The Subgingival Microbiome Relationship to Periodontal Disease in Older Women.

Understanding of the oral microbiome in relation to periodontal disease in older adults is limited. The composition and diversity of the subgingival microflora and their oligotypes in health and levels of periodontal disease were investigated in this study on older postmenopausal women. The 16S rRNA gene was sequenced using the Illumina MiSeq platform in 1,206 women aged 53 to 81 y. Presence and severity of periodontal disease were defined by Centers for Disease Control and Prevention/American Academy of Periodontology criteria. Composition of the microbiome was determined by 16S rRNA amplicon sequencing and the abundance of taxa described by the centered log2-ratio (CLR) transformed operational taxonomic unit (OTU) values. Differences according to periodontal disease status were determined by analysis of variance with Bonferroni correction. Bacteria oligotypes associated with periodontal disease and health were determined by minimum entropy decomposition and their functions estimated in silico using PICRUSt. Prevalence of none/mild, moderate, and severe periodontal disease was 25.1%, 58.3%, and 16.6%, respectively. Alpha diversity of the microbiome differed significantly across the 3 periodontal disease categories. ß-Diversity differed between no/mild and severe periodontal disease, although considerable overlap was noted. Of the 267 bacterial species identified at ≥0.02% abundance, 56 (20.9%) differed significantly in abundance according to periodontal disease status. Significant linear correlations for pocket depth and clinical attachment level with bacterial amounts were observed for several taxa. Of the taxa differing in abundance according to periodontal disease status, 53% had multiple oligotypes appearing to differ between none/mild and severe periodontal disease. Among older women, taxonomic differences in subgingival microbiome composition and diversity were observed in relation to clinical periodontal disease measures. Potential differences in bacterial subspecies (oligotypes) and their function were also identified in periodontal disease compared with health.

Vitamin D Status and Prevalent Early Age-Related Macular Degeneration in African Americans and Caucasians: The Atherosclerosis Risk in Communities (ARIC) Study.

OBJECTIVES: Vitamin D status has been hypothesized to protect against development of early age-related macular degeneration (AMD) via its anti-inflammatory properties and its possible beneficial influence on blood pressure control. We investigated the association between vitamin D status and prevalent early AMD in a community-based cohort. DESIGN: This was a cross-sectional study. SETTING: This was a secondary data analysis of already existing data from the Atherosclerosis Risk in Communities Study (ARIC) cohort collected from 1990 to 1995. PARTICIPANTS: There were 9,734 (7,779 Caucasians, 1,955 African American) ARIC participants (aged 46 to 70 at visit 2 [1990-1992]) with 25(OH)D data available at visit 2, AMD assessment at visit 3 (1993-1995), and complete covariate data. MEASUREMENTS: Vitamin D status was assessed with serum 25-hydroxyvitamin D (25(OH)D) concentrations from bloods drawn at visit 2. Prevalent, early AMD (n=511) was assessed at visit 3 (1993-95) with nonmydriatic retinal photographs of one randomly chosen eye. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for early AMD by categories of 25(OH)D in nmol/L (deficient <30, inadequate 30-<50, and two categories of adequate status: 50-<75 and ≥75). Linear trend was estimated using continuous 25(OH)D concentrations. ORs were adjusted for age, race, and smoking status. We further adjusted for hypertension status to examine if vitamin D status influenced early AMD via its effects on blood pressure. Exploratory analyses of effect modification by age, sex, race and high risk genotypes [Y402H complement factor H (CFH) rs1061170 and the A69S age-related maculopathy susceptibility 2 (ARMS2) rs10490924 polymorphisms] were conducted. RESULTS: The prevalence of early AMD was 5%, and 5% of participants were vitamin D deficient. The adjusted OR (95% CIs) for early AMD among those with adequate (≥75 nmol/L) compared to deficient (<30 nmol/L) vitamin D status was 0.94 (0.59-1.50), p-trend=0.86. Further adjustment for hypertension status did not influence results (OR [95% CI]=0.95 [0.59-1.52], p-trend=0.84). Results did not vary significantly by age, race, sex, early AMD subtype (soft drusen or retinal pigment epithelium depigmentation), or ARMS2 genotype. Results did not vary significantly by CFH genotype in African Americans. The p for multiplicative interaction between 25(OH)D and CFH genotype was 0.06 in Caucasians, but OR [95% CIs] for AMD by vitamin D status were similar in each CFH genotype and not statistically significant. CONCLUSIONS: Vitamin D status was not associated with early AMD in this cohort sample.

The relationship between body mass index and per cent body fat in the severely obese.

BACKGROUND: International standards define clinical obesity according to body mass index (BMI) without reference to age and gender. Recent studies among adults in the normal to mildly obese BMI ranges have shown that the relationship between BMI and per cent body fat (% fat) differs by age and gender. The extent to which age and gender affect the relationship between BMI and % fat among more severely obese individuals is less known. AIM: The aim was to examine the age-gender association between measured BMI and % fat from a large cohort of adults, including a large number of severely obese subjects (1862 with a BMI > or = 35 kg/m(2)). METHODS: BMI was computed from measured height and weight, and % fat was estimated from bioelectrical impedance in 3068 adults. Two impedance equations, the Sun equation and the Heath equation (specific to severe obesity), were used to calculate % fat. RESULTS: Average age for 991 men and 2077 women was 46 +/- 15 vs. 44 +/- 14 years respectively (p = 0.0003). The average BMI was 36 +/- 9 kg/m(2) for men and 39 +/- 10 kg/m(2) for women (p < 0.0001), with a combined gender BMI range of 19-74 kg/m(2). Using the Sun equation, average % fat was 31 +/- 8 vs. 46 +/- 8% (p < 0.0001) for all men and women respectively. With the Sun equation, age-adjusted Spearman correlations between all BMI and % fat values were r = 0.80 and r = 0.83 for men and women, respectively, but only 0.60 (n = 479) and 0.61 (n = 1383) in severely obese participants (BMI > or = 35 kg/m(2)). Using the Heath equation, only for participants with BMI > or = 35 kg/m(2), the age-adjusted Spearman correlations improved to r = 0.82 (n = 479) and r = 0.70 (n = 1383) for men and women respectively. Finally, by combining the Sun equation for subjects with BMI < 35 kg/m(2) and the Heath equation for those with BMI > or = 35 kg/m(2), correlations improved to 0.89 for men and 0.87 for women. Using these combined equations, the relationship between BMI and % fat was best fit as a linear function for men and curvilinear function (both p < 0.001) for women across the range of BMI. The % fat was approximately 10% higher for any BMI value among women vs. men even among the severely obese (p < 0.0001). CONCLUSIONS: These data that include a large cohort of severely obese individuals demonstrated a linear association between BMI and % fat for men and a curvilinear association between BMI and % fat for women when Sun and Heath equations were combined. Assuming disease risk is driven by adiposity, this study suggests a need to further explore the appropriateness of gender-specific BMI cutpoints for clinical risk assessment due to the marked difference in the BMI-per cent fat relation observed in men and women across the entire range of BMI.

Obesity, macrophage migration inhibitory factor, and weight loss.

OBJECTIVE: Elevated macrophage migration inhibitory factor (MIF) has been implicated as a causal mechanism in a number of disease conditions including cardiovascular disease (CVD), diabetes, and cancer. Excess body fat is associated with an increased risk of numerous health conditions including CVD, diabetes, and cancer. To our knowledge, the association between MIF and obesity status and the effect of weight loss on serum MIF concentrations have not been reported. In this study, we examined the effects of participation in a behavior-based weight loss program on MIF concentrations in obese individuals. SUBJECTS: Study participants were 71 men and women enrolled in The Cooper Institute Weight Management Program. Participants were predominantly female (68%, n=48), middle-aged (46.5+/-9.8 y), and severely obese (BMI=43.0+/-8.6). METHOD: Plasma MIF concentrations and other standard risk factors were measured before and after participation in a diet and physical activity based weight management program. RESULTS: The mean follow-up was 8.5+/-3.0 months with an average weight loss of 14.4 kg (P<0.001). The majority of clinical risk factors significantly improved at follow-up. Median levels of plasma MIF concentration were significantly lower at follow-up (median [IQR]; 5.1[3.6-10.3]) compared to baseline (8.4 [4.3-48.8]; P=0.0005). The percentage of participants with plasma MIF concentration > or =19.5 mg/nl (highest tertile at baseline) decreased from 33.8 to 5.6% (P<0.001). Further, elevated baseline plasma MIF concentration was associated with markers of beta-cell dysfunction and reductions in MIF were associated with improvements in beta-cell function. CONCLUSIONS: Circulating MIF concentrations are elevated in obese but otherwise healthy individuals; however, this elevation in MIF is not uniform across individuals. In obese individuals with elevated circulating MIF concentrations, participation in physical activity and a dietary-focused weight management program resulted in substantial reduction in MIF.

Quantifying energy expenditure and physical activity in the context of dose response.

PURPOSE: Methods for assessing physical activity (PA) and energy expenditure (EE) were reviewed to identify potential limitations to evaluating and interpreting dose-response relationships between PA and health-related outcomes and to suggest future research directions in this area. METHODS: Literature describing PA and EE assessment methodology was reviewed according to the reported validity, reliability, and feasibility of the measurement in epidemiologic studies. A summary of this review is presented for techniques applicable to studying PA or EE among free-living individuals. RESULTS: Several methods with varying degrees of precision and feasibility have been used to assess PA and EE in free-living populations. Lack of a gold standard field measure of PA may explain some of the variability in precision among these methods. The most accurate field measure of EE appears to be doubly labeled water; however, this approach has limited feasibility in terms of cost and use in studies of total EE only. Electronic motion sensors and physiologic measures related with EE are limited in their ability to discriminate specific types of PA and by inconvenient measurement procedures. Self-reported PA records and surveys are low-cost, relatively unobtrusive methods of assessing PA and EE in field settings and vary in terms of their format, mode of administration, and degree of detailing habitual PA levels. Disparity in the metric used to quantify PA and EE exists within the current literature, which limits the interpretation and comparison of observed dose-response relationships. CONCLUSIONS: Efforts to develop equated methods of assessing PA and EE in free-living populations are needed before a systematic evaluation and interpretation of dose-response characteristics between PA and specific health-related parameters can be undertaken.

Physical activity, physical fitness, and Framingham 10-year risk score: the cross-cultural activity participation study.

PURPOSE: Although physical activity and physical fitness are inversely and causally associated with coronary heart disease (CHD) morbidity and mortality, available equations for estimating CHD risk do not include scores for activity or fitness. Therefore, this study evaluated the association of physical fitness and moderate-intensity physical activity with the 10-year Framingham CHD risk estimate. METHODS: Cross-sectional analyses were performed on data from 137 healthy middle-aged women (53.9 +/- 9.9 yr; 28.3 +/- 6.0 kg/m2). Health histories, body composition, blood pressure, and blood samples were obtained from a clinical examination. Levels of moderate (3-6 METS) intensity physical activity, expressed as MET-minutes/day of energy expenditure, were derived from multiple 24-hour physical activity records. Physical fitness was quantified as duration of a symptom-limited maximal treadmill exercise test. RESULTS: After adjustment for race, body mass index (BMI), and hormone replacement status, a graded reduction in the Framingham risk score was observed across low (5.8%), moderate (4.0%), and high (3.6%) fitness levels (P for trend = 0.009). Women in both the moderate and high fitness categories had a lower (P < 0.01) risk score compared with their low fit counterparts. Significant differences in risk were not seen among low (3.9%), moderate (4.9%), and high (4.4%) physical activity groups. The lack of association between the risk score by physical activity may have been due to the homogeneity of activity levels among participants. Our findings reinforce existing data that show enhanced levels of fitness are associated with lower risk for CHD.

Cardiorespiratory fitness and coronary heart disease risk factors: the LDS Hospital Fitness Institute cohort.

BACKGROUND: Cardiorespiratory fitness is favorably associated with most modifiable coronary heart disease (CHD) risk factors. Findings are limited, however, by few data for women, persons with existing CHD, and low-risk populations. In the present study, we described cross-sectional associations between cardiorespiratory fitness and CHD risk factors in a large cohort of middle-aged men and women, of whom the majority were LDS Church members (Mormons), with and without existing CHD. METHODS AND RESULTS: Comprehensive health examinations were performed on 3232 men (age 45.9+/-10.8 years) and 1128 women (age 43.8+/-12.8 years) between 1975 and 1997. Maximal treadmill exercise testing was used to categorize those with (12% of the men and 10% of the women) and those without CHD into age- and sex-specific cardiorespiratory fitness quintiles. After adjustments for age, body fat, smoking status, and family history of CHD, favorable associations were observed between fitness and most CHD risk factors among men and women, regardless of CHD status. CONCLUSIONS: These data indicate that enhanced levels of cardiorespiratory fitness may confer resistance to elevations in CHD risk factors even in a low-risk sample of middle-aged men and women. Furthermore, these findings reinforce current public health recommendations that advocate increased national levels of physical activity and cardiorespiratory fitness for primary and secondary CHD prevention.