450 villages in northern Sumatra were randomly assigned to either participate in a vitamin A supplementation scheme (n = 229) or serve for 1 year as a control (n = 221). 25 939 preschool children were examined at baseline and again 11 to 13 months later. Capsules containing 200 000 IU vitamin A were distributed to preschool children aged over 1 year by local volunteers 1 to 3 months after baseline enumeration and again 6 months later. Among children aged 12-71 months at baseline, mortality in control villages (75/10 231, 7.3 per 1000) was 49% greater than in those where supplements were given (53/10 919, 4.9 per 1000) (p less than 0.05). The impact of vitamin A supplementation seemed to be greater in boys than in girls. These results support earlier observations linking mild vitamin A deficiency to increased mortality and suggest that supplements given to vitamin A deficient populations may decrease mortality by as much as 34%.

The efficacy of Nd-YAG laser photocoagulation in the endoscopic control of haemorrhage from peptic ulcers was shown in a controlled trial. 527 patients admitted consecutively with acute upper gastrointestinal haemorrhage underwent urgent endoscopy. Peptic ulcers were seen in 260. All 138 ulcer patients with stigmata of recent haemorrhage (SRH) accessible to laser therapy were included in the trial (26 inaccessible, 96 no SRH). Patients were stratified into three groups--those with a visible vessel, those with other SRH, and those with clot that could not be washed off before therapy. Laser and control groups were well matched for other factors known to influence prognosis. Overall, 7/70 laser-treated and 27/68 control ulcers rebled (p less than 0.001). Rebleeding occurred from 6/39 treated and 23/43 control ulcers with a visible vessel (p less than 0.001); 0/17 treated and 1/13 ulcers with other SRH (NS); and 1/13 treated and 2/11 control ulcers with overlying clots (NS). 7/70 treated but 24/68 controls required emergency surgery (p less than 0.005). 1 treated patient but 8 control patients died after an episode of rebleeding (p less than 0.05).

The effect of sulindac on renal function and blood pressure was compared with those of placebo, piroxicam, and naproxen in 20 patients with primary hypertension being treated with a diuretic and a beta-blocker. Although the three non-steroidal anti-inflammatory drugs (NSAIDs) did not differ in their effect on renal function (weight, glomerular filtration rate, creatinine clearance) or on serum thromboxane and plasma 6-keto prostaglandin F1 alpha (6-keto PGF1 alpha), blood pressure was significantly lower with sulindac than with placebo, piroxicam, or naproxen. These differences were associated with less renal cyclooxygenase inhibition by sulindac (reflected by urinary thromboxane B2 and 6-keto PGF1 alpha) than by other NSAIDs. The findings suggest that the blood pressure differences reflect vasodilation due to differences in the balance between systemic and renal effects of the NSAIDs.

To determine whether health outcomes in a health maintenance organisation (HMO) differed from those in the fee-for-service (FFS) system, 1673 individuals ages 14 to 61 were randomly assigned to one HMO or to an FFS insurance plan in Seattle, Washington for 3 or 5 years. For non-poor individuals assigned to the HMO who were initially in good health there were no adverse effects. Health outcomes in the two systems of care differed for high and low income individuals who began the experiment with health problems. For the high income initially sick group, the HMO produced significant improvements in cholesterol levels and in general health ratings by comparison with free FFS care. The low income initially sick group assigned to the HMO reported significantly more bed-days per year due to poor health and more serious symptoms than those assigned free FFS care, and a greater risk of dying by comparison with pay FFS plans.

Left ventricular end-diastolic pressure (LVEDP) measured at cardiac catheterisation and simultaneous mitral flow patterns obtained by pulsed Doppler ultrasound scanning were assessed in twenty patients (fourteen males) with ischaemic heart disease. The ratio of passive and active components of mitral flow showed a significant linear correlation with LVEDP. Active (left atrial) mitral flow diminished as left ventricular end-diastolic pressures increased. Mitral flow ratios greater than 2 were always associated with LVEDP greater than 20 mmHg. This application of Doppler echocardiography provides a simple non-invasive method of estimating LVEDP.

The effect of acetazolamide (Az) on exercise performance and muscle mass in acclimatised subjects at an altitude of 4846 m was assessed in 11 subjects and compared with the effect of placebo on 10 other subjects. Exercise performance at 85% maximum heart rate fell by 37% in the Az group and by 45% in controls (p less than 0.05). Weight loss was greater in the placebo group at high altitude (p less than 0.01) and this correlated with the fall in exercise performance (p less than 0.001). During the expedition anterior quadriceps muscle thickness fell by 12.9% in the control group and 8.5% in the Az group (p less than 0.001), while biceps muscle thickness fell by 8.6% in controls and 2.3% in the Az group (p less than 0.001). Measurements of skin-fold thickness indicated a loss of 18% of total body fat in the placebo group and 5% in the Az group by the end of the expedition (p less than 0.001). Calorie intakes at altitudes above 3000 m were low and similar for the two groups. The Az group had fewer symptoms of acute mountain sickness but differences between the two groups were not statistically significant. Acetazolamide is therefore useful for climbers and trekkers who are acclimatised to high altitudes. It could be most useful at extreme altitudes, where maintenance of exercise performance and muscle mass are important.

The vast majority of adverse reactions following immunisation of children with live measles-mumps-rubella (MMR) vaccine were shown in a double-blind, placebo-controlled, cross-over study in 581 twin pairs to be only temporally but not causally related to the vaccination. The true frequency of side-effects caused by MMR vaccine, estimated from the discordance rates of individual signs and symptoms between MMR vaccinees and their placebo-injected twins, was between 0.5 and 4.0%. Moreover, respiratory symptoms, nausea, and vomiting were observed more frequently in the placebo-injected group than in the MMR vaccinated group.

In 12 pregnant mothers fetal sounds and infrasounds were recorded by means of a new compliance matched transducer and compared with a simultaneous ultrasound record of fetal activity. A defined pattern on the fetal phonograph correlated with 86% of the total fetal breathing detected with ultrasound, and a further distinctive pattern was associated with 90% of fetal movements. Examination of the fetal phonocardiogram when the fetus was breathing showed a significant increase in the short-term variability of both the systolic and diastolic times when compared with non-breathing episodes. The median amplitude variabilities for both the first and the second heart sounds were also significantly increased during fetal breathing. Measurement of fetal sounds and infrasounds with a compliance matched transducer offers a non-invasive method for assessment of fetal activity for long periods of time.