Recurrences determine the dynamics.

We show that under suitable assumptions, Poincare recurrences of a dynamical system determine its topology in phase space. Therefore, dynamical systems with the same recurrences are dynamically equivalent. This conclusion can be drawn from a theorem proved in this paper which states that the recurrence matrix determines the topology of closed sets. The theorem states that if a set of points M is mapped onto another set N, such that two points in N are closer than some prescribed fixed distance if and only if the corresponding points in M are closer than some, in general different, prescribed fixed distance, then both sets are homeomorphic, i.e., identical up to a continuous change in the coordinate system. The theorem justifies a range of methods in nonlinear dynamics which are based on recurrence properties.

Can beta agonists cause dilated cardiomyopathy?

We report a case of dilated cardiomyopathy that we believe is secondary to excessive use of inhaled beta agonists. Clinicians should be mindful of this possibility when using beta agonists to treat patients with obstructive airways disease; particularly if there is already recognised left ventricular dysfunction.

Cannabis use and cancer of the head and neck: case-control study.

OBJECTIVE: To investigate whether cannabis smoking increases the risk of head and neck cancer. DESIGN: Case-control study. SUBJECTS AND METHODS: Cases of head and neck cancer < or =55 years identified from hospital databases and the Cancer Registry, and controls randomly selected from the electoral roll completed interviewer-administered questionnaires. Logistic regression was used to estimate the relative risk of head and neck cancer. RESULTS: There were 75 cases and 319 controls. An increased risk of cancer was found with increasing tobacco use, alcohol consumption, and decreased income but not increasing cannabis use. The highest tertile of cannabis use (>8.3 joint years) was associated with a nonsignificant increased risk of cancer (relative risk = 1.6, 95% confidence interval, 0.5-5.2) after adjustment for confounding variables. CONCLUSIONS: Cannabis use did not increase the risk of head and neck cancer; however, because of the limited power and duration of use studied, a small or longer-term effect cannot be excluded.

The New Zealand national junior doctors' strike: implications for the provision of acute hospital medical services.

The New Zealand junior doctors' strike provided an opportunity to consider strategies that might be employed to overcome the international shortage of junior doctors. This article reports the experience of the emergency department (ED) and internal medicine (IM) services at Wellington Hospital during the national strike, in which medical services were primarily provided by specialist consultants in addition to, or as part of, their routine work. During the strike, elective admissions and outpatient clinics were mostly cancelled. In the ED, the waiting times and length of stay were markedly reduced. In IM, the proportion of patients admitted to the short stay unit rather than the general medical wards increased. Notwithstanding the different work circumstances, in both services one senior doctor carried the workload of at least two junior doctors. The deployment of additional senior medical staff to acute hospital services could greatly reduce the total number of doctors required. This strategy would have implications in terms of supporting acute medicine specialty initiatives, training, quality of care and funding.

Acceptability of electronic cigarettes as an option to replace tobacco smoking for alcoholics admitted to hospital for detoxification.

AIM: A feasibility/acceptability trial was undertaken at Ward 5, Kenepuru Hospital, Porirua, to ascertain whether electronic cigarettes (e-cigarettes) were a useful option to replace or reduce smoking in the detoxification ward. METHODS: Two groups of patients were studied. Tobacco use and dependency data were collected for each. The first group was surveyed on the usefulness of standard nicotine replacement therapy (NRT). The second group were offered e-cigarettes with the option of standard NRT as well. All were asked to record their use of cigarettes, e-cigarettes and NRT during their stay on the ward, and to comment on their experiences. Outcomes monitored were self-reported use of NRT and of tobacco. Informal impressions of the nursing staff were also collected, where offered. For the e-cigarette group, a blood sample was taken on day 3 or 4 of their stay in hospital for nicotine/cotinine analysis, to confirm nicotine intake status. RESULTS: E-cigarettes were well tolerated as a form of nicotine replacement, eliciting positive comments, though they were not effective for all. The average reduction in median cigarettes per day was very similar between the group given standard NRT and the e-cigarette group, at 80% and 86% respectively. There were no adverse effects reported. CONCLUSION: The study showed that e-cigarettes were an acceptable form of nicotine replacement for these alcohol-dependent patients during their time in the ward. For heavily tobacco-dependent smokers, e-cigarettes may provide a useful aid to patient management within a hospital setting.

Effects of cannabis on pulmonary structure, function and symptoms.

BACKGROUND: Cannabis is the most widely used illegal drug worldwide. Long-term use of cannabis is known to cause chronic bronchitis and airflow obstruction, but the prevalence of macroscopic emphysema, the dose-response relationship and the dose equivalence of cannabis with tobacco has not been determined. METHODS: A convenience sample of adults from the Greater Wellington region was recruited into four smoking groups: cannabis only, tobacco only, combined cannabis and tobacco and non-smokers of either substance. Their respiratory status was assessed using high-resolution CT (HRCT) scanning, pulmonary function tests and a respiratory and smoking questionnaire. Associations between respiratory status and cannabis use were examined by analysis of covariance and logistic regression. RESULTS: 339 subjects were recruited into the four groups. A dose-response relationship was found between cannabis smoking and reduced forced expiratory volume in 1 s to forced vital capacity ratio and specific airways conductance, and increased total lung capacity. For measures of airflow obstruction, one cannabis joint had a similar effect to 2.5-5 tobacco cigarettes. Cannabis smoking was associated with decreased lung density on HRCT scans. Macroscopic emphysema was detected in 1/75 (1.3%), 15/92 (16.3%), 17/91 (18.9%) and 0/81 subjects in the cannabis only, combined cannabis and tobacco, tobacco alone and non-smoking groups, respectively. CONCLUSIONS: Smoking cannabis was associated with a dose-related impairment of large airways function resulting in airflow obstruction and hyperinflation. In contrast, cannabis smoking was seldom associated with macroscopic emphysema. The 1:2.5-5 dose equivalence between cannabis joints and tobacco cigarettes for adverse effects on lung function is of major public health significance.

Poppy seed tea and opiate abuse in New Zealand.

The opium poppy Papaver somniferum contains an array of opiates. There is a variety of methods of preparation that can be used by people with opiate dependence, with patterns of use determined by numerous factors including cost, safety, potency and legal status. The objective of this study was to determine the frequency and nature of poppy seed tea (PST) use by opiate-dependent patients in the form of a written questionnaire. The study took place at the Community Alcohol and Drug Clinic, Wellington, New Zealand, and comprised 24 opiate-dependent patients attending the clinic. A total of 11 of 24 (46%) patients reported having used PST. In five patients currently using PST it represented the major source of opiates, and two had managed to withdraw from use of other opiates with regular PST use. Patients reported a median onset of action of 15 minutes and an effect lasting a median of 24 hours. The major limitation of PST use was the foul taste. PST is used commonly by opiate-dependent patients attending an alcohol and drug clinic in New Zealand. The use of PST as the major source of opiates could be considered favourably within 'harm reduction' philosophies, because of its low cost, legal availability and oral route of administration. Conversely, there is the potential for PST to act as a 'gateway drug' by inducing opioid dependence and introducing people to the culture of drug abuse.

Streptococcus gallinaceus bacteraemia in an abattoir worker presenting with a febrile illness.

Streptococcus gallinaceus is a newly described species of viridans streptococci, previously only identified as causing disease in broiler chickens. This organism was recovered in pure culture from blood taken from a New Zealand abattoir worker presenting with a febrile illness. This first report of bacteraemia caused by S. gallinaceus in a human may help the understanding of the ecology of this recently described organism.

Thiamin concentration in geriatric hospitalized patients using frusemide.

AIM: To assess the association between thiamin concentration, frusemide use, and renal function in older adults. METHOD: Thiamin concentration was measured in 73 consecutive admissions of patients aged over 65 years in a secondary care hospital. The patients were assigned to the study or control group based on frusemide use. A two-sample t test estimated the association between frusemide use and thiamin concentration and regression between thiamin concentration and EGFR. RESULTS: The mean (SD) thiamin concentration was 181.7 (64.6) nmol/L in those using frusemide and 169.3 (46.8) in non-users, P =0.35. There was a weak linear relationship between thiamin concentration and EGFR, with thiamin concentration being 17.0 nmol/L lower per 30 ml/min greater EGFR, P=0.076. Thiamin concentration was below the reference range in 20/73 (27.4%) of the participants. CONCLUSION: We found no association between frusemide use and thiamin concentration, but showed a significant prevalence of lower thiamin concentration in the study population of older adults.

Beware of paracetamol use in alcohol abusers: a potential cause of acute liver injury.

There may be under-recognition of acute liver injury following reported therapeutic use of paracetamol in alcoholics. We present the case of an alcoholic patient who developed acute liver injury suspicious for chronic paracetamol toxicity on two occasions. The likely contribution of chronic paracetamol was not recognised at her second presentation, reflecting a need for increased awareness of this potential cause of acute liver injury. The biochemical hallmark of the syndrome is the 'towering' aspartate-aminotransferase (AST), often in the thousands; transaminases above 500 U/L should never be dismissed as secondary to alcoholic liver disease alone. Whether alcoholics are at increased risk of toxicity from therapeutic doses of paracetamol remains controversial, although many cases have been described for over 30 years. Randomised controlled trials to date have failed to show significant hepatic derangement in newly abstinent alcoholics exposed to short courses of paracetamol. We argue that these studies do not reflect the realities of paracetamol use in this population. In addition, alcoholics are at risk of accidental 'staggered overdoses', or repeated supra-therapeutic ingestions. In cases of suspected paracetamol toxicity, administration of the antidote n-acetyl cysteine (NAC) should be considered, even when the patient's serum paracetamol level is normal.

Patterns of prescription drug misuse presenting to provincial drug clinics.

AIM: To survey new patients, presenting to three drug clinics, on the patterns, usage and costs of prescription pharmaceuticals. METHOD: Consecutive patients seen by the medical staff for assessment had a 7-day history recorded for prescription drug (PD) usage, and the associated costs of these from street sources. RESULTS: There were 37 patients (26 males) with a mean age of 34 years (21-51). Ten reported using only intravenous (IV) morphine, at a median dose of 105 mg/day (40-600), at a mean cost of 56 cents/mg. Another 12 reported methadone as their sole opioid at a median dose of 50 mg/day (27-70), at a mean cost of 81 cents/mg. A further 11 used a mixture of opioids, predominantly morphine and methadone but also dihydrocodeine (3), oxycodone (1), tramadol (1) and codeine (2). Seventeen reported also using hypnosedatives, but did not report high doses of these. The overall weekly expenditure on PDs was $367/week (0-2100). CONCLUSIONS: Morphine and methadone remain the predominant street opioid PDs in this region. Street prices have reduced, perhaps reflecting greater drug availability in accordance with increased national prescribing of opioids. There is continuing diversion of PDs to the street which is an ongoing Public Health issue requiring coordinated responses, including improved prescribing training, pain guidelines, drug clinic policy and actions by Medsafe, Police and regulatory bodies to contain this problem.

Misuse of over-the-counter codeine-containing analgesics: dependence and other adverse effects.

AIM: To review cases of codeine dependency from over-the-counter (OTC) combination analgesics admitted to a hospital detoxification unit. METHOD: Case records of all admissions following an index case were reviewed over a 2-year period. RESULTS: There were 7 cases reporting chronic excess of Nurofen Plus, of which 6 had prior or current histories of alcohol dependency. Complications which were likely contributed by excessive ibuprofen consumption included: gastric ulcer (4 patients), gastrointestinal bleeding (3), hepatotoxicity (1), and inflammatory bowel conditions (2). CONCLUSIONS: This pattern of admissions is new to the detoxification unit, and may relate to higher codeine content in the combination product, and marketing strategies. These cases likely represent the severer end of the spectrum of codeine dependency acquired from OTC pharmacy sources. The paucity of evidence to support additional benefit from the inclusion of codeine in analgesic combination products is concerning. There is a need for increased pharmacovigilance around these and other OTC medications.

Alcohol cardio-protection has been talked up.

Doctors have been promoting alcohol as a health tonic for a very long time. The last 30 years has seen the accumulation of a considerable medical literature investigating the potential role of alcohol use as a protection against coronary heart disease. When viewed through the lens of two major early reviews in the mid-1980s, Sir Richard Doll's contributions of the mid-1990s, two large meta-analyses of 10 years ago and two most recent overviews, the health-giving properties of alcohol use become increasingly debatable. The influence of the alcohol industry is raised as a factor in the exaggeration of alcohol use as a health intervention, in similar fashion to activities of pharmaceutical companies. The status of alcohol as a potentially dangerous recreational drug is emphasised as a warning against talking up alcohol as a cardio-protection manoeuvre by anyone.

Hemochromatosis gene mutations, liver function tests and iron status in alcohol-dependent patients admitted for detoxification.

BACKGROUND: Screening of target populations for hemochromatosis (HFE) gene allele status has been recommended. Alcoholic liver disease may be associated with iron overload and there is evidence of excessive alcohol consumption among patients with hereditary hemochromatosis. This study determined the HFE gene allele status in alcohol-dependent patients and explored the associations between iron status, liver enzymes, and HFE status. METHODS: A total of 151 consecutive patients admitted for alcohol detoxification were tested for HFE mutations, iron status, and liver function tests. The prevalence data were compared with those from a New Zealand population. manova was used to compare liver function tests and iron status for subjects with different HFE mutations. RESULTS: Three compound heterozygotes, one homozygote for C282Y, and one homozygote for H63D were found among the 151 patients. For the remaining 146 patients, there was no difference in the distribution of heterozygote status by allele, compared to the general New Zealand population. No HFE mutation: general population 64.4%, alcohol-dependent patients 64.4%; H63D: general population 23.6%, alcohol-dependent patients 28.1%; C282Y: general population 11.9%, alcohol-dependent patients 7.5% (P = 0.20). There was no relationship between liver function tests or iron status and HFE mutation status among the study group. CONCLUSIONS: No evidence has been found in the present that HFE allele status prevalence is different from the general population or associated with different liver function or iron status among alcohol-dependent patients. The cause of altered iron status among alcohol-dependent patients does not appear to be related to HFE status.

New hospital consultant: surviving a difficult period.

The first years of consultant practice are amongst the most stressful in a medical specialist's career. Recognising the likely difficulties is essential if measures are to be put in place to lessen their impact. In this article, recommendations are made on how to balance clinical and non-clinical duties and to obtain the support required for professional development. Self-care of mental and physical health is vital and planning is necessary to ensure that both personal health and a work/life balance are maintained.

Raised plasma homocysteine levels in alcoholism: increasing the risk of heart disease and dementia?

BACKGROUND: Raised plasma homocysteine levels, which may contribute to the increased risk of cardiovascular disease and dementia associated with alcoholism, have been observed in alcohol-dependent male subjects. METHODS: In this study, we measured plasma homocysteine levels in 20 female and 31 male alcoholic subjects admitted to hospital for detoxification. Nutritional status and clinical factors that might predict plasma homocysteine levels were assessed by measurement of red cell folate, vitamin B12, blood alcohol, and liver function tests. RESULTS: The median (interquartile range) plasma homocysteine level on admission was 15.4 micromol/L (11.1 to 19.7), with 27 (53%) subjects having a raised homocysteine level, greater than 15 micromol/L. There was no difference in admission plasma homocysteine levels between the male and female subjects (difference, male versus female 1.9 micromol/L, 95% CI=2.4 to 6.0, p=0.4). Red cell folate, vitamin B12 levels, and blood alcohol level on admission were not significant predictors of admission homocysteine level. CONCLUSION: Severe alcohol dependence is associated with markedly raised plasma homocysteine levels in both females and males. The common condition of alcohol dependence may be an under-recognised risk factor contributing to raised plasma homocysteine levels and the associated risk of vascular and intellectual impairment.