Should people be physically active outdoors on smog alert days?

BACKGROUND: Given the importance of physical activity to well-being, there is a need to encourage people to be physically active year-round. At the same time, many people are vulnerable to adverse health effects from air pollution, especially on smog alert days. This study was undertaken to determine when air pollution levels tend to be lowest so that the public can modify strenuous outdoor activity accordingly. METHODS: Existing hourly air pollution data for Toronto were analyzed to determine how pollutant levels varied from hour to hour throughout each 24-hour day, to identify the times when pollution levels are at their lowest on average. RESULTS: Pollutant levels vary throughout the day, with concentrations of some pollutants (such as ozone, particles and sulphur dioxide) being highest during mid-day, and others (such as carbon monoxide and nitrogen dioxide) being highest with morning rush hour. Overall, pollutant concentrations tend to be lowest before seven a.m. and after eight p.m. INTERPRETATION: The public should be encouraged to maintain regular physical activity outdoors while monitoring any air pollution-related symptoms. The intensity of outdoor activity should be reduced, or activities replaced with indoor exercise, at those Air Quality Index (AQI) levels that trigger individual symptoms and when AQI values exceed 50. Where possible, strenuous activity should be taken when and where air pollution levels tend to be lowest, namely early in the morning and in low-traffic areas. More research is required to guide development of health protective advice on exercising when air quality is poor.     

Urine collection pads: are samples reliable for urine biochemistry and microscopy?

The aim of the study was to validate the reliability of samples obtained with urine collection pads (UCP) for selected laboratory biochemical analyses, urine cell microscopy, and bedside semi-quantitative stick urinalysis. A series of laboratory experiments was performed to test agreement between urine concentrations, or results, before and after passage through a UCP (incubated for 37°C for 15 min). The following urinalyses were performed: electrolytes, calcium, phosphate, urate, osmolality, pH, protein, catecholamines, toxicology for drugs of abuse, stick urinalysis for glucose, ketones, protein, blood, leucocytes and nitrites, and microscopy for red and white cells. Close agreement was shown for all laboratory analyses except proteinuria, which was underestimated by, on average, 10% after UCP passage. However, stick urinalysis for proteinuria remains sufficiently reliable for clinical use. UCP substantially retain or destroy red and white cells, but stick urinalysis for blood and leucocyte esterase remains reliable. In conclusion, urine samples derived from UCP show good agreement across a clinically relevant range for the biochemical analyses undertaken in this study. Microscopy of UCP samples is unreliable for cellular material but semi-quantitative stick urinalysis for red and white cells is a satisfactory alternative.     

Artificial attenuation of ECG voltage produces shortening of the corresponding QRS duration: clinical implications for patients with edema

BACKGROUND: Prolonged QRS duration (QRSd) is a useful index for the management of patients with congestive heart failure (CHF). QRSd is affected by changes in the ECG voltage (ECGV) in the context of development and amelioration of peripheral edema (PERE), independent of underlying pathology. Nowadays, physicians accept QRSd measured by computer techniques. The latter offers the possibility of testing the hypothesis that artificial alteration of the ECGV, simulating effects of PERE, could lead to changes in the QRSd. METHODS: To this end, voltage was attenuated by 25%, 50%, and 75% in 100 digital ECGs recorded from normal subjects and in 20 patients with complete left bundle branch block (LBBB), by merely increasing the calibration strength by 4/3, 2, and 4, respectively, and by using the same data. RESULTS: All ECGs were analyzed by the same computer program and this led to a reduction of global QRSd by 2.3 +/- 2.9%, 5.7 +/- 4.0%, and 11.9 +/- 6.2%, respectively, in the normal subjects, and 1.6 +/- 1.4%, 3.4 +/- 1.7%, and 8.2 +/- 3.6%, respectively, in the patients with LBBB. Correlation of the percent change in the global QRSd and the percent change in ECGV was good with an r = 0.65, and P = 0.00005 in the normal subjects, and an r = 0.74 and P = 0.00005 in the patients with LBBB. CONCLUSIONS: Apparent shortening in QRSd as a function of ECGV attenuation due to PERE could have implications in the follow-up of patients with CHF, and their selection for implantable cardioverter/defibrillators, or cardiac resynchronization therapy.     

Drug distribution during massing and its effect on dose uniformity in granules

Drug distribution during the initial stages of wet massing in a wet granulation process has been studied as a function of the relative solubility of the drug and the composition of the binder. The results of this initial wet massing process have been correlated with the drug distribution/granule size profile of the granulations.     

Chronic widespread pain and fibromyalgia: Should reports of increased mortality influence management?

There have been few studies examining whether persons with chronic widespread pain or fibromyalgia are at increased risk for dying prematurely. Among the studies conducted there is little consistency in results. If there is an increased mortality risk, it is of the order of a 30% excess and it may be related to the lifestyle of patients with these symptoms, including lack of exercise. Skilled judgment is required in determining whether reports of new symptoms are likely to indicate underlying new pathology. Studies are currently underway which will determine whether initial observations of an increased mortality risk can be replicated.     

Predictors of outcome for orofacial pain in the general population: a four-year follow-up study

Orofacial pain is often persistent, but it is not clear why it lasts in some patients but not in others. We aimed to describe the natural course of orofacial pain in a general population sample over a four-year period and to identify factors that would predict the persistence of pain. A cross-sectional population-based survey was conducted in the United Kingdom, involving 2504 participants (participation rate 74%), of whom 646 (26%) reported orofacial pain. Overall, 424 (79% adjusted participation rate) of these individuals participated at the four-year follow-up, of whom 229 (54%) reported orofacial pain and 195 (46%) did not report such pain. Persistent orofacial pain was associated with females, older age, psychological distress, widespread body pain, and taking medication for orofacial pain at baseline. These findings may have implications for the identification and treatment of patients with orofacial pain.     

Inequalities in infant mortality: trends by social class, registration status, mother's age and birthweight, England and Wales, 1976-2000

This article examines trends in inequalities in infant mortality in England and Wales between 1976 and 2000. It describes variations in neonatal, postneonatal and infant mortality by mother's age, registration status, father's social class, multiplicity and birthweight. Throughout the period, social class differences in mortality were wider in the postneonatal period than the neonatal period and there was considerable variation in infant mortality by age of mother, birthweight and multiplicity within both manual and non-manual groups.     

An improved urine collection pad method: a randomised clinical trial

Aim: To evaluate a modified urine collection pad (UCP) method for its ability to reduce heavy mixed growth bacterial contamination of UCP samples in young children with suspected urinary tract infection (UTI). Method: Febrile children under 2 years of age were randomised to two UCP methods: the same UCP kept in the nappy until urine was passed (single UCP group), or the UCP replaced with a fresh one every 30 minutes until urine was passed (replaced UCP group). In both groups a moisture sensitive audio alarm was used to signal passage of urine. Results: Eighty children were enrolled and a satisfactory sample was obtained in 68 (37 in the single UCP group and 31 in the replaced UCP group). In 12 children (15%), collection failed, mainly because of faecal soiling of the pad. UTI occurred in three children (4%). In the remaining 65 samples, heavy mixed growth (> 10⁵ organisms/ml) occurred in 1/31 (3%) in the replaced UCP group compared with 10/35 (29%) in the single UCP group (p  =  0.008). There were no adverse effects from the use of the moisture sensitive audio alarm. Conclusion: Changing the UCP every 30 minutes almost eliminates heavy mixed growth contamination of UCP samples and substantially increases the proportion of UCP results that confidently exclude UTI. This represents a simple and clinically important improvement to the UCP method which is reliable for diagnosing and excluding UTI in young children still in nappies. It has potential for use in outpatient clinics, in the primary healthcare setting, or at home.