Improved accuracy of indirect blood pressure measurement in patients with obese arms

We studied 20 patients with moderate to severe obesity (body mass index 37 +/- 8 kg/m2) with obese arms (arm circumference 37 +/- 4 cm). Their blood pressure was measured directly in the brachial artery in one arm and simultaneously indirectly in the other arm using either a large standard cuff (rubber bag 12 x 35 cm) or a new cuff (the Tricuff, Pressure Group AB, Stockholm) containing three rubber bags of different sizes, which automatically selected the appropriately sized bag in relation to arm circumference. Both cuffs showed a significant overestimation of the diastolic blood pressure (standard cuff 13 mm Hg, P < .001, Tricuff 6 mm Hg, P < .01). The error of the standard cuff was significantly greater than that of the Tricuff (P < .001). The differences in systolic blood pressure between the intraarterially and the indirectly measured results were small (0.2 to 3 mm Hg) and not statistically significant with either cuff. The new Tricuff offered an advantage as compared to a large standard cuff in terms of a lesser overestimation of the diastolic blood pressure. In practical terms, this should lead to a reduction in the overestimation of diastolic hypertension in obese individuals.

The Christmas factor in obesity therapy

The effect of Christmas time on body weight development was measured in 46 obese patients in maintenance therapy at the Obesity Unit of the Karolinska Hospital and in 76 hospital staff controls of similar sex and age distribution. In controls a statistically significant weight increase of 0.4 +/- 0.8 (s.d.) kg (P < 0.001) was found, whereas the mean increase in the obese patients of 0.6 +/- 2.4 kg was not statistically significant. Little variation in weight development over Christmas was found in controls, whereas the weight change in the obese group ranged from +6.1 to -8.8 kg over the 2-3 weeks. Seasonal variation in body weight has been attributed to circadian rhythms. Cultural food habits may also play a role.

Eating behavior in continuous ambulatory peritoneal dialysis and hemodialysis patients

Three groups consisting of 12 subjects each (continuous ambulatory peritoneal dialysis [CAPD] patients, hemodialysis patients, and healthy controls) matched for age, sex, and body weight were invited to a test meal for the study of hunger, fullness, and food preferences. They were served an excess portion of hash served on a plate placed on a hidden scale ("VIKTOR"), which was connected to a computer registering the eating process on-line. The patients filled in visual analogue scales (VAS) concerning appetite and food preferences before and after the test meal. Mean total intake of food (+/- SD) was significantly higher for healthy controls (357 +/- 175 g) compared with hemodialysis patients (295 +/- 105 g), which in turn was higher than in CAPD patients (206 +/- 70 g). Eating velocity was lower in both dialysis groups compared with controls. CAPD patients experienced less hunger and desire to eat compared with hemodialysis patients and controls. The reason for the low eating drive in CAPD patients despite their great need for protein and calories is unknown, but might be explained by gastric retention, insufficient dialysis, metabolic effects of the high sugar load from the dialysate, or combinations of these factors.

Effect of short-term fasting on nocturnal melatonin secretion in obesity

To investigate whether the function of pinealocytes is altered in obesity, nocturnal melatonin (MT) secretion was determined in nine healthy subjects and compared with that of eight obese individuals. Serum MT levels were measured every second hour between 6:00 PM and 8:00 AM, and total nocturnal MT secretion (as reflected by the MT incremental area), MT peak time, and nocturnal urinary MT excretion were determined. None of these parameters differed significantly in the two groups. The obese subjects were reinvestigated after 2 days of complete fasting. This caused a decrease in body weight and basal blood glucose levels of 2.6 +/- 0.2 kg (mean +/- SEM, P less than .001) and 1.5 +/- 0.2 mmol/L (P less than .001), respectively, whereas serum cortisol levels remained unchanged. Short-term fasting reduced nocturnal MT secretion, as evidenced by MT incremental areas, which were reduced from 2.01 +/- 0.26 before fasting to 1.64 +/- 0.26 nmol/L.h after fasting (P less than .02). MT secretion peaks were reached simultaneously, and urinary MT excretion values did not change significantly in fasting. To see whether glucose supplementation during short-term fasting would normalize nocturnal MT secretion, we gave an additional seven obese subjects eight small oral doses of glucose (each dose, 0.5 g/kg body weight) at regular intervals during a 2-day fast. Their body weight decreased by 2.8 +/- 0.4 kg (P less than .001), but blood glucose and cortisol concentrations were similar before and after the glucose-supplemented fast, as was the nocturnal MT secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Eating behaviour in obese and normal weight 11-year-old children

The eating behaviour of 23 normal weight and 20 obese 11-year-old children was measured by the computerized eating monitor VIKTOR. The total intake of food, duration of consumption, rate of consumption and the relative rate of consumption were measured during two lunch meals. Subjective motivation to eat and food preferences were also measured. The obese children ate faster (P less than 0.05) and did not slow down their eating rate towards the end of the meal (P less than 0.05) as much as normal weight children. The obese children also described themselves as having less motivation to eat before lunch than normal weight children (P less than 0.05). A deficient satiety signal or an impared response to such signals in obese subjects could possibly explain these differences found.

A dietary fibre supplement in the treatment of mild hypertension. A randomized, double-blind, placebo-controlled trial

OBJECTIVE

To study the effects of a dietary fibre supplement given as monotherapy upon blood pressure in mildly hypertensive patients.

DESIGN

The investigation was performed as a prospective randomized, double-blind, placebo-controlled trial for 3 months.

SETTING

Patients attending an outpatient hypertension clinic in a hospital.

PATIENTS

Hypertensive patients with a minimum of two diastolic blood pressure (DBP) readings greater than 90 mmHg during a 2-week run-in period were included. Of the 65 patients enrolled, 63 were randomized (32 fibre, 31 placebo). Six patients did not complete the trial.

INTERVENTION

Patients were treated with either fibre (7 g/day) or matching placebo.

MAIN OUTCOME MEASURE

Based on previous studies, the a priori hypothesis was that dietary fibre supplementation could reduce blood pressure in hypertensive patients.

RESULTS

Body weight was significantly reduced in the fibre group. Dietary fibre significantly reduced DBP and fasting serum insulin. However, no correlation between changes in body weight and systolic blood pressure or DBP was found.

CONCLUSION

A dietary fibre supplement can lower DBP in mildly hypertensive patients independent of changes in body weight.

Pregnancy, weight cycling and weight gain in obesity

Pregnancy constitutes a biological cause of weight cycling. Since repeated weight variation has been associated with sustained weight increase and subsequent metabolic complications, the role of pregnancy in affecting body weight was analysed retrospectively in a group of 128 severely obese patients at the obesity unit. Their present mean age was 47.8 +/- 10.7 years, the mean age at birth of their first child 24.1 +/- 5.1 years and their mean present BMI was 37.8 +/- 5.5 kg/m2 (s.d.). Seventy-three percent of the women reported a weight retention of more than 10 kg one year after delivery. The median number of other weight cycling events was seven. Such cycling did not correlate to present BMI or weight increase during any pregnancy. Weight increases during subsequent pregnancies were not correlated to each other. The results support the hypothesis that for women who develop severe obesity, their pregnancy-related weight increases contribute substantially to their body weight development.

The sleep apnoea syndrome in obesity: risk of sudden death

A total of 34 severely obese men with a history of heavy snoring and excessive daytime sleepiness indicative of obstructive sleep apnoea syndrome (OSAS) were studied prospectively. Their mean age was 46 years, and mean body mass index was 41.6 kg m-2. During a 4-year follow-up, 15% (5/34) of these subjects died (three cases of acute myocardial infarction and two cases of pulmonary oedema), all of them suddenly and unexpectedly, outside hospital. On autopsy the degree of atherosclerosis was found to be moderate in all cases. In 68% (15/22) of the men a pathological apnoea index (mean value 46 +/- 20) confirmed the OSAS diagnosis. Exercise tests and neurological examinations did not reveal any other causes of daytime sleepiness. Mean blood pressure at rest and during exercise was normal, and mean serum lipid and blood glucose levels were normal. Spirometry revealed intrapulmonary restrictive changes that could not be attributed to the heavy thoracic wall. Compliance was reduced to about 50% of reference values, and the mean pCO2 level (5.8 kPa) was close to the upper reference limit. Blood tests suggested that high alcohol consumption may be an important factor contributing to OSAS. These results demonstrate that morbidly obese men with a history of OSAS have a high risk of sudden cardiovascular death, despite the absence of other conventional risk factors.

Nocturnal melatonin secretion in thyroid disease and in obesity

OBJECTIVE

The purpose was to investigate whether the function of the pinealocytes is changed in patients with disturbed metabolic rate or in subjects with marked obesity.

DESIGN

Venous blood was sampled every second hour between 1800 and 0800 h, and urine collected between 2200 and 0700 h.

PATIENTS

Eight patients with thyrotoxicosis, six with primary hypothyroidism, eight with maturity-onset obesity, and 12 healthy controls were included in the study.

MEASUREMENTS

Peak serum melatonin values during the night, total nocturnal melatonin secretion (estimated by melatonin incremental areas), and urinary excretion of melatonin were determined in each participant.

RESULTS

Patients with hypothyroidism were found to have higher peak serum melatonin values, total nocturnal melatonin secretion, and urinary excretion of melatonin than normal individuals (Peak melatonin values: 0.55 +/- 0.13 vs 0.27 +/- 0.04 nmol/l, respectively; P less than 0.05. Melatonin incremental areas: 3.38 +/- 0.80 vs 1.45 +/- 0.26 nmol/l h; P less than 0.05. Melatonin excretion: 0.140 +/- 0.023 vs 0.081 +/- 0.013 nmol/9 h; P less than 0.05). Neither of these values differed significantly from the normal in patients with thyrotoxicosis or obesity. Although thyrotoxic patients thus released a normal amount of melatonin during the night, their melatonin secretion peak was phase advanced (melatonin secretion peak appearing at 1.1 +/- 0.5 h in thyrotoxic, and at 3.4 +/- 0.5 h in normal participants; P less than 0.01). No such phase shifts were seen in patients with obesity or hypothyroidism.

CONCLUSIONS

These findings imply that both hypothyroid and thyrotoxic patients have disturbed pineal function, which is not the case in patients with obesity. The mechanism underlying these observations remains to be elucidated.