Relationship between serum uric acid and cerebral white matter lesions in the elderly.

BACKGROUND AND AIMS: Recent evidence suggests that hyperuricemia might increase the risk of cardiovascular disease. Cardiovascular risk factors are well recognized to be associated with cerebral white matter lesion (WML). We hypothesized that hyperuricemia is related to higher grade of WML in both men and women. METHODS AND RESULTS: A total of 108 men and 123 women were enrolled from those who signed up for the annual Health Examination for the Elderly Program in Taipei from 2006 to 2008. Information in interview data, clinical and laboratory examinations were collected. Hyperuricemia was defined by uric acid ≥458.0 µmol/L in men and ≥392.6 µmol/L in women. Two types of WML including periventricular hyper-intensity (PVH) and deep white matter hyper-intensity (DWMH), ascertained by cranial magnetic resonance imaging, were graded. Association between hyperuricemia and high grade WML was evaluated by using multiple logistic regression analysis. The prevalences of hyperuricemia were 13.9% and 17.9% for men and women, respectively. The prevalences of moderate-to-severe PVH among men and women were 16.7% and 7.3%; while the prevalences of moderate-to-severe DWMH for men and women were 19.4% and 11.4%, respectively. Hyperuricemia was related to moderate-to-severe DWMH in men, after controlling for age, education years, smoking, alcohol consumption, metabolic Z score, silent infarct, and the use of anti-hypertensives, lipid-lowering and anti-diabetic agents, the association remained significant. The relationship was not evident among women. We did not find an association between hyperuricemia and PVH. CONCLUSIONS: Hyperuricemia was positively associated with high grade DWMH in older men, but not in women.

Effects of obesity, physical activity, and cardiorespiratory fitness on blood pressure, inflammation, and insulin resistance in the National Health and Nutrition Survey 1999-2002.

BACKGROUND AND AIMS: This study was designed to elucidate the effects of obesity, self-reported physical activity and cardiorespiratory fitness on blood pressure, inflammation, and insulin resistance. METHODS AND RESULTS: Data from 950 Caucasian subjects ranging in age from 19 to 49 years from the National Health and Nutrition Survey (NHANES), 1999-2002, were included to construct a population-based observational study. Cardiorespiratory fitness (VO(2) max) was predicted from a submaximal exercise stress test. Self-reported physical activity was measured by metabolic equivalent score transformed from a questionnaire. A structural equation model (SEM) was developed to examine the relationship between obesity, cardiorespiratory fitness, self-reported physical activity, and hypertension, inflammation, and insulin resistance. The model showed that obesity was positively linked to hypertension (B=0.50, P<0.001) and C-reactive protein (CRP; B=0.15, p<0.05), which in turn led to insulin resistance (B=0.44, P<0.05). Increased cardiorespiratory fitness was negatively associated with CRP (Γ=-0.23, P<0.01), but not correlated to hypertension after adjustment for potential confounding factors. No significant association was found between self-reported physical activity and hypertension, insulin resistance, and CRP. CONCLUSION: Obesity contributes to the development of hypertension, inflammation, and insulin resistance. Improved cardiorespiratory fitness might lead to clinical and biochemical improvement in insulin resistance by reducing the inflammatory state.

Factors associated with foveoschisis and foveal detachment without macular hole in high myopia.

PURPOSE: To investigate the associated factors of foveoschisis and foveal detachment without macular hole in highly myopic eyes. METHODS: A cross-sectional study of 124 eyes of 68 highly myopic patients was performed. The patients underwent complete ocular examination, fundus photography, and optical coherence tomography (OCT). RESULTS: Of the 124 eyes, 10 (8%, 10/124) had foveoschisis or foveal detachment without a macular hole on OCT examination. On the basis of univariate analysis, six variables were associated with the pathologic changes, including age over 40 years (P=0.018), spherical equivalent over 10 D (P=0.042), axial length over 31 mm (P=0.001), macular chorioretinal atrophy (P=0.00003), posterior staphyloma (P=0.0003), and vitreoretinal interface factors, including epiretinal membrane, posterior vitreoschisis, and vitreomacular traction (P=0.00002). In the multivariate analysis, three factors were independently associated with foveoschisis and foveal detachment without macular hole in high myopia: axial length, macular chorioretinal atrophy, and vitreoretinal interface factors. CONCLUSIONS: Foveoschisis and foveal detachment without macular hole are sight-threatening disorders in highly myopic eyes. Axial length, macular chorioretinal atrophy, and vitreoretinal interface factors were independently associated with these pathological conditions. Thus, both intraocular and outer ocular wall factors play important roles and merit further study.

Assessment of macular retinal thickness and volume in normal eyes and highly myopic eyes with third-generation optical coherence tomography.

PURPOSE: To compare the macular retinal thickness and macular volume between subjects with high myopia and non-myopia. METHODS: This prospective nonrandomized, comparative study recruited healthy subjects with high myopia subjects, defined as a spherical equivalence (SE) over -6 dioptres (D) or AXL>or=26.5 mm and the best corrected visual acuity better than 20/25, and subjects with non-myopia, defined as an with SE between 1.5D and -1.5 D and the BCVA better than 20/25. Optical coherence tomography was performed in each eye. RESULTS: Eighty high myopic eyes and 40 non-myopic eyes were included. The mean age of the high myopic group and non-myopia group was 29.6 and 27.5 years old, respectively. The mean refraction was -9.27 D in the high myopia group and -0.22 D in the non-myopia group. The high myopia group had significantly greater mean retinal thickness in the foveola and fovea 1 mm area than the non-myopia group (166 vs149 microm, P<0.0001, 199 vs188 microm, P=0.0063, respectively). However, the mean retinal thickness in the inner and outer macular area (superior, nasal, inferior, or temporal) of the high myopia group was significantly less than in the non-myopia group. In addition, the high myopia group had significantly smaller macular volume than the non-myopia group (P<0.0001). CONCLUSION: This study demonstrated that the retinal thickness in individuals with high myopia is thicker in the foveola and fovea, but thinner in the inner and the outer macular region. The retina of individuals with high myopia had smaller macular volume than those with non-myopia.

Microalbuminuria is a negative correlate for cognitive function in older adults with peripheral arterial disease: results from the U.S. National Health and Nutrition Examination Survey 1999-2002.

OBJECTIVES: Microalbuminuria (MA) has been increasingly identified as a marker of cardiovascular risk. Although poor cognitive function has been implicated as a sequelae of increased cardiovascular burden, little is known about the association between MA and cognitive function. DESIGN: Population-based cross-sectional study. SETTINGS: National Health and Nutrition Examination Survey 1999-2002 in the USA. SUBJECTS: 2049 noninstitutionalized adults (>/=60 years) with nonmissing values in cognitive test, urinary albumin-to-creatinine ratio (UACR) and ankle-brachial blood pressure index (ABPI) was analysed. Participants with UACR >300 microg mg(-1) were excluded. MAIN OUTCOME MEASURES: The UACR, in the unit of microg mg(-1), was calculated by dividing the urinary albumin value by the urinary creatinine concentration. MA was defined as UACR between 30 and 300 microg mg(-1). Cognitive function was measured by a 2-min Digit Symbol Substitution Test (DSST). Peripheral artery disease (PAD) was defined as an ABPI <0.9 in either leg. RESULTS: Overall speaking, MA was inversely associated with DSST score after controlling for age, sex, race, body mass index and educational level (regression coefficient = -2.8, P = 0.002). There was an effect modification of PAD on the association between MA and the DSST score. Amongst participants with PAD, the DSST score for those with MA was lower than those without MA (beta = -6.3, P = 0.003) after multivariate adjustment. Moreover, participants with PAD in the highest quartile of UACR had significantly lower DSST score compared to those in the lowest quartile (beta = -8.7, P = 0.001). There was no association between MA and cognitive function amongst participants without PAD. We observed an additive effect of MA and PAD on DSST score. Participants with both MA and PAD had a lower mean DSST score compared to those without both conditions (beta = -6.2, P = 0.003). CONCLUSIONS: The presence of MA or a higher level of urinary albumin excretion was inversely associated with cognitive function in participants with PAD.

Levels of homocysteine are inversely associated with cardiovascular fitness in women, but not in men: data from the National Health and Nutrition Examination Survey 1999-2002.

OBJECTIVES: Cardiovascular fitness represents the ability of active skeletal muscle to utilize oxygen during aerobic exercise. Elevated homocysteine, causing tissue injury by such mechanisms as oxidative stress, endothelial damage, and protein homocysteinylation, is associated with increased risk of cardiovascular disease, dementia and osteoporotic fracture. However, the association between elevated homocysteine and cardiovascular fitness has not been reported. DESIGN: Population-based cross-sectional study. SETTING: National Health and Nutrition Examination Survey from 1999 to 2002 in the USA. SUBJECTS: A total of 1444 noninstitutionalized adults aged 20--49 years with reliable measures of cardiovascular fitness and non-missing values in homocysteine. Main outcome measures. Cardiovascular fitness, estimated maximal oxygen uptake or VO(2)max (mL kg(-1) min(-1)), was obtained by a submaximal exercise test. Levels of homocysteine were measured by the Abbott homocysteine assay, a fully automated fluorescence polarization immunoassay method and were natural-log-transformed due to right skewness. RESULTS. After adjustment for age, race and body mass index, there was a 0.70 mL kg(-1) min(-1) decrease (P=0.033) in the estimated VO(2)max for each standard deviation (SD) increase in the natural-log-transformed homocysteine level for women. Additional adjustment of hypertension, diabetes, smoking status, alcohol intake, use of lipid-lowering agents, physical activity, self-report health condition, as well as levels of folate, vitamin B(12), creatinine, C-reactive protein, total cholesterol and haemoglobin seemed to influence the association. In the fully adjusted model, we observed a 1.18 mL kg(-1) min(-1) decrease (P=0.003) in the estimated VO(2)max for each SD increase in the natural-log-transformed homocysteine level in women. There was no association between cardiovascular fitness and homocysteine levels in men. CONCLUSION. High homocysteine levels were inversely associated with cardiovascular fitness in women, but not in men. The results suggest that homocysteine levels are important indicators of exercise tolerance amongst women and may be useful in targeting female individuals requiring endurance intervention to prevent loss of cardiovascular fitness and function.