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PubMed2005

Characteristics of a population of COPD patients identified from a population-based study. Focus on previous diagnosis and never smokers.

OBJECTIVE: To identify factors associated with diagnosis and health-related quality of life (HRQL) impairment in chronic obstructive pulmonary disease (COPD) patients from a population-based epidemiological study. DESIGN AND PARTICIPANTS: This was an epidemiologic, multicenter, population-based study. Three hundred and sixty-three individuals diagnosed with COPD from a randomly general population sample of 4035 individuals aged 40-69 were included in the analyses. INTERVENTIONS: Forced spirometry was performed on eligible subjects, and the European Commission for Steel and Coal (ECSC) and the St. George's Respiratory Questionnaires (SGRQ) were completed. Logistic regression models were constructed to identify variables associated with the previous diagnosis of COPD and with COPD in never smokers. A multiple linear regression model attempted to identify variables influencing HRQL impairment. RESULTS: Only 79 (21.7%) COPD patients had been previously diagnosed. Disease severity based on FEV(1), worse SGRQ score, previous respiratory disease, as well as the presence of wheezing were significantly associated with previous diagnosis. Being a woman, older than 55, with previous respiratory disease and without expectoration or wheezing characterized COPD in never smokers. A worse HRQL was associated with chronic symptoms, especially dyspnea; and with older age, cardiac comorbidity and impairment in lung function. CONCLUSIONS: Diagnosis of COPD in the community is more likely in patients with worse lung function and HRQL, and wheezing is the symptom most strongly associated with a diagnosis of COPD. Women older than 55, with previous respiratory diseases, without respiratory symptoms and mild airflow obstruction constitute the majority of individuals with COPD who have never smoked. Chronic respiratory symptoms are strongly associated with impairment in HRQL.

Adult↗

PubMed1995

Predictors of outcome in patients who underwent cataract surgery.

PURPOSE: To identify preoperative patient characteristics associated with a lack of improvement on one or more measures 4 months after cataract surgery. METHODS: The authors collected preoperative and 4-month postoperative information on 552 patients undergoing first-eye cataract surgery from the practices of 72 ophthalmologists in three cities. The principal outcomes assessed were (1) Snellen visual acuity, (2) a cataract-related symptom score (possible range: 0, 0 of 6 symptoms present or bothersome, to 18, all 6 symptoms very bothersome), and (3) a measure of functional impairment in patients with cataract--the VF-14 score (possible range: 0, inability to perform any of the applicable activities, to 100, no difficulty performing any of the applicable activities). Multiple logistic regression was used to assess the association between preoperative patient characteristics and failure to improve on one or more outcome measures. Multiple linear regression was used to estimate the adjusted rate of lack of improvement in one or more outcome measures for one group of patients compared with another. RESULTS: Although 91 patients (16.5%) failed to improve on one or more of the outcome measures assessed, only 2 (0.4%) failed to improve on all three measures. The 91 patients who did not improve on at least one measure were approximately one sixth as likely to be satisfied with their vision postoperatively as the 461 patients who improved on all three outcome measures. Preoperative age of 75 years of age or older, VF-14 score of 90 or higher, cataract symptom score of 3 or lower, and ocular comorbidity (glaucoma, diabetic retinopathy, or age-related macular degeneration) were associated independently with increased likelihood of not improving on one or more measure (odds ratio: 3.57, 2.10, 3.29, and 2.16, respectively). The mean adjusted rate of failure to improve on at least one of the outcome measures ranged from 20.5% to 26.5% for patients with these preoperative characteristics compared with 8.8% to 13.8% for those patients without them. The preoperative level of Snellen visual acuity was not associated with the likelihood of not improving on one or more of the outcomes assessed. CONCLUSIONS: The authors conclude that specific preoperative characteristics (age, comorbidity, cataract symptom score, and VF-14 score) are independent predictors of patient outcome after cataract surgery.

Aged↗

PubMed1988

The prediction of body composition in poultry by estimation in vivo of total body water with tritiated water and deuterium oxide.

1. Birds (n 169) which varied in age, live weight, nutritional history, physiological state and genotype were slaughtered and analysed for total body water. Before slaughter, birds were injected with the water isotopes tritiated water (TOH) or deuterium oxide (D2O), or both, to determine TOH space or D2O space, or both, as estimates of total body water in vivo. 2. At the mean total body water of all birds determined by desiccation, of 1096.4 (SD 424.1) g, TOH space and D2O space overestimated total body water by 10.4 and 8.5% respectively. The difference between the isotopes was significant (P less than 0.05). 3. Based on recovery of isotope it was postulated that the main reason for the observed overestimation of total body water in vivo was incomplete recovery of isotope due to the vacuum sublimation technique. The mean recovery (%) of added isotope to whole blood after vacuum sublimation was 93.0 (SD 2.6) and 92.4 (SD 5.5) of the theoretical concentrations of TOH and D2O respectively. 4. Nevertheless, accurate prediction of total body water was obtained from regression equations which included live weight and isotope-dilution space. Values required logarithmic (base 10) transformation before derivation of linear and multiple linear regression equations, and the precision of prediction was determined by the residual standard deviation (RSD). 5. Total body water could be predicted with nearly equal accuracy from live weight or isotope-dilution space (RSD 0.025 and 0.020 respectively). Prediction of carcass protein was more accurate from live weight (RSD 0.033) than from TOH space (RSD 0.036), and inclusion of both variables resulted in only a marginal decrease in RSD to 0.031. 6. The prediction of carcass fat and energy was markedly improved by the inclusion of isotope-dilution space in conjunction with live weight compared with live weight alone. 7. The relations show the developmental nature of body composition of domestic fowl given diets adequate in nutrients. The prediction equations demonstrate the precision possible for studies in which estimates of body composition in poultry are required without slaughter.

Animals↗

PubMed2004

Effect of environmental exposure to cadmium on pregnancy outcome and fetal growth: a study on healthy pregnant women in China.

The objective of the present study was to evaluate the potential effect of environmental exposure to cadmium on pregnancy outcome and fetal growth. Normal pregnant women were selected from Da-ye city of Hubei province, a cadmium-polluted area, from November 2002 through January 2003. Whole blood of pregnant women, cord blood, and placenta were collected and cadmium levels were determined by inductively coupled plasma emission mass spectroscopy. Incidence rate of preterm labor (gestational age < or = 37 weeks) and neonatal asphyxia, neonatal birth height, and birth weight were compared between lower and higher cadmium exposure level groups. Whole blood cadmium of 44 mothers ranged from 0.80 to 25.20 microg/L. Cadmium concentration in maternal blood was significantly higher than that in cord blood (t = 11.44, P < 0.01). Placenta cadmium ranged from 0.084 to 3.97 microg/g dry weight. After adjustment for maternal age, history of gestation, abortion and lactation, Logistic regression analysis showed that there was no significant association between cadmium exposure levels and pregnancy outcome (premature labor or neonatal asphyxia). Multiple linear regression analysis showed that, cord blood cadmium level, but not maternal blood cadmium and placenta cadmium, was significantly negatively associated with neonatal birth height (t= -2.33, P < 0.05). Compared with lower cord blood cadmium level (< or = 0.40 microg/L), higher level of cord blood cadmium (>0.40 microg/L) was associated with 2.24cm decrease in neonatal birth height. There was no significant association between cadmium exposure and birth weight. It was concluded that environmental exposure to cadmium significantly lower neonatal birth height.

Adult↗

PubMed2006

Admission physiology criteria after injury on the battlefield predict medical resource utilization and patient mortality.

BACKGROUND: Medical resources and resource allocation including operating room and blood utilization are of prime importance in the modern combat environment. We hypothesized that easily measurable admission physiologic criteria and injury site as well as injury severity calculated after diagnostic evaluation or surgical intervention, would be strongly correlated with resource utilization and in theater mortality outcomes. METHODS: We retrospectively reviewed the Joint Theater Trauma Registry for all battlefield casualties presenting to surgical component facilities during Operation Iraqi Freedom from January to July 2004. Data were collected from the composite population of 1,127 battlefield casualty patients with respect to demographics, mechanism, presentation physiology (blood pressure, heart rate, temperature), base deficit, admission hematocrit, Glasgow Coma Score (GCS), Injury Severity Score (ISS), operating room utilization, blood transfusion, and mortality. Univariate and multivariate analyses were conducted to determine the degree to which admission physiology and injury severity correlated with blood utilization, necessity for operation, and acute mortality. RESULTS: Univariate analysis demonstrated a significant (p < 0.05) association between hypothermia (T < 34 degrees C) and the subsequent requirement for operation and mortality. In addition, the outcome variable total blood product utilization was significantly correlated with base deficit (r = 0.61), admission hematocrit (r = 0.51), temperature (r = 0.47), and ISS (r = 0.54). Using multiple logistic regression techniques, blood pressure, GCS, and ISS together demonstrated a significant association (p < 0.05) with mortality (area under ROC curve = 95%). Multiple linear regression established that blood pressure, heart rate, temperature, hematocrit, and ISS had a collective significant effect (p < 0.05) on total blood product utilization explaining 67% of the variance in this outcome variable. CONCLUSION: Admission physiology and injury characteristics demonstrate a strong capacity to predict resource utilization in the contemporary battlefield environment. In the future, such predictive yield could potentially have significant implications for triage and medical logistics in the resource constrained environment of war and potentially in mass casualty and disaster incidents in the civilian trauma setting which will likely have mechanistic similarity with war related injury.

Blood Pressure↗

PubMed1990

Nasal and oral flow-volume loops in normal subjects and patients with obstructive sleep apnea.

Because flow-volume loops (FVLs) are clinically useful in evaluating upper airway (UA) obstruction and the fact that patency of the nasopharyngeal ventilatory pathway is important to the prevention of obstructive sleep apnea (OSA), the present study examined the role of nasal compared with oral FVLs in evaluating patients with OSA. Fourteen obese male patients 56 +/- 3 yr of age with a mean apnea plus hypopnea index (AHI) of 51 +/- 9/h were studied along with 14 nonobese, healthy, age- and sex-matched control subjects whose mean AHI was 6 +/- 1/h. Nasal and oral FVLs obtained in the normal subjects indicated the nose behaved like a variable resistor, with flow limitation during inspiration but not during expiration. In the patient group, flow limitation was observed during expiration as well as inspiration indicating nondistensibility of the nasopharyngeal ventilatory pathway in the patients compared to the control subjects. A change in body position from upright to supine in the OSA group was associated with small reductions in expiratory but not inspiratory flow rates. The area under the nasal supine flow-volume loop (FVLANaSup) was found to be highly correlated with awake resting PaO2 (r = 0.80) and PaCO2 (r = -0.83) in the patient group. In addition, multiple linear regression analysis revealed that PaO2 and the area under the nasal FVLs independently contributed to the prediction of AHI with a multiple R of 0.89. These results suggest that limitations to ventilation via the nasopharynx may significantly influence both gas exchange and the frequency of sleep-disordered breathing in patients with OSA.(ABSTRACT TRUNCATED AT 250 WORDS)

Airway Resistance↗

PubMed2005

The force required to induce hemivein pulsation is associated with the site of maximum field loss in glaucoma.

PURPOSE: To determine the factors associated with central retinal vein pulsation changes in glaucoma and identify any hemiretinal vein pulsation changes and their association with sectoral visual field loss. METHODS: One hundred twenty-six patients with glaucoma and 40 normal subjects had automated perimetry, blood pressure, and intraocular pressure measured. A hemifield sensitivity loss was calculated from the upper and lower halves of each field. Those without spontaneous venous pulsation on the optic disc had an ophthalmodynamometer applied, to measure the minimum ophthalmodynamometric force (ODF) necessary to induce venous pulsation. When ODF was restricted to the hemiveins, the force needed to induce pulsation in each hemivein was measured. RESULTS: Eighty-three patients with glaucoma had no spontaneous venous pulsation. The minimum ODF was strongly correlated with mean deviation (Spearman rank r = -0.475, P < 0.0001). Mixed linear regression analysis showed that mean deviation (P < 0.0001) and pulse blood pressure (P < 0.0001) were significantly associated with minimum ODF. There was a strong association between differences in hemifield sensitivity loss and in hemivein ODF (rank r = 0.369, P < 0.0001, n = 80). Multiple linear regression modeling demonstrated that lower hemivein ODF was independently associated with upper field loss (P = 0.003) and upper hemivein ODF with lower field loss (P < 0.0001). CONCLUSIONS: These venous pulsation findings in glaucoma are independent of blood pressure. The hemifield and hemivein association suggests that the major hemivein change is adjacent to the site of major disc damage.

Aged↗

PubMed1985

Aerobic capacity, obesity, and atherosclerotic risk factors in male adolescents.

Correlations between aerobic capacity, obesity, and atherosclerotic risk factors were evaluated in adolescents with low-to-moderate levels of physical fitness. Subjects with higher levels of fitness had a more favorable risk profile with decreased body mass index, lower systolic and diastolic blood pressure and plasma triglyceride levels, and higher plasma high-density lipoprotein-cholesterol levels. Simple linear regression analysis revealed an association between body mass index and blood pressure, plasma triglyceride and plasma high-density lipoprotein-cholesterol. The level of aerobic fitness as determined by exercise duration was also associated with the same atherosclerotic risk factors. However, multiple linear regression analysis demonstrated that body mass index provided the largest explanation, by those variables examined, of the interindividual variance in blood pressure, plasma triglyceride, and high-density lipoprotein-cholesterol. Aerobic fitness contributed only minimally to the variation in these risk factors. These findings suggest that if aerobic conditioning is used to modify atherosclerotic risk factors, it should be accompanied by a reduction in weight in adolescents with low-to-moderate levels of physical fitness.

Adolescent↗

PubMed1992

A rapid, sensitive, and easy-to-perform solid phase insulin radioimmunoassay.

Accurate measurement of basal insulin release in perifusion, perfusion and low-density beta-cell preparations has been difficult with present assays. A simple, competitive, equilibrium, 15-hour insulin assay using 125I-insulin with microtiter plate immobilized antibody, has been developed. This method, a Solid-phase-RadioImmunoAssay (SPRIA), is very sensitive and has a broad useful range (1 - 64 microU/ml). For a test series of 4 standard curves, interassay variation between controls of 1, 4, 16, and 64 microU/ml was +/- 5.2% (SEM) and intra-assay variation over the range of standards between 0.5 to 64 microU/ml was 5.1% (SEM). Nonspecific binding was not significantly different from empty borosilicate culture tubes; 4.0 +/- 0.4 and 3.5 +/- 0.5 counts/minute (mean +/- SEM; n = 54), respectively. This SPRIA can be used with existing gamma-counters, while reducing the radioactive and glass waste presently produced by RIA (test-tubes can be reused). The radioactivity of unused test-tubes was compared against test-tubes used for greater than 10 assays, values were 3.5 +/- 0.5 and 4.4 +/- 0.6 counts/minute mean +/- SEM; n = 54), respectively. Results of an oral glucose tolerance test (oGTT) performed on four male Wistar Furth rats showed a close correlation between SPRIA and RIA insulin values (linear regression, r2 = 0.990). This SPRIA measured plasma insulin levels from a human oGTT with a variation of less than or equal to 3.7% (SEM) between sample triplicates. Standard curves from three commonly measured insulin isoforms (human, rat and porcine) showed a high correlation (multiple linear regression, r2 = 0.998, n = 5 standard curves). In order to determine SPRIA's ability to measure acid extracts, insulin recovery from 2N acetic acid was compared against insulin recovery from Dulbecco's Modified Eagles medium (DME). The insulin recovery from 2N acetic acid was greater than 90% of that achieved with DME. In conclusion, an easy-to-perform assay which is ideal for the rapid quantification of insulin from isolated islets of Langerhans, isolated beta-cells, acetic acid extracts or plasma with greater sensitivity, and less waste than the conventional RIA has been developed.

Adult↗

PubMed1996

Circulating TNF-alpha and leptin levels in offspring of NIDDM patients do not correlate to individual insulin sensitivity.

Obesity plays a central role in the development of skeletal muscle insulin resistance. The molecular mechanism causing skeletal muscle insulin resistance in obese people is still poorly understood. It has been speculated that circulating factors derived from adipose tissue impair insulin signalling in the skeletal muscle cell. TNF-alpha and leptin, which are overproduced in fat tissue of obese insulin resistant animal models and in obese humans, might mediate such an inhibitory effect on insulin signalling in skeletal muscle. The aim of the present study was to evaluate whether circulating TNF-alpha and leptin correlates to the individual skeletal muscle insulin sensitivity in individuals with different degrees of obesity and insulin resistance. We measured circulating TNF-alpha and leptin values in non diabetic offsprings of NIDDM patients. 36 German and 47 Finnish subjects participated in the study. The GDR of each participant was determined by the euglycemic hyperinsulinemic clamp technique, a range between 1.37 to 14.01 mg/kg LBM x min was observed. Percent of desirable body weight (PDW) covered also a wide range (87.58% to 197.06%). Although linear regression analysis suggested a dependence between TNF-alpha and GDR (Germany group: r = -0.37, p < 0.05, Finnish group: r = -0.32, p < 0.05) and a dependence between TNF and PDW (German group: r = 0.46, p < 0.05, Finnish group: r = 0.38, p < 0.05), in multiple linear regression analysis only the correlation with PDW was significant. Leptin levels were measured from 29 German and 36 Finnish subjects and a strong association was found between leptin and PDW (German group: r = 0.55, p < 0.05, Finnish group: r = 0.73, p < 0.05). In contrast, leptin levels did not correlate with GDR and TNF-alpha. In summary, even though, in a few insulin resistant subjects, higher circulating TNF-alpha or leptin levels with the individual insulin sensitivity can be demonstrated, the data suggest that the circulating pool of TNF-alpha and leptin in blood is unlikely to be a major contributing factor for obesity induced insulin resistance in the vast majority of individuals at high risk to develop NIDDM.

Adult↗

PubMed2003

Positive correlation of skeletal muscle UCP3 mRNA levels with overweight in male, but not in female, rats.

The objective of this study was to investigate the sex-dependent regulation of skeletal muscle uncoupling protein (UCP)3 mRNA expression in response to overweight and its relationship with serum levels of free fatty acids, leptin, and insulin. Two obesity models were used: rats made obese by feeding them with a cafeteria diet for 14 wk, and postcafeteria overweight rats fed a chow diet for 10 wk after consuming the cafeteria diet for 14 wk. The effects of 24-h fasting were studied in postcafeteria rats and their age-matched controls. The cafeteria rats ate a high-fat diet and attained an excess body weight that was higher in females (+59%) than in males (+39%). A trend to higher induction of abdominal muscle UCP3 mRNA in male rats than in females after cafeteria diet was apparent (+116% increase vs. +26% increase). Postcafeteria male but not female rats still showed the tendency to have increased UCP3 mRNA levels relative to their age-matched controls. A linear regression analysis showed a significant positive correlation of the UCP3 mRNA levels with overweight and with serum levels of leptin and insulin in males, but not in females, and no correlation with serum free fatty acid levels. A subsequent correlation analysis and a multiple linear regression analysis showed that overweight was the only parameter actually related to UCP3 mRNA levels in males. Fasting-induced upregulation of muscle UCP3 mRNA levels was higher in males (5- to 7-fold) than in females (3- to 4-fold). Our results point to the existence of sex-associated differences in the control of muscle UCP3 expression in response to overweight and fasting, with an impaired induction in female rats under both conditions. The correlation of abdominal muscle UCP3 mRNA expression with overweight in males could be related to their relative resistance to gain weight after chronic overeating of a cafeteria diet, by the purported role of UCP3 in the regulation of lipid utilization.

Animal Feed↗

PubMed2002

Predictive mapping of air pollution involving sparse spatial observations.

A limited number of sample points greatly reduces the availability of appropriate spatial interpolation methods. This is a common problem when one attempts to accurately predict air pollution levels across a metropolitan area. Using ground-level ozone concentrations in the Tucson, Arizona, region as an example, this paper discusses the above problem and its solution, which involves the use of linear regression. A large range of temporal variability is used to compensate for sparse spatial observations (i.e. few ozone monitors). Gridded estimates of emissions of ozone precursor chemicals, which are developed, stored, and manipulated within a geographic information system, are the core predictor variables in multiple linear regression models. Cross-validation of the pooled models reveals an overall R2 of 0.90 and approximately 7% error. Composite ozone maps predict that the highest ozone concentrations occur in a monitor-less area on the eastern edge of Tucson. The maps also reveal the need for ozone monitors in industrialized areas and in rural, forested areas.

Air Pollutants↗

PubMed2006

Improving effectiveness and evaluation techniques of stormwater best management practices.

This paper presents results of an extensive field monitoring program of a proprietary stormwater treatment technology called the Stormvault. Analysis of 39 storms indicates that the system effectively and consistently reduced total suspended solids (TSS) average event mean concentration (EMC) from 70.6+/-17.0 mg/L to 41.2+/-3.7 mg/L. Results were comparable to or better than conventional best management practices (BMPs). Multiple linear regression indicated that interactions between site and storm characteristics significantly effect effluent EMC. The simple regression equation can be used to directly compare multiple systems for a given site and/or between watersheds.

Rain↗

PubMed2004

An ecological study of caries experience, school performance and material deprivation in 5-year-old state primary school children.

AIM: To investigate whether measures of school performance and socioeconomic circumstances could be used as indicators of caries experience in 5-year-old Wandsworth state primary schoolchildren. DESIGN: An ecological study using aggregated caries data collected in the British Association for the Study of Community Dentistry (BASCD) Oral Health Survey of 5-year-old children (2001), Jarman scores generated from national census data and matched by school postcodes (1991), school performance results in English, mathematics and Linguistic Awareness of Reading Readiness test (LARR; literacy) and free school meals recipient data from the Local Education Authority, Research and Evaluation Unit (2001). SETTING: State primary schools in the London borough of Wandsworth, UK. SUBJECTS: All 55 Wandsworth state primary schools including 1968 5-year-old pupils. OUTCOME MEASURE: The school mean dmft score. RESULTS: Simple linear regression analysis demonstrated that school mean dmft was statistically significantly associated with all five explanatory variables: English (P = 0.001), mathematics (P = 0.002), LARR (P < 0.001), the percentage of children receiving free school meals (P < 0.001) and the school address Jarman score (P = 0.02). Stepwise multiple linear regression identified the LARR score and the percentage of children receiving free school meals as the strongest indicators of school mean dmft score explaining 41% of the variation in school mean dmft score. CONCLUSION: Early school performance results in English, mathematics and LARR, the percentage of children receiving free school meals and school address Jarman scores were good indicators of school mean dmft scores in 5-year-old children in the Wandsworth state primary schools.

Child, Preschool↗

PubMed1998

Pharmacokinetics of sparfloxacin in the serum and vitreous humor of rabbits: physicochemical properties that regulate penetration of quinolone antimicrobials.

We have used a recently described animal model to characterize the ocular pharmacokinetics of sparfloxacin in vitreous humor of uninfected albino rabbits following systemic administration and direct intraocular injection. The relationships of lipophilicity, protein binding, and molecular weight to the penetration and elimination of sparfloxacin were compared to those of ciprofloxacin, fleroxacin, and ofloxacin. To determine whether elimination was active, elimination rates following direct injection with and without probenecid or heat-killed bacteria were compared. Sparfloxacin concentrations were measured in the serum and vitreous humor by a biological assay. Protein binding and lipophilicity were determined, respectively, by ultrafiltration and oil-water partitioning. Pharmacokinetic parameters were characterized with RSTRIP, an iterative, nonlinear, weighted, least-squares-regression program. The relationship between each independent variable and mean quinolone concentration or elimination rate in the vitreous humor was determined by multiple linear regression. The mean concentration of sparfloxacin in the vitreous humor was 59.4% +/- 12.2% of that in serum. Penetration of sparfloxacin, ciprofloxacin, fleroxacin, and ofloxacin into, and elimination from, the vitreous humor correlated with lipophilicity (r2 > 0.999). The linear-regression equation describing this relationship was not improved by including the inverse of the square root of the molecular weight and/or the degree of protein binding. Elimination rates for each quinolone were decreased by the intraocular administration of probenecid. Heat-killed Staphylococcus epidermidis decreased the rate of elimination of fleroxacin. Penetration of sparfloxacin into the noninflamed vitreous humor was greater than that of any quinolone previously examined. There was an excellent correlation between lipophilicity and vitreous entry or elimination for sparfloxacin as well as ciprofloxacin, fleroxacin, and ofloxacin. There are two modes of quinolone translocation into and out of the vitreous humor: diffusion into the eye and both diffusion and carrier-mediated elimination out of the vitreous humor.

Animals↗

PubMed2002

Plasma homocysteine levels and atherosclerosis in Japan: epidemiological study by use of carotid ultrasonography.

BACKGROUND AND PURPOSE: We examined whether hyperhomocysteinemia is an independent risk factor for increased carotid artery intimal-medial wall thickness (IMT) in a large, randomly selected community in Japan where the dietary habit is different and the incidence of coronary artery disease is lower compared with those of western countries. METHODS: In 1111 cases (452 men, 659 women) aged 63+/-10 years old (range, 40 to 94 years) recruited from a population-based survey performed in 1999, we measured fasting plasma total homocysteine levels and performed bilateral carotid B-mode ultrasound. The participants underwent measurements of other blood chemistries (total cholesterol, HDL cholesterol, glycosylated hemoglobin A(1c), and creatinine). RESULTS: For the total population, the mean total homocysteine level was 10.9 micro mol/L. Total homocysteine levels were higher in men than in women and increased with aging. With multiple linear regression analysis after adjustments for age and sex, the most powerful determinant of total homocysteine levels was serum creatinine (P<0.001). With multiple stepwise regression analysis after adjustments for age, sex, and other confounding factors, total homocysteine was significantly (P<0.05) related to IMT. Furthermore, when mean values of IMT adjusted for age, sex, and other related factors were analyzed across total homocysteine quartiles, IMT (P<0.05) showed a significant trend as total homocysteine level increased. CONCLUSIONS: Plasma total homocysteine levels in Japan are similar to those reported in western countries. Mild hyperhomocysteinemia is an independent risk factor for increased carotid artery wall thickness in Japan as well.

Adult↗

PubMed1989

Alcohol consumption and chronic obstructive pulmonary disease.

This study examined the relationship between lifetime alcohol consumption and respiratory symptoms in 195 subjects (including 111 alcoholics) and FEV1 level in 165 subjects (including 91 alcoholics). After adjustment for age and cigarette smoking status, using multiple logistic regression, lifetime alcohol consumption was a significant predictor of chronic cough and chronic phlegm, but not of any wheeze or persistent wheeze. Multiple linear regression analysis indicated that lifetime alcohol consumption was also a predictor of lower levels of FEV1 in a model that included age, pack-years of cigarette smoking, and an interaction between alcohol consumption and pack-years. The interaction between smoking and alcohol consumption was in a direction opposite to the independent effects of alcohol and smoking, suggesting a protective effect of alcohol with heavier amounts of smoking. Additional study is needed to further assess the relationship between respiratory symptoms and alcohol consumption, and between pulmonary function and alcohol consumption.

Adult↗

PubMed2026

Association between circulating GTP cyclohydrolase 1 concentrations and acute ischemic stroke: an exploratory case-control study in a Chinese population.

BACKGROUND AND OBJECTIVE: Ischemic stroke (IS) is a leading global cause of disability and mortality, characterized by cerebral hypoxia and tissue necrosis. GTP cyclohydrolase 1 (GCH1) regulates endothelial function and oxidative stress; however, whether circulating GCH1 concentrations are altered in acute ischemic stroke (AIS) remains unclear. This exploratory case-control study aimed to investigate plasma GCH1 levels and their associations with clinical characteristics in patients with AIS. METHODS: Seventy-one patients with AIS and 92 controls undergoing routine health examinations were recruited at the Affiliated Hospital of Youjiang Medical University for Nationalities (January 2024-May 2025). Clinical and biochemical data including lipid profiles, C-reactive protein, homocysteine, and National Institutes of Health Stroke Scale (NIHSS) scores (only for patients with AIS) were collected. Plasma GCH1 levels were measured using an enzyme-linked immunosorbent assay. Statistical analyses were performed to evaluate differences between groups and to examine the associations between plasma GCH1 levels and clinical characteristics. Receiver operating characteristic curve analysis was conducted to assess the discriminatory performance of circulating GCH1. RESULTS: Plasma GCH1 concentrations were significantly lower in AIS patients (6.51 ± 3.59 ng/mL vs. 14.32 ± 3.29 ng/mL, p < 0.001). Binary logistic regression analysis showed that lower plasma GCH1 levels were independently associated with AIS (OR = 0.496, 95% CI: 0.385-0.644, p < 0.001), while multiple linear regression analysis demonstrated that AIS was independently associated with lower plasma GCH1 levels (B = -7.687, 95% CI: -9.011 to -6.362, p < 0.001). Plasma GCH1 showed strong discrimination between the two groups (AUC = 0.924, 95% CI: 0.871-0.978) but was not associated with NIHSS scores (Spearman's rho = -0.034, p = 0.778). CONCLUSION: Plasma GCH1 concentrations were lower in patients with AIS than in health-examination controls and showed high apparent discrimination in this dataset. Because GCH1 was measured after stroke onset and the sample-derived threshold was derived in the same case-control sample, these findings do not establish temporality, causality, or clinical diagnostic utility. Prospective multicenter studies including clinically relevant disease controls and independent external validation are required.

Humans↗