Effectiveness of non-cardiac preoperative testing in non-cardiac elective surgery: a systematic review.

Elective surgery is usually preceded by preoperative diagnostics to minimize risk. The results are assumed to elicit preventive measures or even cancellation of surgery. Moreover, physicians perform preoperative tests as a baseline to detect subsequent changes. This systematic review aims to explore whether preoperative testing leads to changes in management or reduces perioperative mortality or morbidity in unselected patients undergoing elective, non-cardiac surgery. We systematically searched all relevant databases from January 2001 to February 2011 for studies investigating the relationship between preoperative diagnostics and perioperative outcome. Our methodology was based on the manual of the Ludwig Boltzmann Institute for Health Technology Assessment, the Scottish Intercollegiate Guidelines Network (SIGN) handbook, and the PRISMA statement for reporting systematic reviews. One hundred and one of the 25 281 publications retrieved met our inclusion criteria. Three test grid studies used a randomized controlled design and 98 studies used an observational design. The test grid studies show that in cataract surgery and ambulatory surgery, there are no significant differences between patients with indicated preoperative testing and no testing regarding perioperative outcome. The observational studies do not provide valid evidence that preoperative testing is beneficial in healthy adults undergoing non-cardiac surgery. There is no evidence derived from high-quality studies that supports routine preoperative testing in healthy adults undergoing non-cardiac surgery. Testing according to pathological findings in a patient's medical history or physical examination seems justified, although the evidence is scarce. High-quality studies, especially large randomized controlled trials, are needed to explore the effectiveness of indicated preoperative testing.

[Food-drug interactions: an underestimated risk]. / Interaktionen zwischen Medikamenten und Ernährung. Verkannte Ursache von Nebenwirkungen und Therapieversagen.

With only few exceptions, administration of medicaments should, in principle, be independent of food intake (at least half an hour before or two hours after eating). This ensures uniform and assessable bioavailability. However, it also entails the risk that the patient is more likely to forget to take medication postponed to 2 hours after a meal, than when it is directly coupled to a meal. Certain foodstuffs or food constituents, such as, for example, grapefruit, Seville orange juice, red wine, alcoholic drinks in general, or large quantities of caffeine and garlic should be avoided during drug treatment. In addition, specific interactions with certain drugs must also be taken into account (e.g. MAO inhibitors and tyramine, curamine and vitamin K).

Results and efficacy of public screening for hypercholesterolemia: the Bavarian Cholesterol Screening Project.

Hypercholesterolemia is a risk factor for the development of coronary disease. It does not present with symptoms and can be diagnosed by laboratory examination only. Screening is the only means to detect subjects at risk at a time when preventive measures can effectively be applied. We therefore initiated the Bavarian Cholesterol Screening Project (BCSP). Occasional screening was performed in 150,089 subjects (81,286 women, 68,803 men) in 214 campaigns. The mean cholesterol value was 243 +/- 52 mg/dl for women and 231 +/- 53 mg/dl for men; 37.3% of women and 38.1% of men had values of 201-250 mg/dl, 42.2% of women and 33.7% of men values > 250 mg/dl. Also, the following risk factors were recorded: smoking in 11.3% of women and in 20.2% of men, hypertension in 19.8% of women and 17.4% of men, diabetes mellitus in 4.2% of women and 4.1% of men, obesity in 16.8% of women and 20.9% of men, and a family history of myocardial infarction in 34.8% of women and 26.0% of men. Of the 27,084 men who had their cholesterol checked for the first time, 35.6% had levels between 201 and 250 mg/dl, and 22.9% had levels above 250 mg/dl. Of the 27,870 women whose cholesterol level had not been checked before, 38.8% had levels between 201 and 250 mg/dl, and 27.1% had levels above 250 mg/dl. More than 70% of the subjects with levels between 200 and 250 mg/dl had at least one additional risk factor. We conclude, on the basis of this study, that the risk factor hypercholesterolemia is unknown in as much as 20% of the population of Bavaria. These newly detected subjects were offered the opportunity to recognize this risk and take subsequent measures of prevention. Screening projects for hypercholesterolemia therefore can be an effective means of improving public health.

The waist-to-hip ratio corrected for body mass index is related to serum triglycerides and high-density lipoprotein cholesterol but not to parameters of glucose metabolism in healthy premenopausal women.

Android obesity is associated with metabolic disorders, but the causality of this relationship remains unclear. We investigated the association of body mass index (BMI) and waist-to-hip ratio (WHR) with hormones, glucose tolerance, insulin sensitivity, serum lipoproteins, and the serum activity of hepatic enzymes in 40 healthy premenopausal women (BMI 19.2-46.1, mean 32.6 +/- 1.3 kg/m2; WHR 0.68-1.01, mean 0.82 +/- 0.02). BMI correlated with WHR (r = 0.52, P < 0.01). After correction for WHR, BMI was negatively correlated with high-density lipoprotein cholesterol and positively with total and very low density lipoprotein triglycerides, insulin sensitivity, blood glucose, serum insulin and glucagon. After adjustment for BMI, WHR was significantly associated with high-density lipoprotein cholesterol, total and very low density lipoprotein triglycerides, and the serum activities of hepatic enzymes but not with insulin sensitivity, blood glucose, serum insulin, or glucagon. According to these results, body fat distribution assessed by WHR is related to hypertriglyceridemia and alterations in hepatic function such as a fatty liver. WHR is not primarily related to glucose metabolism in healthy premenopausal women without preexisting metabolic disorders such as glucose intolerance. Therefore the observable association between android obesity and manifest impairment in glucose metabolism may develop secondarily during persisting hyperinsulinemia, which itself is primarily related to obesity. Thus an android body fat distribution may rather be an accompanying feature than a predictor of impaired glucose tolerance and insulin resistance.

[Cardiovascular risk factors in former and new Germany. City comparison of Leipzig/Nürnberg on the incidence of increased cholesterol values and other cardiovascular risk factors]. / Kardiovaskuläre Risikofaktoren in den alten und neuen Bundesländern. Städtevergleich Leipzig/Nürnberg zur Häufigkeit erhöhter Cholesterinwerte und anderer kardiovaskulärer Risikofaktoren.

FUNDAMENTALS: Cardiovascular risk factors depend decisively on living conditions and nutrition. The aim of the present study was to establish whether the different living conditions in the eastern and western parts of Germany were associated with differences in the frequency and severity of these risk factors. METHOD: In Leipzig, 15,291 people (9,600 women and 5,691 men), in Nuremberg 8,387 (4,559 women and 3,828 men) were examined either after responding to a public appeal, or in the factory, etc. RESULTS: Clearly elevated cholesterol levels (> 250 mg/dl) were found in 33.8% of the men, and 35.9% of the women in Leipzig, and in 39.1% of the men and 50.7% of the women in Nuremberg. This larger incidence of treatment-requiring hypercholesterolemia in Nuremberg was distributed throughout all age groups up to the age of 60. Hypertension was significantly more common among the 30 to 80-year-old women, and the 20 to 40-year-old and 50 to 80-year-old men in Leipzig. the frequency of cigarette smoking, diabetes mellitus and overweight did not differ significantly between the two cities. In cases with known dyslipoproteinemia, drug treatment was rarely applied, and the therapeutic aim of a cholesterol level < 200 mg/dl, was achieved in only 2-6% of those treated. The most significant difference with respect to cardiovascular risk factors was serum cholesterol. It is possible that a higher ingestion of monounsaturated fatty acids and more physical activity may be responsible for the lower cholesterol levels in Leipzig.

Influence of fiber, xylitol and fructose in enteral formulas on glucose and lipid metabolism in normal subjects.

To verify the benefit of nonglucose carbohydrates and fiber in enteral formula diets we studied the postprandial metabolism of eight healthy subjects after the intake of two helpings (25 g carbohydrates each) of five commonly used enteral formulas over 4 h. There were no significant differences in postprandial concentrations of blood glucose among the formulas. The area under the curve of postprandial insulin values, however, was significantly smaller after consumption of the fructose-containing formula (1948 +/- 285 microU min ml-1, P < 0.05) than after fiber-free (3222 +/- 678 microU min ml-1) or two fiber-containing products (2664 +/- 326 microU min ml-1, P < 0.05; and 3040 +/- 708 microU min ml-1, P < 0.05). The insulin area of the xylitol-containing formula (2307 +/- 364 microU min ml-1) was significantly smaller compared to the fiber-free product (P < 0.05). In addition, we found the postprandial increase in triglycerides to be significantly higher after the xylitol-containing formula (from 0.93 +/- 0.14 to 1.25 +/- 0.22 mmol/l) than after the fiber-free product (from 0.82 +/- 0.13 to 0.97 +/- 0.16 mmol/l, P < 0.05) or the two fiber-containing products (from 0.88 +/- 0.16 to 0.96 +/- 0.18 mmol/l, P < 0.05; and from 0.80 +/- 0.08 to 0.95 +/- 0.10 mmol/l, P < 0.05). We conclude that a patient with type II diabetes may benefit from replacing glucose and glucose-equivalent carbohydrates with fructose or xylitol.

[Effect of diuretics on serum lipoproteins]. / Der Einfluss von Diuretika auf die Serumlipoproteine.

UNLABELLED: BASICS: Drug treatment of the risk factor hypertension has not led to the expected reduction in morbidity and mortality of coronary arterial disease. A negative effect of antihypertensive drugs on the lipid metabolism is under discussion as a possible cause. MAIN TOPICS: Both the commonly employed thiazide diuretics and chlorthalidone and the loop diuretics furosemide, piretanide and xipamide lead, to varying extents, to an increase in total and LDL cholesterol as well as triglycerides in subjects with normal metabolism. In addition, some diuretics lower the levels of protective HDL cholesterol. These side effects can be avoided--at least in part--by a combination with such drugs as prazosin, pindolol or captopril, which have a favorable effect on metabolism. CONCLUSION: It is recommended to carefully monitor serum Lipoproteins during diuretic treatment so that possible adverse changes may be counteracted by appropriate measures.

Benefit from hypocaloric diet in obese men depends on the extent of weight-loss regarding cholesterol, and on a simultaneous change in body fat distribution regarding insulin sensitivity and glucose tolerance.

Obesity and an android body fat distribution are related to metabolic disorders. We investigated the interdependences between metabolism, overweight, and body fat distribution in 40 moderately obese men before and after weight-loss. Correlations between metabolic parameters and body mass index (BMI) or waist to hip ratio (WHR) were much weaker in this exclusively obese population than in subjects of all weight categories, but the association between BMI and glucose tolerance (r = -.46, P less than .01) increased significantly after weight-loss. The improvement of metabolic parameters was much stronger in men who achieved normal weight (BMI less than 27 kg/m2) than in those who remained obese (BMI greater than 30 kg/m2, P less than .05). The WHR decreased during the diet (P less than .001), and this decrease and the extent of weight-loss were significantly correlated to an increase in insulin sensitivity (r = -.41, P less than .01) and a decrease in glucose area after an oral glucose load (r = .34, P less than .05). The decrease in apolipoprotein B, total cholesterol, and low-density lipoprotein (LDL) cholesterol was significantly correlated only to the extent of weight-loss (r = .34, .31, and .39, respectively; P less than .05). We conclude that it is best to reach normal weight for the normalization of metabolic aberrations. The reduction of cholesterol appears to be dependent on the extent of weight-loss, while the improvement in insulin sensitivity and glucose tolerance apparently is related to both the extent of weight-loss and to a change toward a less android body fat distribution.

Body fat distribution and serum lipoproteins in relation to age and body weight.

Android obesity is reported to be a risk factor for coronary heart disease and aberrations in lipid metabolism, but so far its association with other risk factors such as age and overweight has not been clearly analyzed. We therefore investigated the relationship between the waist-to-hip ratio, age, body mass index and serum lipoproteins in 305 probands (158 men, 147 women), while body mass index was kept constant in all age groups. Waist-to-hip ratio correlated with both age (r = 0.441) and body mass index (r = 0.532) in simple linear correlation analysis (P less than 0.001). In stepwise multiple regression analysis we found in both sexes a first step dependence on age for total and LDL-cholesterol (P less than 0.001), a first step dependence on waist-to-hip ratio for triglycerides (P less than 0.001), VLDL-triglycerides (P less than 0.001) and VLDL-cholesterol (P less than 0.001 for men, P less than 0.05 for women), and an inverse first step dependence on body mass index for HDL-cholesterol (P less than 0.05 for men, P less than 0.001 for women). From these results we propose an independent association between waist-to-hip ratio and triglycerides while the relation to total and LDL-cholesterol is determined by age. HDL-cholesterol, on the other hand, is influenced by body fat mass and independent from age or body fat distribution.

Beta-endorphin plasma levels and their dependence on gender during an enteral glucose load in lean subjects as well as in obese patients before and after weight reduction.

It is speculated that endogenous opioid peptides are involved in glucose metabolism and that their homeostasis might be disturbed in obesity. Despite a different response of the pancreatic beta-cells after beta-endorphin and naloxone injections between obese patients and normal weight controls, there is little knowledge concerning the direct influence of a glucose load on beta-endorphin plasma levels, especially with respect to various nutrition states. During exploration of this topic we gained further insight on the difference of basal beta-endorphin plasma levels between normal and overweight persons. We compared beta-endorphin plasma levels during an oral glucose load in 60 obese, non-diabetic patients and in 20 normal weight controls. We also studied 40 of the obese patients after a weight reduction of 2.1 kg/m2. The following results were obtained: (1) Normal weight females have significantly lower (P less than 0.05) basal beta-endorphin levels compared to the male controls. This difference in gender is abolished in obesity where female and male patients do not differ in basal beta-endorphin plasma levels. Therefore, the difference between normal and overweight persons in beta-endorphin plasma levels was restricted to the subgroup of females. We suppose that former neglect of this difference in gender explains most of the so far reported discrepant results. (2) During the oral glucose tolerance test the beta-endorphin plasma values remained constant in the obese group. Despite improved insulin sensitivity after weight reduction there was still no change of beta-endorphin plasma levels both during the OGTT and when compared to the values before weight reduction.(ABSTRACT TRUNCATED AT 250 WORDS)

[Obesity, body fat distribution and the incidence of breast, cervical, endometrial and ovarian carcinomas]. / Adipositas, Körperfettverteilung und Inzidenz von Mamma-, Zervix-, Endometrium- und Ovarialkarzinomen.

The connection of body fat distribution (BFD) and the risk of developing mammary, cervical, endometrial or ovarian carcinoma was ascertained for 163 patients with carcinoma (mean age 49.9 [19-78] years) and 489 controls of comparable age and body-mass index. BFD was expressed as the ratio of waist and hip circumference (T/H ratio of 0.822 vs 0.781 and 0.826 vs 0.789, respectively; P less than 0.01). In premenopausal women with mammary or cervical carcinoma and in all postmenopausal women BFD was similar to that in the control subjects. A common cause of android obesity and ovarian or endometrial carcinoma may be a reduction of sex-hormone-binding globulins with an elevated serum level of free androgens and oestrogens.

Reduction of lipoprotein (a) by weight loss.

Lipoprotein (a) is believed to be an independent risk factor for atherosclerosis. Fat modified diets or lipid lowering drugs seem to have little effect on Lp(a) serum levels. We tested the possibility of lowering Lp(a) by weight reduction and examined the correlation between Lp(a) serum levels, other lipoproteins, body weight and body fat distribution in 53 obese patients. Weight reduction by a 4000 kJ protein enriched diet for four weeks led to a mean 19 percent reduction of Lp(a) serum levels in men (P less than 0.01) and a mean 30 percent reduction in premenopausal women (P less than 0.001). Significant correlations could neither be demonstrated between Lp(a) and other lipoproteins nor between initial Lp(a), overweight and body fat distribution. This implies that an intraindividual interdependence between Lp(a) and body weight seems to be possible although an interindividual correlation can not be shown.