Adherence to medication among chronic patients in Middle Eastern countries: review of studies

This paper reviewed studies that have investigated adherence to medication among patients with chronic conditions in Middle Eastern countries. A comprehensive literature search yielded 19 relevant studies. These focused on the extent and predictors of nonadherence to medication across different conditions, including hypertension, chronic obstructive pulmonary disease, asthma, diabetes, depression, schizophrenia and epilepsy. Estimated rates of nonadherence to medication ranged from 1.4% to 88%. This review confirms the existence of nonadherence as a problem among patients with chronic diseases and examines our understanding about the reasons and variables affecting patients' adherence to their medication in the Middle Eastern countries. However, the studies employed a wide range of methods, sometimes with limitations. Further work to determine the prevalence and causes of patients' nonadherence to medication in Middle Eastern countries is needed in order to recommend the best interventions to improve adherence.

Cessation of attention deficit hyperactivity disorder drugs in the young (CADDY)--a pharmacoepidemiological and qualitative study

OBJECTIVES

To estimate the prevalence of attention deficit hyperactivity disorder (ADHD) pharmacological treatment, and its demographic and clinical details, and to estimate the proportion of patients in the target group who stopped ADHD treatment and investigate possible factors for continuation or cessation of treatment.

DESIGN

A pharmacoepidemiological study using an automated database and a qualititative study using patient interviews. Part 1 was a pharmacoepidemiological study that provided accurate data on use and cessation of ADHD drugs. Part 2 was an in-depth interview study to investigate the reasons, processes and outcomes of treatment cessation.

SETTING

Part 1: primary care using the General Practice Research Database (GPRD). Part 2: secondary and tertiary care paediatric clinics, child and adolescent mental health and adult mental health clinics in London, Nottingham, Dundee and Liverpool.

PARTICIPANTS

Part 1: patients were 15-21 years old during the study period (1 January 2001 and 31 December 2004), had at least one prescription for methylphenidate, dexamfetamine or atomoxetine and had at least 1 year of research-standard data available in the GPRD. Part 2: patients fulfilled Part 1 criteria, had a diagnosis of ADHD as detected by a predefined algorithm and had been treated with methylphenidate, dexamfetamine or atomoxetine for at least 1 year. Child and adolescent psychiatrists, adult psychiatrists and paediatricians involved in the treatment of young people with ADHD were also interviewed as part of the study.

RESULTS

Part 1: prevalence of prescribing averaged across all ages increased eightfold, from 0.26 per 1000 patients in 1999 to 2.07 per 1000 patients in 2006. The increase in prevalence in the younger patients was less evident in the older patients. Prevalence in 15-year-old males receiving a study drug prescription increased from 1.32 per 1000 patients in 1999 to 8.31 per 1000 patients in 2006, whereas the prevalence in 21-year-olds rose from 0 per 1000 patients in 1999 to 0.43 per 1000 patients in 2006. Survival analysis showed that the rate of treatment cessation largely exceeded the estimated rate of persistence of ADHD. The reduction in prescribing was most noticeable between 16 and 17 years of age. Kaplan-Meier analysis showed that approximately 18% of patients restarted treatment if they had stopped treatment after the age of 15. Patients who restarted treatment were more likely to restart within the first year following treatment cessation. Part 2: the Child Health and Illness Profile (CHIP) was chosen as the quality of life questionnaire for the Part 2 study because the CHIP-CE scale has been validated in children with ADHD in the UK. Because of the age range of participants, the adolescent version (CHIP-AE) was administered to patients after interview. Of the 15, a total of nine patients finished the questionnaire. Interviews showed that although some young people felt able to cope after stopping medication, others felt the need to restart to control symptoms. Some patients had difficulty re-engaging with services and clinicians recognised the lack of services for young adults. Patients continuing on treatment considered cessation as an option for the future, but were concerned about the process of stopping and its impact on behaviour.

CONCLUSIONS

Part 1 study demonstrated that the prevalence of prescribing by GPs to patients with ADHD dropped significantly from age 15 to 21. The fall in prescribing was greater than the reported age-related decrease in symptoms, raising the possibility that treatment is prematurely discontinued in some young adults where ADHD symptoms persist. Part 2 of the study identified that some young adults had difficulty in obtaining treatment after discharge from paediatric services. Future work should include randomised placebo-controlled trials into long-term treatment with stimulants, particularly methylphenidate.

General practitioners' attitudes to assessment of genetic risk of common disorders in routine primary care

In 2003, the UK Department of Health set out the genetics white paper, a plan for action and investment with particular emphasis on integration of genetic health care into primary care. Since the delivery of the genetics white paper, there has been little exploration of UK primary care doctors' attitudes towards extending their role to include provision of routine genetics services. We explored explore general practitioners' (GPs) attitudes towards provision of genetic health care including routine family history screening and familial risk assessment for common disorders in primary care using a quantitative, evaluative postal survey. Only 25% (797 of 3160) of the GPs returned a completed questionnaire. Although 32% of GPs supported collection of family history information and 41.5% familial risk assessment, 18% were not willing to offer these services even if training is provided. Of the GPs, 50% stated they recognized when referral to genetics services is appropriate, although 43% felt unprepared to collect family history or assess familial risk. Lack of training within the last 3 years was a significant predictor of feeling unprepared to undertake these activities (OR = 2.53,p = 0.012). A substantial group of GPs remain unprepared or unwilling to provide genetic health care. GPs' attitudes to delivery of genetic health care are significantly influenced by factors such as a lack of evidence of the direct benefits to patients, local guidelines and specialist services. These factors need addressing if delivery of genetic health care is to be incorporated into routine primary care.

Monte Carlo Simulation of Carboxylic Acid Phase Equilibria

Configurational-bias Monte Carlo simulations were carried out in the Gibbs ensemble to generate phase equilibrium data for several carboxylic acids. Pure component coexistence densities and saturated vapor pressures were determined for acetic acid, propanoic acid, 2-methylpropanoic acid, and pentanoic acid, and binary vapor-liquid equilibrium (VLE) data for the propanoic acid + pentanoic acid and 2-methylpropanoic acid + pentanoic acid systems. The TraPPE-UA force field was used, as it has recently been extended to include parameters for carboxylic acids. To simulate the branched compound 2-methylpropanoic acid, certain minor assumptions were necessary regarding angle and torsion terms involving the -CH- pseudo-atom, since parameters for these terms do not exist in the TraPPE-UA force field. The pure component data showed good agreement with the available experimental data, particularly with regard to the saturated liquid densities (mean absolute errors were less than 1.1%). On average, the predicted critical temperature and density were within 1% of the experimental values. All of the binary simulations showed good agreement with the experimental x-y data. However, the TraPPE-UA force field predicts saturated vapor pressures of pure components that are larger than the experimental values, and consequently the P-x-y and T-x-y data of the binary systems also deviate from the measured data.

Range of self-tests available to buy in the United Kingdom: an Internet survey

We aimed to describe the availability in the United Kingdom of self-tests that are used to diagnose or screen for conditions without involving a health professional. A systematic Internet search identified 104 unique self-tests related to 24 named conditions including cancers, chronic conditions and infections. These self-tests require various samples including blood obtained using a lancet. The samples are processed at home with results available in minutes or sent to a laboratory for processing with results returned to the individual by e-mail or post. Prices per self-test and condition range from < Pounds 1 to Pounds 76. Self-tests are readily available, and further work is needed to assess their impact.

Genetic variation in resistance to repeated infections with Heligmosomoides polygyrus bakeri, in inbred mouse strains selected for the mouse genome project

Since the publication of the mouse genome, attention has focused on the strains that were selected for sequencing. In this paper we report the results of experiments that characterized the response to infection with the murine gastrointestinal nematode Heligmosomoides polygyrus of eight new strains (A/J, C57BL/6, C3H, DBA/2, BALB/c, NIH, SJL and 129/J), in addition to the well-characterized CBA (poor responder) and SWR (strong responder) as our controls. We employed the repeated infection protocol (consisting of 7 superimposed doses of 125L3 each administered at weekly intervals, faecal egg counts in weeks 2, 4 and 6 and assessment of worm burdens in week 6) that was used successfully to identify quantitative trait loci for genes involved in resistance to H. polygyrus. SWR, SJL and NIH mice performed indistinguishably and are confirmed as strong responder strains to H. polygyrus. CBA, C3H and A/J mice all tolerated heavy infections and are assessed as poor responders. In contrast, DBA/2, 129/J and BALB/c mice performed variably between experiments, some tolerating heavy worm burdens comparable to those in poor responders, and some showing evidence of resistance, although only in one experiment with female 129/J females and one with female BALB/c was the pattern and extent of worm loss much like that in SWR mice. Because the genetic relationships between six of the strains exploited in this study are now well-understood, our results should enable analysis through single nucleotide polymorphisms and thereby provide more insight into the role of the genes that control resistance to H. polygyrus.

Evidence of piezoelectric resonance in isolated outer hair cells

Our results demonstrate high-frequency electrical resonances in outer hair cells (OHCs) exhibiting features analogous to classical piezoelectric transducers. The fundamental (first) resonance frequency averaged f(n) approximately 13 kHz (Q approximately 1.7). Higher-order resonances were also observed. To obtain these results, OHCs were positioned in a custom microchamber and subjected to stimulating electric fields along the axis of the cell (1-100 kHz, 4-16 mV/80 microm). Electrodes embedded in the side walls of the microchamber were used in a voltage-divider configuration to estimate the electrical admittance of the top portion of the cell-loaded chamber (containing the electromotile lateral wall) relative to the lower portion (containing the basal plasma membrane). This ratio exhibited resonance-like electrical tuning. Resonance was also detected independently using a secondary 1-MHz radio-frequency interrogation signal applied transversely across the cell diameter. The radio-frequency interrogation revealed changes in the transverse electric impedance modulated by the axial stimulus. Modulation of the transverse electric impedance was particularly pronounced near the resonant frequencies. OHCs used in our study were isolated from the apical region of the guinea pig cochlea, a region that responds exclusively to low-frequency acoustic stimuli. In this sense, electrical resonances we observed in vitro were at least an order of magnitude higher (ultrasonic) than the best physiological frequency of the same OHCs under acoustic stimuli in vivo. These resonance data further support the piezoelectric theory of OHC function, and implicate piezoelectricity in the broad-band electromechanical behavior of OHCs underlying mammalian cochlear function.

An in vitro larval motility assay to determine anthelmintic sensitivity for human hookworm and Strongyloides species

With the implementation of programs to control lymphatic filariasis and soil-transmitted helminths using broad spectrum anthelmintics, including albendazole and ivermectin, there is a need to develop an in vitro assay for detection of drug resistance. This report describes an in vitro assay for measuring the effects of ivermectin and benzimidazoles on the motility of larvae of the hookworm species Ancylostoma ceylanicum, A. caninum, and Necator americanus, and Strongyloides species including Strongyloides stercoralis, and S. ratti. A dose-response relationship was demonstrated with each of the parasite species, with distinct differences observed between the various species. In pilot field testing of the assay with N. americanus larvae recovered from human fecal samples, a dose-response relationship was observed with ivermectin. While the assay has demonstrated the ability to determine drug responsiveness, its usefulness in resistance detection will require correlation with the clinical outcome among individuals infected with parasite strains showing different drug sensitivities.