or prediabetes. Those diagnosed with prediabetes by plasma glucose criteria had significantly higher systolic blood pressure and higher homeostatic model assessment than those diagnosed using HbA1c . Participants diagnosed with diabetes by plasma glucose criteria had lower body mass index, smaller waist circumference, and lower insulinogenic and disposition indices, but higher homeostatic model assessment of insulin resistance, than those diagnosed by HbA1c .

CONCLUSIONS

Low concordance was seen between HbA1c and glucose measurements. The HbA1c is not a good test for prediabetes but shows reasonable validity for diabetes in this high-risk predominantly female Hispanic population. People classified by HbA1c , plasma glucose criteria, or both show different metabolic profiles; a combined test may be ideal.

Lipid-lowering agents use and systemic and oral inflammation in overweight or obese adult Puerto Ricans: the San Juan Overweight Adults Longitudinal Study (SOALS)

The effects of lipid-lowering agents (LLA) on reducing systemic and oral inflammation have not been evaluated.

OBJECTIVE

To assess the association of LLA use with high-sensitivity C-reactive protein (hs-CRP) and oral inflammation.

DESIGN

Cross-sectional analysis using baseline data from 1300 overweight/obese participants aged 40-65 years, recruited for the ongoing San Juan Overweight Adults Longitudinal Study. Serum hs-CRP was measured by ELISA, gingival/periodontal inflammation was evaluated as bleeding upon probing (BOP), and LLA was self-reported. Separate logistic models were performed for systemic and oral inflammation.

RESULTS

In all, 24% participants reported history of dyslipidaemia, of which, 50.3% self-reported LLA use. Sixty percent of the participants had elevated hs-CRP (>3 mg/dl) and 50% had high BOP (defined as at or above the median: 21%). After adjusting for age, gender, smoking, HDL-C, physical activity, diabetes, blood pressure medications, and percent body fat composition, LLA users had significantly lower odds of elevated hs-CRP compared to LLA non-users (OR = 0.58; 95% CI: 0.39-0.85). After adjusting for age, gender, smoking status, educational level, mean plaque index and percent body fat, LLA users had significantly lower odds of high BOP compared to LLA non-users (OR = 0.62; 95% CI: 0.42-0.91).

CONCLUSIONS

Lipid-lowering agents may reduce both systemic and oral inflammatory responses.

Associations between measures of central adiposity and periodontitis among older adults

OBJECTIVE

To evaluate the association between measures of adiposity and periodontitis among older Puerto Rican adults.

METHODS

A cross-sectional study was conducted among 147 representative adults ≥70 years living in the San Juan metropolitan area. Height, weight, waist circumference (WC), and hip circumference were measured by trained personnel. Periodontal probing depth and attachment loss (AL) were measured by calibrated examiners. Periodontitis was classified according to the Center for Disease Control/American Academy of Periodontology (CDC-AAP) definitions and using tertiles of mean AL and percent of sites with AL ≥3 mm. Multivariable polytomous logistic regression models adjusted for age, gender, smoking, education, diabetes status, physical activity, and total fruit and vegetable intake were used to model associations between WC, waist-to-hip ratio (WHR), and periodontitis.

RESULTS

High WC (men: ≥102 cm versus <102 cm, women: ≥88 cm versus <88 cm) compared with normal showed nonsignificant associations with severe (OR = 2.56, 95% CI: 0.76-8.67), moderate periodontitis (OR = 1.53, 95% CI: 0.65-3.60), and upper tertile of mean AL (OR = 2.28, 95% CI: 0.83-6.23). Elevated WHR versus normal (men: ≥0.95 versus <0.95, women: ≥0.88 versus <0.88) was associated with moderate periodontitis (OR = 2.36, 95% CI: 1.01-5.52) and showed a borderline significant association with the upper tertile of mean AL (OR = 2.52, 95% CI: 0.96-6.63, P = 0.06).

CONCLUSIONS

Central adiposity was associated with a greater risk of periodontitis in this population of older adults, although analyses were underpowered. These results hold important public health implications given the high prevalence of adiposity and periodontitis among older adults.