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A J Crockett

Publications and source records attributed to A J Crockett.

At least 19 recordsLinked to original sources
PubMed2001

Domiciliary oxygen for interstitial lung disease.

BACKGROUND: Retrospective survival data have suggested poor effectiveness of oxygen therapy in patients with interstitial lung disease (ILD). OBJECTIVES: To determine the effect of domiciliary oxygen therapy on survival and quality of life in patients with a diagnosis of ILD and hypoxaemia. SEARCH STRATEGY: Randomized Controlled Trials (RCTs) were identified using the Cochrane Airways Group register and the search terms: (home OR domiciliary AND oxygen AND (Interstitial lung disease OR ILD OR pulmonary fibrosis OR IPF)). SELECTION CRITERIA: Any randomized controlled trial (RCT) in adult patients with hypoxaemia and ILD that compared long term domiciliary or home oxygen therapy with a control group. DATA COLLECTION AND ANALYSIS: Only one unpublished RCT was identified. MAIN RESULTS: Only one trial was identified. Mortality for both the oxygen treated and control groups was approximately 91% after 3 years (Peto odds ratio 0.99, 95% confidence intervals 0.16,6.26). The effect of oxygen therapy on quality of life and physiological parameters was not reported. REVIEWER'S CONCLUSIONS: The assumption that home oxygen therapy has a beneficial survival effect in patients with ILD has not been demonstrated in the single RCT identified.

Confidence Intervals↗
PubMed2001

Survival on long-term oxygen therapy in chronic airflow limitation: from evidence to outcomes in the routine clinical setting.

BACKGROUND: Two previous randomized controlled trials (RCT) demonstrated that the administration of long-term oxygen therapy (LTOT) improved survival in selected patients with hypoxic chronic obstructive pulmonary disease (COPD) or chronic airflow limitation (CAL). AIMS: The aim of the present study was to investigate whether the survival of CAL patients prescribed LTOT at Flinders Medical Centre (FMC) was gender and age related, and equivalent to that of the previous RCT. METHODS: A list of patients prescribed domiciliary oxygen therapy for CAL at FMC was generated from Respiratory Unit records and hospital financial records for the supply of this therapy. Survival was compared with that reported for the original RCT, and for Swedish and Belgian COPD patients. Factors influencing survival were studied. RESULTS: Five hundred and five (249 males, 256 females) patients were prescribed LTOT for CAL at FMC during the study period and included in the survival analysis. The patients were elderly with multiple comorbidities. Survival was less than for the control arms of the previous RCT (apart from the Medical Research Council Working Party (MRC) female group) but comparable with recent overseas data. Overall crude survival was 75.1%, 51.3%, 18.9% and 1.1% at 1, 2, 5 and 10 years respectively. Females experienced longer survival than males. Multivariate analysis indicated that age, forced expiratory volume in 1 s, body mass index (BMI) and the number of comorbidities were prognostic indicators for females; BMI was a prognostic indicator for males. A survival advantage existed for females using at least 19 h concentrator oxygen per day. CONCLUSIONS: In routine practice, survival of unselected CAL patients with multiple comorbidities is less than that reported in the original RCT.

Age Factors↗
PubMed2001

A review of long-term oxygen therapy for chronic obstructive pulmonary disease.

This study aimed to review the evidence for the use of long-term oxygen therapy for patients with chronic obstructive pulmonary disease (COPD). The design was a systematic Cochrane review of randomized controlled trials (RCTs) of long-term oxygen therapy for COPD and main outcome measure was survival on home oxygen therapy. Five RCTs were identified. Data from two trials of nocturnal oxygen therapy in mild to moderate hypoxaemia were aggregated. Data from the other three trials could not be aggregated because of differences in trial design and patient selection. Treatment with continuous versus nocturnal oxygen therapy produced a significant improvement in mortality after 24 months [Peto odds ratio 0.45, 95% confidence interval (95% CI) 0.25-0.81] for the continuous therapy group. Treatment with oxygen therapy versus no oxygen therapy showed a significant improvement in mortality after five years in the group receiving oxygen therapy (Peto odds ratio 0.42, 95% CI 0.18-0.98). There was no difference in mortality for patients with COPD and mild to moderate daytime hypoxaemia and nocturnal desaturation receiving nocturnal oxygen therapy versus no oxygen therapy or sham treatment. Long-term oxygen therapy versus no oxygen therapy in patients with COPD and moderate hypoxaemia had no effect on survival. In conclusion, long-term oxygen therapy improved survival in a selected group of COPD patients with severe hypoxaemia but few co-morbidities. Long-term oxygen therapy did not improve survival in patients with moderate hypoxaemia or in those with mild to moderate hypoxaemia and arterial desaturation at night.

Adult↗
PubMed2000

Mucolytics for bronchiectasis.

BACKGROUND: Bronchiectasis is usually characterised by the production of large quantities of sputum that patients frequently have difficulty in expectorating. Mucolytic agents target hyper-secretion or changed physiochemical properties of sputum to make it easier to clear. One drug, recombinant human DNase, breaks down the DNA that is released at the site of infection by neutrophils. OBJECTIVES: The objective of this review was to assess the effects of ingested or inhaled mucolytics in patients with bronchiectasis. SEARCH STRATEGY: We searched the Cochrane Airways Group trials register, reference lists of relevant articles. We also contacted experts in the field and drug companies. SELECTION CRITERIA: Randomised trials of mucolytic treatment in people with bronchiectasis but not cystic fibrosis. DATA COLLECTION AND ANALYSIS: Data extraction was performed independently by two reviewers. Study authors were contacted for confirmation. MAIN RESULTS: Two trials were included. In one study, compared to placebo, high doses of bromhexine combined with antibiotics eased difficulty in expectoration (weighted mean difference -0.53, 95% confidence interval -0.81 to -0.25 at 16 days). There was also a reduction in sputum production with bromhexine (weighted mean difference -21.5%, 95% confidence interval -38.9 to -4.1 at day 16). There was no difference in forced expiratory volume. In a second study, compared to placebo, recombinant human DNase showed no difference in forced expiratory volume or forced vital capacity. Adverse effects, including influenza-like symptoms, were more common in the group receiving recombinant human DNase. REVIEWER'S CONCLUSIONS: There is not enough evidence to evaluate the routine use of mucolytics for bronchiectasis. High doses of bromhexine coupled with antibiotics may help with sputum production and clearance.

Anti-Bacterial Agents↗
PubMed2000

Domicilary oxygen for chronic obstructive pulmonary disease.

BACKGROUND: Long-term domiciliary oxygen therapy has become one of the major forms of treatment for hypoxaemic chronic obstructive pulmonary disease (COPD) patients. OBJECTIVES: To determine the effect of domiciliary oxygen therapy on survival and quality of life in patients with COPD. SEARCH STRATEGY: Randomised controlled trials (RCTs) were identified using the Cochrane Airways Group COPD register using the search terms: (home OR domiciliary) AND oxygen. SELECTION CRITERIA: Any RCT in patients with hypoxaemia and COPD that compared long term domiciliary or home oxygen therapy with a control treatment. DATA COLLECTION AND ANALYSIS: Data extraction was performed independently by two reviewers. MAIN RESULTS: Four randomised controlled trials were identified. Data from none of these trials could be aggregated because of differences in trial design and patient selection. NOTT 1980, continuous oxygen therapy versus nocturnal oxygen therapy: there was a significant improvement in mortality after 24 months (Peto odds ratio 0.45, 95% confidence interval 0.25 to 0.81). MRC 1981, domiciliary oxygen therapy versus no oxygen therapy: there was a significant improvement over five years in mortality in the group receiving oxygen therapy (Peto odds ratio 0.42, 95% confidence interval 0.18 to 0.98). Fletcher 1992, nocturnal oxygen versus no oxygen in patients with COPD and arterial desaturation at night: there was no difference in mortality at 36 months. Gorecka 1997, long term oxygen versus no oxygen in moderate hypoxaemia: there was no effect on survival for up to three years of follow up. REVIEWER'S CONCLUSIONS: Long term oxygen therapy improved survival in a selected group of COPD patients with severe hypoxaemia (arterial PO2 less than 8.0 kPa). Long term oxygen did not appear to improve survival in patients with moderate hypoxaemia or in those with only arterial desaturation at night.

Home Care Services↗
PubMed2000

Composition of alveolar surfactant changes with training in humans.

OBJECTIVE: We test the hypothesis that the changes we observed previously in the relative amounts of disaturated phospholipids (DSP), cholesterol (CHOL), and surfactant protein-A (SP-A) in human alveolar surfactant in response to acute exercise, and which were related to fitness, can be induced by training. METHODOLOGY: We examine the effect of 7 weeks' training on these major surfactant components, together with surfactant protein-B (SP-B), in bronchoalveolar lavage fluid harvested from 17 males, both at rest and after acute exercise. Fitness was assessed as workload/heart rate achieved during cycling for 30 min at 90% of theoretical maximal heart rate, and was increased in all subjects following training (mean increase 22.2+/-3.91%; P = 0.001). RESULTS: Training significantly increased the SP-A/DSP, SP-B/DSP, SP-A/CHOL and SP-A/SP-B ratios in whole surfactant harvested from subjects both at rest and immediately following exercise. Training also increased the SP-B/CHOL ratio at rest. Changes were particularly marked at rest in the SP-A/DSP, SP-A/CHOL, and SP-B/CHOL ratios in the tubular myelin-rich fraction, and after exercise in the SP-A/DSP, SP-A/CHOL, and SP-A/SP-B ratios in the tubular myelin-poor fraction. CONCLUSION: We conclude that training markedly alters the composition of alveolar surfactant both at rest and with exercise; the physiological significance of these changes remains to be determined.

Adolescent↗
PubMed2000

An association between length of stay and co-morbidity in chronic airflow limitation.

OBJECTIVE: To examine factors which impact on the length of stay and readmission for patients with chronic airflow limitation at a South Australian hospital from December 1996 until March 1998. DESIGN: Discharges from Flinders Medical Centre for patients aged > or = 18 years, where chronic airflow limitation was an active problem, and including a subset with a primary diagnosis of chronic airflow limitation, were identified, retrospectively, by the center's Clinical Coding Service from the hospital's in-patient separation database. SETTING: Flinders Medical Centre, Adelaide, South Australia. OUTCOME MEASURES: Length of stay; number of co-morbidities; readmission within 28 days. RESULTS: Five-hundred and twenty discharges (male:female, 258:262) with a primary diagnosis of chronic airflow limitation (ANDRG-3 177, chronic obstructive airways disease) were identified. Readmission within 28 days was related to the number of co-morbidities and to age. A relationship between length of stay and the number of co-morbidities was identified. A mean length of stay of 6.39 days was found for patients with less than five co-morbidities, 5.36 at their first admission to Flinders Medical Centre and 3.25 at their first admission to Flinders Medical Centre with no co-morbidities. These mean lengths of stay fall below overseas data previously published and are consistent with Kong's estimate of an ideal mean length of stay of 3.2 days when a clinical management guideline is used in low-risk chronic airflow limitation patients. CONCLUSIONS: Length of stay and readmission to hospital within 28 days of patients with a primary diagnosis of chronic airflow limitation is at least partly related to the number of co-morbidities and to age. The study has highlighted the difficulty of relying on changes to aggregate data as outcome measures for these patients.

Adult↗
PubMed2000

Comparison of two hydrodensitometric methods for estimating percent body fat.

This study compared the two following hydrodensitometric methods for estimating percent body fat (%BF): 1) estimation of residual volume (RV) by helium dilution before and after measurement of immersed mass at RV, and 2) determination of immersed mass at a comfortable level of expiration (approximately functional residual capacity) with measurement of the associated gas volume by oxygen dilution. Twelve men [27.9 +/- 7.5 (SD) yr; 79.32 +/- 12.79 kg; 180.5 +/- 9.9 cm] were tested for %BF via both methods on each of two separate visits within 3 days by using a counterbalanced design. The two helium dilution measurements yielded a technical error of measurement of 0.2% BF and an intraclass correlation coefficient of 0.999. Corresponding values for the oxygen dilution method were 0.4% BF and 0.999, respectively. There was no difference (P = 0.80) between the helium dilution (16.9 +/- 9.3% BF) and oxygen dilution (16.9 +/- 9.4% BF) methods, and the individual differences ranged from -0.7 to 0.6% BF. The interclass correlation coefficient between the two methods was 0.999 with a SE of estimate of 0.4% BF. Whereas both methods were precise and reliable and yielded similar results, the oxygen dilution technique was more expedient and was preferred by the subjects because they were not required to exhale to RV.

Adipose Tissue↗
PubMed1999

Adult domiciliary oxygen therapy: position statement of the Thoracic Society of Australia and New Zealand.

Evidence shows that patients with chronic obstructive pulmonary disease and a stable daytime PaO2 of 55 mm Hg or less will have longer life expectancy if given supplemental oxygen to keep the PaO2 above 60 mm Hg, preferably for longer than 15 hours a day, including sleep. There is some evidence for improved quality of life. It is reasonable to offer this therapy for other lung diseases which cause chronic hypoxaemia, and there are also less well defined indications for supplemental oxygen during exercise, sleep and air travel.

Adult↗
PubMed1999

Effects of long-term oxygen therapy on quality of life and survival in chronic airflow limitation.

Chronic airflow limitation (CAL) is a major contributor to the burden of ill-health in Australia and, where hypoxia is present, can be treated with home oxygen therapy (HOT). At Flinders Medical Centre, a prospective longitudinal study was undertaken to examine the impact of HOT on the health-related quality of life (HRQoL) of subjects with CAL. All eligible adult patients, aged < 80 yrs, with a primary diagnosis of CAL who met the prescription guidelines of the Thoracic Society of Australia and New Zealand were offered HOT and invited to participate. After baseline assessment, subjects were followed-up 3, 6 and 12 months after commencement of HOT. Physiological assessment and three validated HRQoL measures were applied, the Nottingham Health Profile (NHP), the Chronic Respiratory Questionnaire (CRQ) and, for a subset of the patients, the Medical Outcomes Study short-form 36-item questionnaire (SF-36). This study reports the results from January 1, 1991 to July 31, 1997. One hundred and fourteen CAL patients were included in the study. Female subjects experienced significant improvements from baseline in the energy, emotional reactions, sleep and physical mobility areas of the NHP, in the fatigue, emotional function and mastery dimensions of the CRQ and in the role-physical, vitality, role-emotional, and mental health dimensions of the SF-36. Males experienced significant improvements in the emotional reactions, sleep and social isolation areas of the NHP, in the fatigue dimension of the CRQ and in the vitality dimension of the SF-36. Some of the improvements in the various domains persisted for > 6 months. Female patients prescribed home oxygen therapy appear to have a greater overall improvement in health-related quality of life and survival than males. Follow-up is continuing.

Adult↗
PubMed1998

Adult domiciliary oxygen therapy. Position statement of the Thoracic Society of Australia and New Zealand.

Evidence shows that patients with chronic obstructive pulmonary disease and a stable daytime PaO2 of 55 mm Hg or less will have longer life expectancy if given supplemental oxygen to keep the PaO2 above 60 mm Hg, preferably for longer than 15 hours a day, including sleep. There is some evidence for improved quality of life. It is reasonable to offer this therapy for other lung diseases which cause chronic hypoxaemia, and there are also less well defined indications for supplemental oxygen during exercise, sleep and air travel.

Adult↗
PubMed1996

The MOS SF-36 health survey questionnaire in severe chronic airflow limitation: comparison with the Nottingham Health Profile.

This study documents the cross-sectional, health-related quality of life (HRQOL) measures obtained at baseline for patients with severe chronic airways limitation (CAL) being assessed for home oxygen therapy (HOT) at the Flinders Medical Centre, Adelaide, South Australia. Two generic quality of life instruments, the Nottingham Health Profile (NHP) and the Medical Outcomes Study (MOS) short form 36-item questionnaire (SF-36), were administered by interview to the same patients to permit comparisons to be made between the two instruments. SF-36 mean scores were also compared with scores obtained in separate studies of a South Australian elderly general population and of groups of Australian subjects with various medical and psychiatric conditions. NHP mean scores were compared with scores from an elderly group of Adelaide residents from a household survey. HRQOL measures were obtained for 60 patients, 32 males and 28 females. At assessment for HOT, patients with severe CAL were experiencing severe impairment in their quality of life in comparison to age-matched South Australian norms, with physical disability the major limitation. There were several significant correlations between the domains of the SF-36 and the NHP which were predominantly gender-specific. Only small decrements in mental health were found with the SF-36 questionnaire. The SF-36 and the NHP appear to provide discrepant information for severely disabled CAL patients for the subjective domains of emotional and mental health.

Adaptation, Psychological↗
PubMed1996

Initial trends in quality of life and survival in CAL patients on domiciliary oxygen therapy.

Domiciliary oxygen therapy has become a major form of treatment for chronic airflow limitation (CAL), and has been demonstrated to increase survival and reduce hospitalization. The impact of long-term domiciliary oxygen therapy on health-related quality of life is less clear. This study was conducted to document prospectively the quality of life and survival of patients with CAL after being prescribed domiciliary oxygen therapy at the Flinders Medical Centre in South Australia. The study sample consisted of 57 adult patients (29 males and 28 females, aged 80 yrs or less) with severe CAL referred to the Respiratory Unit for domiciliary oxygen therapy. Prior to the commencement of oxygen therapy, baseline physiological assessment was performed and the Nottingham Health Profile (NHP), the Chronic Respiratory Disease Questionnaire (CRDQ), a Quality of Life Thermometer (QOLTH) and Life Satisfaction Index (LSI) were used to measure the health-related quality of life (HR-QOL). Follow-ups occurred at 3 and 6 months after the commencement of home oxygen therapy. Quality of life at baseline was not correlated with the physiological parameters of lung function and blood gas analysis. However, considerable correlation was found between two of the quality of life instruments used. The female patients on home oxygen therapy experienced some improvement in several dimensions of quality of life measured by the instruments. The observations were less clearcut for males. By the time the patients' physiological and clinical condition has deteriorated for them to fulfil prescription guidelines for home oxygen therapy, patients with chronic airflow limitation are experiencing a marked reduction in quality of life. However, the strength of the reported findings must be tempered by remaining questions over the validity of the instruments and their responsiveness to change; and by the small number of enrolments so far, and the relatively short period of follow-up.

Aged↗
PubMed1995

The changing prevalence of asthma-like respiratory symptoms in South Australian rural schoolchildren.

OBJECTIVE: To describe the changing prevalence of wheezy breathing and doctor-diagnosed asthma, as obtained by questionnaire data, from the years 1984-92 in a sample of South Australian rural schoolchildren. METHODOLOGY: A cross-sectional study of three populations of schoolchildren from the South Australian rural towns of Burra (mid-north), Gladstone (mid-north) and Kingston (southern, coastal). The cumulative or lifetime prevalences and the 12-month period prevalence (current) of respiratory symptoms were estimated from questionnaire data obtained from parental responses for 1032 schoolchildren aged from 5 to 18 years, and compared with prevalences obtained from a previous study. RESULTS: The overall cumulative prevalence of wheezy breathing in 1992 was 36.2%, an increase from 24.1% in 1984 with a 12-month period prevalence of 25.0%. The 1992 cumulative prevalence of doctor-diagnosed asthma was 23.3%. There was no difference in the prevalence of wheeze between the three rural regions studied. A trend to a higher prevalence of doctor-diagnosed asthma in one of the three regions was thought to be due to medical specialist input. CONCLUSIONS: The cumulative prevalence for wheeze among school-age children in South Australian rural communities has increased in the period 1984-92. There were no regional differences in the cumulative prevalence rates. The results confirm previous studies in Victoria and New South Wales.

Adolescent↗
PubMed1995

Spirometric standards for healthy adult lifetime nonsmokers in Australia.

The aim of this study was to develop suitable spirometric prediction equations for asymptomatic Caucasian adults in the Australian population. These equations were compared with those of previous studies and constants were presented which, when associated with the prediction equations, permitted the calculation of 5% tolerance intervals for lung function. The 1,302 subjects (aged 18-78 yrs) who underwent pneumotachograph spirometry, using techniques recommended by the American Thoracic Society, were a sample from metropolitan Adelaide, South Australia. The variables recorded were sex, age, height, mass, forced expiratory volume in one second (FEV1), forced vital capacity (FVC), peak expiratory flow rate (PEFR), forced mid-expiratory flow (FEF25-75%) and FEV1/FVC ratio. Complete data were obtained for 614 females and 621 males, but the sample was reduced to 249 females and 165 males when only lifetime nonsmokers with no adverse bronchial symptoms were selected. Prediction equations of normal lung function were obtained from the reduced sample by multiple regression, with age, height and functions of both age and height as predictors. The derived equations did not differ significantly from the majority of previously reported equations and were generally superior in their ability to predict the lung function of the asymptomatic ex-smokers who were part of the original sample. Analysis of the sensitivity, specificity and predictive power of 5% tolerance limits for the presence of symptoms revealed the important roles of FEV1, FEV1/FVC and FEF25-75% in diagnostic testing. The present prediction equations are recommended for use on the Australian population and on populations with similar Caucasian characteristics.

Adult↗
PubMed1994

Trends in chronic obstructive pulmonary disease mortality in Australia.

OBJECTIVE: To examine trends in mortality from chronic obstructive pulmonary disease in the Australian population from 1964 to 1990. DESIGN: Review of national data on deaths from chronic obstructive pulmonary disease. We calculated direct annual age-standardised mortality rates for women and men (based on the 1976 age distribution of the Australian population), cumulative mortality rates and future mortality trends. Age-standardised mortality rates based on the world standard population were calculated and compared with mortality rates from lung cancer. RESULTS: Male age-standardised mortality increased 1.6-fold from 1964 to 1970 and subsequently declined. In 1990 the male mortality rate was 5% less than in 1964. Female age-standardised mortality has shown a 2.6-fold increase from 1964 to 1990. CONCLUSIONS: Chronic obstructive pulmonary disease seems likely to be a major health problem in Australia for many years to come. If present trends continue, female mortality from chronic obstructive pulmonary disease may equal male mortality by the middle of the next decade.

Adolescent↗