Food Insecurity and Metabolic Control Among U.S. Adults With Diabetes

OBJECTIVE We sought to determine whether food insecurity is associated with worse glycemic, cholesterol, and blood pressure control in adults with diabetes. RESEARCH DESIGN AND METHODS We conducted a cross-sectional analysis of data from participants of the 1999–2008 National Health and Nutrition Examination Survey. All adults with diabetes (type 1 or type 2) by self-report or diabetes medication use were included. Food insecurity was measured by the Adult Food Security Survey Module. The outcomes of interest were proportion of patients with HbA1c >9.0% (75 mmol/mol), LDL cholesterol >100 mg/dL, and systolic blood pressure >140 mmHg or diastolic blood pressure >90 mmHg. We used multivariable logistic regression for analysis. RESULTS Among the 2,557 adults with diabetes in our sample, a higher proportion of those with food insecurity (27.0 vs. 13.3%, P 9.0% (75 mmol/mol). After adjustment for age, sex, educational attainment, household income, insurance status and type, smoking status, BMI, duration of diabetes, diabetes medication use and type, and presence of a usual source of care, food insecurity remained significantly associated with poor glycemic control (odds ratio [OR] 1.53 [95% CI 1.07–2.19]). Food insecurity was also associated with poor LDL control before (68.8 vs. 49.8, P = 0.002) and after (1.86 [1.01–3.44]) adjustment. Food insecurity was not associated with blood pressure control. CONCLUSIONS Food insecurity is significantly associated with poor metabolic control in adults with diabetes. Interventions that address food security as well as clinical factors may be needed to successfully manage chronic disease in vulnerable adults

The Gly2019Ser mutation in LRRK2 is not fully penetrant in familial Parkinson's disease: the GenePD study

<p>Abstract</p> <p>Background</p> <p>We report age-dependent penetrance estimates for leucine-rich repeat kinase 2 (<it>LRRK2</it>)-related Parkinson's disease (PD) in a large sample of familial PD. The most frequently seen <it>LRRK2 </it>mutation, Gly2019Ser (G2019S), is associated with approximately 5 to 6% of familial PD cases and 1 to 2% of idiopathic cases, making it the most common known genetic cause of PD. Studies of the penetrance of <it>LRRK2 </it>mutations have produced a wide range of estimates, possibly due to differences in study design and recruitment, including in particular differences between samples of familial PD versus sporadic PD.</p> <p>Methods</p> <p>A sample, including 903 affected and 58 unaffected members from 509 families ascertained for having two or more PD-affected members, 126 randomly ascertained PD patients and 197 controls, was screened for five different <it>LRRK2 </it>mutations. Penetrance was estimated in families of <it>LRRK2 </it>carriers with consideration of the inherent bias towards increased penetrance in a familial sample.</p> <p>Results</p> <p>Thirty-one out of 509 families with multiple cases of PD (6.1%) were found to have 58 <it>LRRK2 </it>mutation carriers (6.4%). Twenty-nine of the 31 families had G2019S mutations while two had R1441C mutations. No mutations were identified among controls or unaffected relatives of PD cases. Nine PD-affected relatives of G2019S carriers did not carry the <it>LRRK2 </it>mutation themselves. At the maximum observed age range of 90 to 94 years, the unbiased estimated penetrance was 67% for G2019S families, compared with a baseline PD risk of 17% seen in the non-<it>LRRK2</it>-related PD families.</p> <p>Conclusion</p> <p>Lifetime penetrance of <it>LRRK2 </it>estimated in the unascertained relatives of multiplex PD families is greater than that reported in studies of sporadically ascertained <it>LRRK2 </it>cases, suggesting that inherited susceptibility factors may modify the penetrance of <it>LRRK2 </it>mutations. In addition, the presence of nine PD phenocopies in the <it>LRRK2 </it>families suggests that these susceptibility factors may also increase the risk of non-<it>LRRK2</it>-related PD. No differences in penetrance were found between men and women, suggesting that the factors that influence penetrance for <it>LRRK2 </it>carriers are independent of the factors which increase PD prevalence in men.</p

Obesity, race, and risk for death or functional decline among medicare beneficiaries: A cohort study

Background: The adverse effect of obesity on health outcomes may be lower in older and African American adults than in the general U.S. population. Objective: To examine and compare the relationship between obesity and all-cause mortality and functional decline among older U.S. adults. Design: Longitudinal cohort study. Setting: Secondary analysis of data from the 1994 to 2000 Medicare Current Beneficiary Surveys, linked to Medicare enrollment files through 22 April 2008. Participants: 20 975 community-dwelling participants in the 1994 to 2000 Medicare Current Beneficiary Surveys who were aged 65 years or older. Measurements: All-cause mortality through 22 April 2008; new or worsening disability in performing activities of daily living (ADLs) and instrumental activities of daily living (IADLs) in 2 years. Results: 37% of the study sample were overweight (body mass index [BMI] of 25 to <30 kg/m2), 18% were obese (BMI ≥30 kg/m2), 48% died during the 14-year follow-up, and 27% had ADL and 43% had IADL disability at baseline. Among those without severe disability at baseline, 17% developed new or worsening ADL disability and 26% developed new or worsening IADL disability within 2 years. After adjustment, adults with a BMI of 35 kg/m2 or greater were the only group above the normal BMI range who had a higher risk for mortality (hazard ratio, 1.49 [95% CI, 1.20 to 1.85] in men and 1.21 [CI, 1.06 to 1.39] in women, compared with the reference group [BMI of 22.0 to 24.9 kg/m2]; P for BMI–sex interaction = 0.003). In contrast, both overweight and obesity were associated with new or progressive ADL and IADL disability in a dose-dependent manner, particularly for white men and women. Significant interactions were detected between BMI and sex but not between BMI and race for any outcome, although risk estimates for ADL disability seemed attenuated in African American relative to white respondents. Limitation: This was an observational study, baseline data were self-reported, and the study had limited power to detect differences between white and African American respondents. Conclusion: Among older U.S. adults, obesity was not associated with mortality, except for those with at least moderately severe obesity. However, lower levels of obesity were associated with new or worsening disability within 2 years. Efforts to prevent disability in older adults should target those who are overweight or obese

Influence of neighboring reactive particles on diffusion-limited reactions

Competition between reactive species is commonplace in typical chemical reactions. Specifically the primary reaction between a substrate and its target enzyme may be altered when interactions with secondary species in the system are substantial. We explore this competition phenomenon for diffusion-limited reactions in the presence of neighboring particles through numerical solution of the diffusion equation. As a general model for globular proteins and small molecules, we consider spherical representations of the reactants and neighboring particles; these neighbors vary in local density, size, distribution, and relative distance from the primary target reaction, as well as their surface reactivity. Modulations of these model variables permit inquiry into the influence of excluded volume and competition on the primary reaction due to the presence of neighboring particles. We find that the surface reactivity effect is long-ranged and a strong determinant of reaction kinetics, whereas the excluded volume effect is relatively short-ranged and less influential in comparison. As a consequence, the effect of the excluded volume is only modestly dependent on the neighbor distribution and is approximately additive; this additivity permits a linear approximation to the many-body effect on the reaction kinetics. In contrast, the surface reactivity effect is non-additive, and thus it may require higher-order approximations to describe the reaction kinetics. Our model study has broad implications in the general understanding of competition and local crowding on diffusion-limited chemical reactions