Atopic dermatitis: pathomechanisms and lessons learned from novel systemic therapeutic options

Atopic dermatitis (AD) is a chronic, heterogenous, inflammatory skin disorder associated with a high skin-related health burden, typically starting in childhood and often persisting into adulthood. AD is characterized by a wide range of clinical phenotypes, reflecting multiple underlying pathophysiological mechanisms and interactions between genetics, immune system dysregulation, and environmental factors. In this review, we describe the diverse cellular and molecular mechanisms involved in AD, including the critical role of T cell-driven inflammation, primarily via T helper (Th) 2- and Th17-derived cytokines, many of which are mediated by the Janus kinase (JAK) signaling pathway. These local inflammatory processes interact with sensory neuronal pathways, contributing to the clinical manifestations of AD, including itch, pain, and sleep disturbance. The recent elucidation of the molecular pathways involved in AD has allowed treatment strategies to evolve from broad-acting systemic immunosuppressive therapies to more targeted agents, including JAK inhibitors and cytokine-specific biologic agents. Evidence from the clinical development of these targeted therapies has reinforced and expanded our understanding of the pathophysiological mechanisms underlying AD and holds promise for individualized treatment strategies tailored to specific AD subtypes.

Depression: a psychiatric nursing theory of connectivity

This paper presents a theory of connectivity, which was formulated from the findings of a Classical Grounded Theory study that was designed to capture a sample of people's perceptions of living with depression or caring for individuals with depression. Data were collected from: (1) a focus group consisting of people with depression (n = 7), of which five were patients in the community and two were nurses; (2) one-to-one interviews with patients in the community (n = 5) and nurses (n = 5), three of whom had experienced depression from both sides of the caring process; and (3) two 'happy accident' focus groups (n = 25; n = 18) comprising of healthcare workers with a shared understanding of depression. Purposeful sampling was used initially. Thereafter, in keeping with one of the key tenets of grounded theory, theoretical sampling was used until theoretical saturation occurred. Data were analysed using the constant comparative approach together with the NVivo qualitative analysis software package. The core category that emerged was 'connectivity' relating to the connections and disconnections, which people make in their lives. Six key categories emerged all of which were integrated with the core category. Hence, connectivity provided a significant platform for understanding and responding to the life experience of depression. They were: (1) life encounters on the journey to naming; (2) depression: What's in a name? The silent thief; (3) tentative steps to health care; (4) connective encounters and challenges; (5) connecting with self; and (6) self-connection maintenance. Subsequently, a theory, 'Depression: a psychiatric nursing theory of connectivity', surfaced from the overall findings. We argue that this theory of connectivity provides a framework that people working in the field of holistic treatment and care could use to better understand and respond to the life experience of people living with depression.

Seaweed attachment to bedrock: biophysical evidence for a new geophycology paradigm

Seaweeds are amongst the most obvious and ecologically important components of rocky shore communities worldwide but until now little has been known about the processes involved in their attachment. This multidisciplinary study investigated for the first time the interactions between marine macroalgal holdfasts and their underlying substrata, requiring the development of specialized sample preparation techniques to maintain the structural integrity of the holdfast-bedrock interface. Transmitted plane polarized light microscopy, scanning electron microscopy with energy dispersive spectroscopy and structured light illumination microscopy were used in the examination of the interface between Ascophyllum nodosum (Fucales, Heterokontophyta) and crustose red algae Lithothamnion sp. (Corallinales, Rhodophyta) on granite and limestone substrates. The new evidence presented here represents a paradigm shift in the way we view seaweed attachment because results show that the holdfasts exploit the physical characteristics of the rock-forming minerals in order to penetrate the bedrock and thus facilitate the attachment process. Mineral cleavage planes together with intercrystalline and intracrystalline boundaries and fractures provide penetration pathways for the holdfast tissue. This process causes disaggregation of rock-forming minerals to depths <10 mm and therefore assists in the bioerosion of coastal bedrock. It is concluded that seaweeds are able to cause weathering of natural rock and the term 'geophycology' is introduced to describe seaweed-bedrock interactions, including seaweed-induced weathering.

Early life experiences and their impact on our understanding of depression

This paper presents part of a larger Grounded Theory study, which was designed to capture a sample of people's perceptions of living with or, caring for, individuals with depression. Data were collected from a focus group consisting of people with depression (n = 7). In-depth one-to-one interviews were undertaken with eight further respondents (n = 8). Purposeful sampling was used initially. Thereafter, in keeping with one of the key tenets of grounded theory, theoretical sampling was used. The emergent concepts were pursued until saturation occurred. The constant comparative approach was used to analyse the data together with the NVivo qualitative analysis software package. This paper focuses on the respondents' perceptions of the pre-diagnosis, depression encounter. The key category that emerged was 'the pre-diagnosis phase of depression and the now experience'. Five key themes surfaced within this category: (1) negative impact significant life events; (2) self-blame; (3) personal characteristics; (4) pre-diagnosis, depression unknowingness; and (5) pre-help seeking. The findings suggest that those in the field of human services need to better understand the lived experience of people with depression, in order to provide holistic treatment and care.

Naming of depression: nursing, social and personal descriptors

This paper explores descriptors of depression and begins by exploring nursing descriptors including the nature of assessment and nursing diagnosis and progresses to underpin these major processes by considering social descriptors such as cultural and spiritual constructs. The role and influence of stigma is discussed and an examination of gender influences and experiences is undertaken. The paper concludes by examining personal descriptors in the literature. The overall aim of the paper is (1) to add to nursing knowledge by depicting the grounded realities of the experience of depression and (2) stimulate discussion on the need to provide holistic care pathways that are responsive to the uniqueness of this lived experience and finally to (3) encourage further research on key psycho-social factors associated with depression and the concurring advancement of nursing care. This paper has been completed in the context of an ongoing study into the grounded experience of 'Depression' and the development of a psychiatric nursing theory of connectivity.

Immune responses to AAV in a phase I study for Canavan disease

BACKGROUND

Canavan disease is a rare leukodystrophy with no current treatment. rAAV-ASPA has been developed for gene delivery to the central nervous system (CNS) for Canavan disease. This study represents the first use of a viral vector in an attempt to ameliorate a neurodegenerative disorder.

METHODS

Subjects received intracranial infusions via six cranial burr holes. Adeno-associated virus, serotype 2 (AAV2), mediated intraparenchymal delivery of the human aspartoacylase cDNA at a maximum dose of 1 x 10(12) vector genomes per subject. The immune response and safety profiles were monitored in the follow-up of ten subjects.

RESULTS

Following rAAV2 administration, we found no evidence of AAV2 neutralizing antibody titers in serum for the majority of subjects tested (7/10). In a subset (3/10) of subjects, low to moderately high levels of AAV2 neutralizing antibody with respect to baseline were detected. In all subjects, there were minimal systemic signs of inflammation or immune stimulation. In subjects with catheter access to the brain lateral ventricle, cerebrospinal fluid was examined and there was a complete absence of neutralizing antibody titers with no overt signs of brain inflammation.

CONCLUSIONS

rAAV2 vector administration to the human CNS appears well tolerated. The low levels of immune response to AAV2 detected in 3/10 subjects in this study suggest at this dose and with intraparenchymal administration this approach is relatively safe. Long-term monitoring of subjects and expansion to phase II/III will be necessary in order to make definitive statements on safety and efficacy.

New standardised texts for assessing reading performance in four European languages

AIMS

To develop standardised texts for assessing reading speed during repeated measurements and across languages for normal subjects and low vision patients.

METHODS

10 texts were designed by linguistic experts in English, Finnish, French, and German. The texts were at the level of a sixth grade reading material (reading ages 10-12 years) and were matched for length (830 (plus or minus 2) characters) and syntactic complexity, according to the syntactic prediction locality theory of Gibson. 100 normally sighted native speaking volunteers aged 18-35 years (25 per language) read each text aloud in randomised order. The newly designed text battery was then applied to test the reading performance of 100 normally sighted native speaking volunteers aged 60-85 years (25 per language).

RESULTS

Reading speed was not significantly different with at least seven texts in all four languages. The maximum reading speed difference between texts, in the same language was 6.8% (Finnish). Average reading speeds (SD) in characters per minute are, for the young observer group: English 1234 (147), Finnish 1263 (142), French 1214 (152), German 1126 (105). The group of older readers showed statistically significant lower average reading speeds: English 951 (97), Finnish 1014 (179), French 1131 (160), German 934 (117).

CONCLUSION

The authors have developed a set of standardised, homogeneous, and comparable texts in four European languages (English, Finnish, French, German). These texts will be a valuable tool for measuring reading speed in international studies in the field of reading and low vision research.

Are there potential problems with generic substitution of antiepileptic drugs?

In response to increasing cost pressures, healthcare systems are encouraging the use of generic medicines. This review explores potential problems with generic substitution of antiepileptic drugs (AEDs). A broad search strategy identified approximately 70 relevant articles. Potential problems with generic substitution included: The limited evidence (mainly case reports with some pharmacokinetic studies) appears to support these concerns for older AEDs. As a result, restrictions on use of specific generic AEDs are in place in some countries and recommended by some lay epilepsy organisations. As more AEDs lose patent protection, it is important to examine the question of whether generic substitution may pose problems for patients with epilepsy, and whether there should be safeguards to ensure that both physician and patient are informed when generic substitution occurs.

Characterization of crude oils using fluorescence lifetime data

The average fluorescence lifetimes of nine North Sea crude oils with API gravities of between 20 and 51 were measured using a modular, filter based, instrument developed in-house. Two pulsed light emitting diode (LED) excitation sources (460 and 510 nm) were used to excite fluorescence, the lifetime of which was measured at a range of emission wavelengths. Fluorescence lifetimes were found to vary from 1.8 to 8.2 ns with confidence intervals of +/- 0.11 ns. The average lifetimes at all emission wavelengths were linearly correlated with API gravity and with aromatic concentration with the best results being obtained with the 460 nm excitation source. Predictive models with an accuracy of +/- 7.6 API degrees were generated using partial least-squares methods from average fluorescence lifetimes measured at an emission wavelength of 500 nm using 460 nm excitation. A better correlation was found between the aromatic concentration of the oils and the ratio of the average fluorescence lifetimes at measured at 550 and 650 nm using 460 nm excitation. This led to a quantitative model with an accuracy of +/- 5.4% for aromatic concentration.

Primary malignant neuroepithelial tumors of the kidney: a clinicopathologic analysis of 146 adult and pediatric cases from the National Wilms' Tumor Study Group Pathology Center

Primary malignant neuroepithelial tumors of the kidney (NETKs) comprise a group of primitive, highly malignant neoplasms that histologically and clinically are not well characterized. A large cohort of 146 of these tumors, occurring in adults and children, has been collected at a single depository site, the National Wilms' Tumor Study Group (NWTSG) Pathology Center. The authors undertook a systematic retrospective review of the histologic, ultrastructural, and clinical features of these tumors, based on materials collected by the NWTSG and the consultation files of one of the authors (J.B.B.). Histologic features were generally those of primitive neural tumors with varying amounts of rosettes and neuropil; however, a large proportion of cases displayed unusual features such as spindle cells, ganglion cells, clear cell sarcoma-like foci, rhabdoid cells, epithelioid cells, and organoid foci. CD99 staining had been performed on 69 cases and showed membranous staining in 65. The NETKs were present in patients with a wide age spectrum, ranging from 1 month to 72 years (median, 18 years). EWS/FLI1 fusion analysis using reverse transcriptase-polymerase chain reaction and immunohistochemical stains for cytokeratin, chromogranin, and epithelial membrane antigen were performed successfully on a subset of 45 cases with available paraffin blocks. Only 13 of the 45 were fusion-positive, and there was no correlation between fusion status and histology, presence of rosettes, ultrastructural features, or cytokeratin positivity. CD99-negative cases were usually fusion-negative (six of seven cases), and all three chromogranin-positive cases were fusion-negative. Tumor staging, performed on 72 clearly defined and quantifiable cases by using NWTSG criteria, indicated that these are aggressive tumors, because only six were Stage 1, compared with 16 Stage 2, 31 Stage 3, and 19 Stage 4 lesions. The authors conclude that NETKs are a somewhat diverse group of generally aggressive, high-grade lesions that may present in a wide age range and are difficult to characterize without immunohistochemistry and cytogenetics/molecular biology.

Steady-state clearance rates of warfarin and its enantiomers in therapeutically dosed patients

Previous studies to identify the pharmacokinetics of R- and S-warfarin have not used steady-state area under the curve (AUC) data during therapeutic doses of racemic warfarin. Instead they have used high single doses of either racemic warfarin or a single enantiomer in volunteers or have taken a single blood sample from anticoagulated patients and assumed full compliance and a steady-state status. In this study, a series of steady-state racemic warfarin, R-warfarin, and S-warfarin serum concentrations, during a 24 h dosage interval, was measured in 10 compliant patients (5 females and 5 males) taking racemic warfarin. The anticoagulation status of all 10 patients according to the International Normalised Ratio (INR) was stable. Their mean (SD) age and weight were 67.0 (9.9) yr and 63.9 (15.4) kg. The mean (SD) clearances derived from steady-state AUC values, following therapeutic dosing, for racemic warfarin, R-warfarin, and S-warfarin were 2.40 (0.82), 2.30 (0.65), and 2.80 (1.17) ml/h/kg, respectively. The mean (SD) ratio of S-warfarin clearance was 1.24 (0.40). Comparison of the clearance measured from the AUC, of these patients, to one point determinations assuming steady state for the samples drawn at either 6, 15, or 20 h after dosage (during the dosing interval) showed some statistical differences. Most single point determinations of warfarin clearance assume that a sample of 12 h postdose is equivalent to that of the steady-state concentration, but in this study the steady-state concentration of only 6 patients occurred between 6 and 15 h postdate. This could explain why these studies demonstrate differences in the clearance of R- and S-warfarin compared to the values we have derived from steady-state AUC data using patients with proven compliance and therapeutic doses.

Once a day is best: evidence or assumption? The relationship between compliance and dosage frequency in older people

To rationalise medication in the elderly, physicians often change multiple dose regimens to once daily in the belief that this improves compliance. Effective methods for measuring compliance have only come into use during the last decade. Partly as a result of this, high quality studies comparing once daily with other regimens in the elderly, are lacking. What evidence there is, from investigations which used suboptimum methods and/or mixed (elderly/younger) patient groups, does not justify the widely held view that 'once a day is best', particularly when compared with twice daily regimens.

Prescribing of anti-epileptic drugs in the northern and Yorkshire region: 1992-1995

Epilepsy is a condition for which regular drug treatment is normally prescribed. We have examined the primary care prescribing rates for anti-epileptic drugs (AEDs) in a region of northern England with a population of 6.8 million. Over the 4-year period 1992-1995 the number of AED prescription items issued rose by 15%. A third of this rise is accounted for by increased prescribing of the new anticonvulsants, vigabatrin, lamotrigine and gabapentin, which are primarily indicated for adjunct use. Prescribing of phenytoin and barbiturates fell over the same period, but this reduction was more than compensated for by increased prescribing of carbamazepine and sodium valproate. There were notable differences in both the overall volume and the choice of AEDs used in different health authority areas and these are probably attributable to the influence of the local secondary-care sector on the therapeutic regimens adopted by general practitioners in the area.

Initial evaluation of low-dose phenobarbital as an indicator of compliance with antimalarial drug treatment

Since poor compliance with antimalarial therapy is often suspected but difficult to prove, this study attempted to establish a model for predicting the plasma concentration of phenobarbital (given in low doses in conjunction with the drug) as an indicator of compliance. Phenobarbital was chosen because its value had been demonstrated as a marker of compliance in long-course therapies, any significant departure from steady-state concentrations (achieved with full compliance) indicating one or more missed doses. Therapy for uncomplicated malaria varies from 5 days with artesunate to 7 days with quinine + tetracycline. Volunteers with confirmed falciparum malaria were randomized into 5 groups and given malaria therapy as well as phenobarbital daily for 3-7 days. Plasma samples for determination of phenobarbital concentrations were taken just prior to the daily dose of phenobarbital. Although there was a clear and predictable individual pattern of blood concentrations following each dose of phenobarbital, inter-individual variation in blood levels was significant and reduced their predictive value beyond the second day's dose. The cause of the variations is not clear; it could be attributable to different sources of the drug, previous intake of phenobarbital by the patient, or differences in drug absorption and disposition in malaria patients. Results for the 5-day artesunate regimen suggest that phenobarbital may be useful as a marker of compliance if the patient stops medication after 3 days; clear differences were evident at the end of the course of treatment between plasma phenobarbital concentrations in individuals completing the 5-day course and those who stopped after 3 days. For the quinine-tetracycline regimen, results suggest that it may be possible to discriminate between subjects where there is a 3-day difference in treatment. Phenobarbital is a better discriminant when dosing is every 24 hours as with artesunate, rather than the 8-hourly regimen for quinine-tetracycline. When measuring compliance for malaria treatment, if it is important to know what proportion of patients reach 3, 5 or 7 days of compliance, then phenobarbital might have a role to play in this assessment, but further investigations in more patients would be required. Alternatively, different markers could be used for the doses to be given on these days and, as long as the patient does not mix the doses for the different days, sequential doses and determination of compliance could be based on an "all or none" detection of the marker rather than on drug levels.

[Using Peplau's theory in the nurse-patient relationship]

In caring for a person suffering from depression, Peplau's theory of "Interpersonal Relations" was found to be both effective and representative of what psychiatric nurses do. Peplau's work, initially published in 1952, continues to offer a major contribution to nursing knowledge and deserves the significance ascribed to it in the 1990s. Below, a report on the learning experience for both the patient and the carrier.

The pharmacokinetics of methadone in healthy subjects and opiate users

AIMS

There is some evidence that monitoring methadone plasma concentration may be of benefit in dosage adjustment during methadone maintenance therapy for heroin (opiate) dependence. However, the kinetics of oral methadone are incompletely characterized. We attempted to describe the latter using a population approach combining intensive 57 h sampling data from healthy subjects with less intensive sparse 24 h data from opiate users.

METHODS

Single oral doses of rac-methadone were given to 13 drug-naive healthy subjects (7 men and 6 women) and 17 opiate users beginning methadone maintenance therapy (13 men and 4 women). Plasma methadone concentrations were measured by h.p.l.c. Kinetic analysis was performed using the P-Pharm software.

RESULTS

Comparison of kinetic models incorporating mono- or biexponential disposition functions indicated that the latter best represented the data. The improvement was statistically significant for the data from healthy subjects whether the full 57 h or truncated 24 h profiles were used (P<0.031 and P<0.024, respectively), while it was of borderline significance for the more variable data from opiate users (P=0.057) or for pooled (healthy subjects and opiate users) data (P=0.066). The population mean oral clearance of methadone was 6.9+/-1.5 s.d. l h(-1) (5.3+/-1.2 s.d. l h(-1) using 0-24 h data) in the healthy subjects. The results of separate analyses of the data from opiate users and healthy subjects were in contrast with those obtained from pooled data analysis. The former indicated a significantly lower clearance for opiate users (3.2+/-0.3 s.d. l h(-1), P<0.001); 95% CI for the difference = -3 to -6 l h(-1) and no difference in the population mean values of V/F (212+/-27 s.d. l and 239+/-121 s.d. l, P=0.15), while according to the latter analysis addiction was a covariate for V/F but not for oral clearance. A slower absorption of methadone in opiate users was indicated from the analysis of both pooled and separate data. The median elimination half-life of methadone in healthy subjects was 33-46 h depending on the method used to calculate this parameter.

CONCLUSIONS

Estimates of the long terminal elimination half-life of methadone (33-46 h in healthy subjects and, possibly, longer in opiate users) indicated that accurate measurement of this parameter requires a duration of sampling longer than that used in this study. Our analysis also suggested that parameters describing plasma concentrations of methadone after a single oral dose in healthy subjects may not be used for predicting and adjusting dosage in opiate users receiving methadone maintenance therapy unless coupled with feedback concentration monitoring techniques (for example Bayesian forecasting).

Using Peplau's theory in nurse-patient relations

In caring for a person suffering from depression, Peplau's theory of "Interpersonal Relations" was found to be both effective and representative of what psychiatric nurses do. Peplau's work, initially published in 1952, continues to make a major contribution to nursing knowledge and deserves the significance that it is being given in the 1990s. Below, a report on the learning experience for both the patient and the carer.

Defining the concept of care in the community

Care in the community has meant many different policies at different times. Recent policies have changed definitions but have done little to improve the lot of people affected by mental illness.

Hand-in-hand to the same goal. Quality assurance and research in nursing

1. The provision of good quality care is a right for all patients and the responsibility of all who deliver it. 2. Care based on knowledge that is validated by research can lead to improved practice and the further development of the service. 3. Patients now question the care they receive and expect an assurance of the quality of care they will receive when in hospital. 4. Quality assurance and the utilisation of research findings can enhance and improve patient care.

Know your patient. The importance of assessment in care delivery

Assessment is the first part of the nursing process, and thus forms the basis of the care plan. The essential requirement of accurate assessment is to view patients holistically and thus identify their real needs.

Use of 'very low-dose phenobarbital' to investigate compliance in patients on reducing doses of methadone (detoxification)

Incorporation of very low doses of phenobarbital into a methadone linctus has enabled us to monitor the compliance of 7 patients receiving a reducing dose of methadone (detoxification) for treatment for opioid addiction. By measuring both plasma phenobarbital and methadone we detected 4 patients who consumed extra illicitly obtained methadone during the detoxification regime. Treatment outcome was poor; 11 of the original 18 patients dropped out of treatment within 14 days and of those who remained, 4 patients relapsed and reabused illicit drugs and 2 returned to a fixed dose of methadone. Laboratory measurements were successfully used to detect poor methadone compliance.

A strategy to regain control: helplessness and depressive illness in women

The feelings of helplessness which accompany depression in many women have known psychological, physiological and sociological causes. By including patients in the decision-making process, nurses can help them begin to take control over their lives.

The influence of an academic representative on prescribing by general practitioners

1. The effect of providing information about medicines by a short 'sales' interview between individual general practitioners and an 'academic representative' on prescribing was investigated. 2. The promotional campaign was designed to encourage a rational approach to prescribing of non-steroidal anti-inflammatory agents in an intervention group of 101 general practitioners selected at random from the Leeds Family Practitioner Committee (FPC). The remaining general practitioners in the Leeds FPC acted as a reference group. 3. The prescribing data for each group for 5 months immediately prior to and 5 months following intervention were compared. 4. Intervention produced a significant increase (P less than 0.005) in the prescribing cost of ibuprofen, the non-steroidal promoted as first choice agent, which was sustained for at least 5 months. 5. Prescribing of the second choice agent, piroxicam, decreased in the reference group but not in the intervention group. 6. There was a decrease in the average prescribing cost of pounds 6.60 per doctor per month in the intervention group compared with the reference group.

The prediction of steady-state plasma phenobarbitone concentrations (following low-dose phenobarbitone) to refine its use as an indicator of compliance

1. A model for predicting the steady-state plasma concentration of phenobarbitone following low-dose phenobarbitone used as an indicator of compliance was derived using data for 10 healthy volunteers. 2. Each volunteer was given a single 30 mg oral dose of phenobarbitone and the pharmacokinetics were described. Subsequently, volunteers were given phenobarbitone 2 mg daily for 28 days and a further pharmacokinetic profile determined during and after this period. 3. An initial predicted estimate of steady-state plasma drug concentration was made using each volunteer's demographic details. This estimate was revised by Bayesian analysis using single timed samples (24, 48, 72 or 96 h) following the single dose. 4. The model was tested on a further 10 healthy volunteers given a single 8 mg dose and who were subsequently given 2 mg daily for 28 days. 5. The revised estimate of peak steady-state plasma phenobarbitone concentration utilising the 96 h post-single dose concentration (356 ng ml-1) was least biased (mean prediction error +/- 95% CI = 10.6 +/- 19.8 ng ml-1) and most precise (root mean square error +/- 95% CI = 28.3 +/- 19.0 ng ml-1). In all cases the peak or trough steady-state drug concentration was within 13% of the predicted value. 6. The model reflected compliance accurately in a further eight volunteers with simulated partial (two-thirds) compliance. 7. The use of a predictive model using Bayesian analysis to estimate expected steady-state plasma phenobarbitone concentrations could increase further the usefulness of low-dose phenobarbitone as an indicator of compliance.

Measuring compliance in methadone maintenance patients: use of a pharmacologic indicator to "estimate" methadone plasma levels

A quantitative indicator of compliance is not available for methadone--the drug of choice for the treatment of opioid addiction. We successfully used low-dose phenobarbital (a valid pharmacologic indicator) to measure compliance by incorporating the drug into the methadone medication of patients attending an addiction unit. Plasma phenobarbital and methadone concentrations were measured in 20 (11 clinic-based and 9 community-based) patients receiving long-term treatment with the phenobarbital level-to-dose ratio, together with interviews, to validate methadone measurements and to monitor compliance. Patients attending the unit on a daily basis and who consumed their medication in the clinic were substantially more compliant than community-based patients. Laboratory measurements of phenobarbital and methadone helped to identify the use of illicit methadone, as well as incorrect self-administration, such as the consumption of several days' dosage at one time.

Comparison of lisinopril versus atenolol for mild to moderate essential hypertension

The antihypertensive effects and safety profiles of lisinopril (10 to 40 mg) and atenolol (50 to 100 mg) were compared in a randomized, double-blind, parallel group trial in 144 patients with essential hypertension. After 8 weeks of therapy, seated blood pressure (BP) decreased by 26/15 mm Hg with lisinopril and by 19/14 mm Hg with atenolol. Lisinopril produced a greater reduction (p less than 0.05) in sitting systolic BP than did atenolol. Standing BP decreased by 25/15 mm Hg with lisinopril and by 19/14 mm Hg with atenolol. No important changes in hematologic and biochemical profiles were seen with either drug. Eleven patients, 7 receiving lisinopril and 4 receiving atenolol, were withdrawn because of adverse experiences; another 3 patients defaulted during treatment, 1 in the lisinopril group and 2 in the atenolol group. Both drugs were well-tolerated and are therefore suitable for first-line therapy in essential hypertension.

A comparison of a short half-life marker (low-dose isoniazid), a long half-life pharmacological indicator (low-dose phenobarbitone) and measurements of a controlled release 'therapeutic drug' (metoprolol, Metoros) in reflecting incomplete compliance by volunteers

1. Although, long half-life compounds appear to be more appropriate pharmacological indicators of compliance with treatment, short half-life markers or measurements of short half-life therapeutic drugs are frequently used. 2. We have compared the usefulness of low-dose phenobarbitone (a long half-life indicator), low dose isoniazid (a short half-life marker) and controlled release metoprolol (Metros) (a controlled release formulation of a short half-life 'therapeutic' drug) in seven volunteers with simulated partial (two thirds) compliance. 3. Detection of isoniazid metabolites in urine had an 83% sensitivity and 94% specificity for detecting ingestion within the previous 24 h and 100% sensitivity and 82% specificity for detecting ingestion within the past 6 h but gave no indication of the longer term pattern of compliance. 4. At 28 days (a time when steady-state would be obtained for all three drugs) phenobarbitone plasma levels were 70% (66-76%)--median and interquartile range--of the expected steady-state level if compliance had been complete. Corresponding figures for metoprolol were 82% (37-100%). 5. Measurement of phenobarbitone was much superior to isoniazid or metoprolol measurements in reflecting partial compliance over the previous 1 to 4 weeks.

What do patients and rheumatologists regard as an 'acceptable' risk in the treatment of rheumatic disease?

A questionnaire designed to ascertain the risk of adverse effects which patients with rheumatic conditions would accept for a particular therapeutic outcome was administered to 50 patients. The same questionnaire together with 'potted' histories of five of the patients was sent to 10 consultant rheumatologists. The willingness of both patients and doctors to risk side-effects varied with both the severity of the side-effect and the potential therapeutic benefit. Doctors were more willing than patients to risk death or serious disability (Wilcoxon, P less than 0.01) for a particular expected benefit. Doctors were also more willing to risk side-effects in treating seropositive rheumatoid arthritis than in treating non-articular rheumatism. No correlation was seen for patients between acceptable risk and diagnosis, pain or smoking habits. The risks which both groups stated they were willing to accept were less than those apparently associated with antirheumatic therapy. The results disagreed markedly with those of a previous study, demonstrating the importance of the methods used in this type of work.

Compliance in clinical trials

Compliance with treatment can be an important determinant of the outcome of clinical trials. To date there is no completely satisfactory method of measuring compliance and some of the most widely used methods are inadequate. The various methods of measuring compliance and how they have been applied to clinical trials are described, and improvements in the standard of the measurement and reporting of compliance in clinical trials are suggested.

Time to stop counting the tablets?

We attempted to assess compliance using both a pharmacologic indicator (low-dose phenobarbital) and a return tablet count in 225 patients who were taking part in three separate studies. There were 216 patients (96%) who kept a follow-up appointment after 28 days; 161 patients appeared to have good compliance (90% to 109%) by return tablet count. Of these 161 patients, 51 (32%) had plasma phenobarbital concentrations (corrected for dose and weight) that were less than 90% of the lowest value previously found in normal volunteers, which suggested poorer compliance. When compared with the age-related volunteer values, 77 (48%) had values that were less than 90% of the lowest volunteer value. There were 6 of 10 patients with apparently excessive (greater than or equal to 110%) compliance by return tablet count and 4 of 12 who failed to return their container who also had phenobarbital concentrations that were less than 90% of the lowest volunteer value. We concluded that return tablet count grossly overestimates compliance.

Lack of anticonvulsant tolerance with RU 32698 and Ro 17-1812

Possible development of anticonvulsant tolerance to three benzodiazepine receptor ligands was assessed in mice using an i.v. infusion of pentylenetetrazol as the convulsive stimulus. Extensive tolerance developed rapidly in the case of diazepam (0.35 mg/kg b.d. or 1.5 mg/kg b.d.). No significant tolerance was seen with the imidazopyrimidine derivative RU 32698 (9 mg/kg b.d.) or the partial agonist benzodiazepine Ro 17-1812 (1 mg/kg b.d.) These results provide further support for the hypothesis that partial agonists at the benzodiazepine receptor induce less tolerance than full agonists.

Patients' knowledge concerning their medications on discharge from hospital

Fifty patients were interviewed, on discharge from hospital, about their medications. Nine (18%) patients did not know, and a further four (8%) had inappropriate beliefs about why they were taking at least one of their discharge medications. Very few patients knew of significant side-effects which they might expect, or precautions which they should take, and over half did not know how long they were to continue taking their medicines. A small proportion was unable to read the bottle or open the container. Thus, even patients who, by virtue of an in-patient stay, have had a prolonged opportunity for education regarding their medicines have very little knowledge of their medicines upon discharge from hospital.

Disappointing results of increasing benzodiazepine dose after the development of anticonvulsant tolerance

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Use of a pharmacological indicator to monitor compliance with thyroxine

Poor compliance with medication is often suspected, but difficult to confirm. The compliance of fourteen newly diagnosed hypothyroid patients was assessed using both TSH levels and low-dose phenobarbitone as a pharmacological marker. The study confirms the value of phenobarbitone as an indicator of compliance over a protracted period and suggests that it could be used to differentiate under-treatment from poor compliance.

RO 16-6028, a benzodiazepine receptor partial agonist, does not exhibit anticonvulsant tolerance in mice

The development of anticonvulsant tolerance with RO 16-6028, a benzodiazepine receptor partial agonist, was assessed in mice using an i.v. infusion of pentylenetetrazol as the convulsive stimulus. In contrast to other benzodiazepines tested previously in this seizure model the anticonvulsant protection afforded by RO 16-6028 did not change significantly during 10 days treatment (2 mg/kg b.i.d.). This result supports the hypothesis that partial agonists at the benzodiazepine receptor may induce less tolerance and/or dependence than full agonists.

Can benzodiazepines be classified by characterising their anticonvulsant tolerance-inducing potential?

The development of anticonvulsant tolerance with three benzodiazepines was assessed in mice using a slow intravenous infusion of pentylenetetrazol as the convulsive stimulus. Chlordiazepoxide (12.5 mg/kg b.d.) and midazolam (0.75 mg/kg b.d.) induced a slowly evolving tolerance over 15 days whereas nitrazepam (0.6 mg/kg b.d.) induced a very marked rapid tolerance which developed no further during 6 days treatment. Tolerance appeared to be incomplete with all three benzodiazepines. Possible explanations for the differences in tolerance profile are discussed and an alternative basis for the classification of benzodiazepines is suggested.

Third nerve palsy due to posterior communicating artery aneurysm: the importance of early surgery

The value of early, direct aneurysm clipping in restoring third-nerve function after palsy associated with a posterior communicating artery aneurysm is assessed.

Low-dose phenobarbitone as an indicator of compliance with drug therapy

1 To assess the potential value of low-dose phenobarbitone (PB) as a marker of compliance we studied the relationship between plasma level of PB and dose (2-16 mg daily) following 3 or 4 weeks treatment in healthy volunteers (n = 26) and in-patient volunteers (n = 7). 2 Also, to simulate poor compliance, PB levels were measured in some volunteers following alternate-day (n = 6) or short-term (n = 5) treatment with similar doses. These levels, expressed as the level: dose ratios (LDRs), did not overlap with those obtained following 3 or 4 weeks of daily PB intake. 3 To evaluate the efficacy of this marker in patients taking other drugs we gave a group of out-patients (n = 24) compound tablets containing B vitamins and a small dose (16 mg) of PB; their compliance over 2-5 weeks was assessed both by measuring plasma levels of PB and residual tablet counting. 4 In the latter study, as well as providing absolute evidence of good compliance by many patients, the plasma levels of PB proved particularly valuable when non-compliant individuals 'forgot' to bring their residual tablets. 5 We suggest that phenobarbitone, in doses low enough to be non-sedative and non-enzyme inducing, is potentially useful as a pharmacological indicator of compliance with drug therapy.

N-desmethylclobazam: a possible alternative to clobazam in the treatment of refractory epilepsy?

The development of anticonvulsant tolerance during 10 days treatment with either clobazam or its principal metabolite, N-desmethylclobazam (NDMC), was compared in mice using an i.v. infusion of pentylenetetrazole as the convulsive stimulus. Subsequently the anticonvulsant activity of NDMC was assessed in patients with refractory epilepsy. In mice, a highly significant tolerance (P less than 0.001) developed to clobazam (10 mg kg-1 twice daily). During the same period, there was no significant change (P greater than 0.05) in the protection afforded by NDMC (40 or 80 mg kg-1 twice daily) although some reduction in anticonvulsant activity was apparent. NDMC (30 mg once daily) was given to nine patients with frequent complex partial and/or grand mal seizures who had become tolerant to the anticonvulsant effect of clobazam. Seven of the patients had been free from benzodiazepine therapy for at least 2 weeks, while the other two patients were switched directly from clobazam. Eight of the nine patients showed a favourable response to NDMC. In the seven who had been given a holiday from clobazam the response to NDMC was similar to the initial response to clobazam and was achieved at plasma NDMC concentrations in the same range as those seen during clobazam administration (1000-3000 ng ml-1). It is concluded that NDMC is active as an anticonvulsant in man and there is evidence from the animal studies to suggest that it may be preferable to clobazam.

Tolerance to the anticonvulsant effect of clonazepam in mice: no concurrent change in plasma concentration

Clonazepam was administered for 10 or more days on three different dose regimens (0.5, 0.25 and 0.08 mg kg-1 twice daily) to mice given pentetrazol by slow intravenous infusion. Plasma concentrations of clonazepam were assayed by high performance liquid chromatography. Tolerance developed to the anticonvulsant effect of clonazepam at all doses but was incomplete and could be overcome by increasing the dose. With the 0.5 and 0.25 mg kg-1 regimens there was no significant change in the drug plasma concentrations during development of tolerance; on the lowest dose, levels were below the limits of accurate detection. Anticonvulsant tolerance does not seem to be the result of a disturbance in clonazepam metabolism.

Benzodiazepine cross-tolerance in mice extends to sodium valproate

Slow intravenous infusion of pentylenetetrazol was used to measure the convulsive threshold in mice. The anticonvulsant effects of clobazam, clonazepam, diazepam, lorazepam, sodium phenobarbitone and sodium valproate were assessed in naive animals and compared with the effects of the same compounds in animals which had been pretreated (twice daily for 3 days) with one of the benzodiazepines or sodium valproate. Cross-tolerance was observed between all the benzodiazepines but not between benzodiazepines and sodium phenobarbitone. Animals pretreated with the benzodiazepines were cross-tolerant to valproate, but the converse was not true; nor did sodium valproate induce tolerance to itself.

Doctors' unawareness of the drugs their patients are taking: a major cause of overprescribing?

We studied the accuracy of both hospital and general practitioners' records of current drug treatment in consecutive patients who attended a general medical review clinic. Either the hospital or the general practitioner's records (obtained in a questionnaire), or both, were inaccurate for over 70% of 59 patients interviewed with their medicine. Most of the errors were due to patients taking drugs in addition to those shown in their records. Some of these were inappropriate, and many seemed unnecessary. It appears that neither hospital doctors nor general practitioners are fully aware which drugs their patients are taking, and this may contribute to overprescribing. We believe that considerable financial savings might be made if patients brought all their medicines to every consultation.