Are GP practice prescribing rates for coronary heart disease drugs equitable? A cross sectional analysis in four primary care trusts in England

STUDY OBJECTIVE

To analyse the associations between proxies of healthcare need and GP practice prescribing rates for five major coronary heart disease (CHD) drug groups.

DESIGN

Cross sectional secondary analysis.

SETTING

Four primary care trusts (PCTs 1-4) in the north west of England, encompassing 132 GP practices.

RESULTS

Prescribing rates were generally positively associated with the percentage of patients aged 55-74 years and PASS-PUs (regionally specific prevalence, age, and sex standardised prescribing units). However, the percentage of patients aged over 75 years showed a lack of association with prescribing rates in all PCTs other than PCT2. Correlations with the proportion of South Asian patients were generally negative, particularly in PCT2, PCT4, and the combined dataset. There was a general lack of association with deprivation proxies and SMRs for CHD, although there were negative associations with both variables in PCT4 and the combined dataset. Scatter plots showed that GP practices with similar prescribing rates had widely differing levels of comparative healthcare need, and GP practices with similar levels of healthcare need had widely differing prescribing rates.

CONCLUSION

GP prescribing rates in some PCTs were negatively associated with proxies of healthcare need based on patient age (patients aged over 75 years), ethnicity, levels of deprivation, and SMRs for CHD. As such, this study suggests that prescribing rates in these PCTs may be inequitable as they are not positively associated with healthcare need. This study may form the baseline for further studies to assess the effectiveness of the NSF for CHD in reducing the inequities in prescribing rates.

Clinical and economic choices in anaesthesia for day surgery: a prospective randomised controlled trial

We compared the cost-effectiveness of general anaesthetic agents in adult and paediatric day surgery populations. We randomly assigned 1063 adult and 322 paediatric elective patients to one of four (adult) or two (paediatric) anaesthesia groups. Total costs were calculated from individual patient resource use to 7 days post discharge. Incremental cost-effectiveness ratios were expressed as cost per episode of postoperative nausea and vomiting (PONV) avoided. In adults, variable secondary care costs were higher for propofol induction and propofol maintenance (propofol/propofol; p < 0.01) than other groups and lower in propofol induction and isoflurane maintenance (propofol/isoflurane; p < 0.01). In both studies, predischarge PONV was higher if sevoflurane/sevoflurane (p < 0.01) was used compared with use of propofol for induction. In both studies, there was no difference in postdischarge outcomes at Day 7. Sevoflurane/sevoflurane was more costly with higher PONV rates in both studies. In adults, the cost per extra episode of PONV avoided was pound 296 (propofol/propofol vs. propofol/ sevoflurane) and pound 333 (propofol/sevoflurane vs. propofol/isoflurane).

Propofol and halothane versus sevoflurane in paediatric day-case surgery: induction and recovery characteristics

BACKGROUND

The aim of this study was to compare the induction and recovery characteristics associated with propofol induction and halothane maintenance with sevoflurane anaesthesia in paediatric day surgery.

METHODS

In total, 322 children were assigned randomly to i.v. propofol induction and halothane/nitrous oxide maintenance or sevoflurane/nitrous oxide alone. The patients' age, sex, and type of surgery were recorded, as were the times required for anaesthetic induction, maintenance, recovery and time to discharge home. Postoperative nausea and vomiting, and the incidence of adverse events during induction and recovery were also noted.

RESULTS

No significant differences were detected in age, sex, type of surgery performed or intraoperative opioid administration. Excitatory movement was more common during induction with sevoflurane. The mean time required for induction with propofol was 3.1 min compared with 5 min in the sevoflurane group (P<0.001). The recovery time was shorter in the sevoflurane group compared with propofol/halothane (23.2 vs 26.4 min, P<0.002). The incidence of delirium in recovery was greater in the sevoflurane group (P<0.001). There was no difference between groups in the time spent on the postoperative ward before discharge home. On the postoperative ward the incidence of both nausea and vomiting was significantly higher in the sevoflurane group (P=0.034). Five children were admitted to hospital overnight, none for anaesthetic reasons.

CONCLUSIONS

The increased incidence of adverse events during induction, postoperative nausea and vomiting and postoperative delirium in the sevoflurane group suggests that sevoflurane is not ideal as a sole agent for paediatric day case anaesthesia.

Developing prevalence-based prescribing units for analysing variations in general practitioner prescribing: a case study using statins

OBJECTIVE

To develop regionally specific prevalence-, age- and sex-standardized prescribing units (PASS-PUs) and to relate these to statin prescribing.

DESIGN

Cross-sectional.

SETTING

Ninety-four general practitioner (GP) practices within one health authority in the north-west of England.

MAIN OUTCOME MEASURES

Comparisons between specific therapeutic group age-sex-related prescribing units (STAR-PUs) and PASS-PUs for statin prescribing.

RESULTS

STAR-PUs and PASS-PUs were calculated for all GP practices and there was a high degree of correlation (Spearman's rank coefficient 0.88; P < 0.001). Using actual prescribing data for statins for a 12-month period, a statistically significant correlation was found between net ingredient cost per patient and STAR-PUs per patient (Spearman's rank coefficient 0.36; P < 0.01). However, the correlation between average daily quantities per patient and PASS-PUs per patient was not statistically significant. A scatter plot revealed a pattern whereby GP practices with high proportions of patients aged over 75 years exhibited low statin prescribing in relation to the expected prevalence of treated coronary heart disease (CHD) in their patient population.

CONCLUSIONS

Low weightings for patients aged over 75 years in calculating STAR-PUs lead to a much lower number of prescribing units within GP practice populations when compared with PASS-PUs. Current statin prescribing across GP practices in this study correlates with national prescribing cost patterns (as measured by STAR-PUs) although not with expected prevalence of treated CHD (as measured by PASS-PUs). PASS-PUs reflect prevalence of treated CHD and may therefore be used to monitor and predict GP prescribing arising from the implementation of the National Service Framework targets for CHD. In addition, PASS-PUs maybe derived for a wide range of therapeutic areas.

Screening for cognitive impairment in older African-Caribbeans

BACKGROUND

There are increasing numbers of older African-Caribbeans in the United Kingdom. Screening instruments are commonly used in the detection of cognitive impairment, but have not been assessed within this population. This study aimed to develop culturally modified versions of screening instruments for cognitive impairment (Mini-Mental State Examination (MMSE) and Abbreviated Mental Test (AMT)) and to determine their sensitivity and specificity in the diagnosis of dementia.

METHODS

The instruments were modified using a process involving a community group of African-Caribbeans and an academic group of health professionals. They were used in a two-stage study involving community resident African-Caribbeans aged 60 years or over in inner-city Manchester, comparing the screening instruments against a computerized diagnostic interview.

RESULTS

One hundred and thirty people completed the study. The results for the largest subgroup, the Jamaicans (N = 96) were analysed. Effects of gender, age and education on the MMSE and AMT scores were evaluated. The correlations between the screening instruments and diagnostic interview were highly significant (P < 0.001). At appropriate cut-offs both screening instruments demonstrated high sensitivity and acceptable specificity levels.

CONCLUSIONS

A defined process with lay input has assisted in producing culturally modified versions of the MMSE and AMT that perform well compared with a diagnostic interview, if an appropriate cut-off is used. They are easy to administer and acceptable to older African-Caribbean people. The results need to be viewed within the limitations of the current study.

Interventions to increase breast screening uptake: do they make any difference?

BACKGROUND

Breast screening has an important role in improving survival from breast cancer through early detection and treatment. Increasing uptake of screening in areas of low uptake is important in improving the effectiveness of the national screening programme. This review looks at which initiatives to boost uptake have been successful.

OBJECTIVE

To evaluate the effectiveness of the different interventions to increase breast screening uptake.

METHOD

A systematic review of interventions to promote breast screening uptake was undertaken. Studies were included if uptake was used as an outcome measure of the intervention and if relevant to the UK screening programme.

RESULTS

Twenty eight studies were found among 25 citations. Interventions were grouped into "person directed", "system directed", "social network directed", and "multistrategy" categories. Most were person directed. These interventions were more likely to be effective in boosting uptake, be simple in design, and to have been evaluated by a randomized trial design. Evidence of effectiveness in the other groups is limited both by the number of studies and the study designs. A summary of the interventions reviewed is presented.

CONCLUSIONS

Simple, brief, and effective interventions exist to boost breast screening uptake. More complicated approaches are not necessarily any more effective. These findings also have implications for other population based screening programmes of the future. In inner city areas the best approach to raising uptake rates is likely to be multistrategy.

Validating screening instruments for cognitive impairment in older South Asians in the United Kingdom

BACKGROUND

The numbers of older South Asians in the United Kingdom are rising. Investigation of their mental health has been neglected compared to their physical health.

OBJECTIVES

This study aimed to determine the sensitivity and specificity of modified versions of two screening instruments for cognitive impairment (Mini-Mental State Examination and Abbreviated Mental Test) in a community-based population.

DESIGN

Two-stage study comparing screening instruments against diagnostic interview.

SETTING

South, central and north Manchester.

SUBJECTS

Community-resident South Asians aged 60 years and over.

METHODS

Subjects were approached via their general practitioners and interviewed at home. Sensitivity and specificity for the screening instruments were calculated using receiver operating characteristic (ROC) curve analysis.

RESULTS

For the Gujarati population, the MMSE cutoff was >/=24 (sensitivity 100%, specificity 95%) and AMT>/=6 (sensitivity 100%, specificity 95%). For the Pakistani population, the MMSE cutoff was >/=27 (sensitivity 100%, specificity 77%) and AMT>/=7 (sensitivity 100%, specificity 87%).

CONCLUSIONS

Culturally modified versions of the Mini-Mental State Examination and Abbreviated Mental Test are acceptable and may have a high degree of sensitivity. They may assist with the recognition of cognitive impairment, if an appropriate cutoff is used.

Screening for depression in African-Caribbean elders

BACKGROUND

There are increasing numbers of older African-Caribbeans in the UK. Primary care staff often feel less confident about diagnosing depression in this group. Screening instruments may assist in making diagnoses in cross-cultural consultations.

OBJECTIVE

We aimed to determine the sensitivity and specificity of screening instruments for depression in older African-Caribbean people in Manchester, UK.

METHODS

We carried out a two-stage study to compare three screening instruments for depression (Geriatric Depression Scale, Brief Assessment Schedule Depression Cards, Caribbean Culture Specific Screen), with a computerized diagnostic interview for mental health disorders in older adults (Geriatric Mental State). The study was set in inner-city Manchester. The subjects were community-resident African-Caribbeans aged 60 years and over; 227 subjects were approached. Of the 160 people screened, 130 agreed to diagnostic interview. The main outcome measures were Spearman correlation coefficients; these were calculated between each screening instrument and the diagnostic interview. Receiver-operating characteristic (ROC) curve analysis was used to determine appropriate sensitivity and specificity for each instrument.

RESULTS

The results for the largest subgroup, the Jamaicans (n = 96/130), demonstrated highly significant correlations between screening instruments and diagnostic interview (P < 0.001). Each instrument had a high sensitivity: Brief Assessment Schedule depression cards (cut-off > or =6; sensitivity 90.9% (95% CI 58.8-99.8), specificity 82.1% (95% CI 74.0-90.3)), Caribbean Culture Specific Screen (cut-off > or =6; sensitivity 90.9% (95% CI 58.8-99.8), specificity 74.1% (95% CI 64.8-83.4)), and Geriatric Depression Scale (cut-off > or =4; sensitivity 100% (95% CI 97.1-100), specificity 69.1% (95% CI 59.6-79.2)).

CONCLUSIONS

These screening instruments demonstrate high sensitivity levels, if an appropriate cut-off point is used. The culture-specific instrument did not perform better than the traditional instruments. Health professionals should approach the consultation in a culturally sensitive manner and use the validated instrument they are most familiar with.

Screening for abdominal aortic aneurysm: a computer assisted cost-utility analysis

OBJECTIVES

To evaluate the effects of introducing routine ultrasonic screening for the identification and elective surgical treatment of abdominal aortic aneurysms (AAA) at high risk of rupture in the U.K. population of men aged 65-74 years.

DESIGN

A computer assisted simulation of an AAA screening programme. The simulation incorporated assumptions gleaned from the literature about the epidemiology of AAA and the costs of screening. In addition, up-to-date costings based on recent Manchester (U.K.) vascular surgery experience are used.

SETTING

A dialogue between National Health Service commissioners and providers to explore the feasibility and desirability of introducing AAA screening. CHIEF OUTCOME MEASURE: Cost per quality adjusted life year (QALY) gained.

MAIN RESULTS

The absolute cost (circa 1992/3) per QALY gained from screening for and treating aneurysms of > or = 6 cm in diameter of pounds 1500 (benefit not discounted). Offsetting current treatment costs of ruptured aneurysms gives a net additional cost per QALY of pounds 1300. Screening and treating aneurysms of > or = 5 cm leads to a cost per QALY gained exceeding pounds 20000. The findings are robust under sensitivity analysis.

CONCLUSIONS

Routine screening for AAAs of size > or = 6 cm compares favourably in terms of cost per QALY gained with services such as breast and cervical cancer screening.

Hearing aids: value for money and health gain

BACKGROUND

The aim of this study was to assess the ability of hearing aids to reduce the handicap associated with hearing impairment in adults.

METHODS

Fifty adults aged over 60 who were supplied with an NHS hearing aid had their hearing handicap and communication function recorded at initial hearing aid assessment, and after three months of aid use. Hearing communication function was assessed by a key informant.

RESULTS

Hearing aid use was associated with considerable score improvements for social and emotional function [20.5, 95 per cent confidence interval (Cl) 15.4-25.6] and communication function (22.9, 95 percent Cl 14.6-31.2). Younger people recorded the greatest reduction in handicap. Overall satisfaction with hearing aid performance was high.

CONCLUSIONS

Hearing aids are effective in reducing hearing handicap in adults. They represent a good buy for purchasers seeking to achieve health gain for adults with hearing impairment.

Response by women aged 65-79 to invitation for screening for breast cancer by mammography: a pilot study

OBJECTIVE

To determine whether there is sufficient benefit to be gained by offering screening for breast cancer with mammography to women aged 65-79, who are not normally invited for screening.

DESIGN

Pilot study of women eligible for screening but not for personal invitation. The results of this study were compared with the results of routinely screened younger women (aged 50-64) from the same general practice.

SETTING

One group general practice in south Manchester.

PATIENTS

The 631 women aged 65-79 on the practice list. A total of 42 (7%) were excluded by the general practitioner, and 22 (4%) invitation letters were returned by the post office.

MAIN OUTCOME MEASURES

Response rates to invitation for screening assessed by three indices: crude population coverage ratio, crude invited population coverage ratio, and corrected invited population coverage ratio.

RESULTS

344 Patients aged 65-79 (61% of those invited, excluding those who could not be traced) were screened compared with 77% of women aged 50-64. The three response indices were higher for younger women than older: crude population coverage ratio = 66.5%, crude invited population coverage ratio = 69.3%, corrected invited population coverage ratio = 76.8% for women aged 50-64, compared with 54.5%, 58.4%, and 60.7% respectively for women aged 65-79. All four biopsies done in the older women gave positive results, giving a cancer detection rate of 11.6/1000 compared with 4.1/1000 among younger women.

CONCLUSIONS

These results show that there is a potential for high attendance at routine screening by older women if they are invited in the same way as younger women. If these results are found elsewhere the costs and benefits of screening older women should be reassessed.

Would a healthier population consume fewer health service resources? A life-table analysis using hospital in-patient enquiry (HIPE) bed-usage statistics as a proxy for hospital treatment costs

The long-term effects upon acute-care hospital costs of reductions of morbidity and mortality from various causes are explored. The daily number of beds used per million population for all diagnostic categories is suggested as a proxy measure of hospital costs. An index of lifetime bed usage for a hypothetical cohort of persons living out their lives under specified age-specific mortality and morbidity patterns is derived. Examples of the application of this index are given for differing assumptions about mortality and morbidity in males. It is shown that reducing ischaemic heart disease or cancer morbidity will lead to increased overall hospital costs whereas reductions in the rate of occurrence of accidents, injuries and poisonings would reduce overall costs. The assumptions underlying the use of the index are discussed and extensions to the population model are proposed.

Analysis of secular trends in surgery for glue ear in the North Western Region (1975-1984)

Hospital Activity Analysis (HAA) data relating to operations for glue ear and tonsillectomy performed on residents of the North Western Region, aged 0-9 years during the period 1975-1984 were studied. The rate of surgery for glue ear has risen from 45/10,000 to 107/10,000 representing an increase of 137 per cent. The tonsillectomy rate by comparison has undergone a more modest increase of 19 per cent. The study casts doubt on a 'vacuum effect', as has been argued by Black. Marked variation in rates of surgery between Districts in the Region were noted, and the possible explanations discussed. A review of the literature revealed considerable controversy concerning the management of glue ear and the need for a definitive trial is highlighted.

A randomised controlled trial of the effect of low fat diet advice on dietary response in insulin independent diabetic women

Type 2 (insulin independent) diabetic women were randomly allocated to receive advice for low fat diets or low carbohydrate diets. By 24 h weighted dietary intakes before and after a mean interval of six months, patients in the low fat group had reduced their fat intake from 41% to 31% of total energy, while carbohydrate percentage of total energy intake increased from 38% to 46%. Percentage energy intake from fat and carbohydrate in the control group remained unchanged. Body weight fell in both groups especially for patients in the low fat group who were obese (weight/height2 greater than or equal to 28 kg/m2). Mean plasma glucose, HbA1, and triglycerides were unchanged. Mean plasma total cholesterol fell significantly in the low fat group compared with the controls (p less than 0.001), but there was no significant difference in the small reduction of high density lipoprotein cholesterol observed in both groups. Thus, adherence to low fat diets occurred without deterioration of diabetes and with benefit for weight and total cholesterol.

Plasma cholesterol and blood pressure in vegetarians

Plasma cholesterol, high-density lipoprotein cholesterol (HDL) and blood pressure were examined in three hundred subjects with a special interest in 'health foods'. The 85 vegetarians showed on average a lower total cholesterol and higher HDL per cent than the 214 non-vegetarians. The vegetarians were also leaner than the non-vegetarians in each age group in both sexes. No consistent differences were found in blood pressure. The vegetarians took more dietary fibre than the non-vegetarians and the possibility that this may be relevant to the other differences found will be examined further.

Respiratory infections and their influence on lung function in children: a multiple regression analysis

The relationship between a history of respiratory infections (and associated variables) in children and lung function in later life was examined in a study among 228 children aged 7 to 11 years. In a multiple regression analysis only a few variables showed marked and consistent effects on lung function. Respiratory tract infections showed increasing impairment of lung function with repeated infections, but the impairment was smaller than that caused by current asthma.

Respiratory morbidity and lung function in schoolchildren aged 7 to 11 years in South Wales and the West of England

The present study tests the suggestion that the respiratory morbidity of children resident in South Wales is substantially higher than that among children resident in some other areas of the United Kingdom. A case control survey was carried out among 2228 children aged 7 to 11 years in schools matched for size and socioeconomic characteristics in urban and rural areas in South Wales and the West of England. The survey confirmed that respiratory morbidity was higher among children in South Wales and that this excess could not readily be dismissed as being caused by over-reporting. However, objective measurements of the children's respiratory health did not detect any consistent difference in the lung function of children in South Wales compared with that of children in the West of England.

Appendicectomy and dietary fibre

The hypothesis that dietary fibre protects against appendicitis was tested. One thousand seven hundred subjects, involved in another enquiry, were sent a questionnaire asking about their intake of cereal fibre and other foodstuffs, and whether or not they had had an appendectomy. The respondents, who represented 92 per cent of the sample, were divided into those who ate wholemeal bread daily and those who ate wholemeal bread rarely or never. These groups appeared to be very similar with respect to age, sex, smoking habit, alcohol intake and various other factors. Comparison of appendicectomy rates between those who ate wholemeal bread and those who did not showed a deficit among the former, which is consistent with a protective effect of cereal fibre, but the difference was not statistically significant.

Effects of anti-mite measures on children with mite-sensitive asthma: a controlled trial

Mite counts and tests for mite antigen were performed on samples of dust taken from the bedding of 53 children with mite-sensitive asthma. The samples from damp houses and the beds or enuretic children had markedly more mites and mite-antigen than those from dry houses. although the predominant species was usually Dermatophagoides pteronyssinus, some of the beds in the damp houses were heavily infested with another pyroglyphid mite Euroglyphus maynei, so that this was the species found in the greatest numbers. D pteronyssinus antigen was found to be correlated broadly with the total mite count, but more antigen was present for a given number of mites in the mattresses than in the blankets. The children were randomly allocated into two groups, one of which carried out rigorous anti-mite measures. The amounts of dust and mite antigen were reduced, though not the numbers of mites. Peak flow readings were monitored in the two groups for eight weeks and a final assessment made by a paediatrician who was unaware of the allocation of each patient in the trial. No significant differences emerged in the progress of the two groups, both tending to improve. Measures designed to remove mites from bedding do not greatly benefit the majority of children with mite-sensitive asthma.

Vitamin C, high density lipoproteins and heart disease in elderly subjects

Plasma vitamin C, total and high density lipoprotein (HDL) cholesterol and cortisol levels were measured in a random sample of 337 elderly subjects living at home in S. Wales; measurements of relative body weight and information about fruit intake, smoking habits and symptoms of cardiovascular disease were also collected. There was a sex difference, over all age groups, in plasma vitamin C and in total HDL cholesterol levels. Plasma vitamin C was strongly correlated with fruit intake in both sexes. Both HDL cholesterol and low and very density lipoprotein (LDL + VLDL) cholesterol levels tended to increase with increasing plasma vitamin C but this reached significance only for the LDL + VLDL fraction. In addition, HDL cholesterol was negatively correlated with Quetelet's index in the women. Symptoms and medication for heart disease did not correlate significantly with plasma vitamin C or with HDL cholesterol levels, but reported angina showed a weak positive association with total cholesterol in the men, and there was some evidence of increased cortisol levels in subjects with heart disease.

Factors associated with cardiac mortality in developed countries with particular reference to the consumption of wine

Deaths from ischaemic heart-disease in 18 developed countries are not strongly associated with health-service factors such as doctor and nurse density. There is a negative association with gross national product per capita and a positive but inconsistent association with saturated and monounsaturated fat intake. The principal finding is a strong and specific negative association between ischaemic heart-disease deaths and alcohol consumption. This is shown to be wholly attributable to wine consumption.

The prevalence, severity and factors associated with urinary incontinence in a random sample of the elderly

A study to determine the prevalence of urinary incontinence in a random sample of a total elderly community is described. The prevalence of incontinence in women aged 65 years or more was found to be 17% and in men 11%. The findings show that the prevalence of incontinence is particularly high among residents of old people's homes and geriatric hospitals, but that the majority of cases occur within the general community. The prevalence increases with age in both sexes; associations with a history of cerebrovascular disease, certain surgical procedures, multiple hospital admissions and drug usage are described. The findings of a follow-up study suggest that, although the disorder is long-standing and severe in a proportion of subjects, it is transient in approximately a third of all elderly subjects with the condition.

Statistical problems in studying the relative specificities of association between environmental agents and different diseases: a solution suggested

If an environmental agent is strongly associated with only one disease then that is greater evidence in favour of a casual relationship than if that agent were also strongly associated with other unrelated diseases. Standard regression and correlation analysis are shown to be incapable of answering questions about disease specificity. A simple index, based upon regression, is proposed. The standardised regression coefficients in a regression equation based on the logistic transformation of a death rate are shown to have a particularly simple interpretation in terms of our index. The work is illustrated on an example drawn from the controversy concerning the association between area differences in ischaemic heart disease mortality and water hardness.

Health service 'input' and mortality 'output' in developed countries

The relationship between age-specific mortality rates and some indices of health facilities and some environmental and dietary factors has been studied in 18 developed couuntries. The indices of health care are not negatively associated with mortality, and there is a marked positive association between the prevalence of doctors and mortality in the younger age groups. No explanation of this doctor anomaly has so far been found. Gross national product per head is the principal variable which shows a consistently strong negative association with mortality.

Housing conditions, respiratory illness, and lung function in children in South Wales

The hypothesis was tested that respiratory illness in children occurs more commonly in old housing than in housing built to modern standards. Three areas of housing were chosen in a South Wales valley: a recently constructed council estate with district central heating; a modern council estate heated with open coal fires; and an area of much older, traditional valley housing. Mothers reported the greatest proportion of children free of colds and sore throats during the previous 12 months in the area of traditional valley housing; mothers of children in the centrally heated estate reported the least proportion of children free of colds. Children's lung function was best in the area of traditional valley housing and worst in the centrally heated council estate. Data on demographic indices and respiratory morbidity suggest that the inhabitants of the two council estates have comparable characteristics. Another hypothesis which may explain the findings is proposed.

A randomized controlled trial of vitamin C in the prevention and amelioration of the common cold

A randomized controlled trial of the effect of 1 g ascorbic acid per day in the prevention of the common cold was conducted on 688 adult women. There is evidence of a small reduction by vitamin C in the mean number of chest colds, but no evidence of any effect on simple colds. The existence of a subgroup of vulnerable women in the community who benefit from vitamin C was considered but further examination of the data gives no support to this conclusion.

Anti-mite measurements in mite-sensitive adult asthma. A controlled trial

A cross-over controlled trial has been conducted among 32 adult patients with mite-sensitive asthma. The bedclothes and pillows of each subject were laundered and vacuum-cleaned and a plastic cover applied to the mattress for six weeks in an attempt to reduce exposure to mites. No improvement in daily peak-flow reading or drug usage was found in comparison with a control period.

A community survey of asthmatic characteristics

A survey was undertaken among adults aged 20-44 years in a South Wales town. Persons with a history of wheezing with breathlessness and in the absence of a cold were identified by postal questionnaires and seen at a clinic, together with a sample of subjects without these symptoms. The response rates for the first and second stages of the survey were 99.6% and 91.0% respectively, and 574 subjects were ultimately seen. Asthmatic patients (those receiving treatment within the previous year) had some airways obstruction at rest, which increased after exercise. They also had strong allergic tendencies, as shown by personal and family history, skin tests, and serum IgE levels. The ex-asthmatics (those not receiving treatment within the previous year) showed these tendencies to a lesser extent. A larger group gave a history of wheezing but stated that they had never had asthma; in their response to exercise and allergic traits they resembled the control group rather than the asthmatics, and appeared to have the features of chronic bronchitis. Asthma and chronic bronchitis would therefore seem to be distinct entities within the population studied.