Cumulative flying time and risk of venous thromboembolism.

The risk of venous thromboembolism (VTE) associated with cumulative flying time remains uncertain. In a case-control study in general practices throughout the UK, participants comprised 550 VTE cases identified from practice records and 1971 age- and gender-matched controls. Participants returned identical questionnaires asking for information including air travel details. Compared to not flying, cumulative flying time >12 h within the previous 4 weeks was associated with a threefold increase in the risk of VTE [odds ratio (OR) 2·75, 95% confidence interval (CI), 1·44-5·28]. Those who had flown >4 h in a single leg in the previous 4 weeks had twice the risk of VTE (OR 2·20, 95% CI, 1·29-3·73). These risks were no longer evident by 12 weeks and were similar to those of day-case or minor surgery (OR 5·35, 95% CI, 2·15-13·33). Equivalent risks for moderate and high-risk surgery were over 30-fold (OR 36·57, 95% CI, 13·05-102·52) and 140-fold (OR 141·71, 95% CI, 19·38-1036·01) respectively. The temporary nature of the association of cumulative and long-haul air travel with VTE suggests a causal relationship. The risks of VTE in those with a higher baseline risk due to surgery, previous VTE or obesity are further increased by air travel.

Control of exposure to mite allergen and allergen-impermeable bed covers for adults with asthma.

BACKGROUND: The effectiveness of avoidance of house-dust-mite allergen (Dermatophagoides pteronyssinus 1 [Der p1]) in the management of asthma is uncertain. METHODS: We conducted a double-blind, randomized, placebo-controlled study of allergen-impermeable bed covers involving 1122 adults with asthma. The primary outcomes were the mean morning peak expiratory flow rate over a four-week period during the run-in phase and at six months and the proportion of patients who discontinued inhaled corticosteroid therapy as part of a phased-reduction program during months 7 through 12. Der p1 was measured in mattress dust in a 10 percent random subsample of homes at entry and at 6 and 12 months. RESULTS: The prevalence of sensitivity to dust-mite allergen was 65.4 percent in the group supplied with allergen-impermeable bed covers (active-intervention group) and 65.1 percent in the control group supplied with non-impermeable bed covers. The concentration of Der p1 in mattress dust was significantly lower in the active-intervention group at 6 months (geometric mean, 0.58 microg per gram vs. 1.71 microg per gram in the control group; P=0.01) but not at 12 months (1.05 microg per gram vs. 1.64 microg per gram; P=0.74). The mean morning peak expiratory flow rate improved significantly in both groups (from 410.7 to 419.1 liters per minute in the active-intervention group, P<0.001 for the change; and from 417.8 to 427.4 liters per minute in the control group, P<0.001 for the change). After adjustment for base-line differences (by analysis of covariance), there was no significant difference between the groups in the peak expiratory flow rate at six months (difference in means, active-intervention group vs. control group, -1.6 liters per minute [95 percent confidence interval, -5.9 to 2.7] among all patients [P=0.46] and -1.5 liters per minute [95 percent confidence interval, -6.9 to 3.9] among mite-sensitive patients [P=0.59]). There was no significant difference between the groups in the proportion in whom complete cessation of inhaled corticosteroid therapy was achieved (17.4 percent in the active-intervention group and 17.1 percent in the control group) or in the mean reduction in steroid dose, either among all patients or among mite-sensitive patients. CONCLUSIONS: Allergen-impermeable covers, as a single intervention for the avoidance of exposure to dust-mite allergen, seem clinically ineffective in adults with asthma.

The Women's international study of long-duration oestrogen after menopause (WISDOM): a randomised controlled trial.

BACKGROUND: At the time of feasibility work and final design of the trial there was no randomised control trial evidence for the long-term risks and benefits of hormone replacement therapy. Observational studies had suggested that long term use of estrogen was likely to be associated, amongst other things, with reduced risks of osteoporosis and ischaemic heart disease and increased risks of breast and endometrial cancer. Concomitant use of progestogens had been shown to protect against endometrial cancer, but there were few data showing how progestogen might affect estrogen actions on other conditions. Disease specific risks from observational studies suggested that, overall, long-term HRT was likely to be beneficial. Several studies showed that mortality from all causes was lower in HRT users than in non-users. Some secondary cardiovascular prevention trials were ongoing but evidence was also required for a range of outcomes in healthy women. The WISDOM trial was designed to compare combined estrogen and progestogen versus placebo, and estrogen alone versus combined estrogen and progestogen. During the development of WISDOM the Women's Health Initiative trial was designed, funded and started in the US. DESIGN: Randomised, placebo, controlled, trial. METHODS: The trial was set in general practices in the UK (384), Australia (94), and New Zealand (24). In these practices 284175 women aged 50-69 years were registered with 226282 potentially eligible. We sought to randomise 22300 postmenopausal women aged 50 - 69 and treat for ten years. The interventions were: conjugated equine estrogens, 0.625 mg orally daily; conjugated equine estrogens plus medroxyprogesterone acetate 2.5/5.0 mg orally daily; matched placebo. Primary outcome measures were: major cardiovascular disease, osteoporotic fractures, breast cancer and dementia. Secondary outcomes were: other cancers, all cause death, venous thromboembolism and cerebro-vascular disease. RESULTS: The trial was prematurely closed during recruitment following publication of early results from the Women's Health Initiative. At the time of closure, 56583 had been screened, 8980 entered run-in, and 5694 (26% of target of 22,300) randomised. Those women randomised had received a mean of one year of therapy, mean age was 62.8 years and total follow-up time was 6491 person years. DISCUSSION: The WISDOM experience leads to some simple messages. The larger a trial is the more simple it needs to be to ensure cost effective and timely delivery. When a trial is very costly and beyond the resources of one country, funders and investigators should make every effort to develop international collaboration with joint funding.

A randomised controlled trial investigating the effect of n-3 long-chain polyunsaturated fatty acid supplementation on cognitive and retinal function in cognitively healthy older people: the Older People And n-3 Long-chain polyunsaturated fatty acids (OPAL) study protocol [ISRCTN72331636].

The number of individuals with age-related cognitive impairment is rising dramatically in the UK and globally. There is considerable interest in the general hypothesis that improving the diet of older people may slow the progression of cognitive decline. To date, there has been little attention given to the possible protective role of n-3 long-chain polyunsaturated fatty acids (n-3 LCPs) most commonly found in oily fish, in age-related loss of cognitive function. The main research hypothesis of this study is that an increased dietary intake of n-3 LCPs will have a positive effect on cognitive performance in older people in the UK. To test this hypothesis, a double-blind randomised placebo-controlled trial will be carried out among adults aged 70-79 years in which the intervention arm will receive daily capsules containing n-3 LCP (0.5 g/day docosahexaenoic acid and 0.2 g/day eicosapentaenoic acid) while the placebo arm will receive daily capsules containing olive oil. The main outcome variable assessed at 24 months will be cognitive performance and a second major outcome variable will be retinal function. Retinal function tests are included as the retina is a specifically differentiated neural tissue and therefore represents an accessible window into the functioning of the brain. The overall purpose of this public-health research is to help define a simple and effective dietary intervention aimed at maintaining cognitive and retinal function in later life. This will be the first trial of its kind aiming to slow the decline of cognitive and retinal function in older people by increasing daily dietary intake of n-3 LCPs. The link between cognitive ability, visual function and quality of life among older people suggests that this novel line of research may have considerable public health importance.

Population-based multidimensional assessment of older people in UK general practice: a cluster-randomised factorial trial.

BACKGROUND: The benefit of multidimensional assessment and management of older people remains controversial. Most trials have been too small to produce adequate evidence to inform policy. We aimed to measure the effects of different approaches to assessment and management of older people. METHODS: We undertook a cluster-randomised factorial trial in 106 general practices (43219 eligible patients aged 75 years and older, 78% participation), comparing (1) universal versus targeted assessment and (2) subsequent management by hospital outpatient geriatric team versus the primary-care team. All participants received a brief multidimensional assessment followed by a nurse-led in-depth assessment in the universal group, whereas in the targeted group the in-depth assessment was offered only to those with problems established at the brief assessment. Referrals to the randomised team (geriatric management or primary care), other medical or social services, health-care workers, or agencies, and emergency referrals to the general practitioner were based on a standard protocol at the in-depth assessment. The primary endpoints were mortality, admissions to hospital and institution, and quality of life. Analysis was by intention to treat and per protocol. This trial has been assigned the International Standardised Randomised Controlled Trial Number ISRCTN23494848. FINDINGS: Mortality and hospital or institutional admissions did not differ between groups. During 3 years' follow-up, significant improvements in quality of life resulted from universal versus targeted assessment in terms of homecare, and from management by geriatric team versus primary-care team, in terms of mobility, social interaction, and morale. However, only the result for social interaction was consistent with a small but important effect. INTERPRETATION: The different forms of multidimensional assessment offered almost no differences in patient outcome.

The management of newly identified asthma in primary care in England.

AIMS: To establish by case note review how people with newly diagnosed asthma were treated in general practice. METHODS: A retrospective cross-sectional survey was carried out in twelve general practices from the MRC General Practice Research Framework. Children between their 3rd and 8th birthdays and adults 16 years and over were identified with newly diagnosed or treated asthma from computer records with further details obtained from a case record search. The main outcome measure was the time of recorded asthma diagnosis and the time of first prescriptions for inhaled corticosteroids. RESULTS: For 41% of children and 53% of adults with a diagnosis of asthma and inhaled corticosteroids, inhaled corticosteroids were prescribed before or on the same day as the diagnosis of asthma was recorded. Diagnosis tended to be made on the basis of a patient's medical history with fewer than 20% of patients having results of any tests recorded in their medical notes. The time from first respiratory consultation to inhaled corticosteroid prescription was statistically significantly shorter in those children for whom a diagnosis of asthma was recorded (p=0.038) compared to those children without a recorded diagnosis of asthma. CONCLUSIONS: Inhaled corticosteroids are frequently prescribed before a diagnosis of asthma is recorded. A diagnostic label of asthma in children significantly reduces the length of time from the date of first respiratory consultation to inhaled corticosteroid prescription. If inhaled corticosteroids are to be prescribed early there must be an improvement in the diagnosis of asthma in primary care, including the recording of results in patient's medical notes.

Advice to use topical or oral ibuprofen for chronic knee pain in older people: randomised controlled trial and patient preference study.

OBJECTIVE: To determine whether older patients with chronic knee pain should be advised to use topical or oral non-steroidal anti-inflammatory drugs (NSAIDs). DESIGN: Randomised controlled trial and patient preference study. SETTING: 26 general practices. PARTICIPANTS: People aged > or =50 with knee pain: 282 in randomised trial and 303 in preference study. INTERVENTIONS: Advice to use topical or oral ibuprofen. Primary outcome measures WOMAC (Western Ontario and McMaster Universities) osteoarthritis index, major and minor adverse effects. RESULTS: Changes in global WOMAC scores at 12 months were equivalent. In the randomised trial the difference (topical minus oral) was two points (95% confidence interval -2 to 6); in the preference study, it was one point (-4 to 6). There were no differences in major adverse effects in the trial or study. The only significant differences in secondary outcomes were in the randomised trial. The oral group had more respiratory adverse effects (17% v 7%,95% confidence interval for difference -17% to -2%), the change in serum creatinine was 3.7 mmol/l less favourable (0.9 micromol/l to 6.5 micromol/l); and more participants changed treatments because of adverse effects (16% v 1%, -16% to -5%). In the topical group more participants had chronic pain grade III or IV at three months, and more participants changed treatment because of ineffectiveness. CONCLUSIONS: Advice to use oral or topical preparations has an equivalent effect on knee pain over one year, and there are more minor side effects with oral NSAIDs. Topical NSAIDs may be a useful alternative to oral NSAIDs. TRIAL REGISTRATION: ISRCTN 79353052.

Health related quality of life after combined hormone replacement therapy: randomised controlled trial.

OBJECTIVE: To assess the effect of combined hormone replacement therapy (HRT) on health related quality of life. DESIGN: Randomised placebo controlled double blind trial. SETTING: General practices in United Kingdom (384), Australia (94), and New Zealand (24). PARTICIPANTS: Postmenopausal women aged 50-69 at randomisation; 3721 women with a uterus were randomised to combined oestrogen and progestogen (n=1862) or placebo (n=1859). Data on health related quality of life at one year were available from 1043 and 1087 women, respectively. INTERVENTIONS: Conjugated equine oestrogen 0.625 mg plus medroxyprogesterone acetate 2.5/5.0 mg or matched placebo orally daily for one year. MAIN OUTCOME MEASURES: Health related quality of life and psychological wellbeing as measured by the women's health questionnaire. Changes in emotional and physical menopausal symptoms as measured by a symptoms questionnaire and depression by the Centre for Epidemiological Studies depression scale (CES-D). Overall health related quality of life and overall quality of life as measured by the European quality of life instrument (EuroQol) and visual analogue scale, respectively. RESULTS: After one year small but significant improvements were observed in three of nine components of the women's health questionnaire for those taking combined HRT compared with those taking placebo: vasomotor symptoms (P<0.001), sexual functioning (P<0.001), and sleep problems (P<0.001). Significantly fewer women in the combined HRT group reported hot flushes (P<0.001), night sweats (P<0.001), aching joints and muscles (P=0.001), insomnia (P<0.001), and vaginal dryness (P<0.001) than in the placebo group, but greater proportions reported breast tenderness (P<0.001) or vaginal discharge (P<0.001). Hot flushes were experienced in the combined HRT and placebo groups by 30% and 29% at trial entry and 9% and 25% at one year, respectively. No significant differences in other menopausal symptoms, depression, or overall quality of life were observed at one year. CONCLUSIONS: Combined HRT started many years after the menopause can improve health related quality of life. TRIAL REGISTRATION: ISRCTN 63718836.

Main morbidities recorded in the women's international study of long duration oestrogen after menopause (WISDOM): a randomised controlled trial of hormone replacement therapy in postmenopausal women.

OBJECTIVE: To assess the long term risks and benefits of hormone replacement therapy (combined hormone therapy versus placebo, and oestrogen alone versus combined hormone therapy). DESIGN: Multicentre, randomised, placebo controlled, double blind trial. SETTING: General practices in UK (384), Australia (91), and New Zealand (24). PARTICIPANTS: Postmenopausal women aged 50-69 years at randomisation. At early closure of the trial, 56,583 had been screened, 8980 entered run-in, and 5692 (26% of target of 22,300) started treatment. INTERVENTIONS: Oestrogen only therapy (conjugated equine oestrogens 0.625 mg orally daily) or combined hormone therapy (conjugated equine oestrogens plus medroxyprogesterone acetate 2.5/5.0 mg orally daily). Ten years of treatment planned. PRIMARY OUTCOMES: major cardiovascular disease, osteoporotic fractures, and breast cancer. SECONDARY OUTCOMES: other cancers, death from all causes, venous thromboembolism, cerebrovascular disease, dementia, and quality of life. RESULTS: The trial was prematurely closed during recruitment, after a median follow-up of 11.9 months (interquartile range 7.1-19.6, total 6498 women years) in those enrolled, after the publication of early results from the women's health initiative study. The mean age of randomised women was 62.8 (SD 4.8) years. When combined hormone therapy (n=2196) was compared with placebo (n=2189), there was a significant increase in the number of major cardiovascular events (7 v 0, P=0.016) and venous thromboembolisms (22 v 3, hazard ratio 7.36 (95% CI 2.20 to 24.60)). There were no statistically significant differences in numbers of breast or other cancers (22 v 25, hazard ratio 0.88 (0.49 to 1.56)), cerebrovascular events (14 v 19, 0.73 (0.37 to 1.46)), fractures (40 v 58, 0.69 (0.46 to 1.03)), and overall deaths (8 v 5, 1.60 (0.52 to 4.89)). Comparison of combined hormone therapy (n=815) versus oestrogen therapy (n=826) outcomes revealed no significant differences. CONCLUSIONS: Hormone replacement therapy increases cardiovascular and thromboembolic risk when started many years after the menopause. The results are consistent with the findings of the women's health initiative study and secondary prevention studies. Research is needed to assess the long term risks and benefits of starting hormone replacement therapy near the menopause, when the effect may be different. TRIAL REGISTRATION: Current Controlled Trials ISRCTN 63718836.