Anthropometric correlates of intragastric pressure

Objective. Obesity may increase intra-abdominal pressure on the stomach leading to an increase in intragastric pressure, which in turn induces lower esophageal sphincter relaxation, with subsequent reflux. However, the association between anthropometric measures of total body as well as abdominal obesity and intragastric pressure has not been examined. Material and methods. This prospective cross-sectional study included consecutive patients undergoing manometry at an open access Reflux Center. Standardized measurements of body-weight, height, and waist and hip circumference were prospectively obtained. To assess the intragastric pressure, the perfusion port levels of the catheter were verified to be at the same vertical height (0 mmHg) inside the patient as they were outside the patient during calibration. Correlation between gastric pressure and anthropometric measures was calculated and adjusted for demographic features and presenting symptoms. Results. A total of 322 patients (67% women) with a mean age of 52.5 years were enrolled. The mean values for weight, height, and body mass index (BMI) were 77.2?kg, 168?cm, and 27.5?kg/m², respectively (range 16.0–52.0, median 27.0). The mean intragastric pressure was 2.9?cm H₂O (SD: 1.7). There was a weak, positive correlation between gastric pressure and both BMI (r=0.11, p=0.05) and waist circumference (r=0.11, p=0.06). The associations between gastric pressure and both BMI and waist circumference were relatively unaffected by adjusting for several variables including age, indications for manometry, race, and gender in a multivariable linear regression model. For each unit increase in BMI, there was approximately a 10% increase in intragastric pressure. Conclusions. In this study of consecutive patients with wide-ranging BMI values, there was a weak, positive correlation between intragastric pressure and both BMI and waist circumference. This indicates that obesity operates to increase the risk of gastroesophageal reflux disease (GERD) at least partly by increasing intragastric pressure.     

Anthropometric correlates of blood pressure in normotensive Pakistani subjects

Obesity and hypertension are two major inter-related cardiovascular risk factors. Decrease in adiposity is one of the most effective preventive measures not only in decreasing the overall cardiovascular risk but also the blood pressure. This cross-sectional study measured the effect of various measures of adiposity on blood pressure in normal healthy subjects of Pakistani origin. 400 normotensive subjects (247 males and 153 females) were included in this study. Along with data on co-morbid conditions, two blood pressure readings and several anthropometric measurements were recorded. Age and gender specific analysis was done. Following the WHO cutoffs for Asians, about 52% of our sample population was found to be overweight or obese. Age was not associated with blood pressure indices in males; however it was strongly associated with all blood pressure indices in females. Greater Body Mass Index (BMI), Waist Circumference (WC) and Waist to Height Ratio (WHTR) were associated with higher Systolic and Diastolic Blood pressure. Increasing age was also associated with higher levels of BMI, WC and WHTR. Anthropometric variables however, were more strongly associated with blood pressure indices than age in this sample population. In conclusion, we found WC and WHTR to be strongly associated with blood pressure indices in normotensive Pakistani males.     

Effect of intragastric bile on canine lower oesophageal sphincter pressure.

The effect of intragastric bile on lower oesophageal sphincter (LES) pressure was studied in 7 dogs. Five ml of fresh canine bile was instilled into the stomach, and its effect on LES pressure and intragastric pH was observed for one hour. In a control study 5 ml of physiological saline was used instead of bile. Bile instillation led to a statistically significant increase in LES pressure, which reached its maximum in 20 min. LES pressure returned to the resting level in 60 min. Saline instillation produced no signficant change in LES pressure. The rise in intragastric pH was slight and equal in both groups. The results suggest that bile contamination of gastric juice, at least one of short duration, does not have any immediate harmful effect on LES competence in the dog.     

Effect of pentagastrin and caerulein on intragastric pressure in the dog.

When gastric acid was not neutralized, doses of pentagastrin as small as 1 mug kg-1 hr-1 decreased intragastric pressure in dogs. When gastric acid was neutralized the smallest effective dose of pentagastrin was 8 mug kg-1 hr-1 which is 16 times the D50 for acid secretion. Thus the decrease in intragastric pressure by small doses of pentagastrin is mediated at least in part by acid secretion. Even with gastric neutralization, a dose of caerulein as small as 63 ng kg-1 hr-1, which is the D50 for pancreatic protein secretion, decreased intragastric pressure. These findings support the view that inhibition of gastric pressure occurs with physiological doses of the cholecystokinin-like peptide caerulein but only with pharmacological doses of pentagastrin.     

Anthropometric and lifestyle correlates of serum lipoprotein and apolipoprotein levels among normal non-smoking men and women

The relationship between serologic predictors of coronary risk and anthropometric as well as lifestyle characteristics was investigated in 61 men (37.5 +/- 8.5 yrs) and 33 women (40.1 +/- 9.0 yrs). All subjects were healthy non-smokers, mostly middle-class bank employees. In bivariate analysis, among both genders the ratio of waist-to-hip circumference (WHR) was the single best predictor of levels of serum LDL-cholesterol, apolipoprotein B, VLDL-cholesterol and triglycerides (positive association) as well as HDL-cholesterol and apolipoprotein A-I (inverse association). In men, body fat as estimated from bioelectrical impedance measurement was the second best predictor of lipoprotein and apoprotein concentrations, whereas in women it was the body mass index (BMI). The additional independent predictive power of WHR and body fat for the lipid profile was tested in multivariate analysis by adding WHR and body fat sequentially to regression models containing already BMI, endurance capacity, exercise, alcohol consumption and age. For example, explained variance of triglyceride distribution rose from 26.3 to 35.1% (P = 0.01 for increase) when body fat was entered into the regression equation, or inclusion of WHR into a model already containing age, the behavioral variables, BMI, and body fat increased the explained variance of LDL/HDL-cholesterol ratio from 20.9 to 27.6% (P = 0.04 for increase). In women, the same regression models were even slightly more predictive for the serum lipid profile. Endurance capacity was related to a low atherogenic risk lipid profile in bivariate analysis but lost much of its predictive power in multivariate analysis, which confirms that the effect of fitness on lipid levels is probably mediated in part by a low body fat content. It is concluded from this cross-sectional investigation that studies which focus on associations between lifestyle and serologic predictors of atherogenic risk should possibly include the WHR and a measure of body fat, since the latter two appear to be closer correlates of serum lipoprotein and apolipoprotein levels than BMI or single behavioral factors, at least among male non-smokers.     

Nutritional correlates of blood pressure in elderly Chinese

Dietary intakes of various nutrients, urinary electrolyte levels from a casual urine sample, and BP were determined in 425 active men and women aged 60 and above (mean age 70.6 years) living in the community. After exclusion of subjects taking Western or Chinese medicines, correlations were seen between body mass index and diastolic blood pressure (DBP, r = 0.15, P less than 0.01), between calcium intake and systolic blood pressure (SBP, r = 0.14, P less than 0.02) and retinol intake and SBP (r = -0.14, P less than 0.03). There was no significant correlation between BP and casual urinary Na/Cr, K/Cr, Na/K or Ca/Cr ratios. Fewer correlates were seen compared to younger age groups. These results suggest that dietary modification of BP based on studies in Caucasian communities of all ages may not apply to elderly Chinese populations.     

Biochemical and histologic correlates of ventricular end-diastolic pressure

The associations of elevated left ventricular (LV) and right ventricular (RV) end-diastolic pressure (EDP) were evaluated in 28 patients with non-ischemic congestive cardiomyopathy. Right-sided endomyocardial biopsies from each patient were evaluated for ATP content, percent fibrosis and myocardial fiber diameter. The resting RVEDP and LVEDP and the post-angiographic LVEDP were correlated with the results from the biopsies. There was a correlation of the LVEDP with the RVEDP (r=0.67, P<0.001) by a linear plot. There was no correlation of any EDP measurement with the percent fibrosis. There was, however, a rough correlation of the myocardial fiber diameter with RVEDP (r=0.40, P<0.05). Myocardial ATP content correlated with the RVEDP (r=−0.53, P<0.005), the LVEDP (r=−0.65, P<0.001) and the post-angiographic LVEDP (r=−0.72, P<0.001). These data demonstrate than an elevated ventricular EDP correlates most closely with depressed levels of myocardial ATP. The myocardial cell diameter correlated less well and there was no correlation of EDP with fibrosis. Metabolic factors may be more important than histologic parameters in the elevated ventricular EDP of non-ischemic congestive cardiomyopathy.     

Pulse pressure correlates with leukoaraiosis in Alzheimer disease

The relation between pulse pressure (PP) and Alzheimer disease (AD) remains unclear. We performed this study to investigate the relation between PP and AD and the impact of PP to impair cognitive performance on this relationship. It is a cross-sectional study from the Neurology Memory Clinic of Chungnam National University Hospital and five senior welfare centers in the city of Taejon, Korea. A cohort of 75 patients with AD and 117 control subjects were enrolled for the study. PP was significantly higher whereas mean arterial pressure (MAP) was lower in patients with AD than those of control subjects. Elevated serum total cholesterol (TC) level was significantly associated with both PP and MAP in control subjects as well as patients with AD. We found a significant relationship between PP and cerebral white matter changes (WMCs) in AD. PP changes correlate with leukoaraiosis in AD.     

Twenty-one-year trends and correlates of pressure to change drinking

Background: The vast majority of individuals with alcohol problems in the United States and elsewhere do not seek help. One policy response has been to encourage institutions such as criminal justice and social welfare systems to mandate treatment for individuals with alcohol problems (Addiction, 1997; 92 :1133). However, informal pressures to drink less from family and friends are far more common than institutional pressures mandating treatment (Addiction, 1996; 91 :643). The prevalence and correlates of these informal pressures have been minimally studied. Methods: This analysis used data from 5 Alcohol Research Group National Alcohol Surveys (NAS) collected at approximately 5‐year intervals over a 21‐year period (1984 to 2005, pooled N = 16,241) to describe the patterns of pressure that drinkers received during the past year from spouse, family, friends, physicians, police, and the workplace. Results: The overall trend of pressure combining all 6 sources across all 5 NAS data sets indicated a decline. Frequent heavy drinking and alcohol‐related harms also declined, and both were strong predictors of receiving pressure. Trends among different sources varied. In multivariate regression models, pressure from friends showed an increase. Pressure from spouse and family showed a relatively flat trajectory, with the exception of a spike in pressure from family in 1990. Conclusions: The trajectory of decreasing of pressure over time is most likely the result of decreases in heavy drinking and alcohol‐related harm. Pressure was generally targeted toward higher risk drinkers, such as heavy drinkers and those reporting alcohol‐related harm. However, demographic findings suggest that the social context of drinking might also be a determinant of receiving pressure. Additional studies should identify when pressure is associated with decreased drinking and increased help seeking.     

Role of intragastric pressure, pH, and pepsin in gastric ulceration in the rat.

A method of continuous gastric perfusion with "artificial gastric juice" was used in a study of individual factors (intragastric pressure, pH, and pepsin) known to participate in the pathogenesis of peptic ulcers. This method allowed change of only one factor at a time, while the other two remained constant. The gastric mucosa of normal rats, fasted for 48 hr, was found to be resistant to the ulcerogenic effects of artificial gastric juice perfused through the stomach for 6 hr without increasing the intragastric pressure. Perfusion of hydrochloric acid (pH 1.3) under increasing pressure produced ulceration of the corpus as well as forestomach portion of the stomach. The degree of gastric ulceration paralleled increases in intragastric pressure, acidity, and pepsin proteolytic activity. Inhibition of pepsin activity by a pepsin inhibitor protected the gastric mucosa even at the very low pH of 1.3. These results demonstrate that under the experimental conditions used, hydrochloric acid alone in the absence of pepsin does not produce ulceration of the rat stomach.     

Inconsistencies in the correlates of blood pressure and heart rate

Various correlates of blood pressure (BP) and resting heart rate (HR) were compared in a study population of 1667 male and 520 female factory employees in Israel. The strong positive association between HR and both diastolic and systolic BP described in other epidemiologic studies was again evident. However, the correlates of HR and BP did not coincide. In multiple regression analyses age was found to be positively associated with BP in both sexes, whereas it was only moderately associated with HR in males and inversely associated with HR in females. Relative weight was positively associated with BP in both sexes but its association with HR was linear in young males and older females and U- or J-shaped in the other sub-groups. Cigarette smoking was inversely associated with diastolic BP in several subgroups but was positively associated with HR in most sub-groups. Ethnic-related variations in blood pressure, where found, did not parallel any differences in HR and in one group they were contradictory. The inconsistencies in the correlates of HR and blood pressure may reflect different mechanisms by which certain factors influence BP with varying effects on the HR.     

Psychological correlates of elevated arterial pressure and smoking in adolescents

Psychological characteristics of adolescents with risk factors of cardiovascular disease (elevated arterial pressure - EAP - and smoking) were examined in Moscow secondary school pupils aged 12-14 years, using an abridged variant of the psychodiagnostic MMPI questionnaire. The following characteristics were found to differentiate these youngsters from a comparable control group of youngsters without the mentioned risk factors: increased anxiety, insufficient self-confidence, deficient understanding of the motives of their own behaviour, and a tendency to deny their own psychological problems. These characteristics are most pronounced in youngsters with neurocirculatory asthenia of hypertensive type. There were also found specific psychological characteristics differentiating youngsters with EAP from smokers without EAP. The authors point to the possibility of working out differentiated methods of psychological intervention in EAP and smoking in adolescents.