Variation in recorded blood pressure terminal digit bias in general practice.

This study aims to identify the extent of terminal digit bias in routinely recorded blood pressures (BP) across a number of different general practices and report on changes in terminal digit bias over a 10-year period. It also explores the effect this may have had on the mean recorded BP in this population. BP records were taken from The Health Improvement Network database containing anonymized patient records from information entered by UK general practices in the financial years 1996-1997 to 2005-2006. The proportion of measurements ending in zero and the mean BP readings were calculated for each practice and for each year of data.Over this 10-year period the percentage of systolic BPs with zero terminal digits fell from 71.2 to 36.7% and mean recorded BP fell from 152.3 to 145.3 mm Hg. Correcting the BPs to remove terminal digit bias indicates a 2-3 mm Hg underestimation of the mean population systolic BP over this period. The between-practice variation in the percentage of zero terminal digit readings increased from 3.5 to 6.5 s.d. Although it is welcome to see a reduction in terminal digit bias, it is worrying to see the increase in variation between practices. There is evidence that terminal digit bias may lead to potential misclassification and inappropriate treatment of hypertensive patients. The increase in variation observed may therefore lead to an increased variation in the quality of care given to patients.

Estimating the proportion of young adults on antihypertensive treatment that have been correctly diagnosed.

This paper aims to identify how many young adults on antihypertensive treatment have been misclassified as hypertensive. We identified subjects aged under 35 on antihypertensive treatment, from the Health Surveys for England, 1998-2004. Pretreatment systolic and diastolic blood pressures were calculated by adjusting on-treatment blood pressures for the effects of treatment. Treatment effects were derived from meta-analysis. Subjects were classified as hypertensive if pretreatment blood pressure was >or=160/100 mm Hg, or was >or=140/90 mm Hg in conjunction with high cardiovascular risk. We then identified the proportion of treated subjects on antihypertensive treatment who were truly eligible for treatment. From the survey data we identified 65 adults (25 men and 40 women) under 35 on diuretics, beta-blockers, angiotensin converting enzyme inhibitors, calcium blockers or other antihypertensives. Average pretreatment blood pressure was 164/100 mm Hg in those eligible for treatment, and 136/79 mm Hg in those not eligible. The analysis indicated that 29.2% of adults aged 16-34 (95% confidence interval (CI): 18.6-41.8%) were truly eligible for antihypertensive treatment: 32.0% (95% CI: 14.9-53.5%) of men and 25.0% (95% CI: 12.7-41.2%) of women. A total of 73.7% (14 of 19) of subjects eligible and 41.3% (19 of 46) of subjects not eligible for treatment either had a body mass index >30 kg m(-2) or kidney disease (chi(2)-test P=0.018). Because of biological variation in blood pressure, most young adults on treatment for hypertension have been misclassified as hypertensive. Most who have been correctly diagnosed are either clinically obese or have kidney disease.

Factors affecting the uptake of cardiac rehabilitation services in a rural locality.

INTRODUCTION: A number of studies have investigated factors affecting uptake of cardiac rehabilitation services. However, little information on factors affecting uptake of services in rural localities is available. STUDY DESIGN: A cross-sectional survey. METHODS: A survey of patients eligible for cardiac rehabilitation was undertaken to investigate uptake of services. The effects of individual and geographic factors on service utilization were explored. RESULTS: Utilization rates for cardiac rehabilitation services within the South Staffordshire locality are low, with 59.3% of eligible patients invited to attend cardiac rehabilitation services following discharge from hospital, 38.6% attending and 22.5% completing the programme. Two factors were independently associated with low service utilization. Patients under the age of 65 years are 1.90 [95% confidence intervals (CI) 1.01-3.65] times more likely to complete rehabilitation than patients aged over 65 years, and women are only 0.48 (95% CI 0.22-1.03) times as likely as men to complete rehabilitation. The major reported barrier to utilization of services was access. This included problems with public transport, parking and the time and location of classes. Access and medical problems were significantly higher in older people and may have contributed to their low overall completion rate. Electoral ward deprivation, geographical access score, living in an urban or rural electoral ward, electoral ward of residence and provider were not significantly associated with service utilization. CONCLUSIONS: Overall, utilization rates were low. No geographical factors were associated with uptake of services, although the possible effect may have been mediated by the relative affluence of the locality. Two individual factors, age and sex, were most likely to influence uptake.

Chemical contamination of private drinking water supplies in the West Midlands, United Kingdom.

INTRODUCTION: In the United Kingdom, private drinking water supplies are subject to much less stringent sampling and testing regimes than are public supplies. Information regarding the quality of private drinking water supplies is disparate and poorly defined. The aim of this study was to collate the data for chemical contamination of private drinking water supplies in the West Midlands, a region of Central England with a population of 5.3 million. METHODS: The most recent year's data on the number of private supplies, the number of supplies sampled, and the number and type of failures for chemical parameters were obtained from District and Local Authorities in the West Midlands Region. RESULTS: Data covered 12-month periods during 1995-1996. Of the 6013 private supplies identified, samples from 1297 had been tested for chemical parameters during the period of the study. A total of 420 individual failures for chemical parameters were reported in 386 water supplies. The majority of breaches of United Kingdom and European Union standards were due to increased concentrations of nitrates (270), magnesium (21), manganese (17), and iron (15). Increased turbidity was present in 27 cases. Only 6 samples breached the standard for lead and 6 for pesticides. CONCLUSIONS: Over a quarter of the supplies tested during the period of the study were in breach of United Kingdom and European Union legislation. Of the reported failures, the high concentrations of nitrate and nitrite, lead, copper, and sulfate are of concern to health and remedial action is warranted. Regular sampling of private drinking water supplies remains necessary to prevent risk to health from a wide variety of toxic contaminants.