Profiles of non-compliance with antituberculous therapy

Alternative Methods for Therapeutic Drug Monitoring and Dose Adjustment of Tuberculosis Treatment in Clinical Settings: A Systematic Review

BACKGROUND AND OBJECTIVE

Quantifying exposure to drugs for personalized dose adjustment is of critical importance in patients with tuberculosis who may be at risk of treatment failure or toxicity due to individual variability in pharmacokinetics. Traditionally, serum or plasma samples have been used for drug monitoring, which only poses collection and logistical challenges in high-tuberculosis burden/low-resourced areas. Less invasive and lower cost tests using alternative biomatrices other than serum or plasma may improve the feasibility of therapeutic drug monitoring.

METHODS

A systematic review was conducted to include studies reporting anti-tuberculosis drug concentration measurements in dried blood spots, urine, saliva, and hair. Reports were screened to include study design, population, analytical methods, relevant pharmacokinetic parameters, and risk of bias.

RESULTS

A total of 75 reports encompassing all four biomatrices were included. Dried blood spots reduced the sample volume requirement and cut shipping costs whereas simpler laboratory methods to test the presence of drug in urine can allow point-of-care testing in high-burden settings. Minimal pre-processing requirements with saliva samples may further increase acceptability for laboratory staff. Multi-analyte panels have been tested in hair with the capacity to test a wide range of drugs and some of their metabolites.

CONCLUSIONS

Reported data were mostly from small-scale studies and alternative biomatrices need to be qualified in large and diverse populations for the demonstration of feasibility in operational settings. High-quality interventional studies will improve the uptake of alternative biomatrices in guidelines and accelerate implementation in programmatic tuberculosis treatment.

Follow-up of compliance with tuberculosis treatment in children: monitoring by urine tests

This study was designed to follow up patient compliance by detection of antituberculous drugs in urine during the course of treatment. It was conducted in the Outpatient Clinic of Pediatric Infectious Diseases, Sisli Etfal Hospital (Istanbul, Turkey). In total, 45 children with pulmonary tuberculosis participated. Patients were seen twice in the first month and once a month thereafter during the 6-month course of treatment. The second urine of the day was collected at each visit. Urine was tested for isoniazid (INH), rifampicin (RIF), and pyrazinamide (PZA). In the presence of these drugs or their metabolites, the addition of certain chemicals caused a color change in the urine. On day 15 of treatment, urine tested positive for INH in 82% of patients, for RIF in 67%, and for PZA in 73%. At the end of the second month, the ratio of adherence was 96, 89, and 96% for each drug, respectively. All patients were found to be adherent at months 5 and 6. We recommend detection of antituberculous drugs in urine to assess compliance to treatment. Once the defaulting patients were identified, adherence was improved by repeatedly providing patient education throughout the treatment.

Low level of compliance with tuberculosis treatment in children: monitoring by urine tests

Patient compliance should be ensured in an effective tuberculosis control programme. We measured patient compliance by detecting antituberculous drugs in the urine of 237 outpatients receiving one to three antituberculous drugs. Positive controls were 20 hospitalised patients, supervised to receive isoniazid (INH), rifampicin (RIF) and pyrazinamide (PZA), and negative controls were not on any drugs. Among the 237 study patients, only 67% were found to be taking the appropriate treatment and 8% had taken none. We conclude that a remarkable number of patients (33%) were non-compliant with treatment. The detection of antituberculous drugs in the urine is a quick, simple and inexpensive means of measuring adherence to treatment. Unless directly observed therapy (DOT) is adopted, we recommend routine urine testing for antituberculous drugs to identify defaulting patients.

Antecedents of adherence to antituberculosis therapy

This correlational study identified antecedents of adherence to antituberculosis (anti-TB) therapy in a convenience sample of 62 English-speaking adults. From a demographic perspective, the study sample was similar to the referent population of TB patients in Georgia. A variety of parametric analyses revealed the following: The mean self-reported adherence score was 92.6% (SD = 3.3). Higher levels of self-reported adherence were associated with an annual income of $11,000 or more, education beyond high school, no current alcohol use, perceived support and absence of barriers to medication taking, strong intentions to adhere, and a high capacity for self-care. Those six variables accounted for 28% of adherence variance, F(6, 44) of 4.3, p = 0.0017. Additionally, belief in the usefulness and benefit of the medications was strongly correlated with intentions to adhere (r = 0.83, p < 0.001), and interpersonal aspects of care was significantly correlated with perceptions of medication utility (r = 0.65, p < 0.001), supports/barriers (r = 0.44, p < 0.001), intentions (r = 0.69, p < 0.001), and self-care (r = -0.42, p < 0.01). Persons who were diagnosed with both TB and human immunodeficiency virus (HIV) reported significantly lower adherence.

Childhood tuberculosis--problems ahead

Childhood tuberculosis (TB) is on the increase, both in developing countries and in the UK. Children cannot usually be diagnosed as having TB by sputum microscopy and culture alone, so millions of children are destined to die of undiagnosed TB in poor countries. Drug resistance is likely to affect a greater proportion of TB cases in children, because they have been recently infected by adults. Whilst BCG vaccination can protect against miliary TB and TB meningitis, it will not interrupt the chain of transmission. HIV co-infected mothers are capable of passing congenital TB to their children.

Treatment and prevention of multidrug-resistant tuberculosis

Multidrug-resistant tuberculosis (MDRTB), which is defined as combined resistance to isoniazid and rifampicin, is a 'man-made' disease that is caused by improper treatment, inadequate drug supplies or poor patient supervision. Patients with MDRTB face chronic disability and death, and represent an infectious hazard for the community. Cure rates of 96% have been achieved but require prompt recognition of the disease, rapid accurate susceptibility results, and early administration of an individualised re-treatment regimen. Such regimens are usually based on a quinolone and an injectable agent (i.e. an aminoglycoside or capreomycin) supplemented by other 'second-line' drugs. This therapy is prolonged (e.g. 24 months), expensive, and has multiple adverse effects. Prevention of MDRTB is therefore of paramount importance. The World Health Organization (WHO) has recommended a multifaceted programme, known by the acronym DOTS (directly observed therapy, short-course), that promotes effective treatment of drug-susceptible TB as the prime method of limiting drug resistance. DOTS was part of a successful MDRTB control programme in New York City, which also included treatment of prevalent MDRTB cases, streamlined laboratory testing, effective infection control procedures and wider application of screening and preventive therapy (although the optimal chemotherapy for MDRTB infection remains undefined). Industrialised countries have the resources to treat patients with MDRTB and to mount these extensive control programmes. Unfortunately, MDRTB is also prevalent in Asia, South America and the former Soviet Union. First world countries have a vested interest, as well as a moral responsibility, to assist in controlling MDRTB in these 'hot spots'.

Treatment compliance in adults with cystic fibrosis

BACKGROUND

The study comprised three interrelated aims: (1) to ascertain (a) patient compliance with physiotherapy, exercise, enzyme and vitamin regimens, (b) how compliance was perceived by patients, and (c) the reasons for poor compliance (2) to identify demographic and clinical variables associated with compliance; and (3) to determine how accurately patient compliance can be predicted by carers.

METHODS

Demographic and medical history data were obtained from medical records and a patient questionnaire. The data obtained included age, sex, employment status, inpatient or outpatient status, frequency of contact with the clinic, age at diagnosis, and the number of years practising physiotherapy. Measures of clinical status, including FEV1 and FVC percentage predicted, Shwachman score, and 24 hour sputum weight were recorded before completion of the questionnaire. The questionnaire, administered by a psychologist, assessed the reported degree of patient compliance, their perception of compliance, and their reasons for poor compliance.

RESULTS

Sixty patients participated in the study and 51/60 and 41/55 patients were considered compliant with enzyme and exercise therapies, respectively. Compliance was lower with physiotherapy (32/60) and vitamin treatment (21/45). Patients reporting immediate benefits following exercise and physiotherapy were more compliant than those reporting no improvement. The perception by patients that compliance was sufficient ("about right") was physiotherapy 67%, exercise 37%, enzymes 78%, and vitamins 9%. Compliance was not influenced by demographic details nor by severity of disease, although patients producing large amounts of sputum and receiving help with physiotherapy were more compliant with physiotherapy. The physiotherapist and physician judged correctly the degree of compliance with physiotherapy in 83% and 75% of cases, respectively, and with exercise in 68% and 67% of cases, respectively.

CONCLUSIONS

The reported degree of compliance and reasons for poor compliance were treatment specific. Demographic and disease severity variables were not associated with compliance. Those involved in the care of patients with cystic fibrosis were able to predict patient compliance.

When tuberculosis treatment fails. A social behavioral account of patient adherence

Several conclusions about measuring adherence can be drawn. Probably the best approach is to use multiple measures, including some combination of urine assays, pill counts, and detailed patient interviews. Careful monitoring of patient behavior early in the regimen will help predict whether adherence is likely to be a problem. Microelectronic devices in pill boxes or bottle caps have been used for measuring adherence among patients with tuberculosis, but their effectiveness has not been established. The use of these devices may be particularly troublesome for some groups such as the elderly, or precluded for those whose life styles might interfere with their use such as the homeless or migrant farm workers. Carefully designed patient interviews should be tested to determine whether they can be used to predict adherence. Probably the best predictor of adherence is the patient's previous history of adherence. However, adherence is not a personality trait, but a task-specific behavior. For example, someone who misses many doses of antituberculosis medication may successfully use prescribed eye drops or follow dietary recommendations. Providers need to monitor adherence to antituberculosis medications early in treatment in order to anticipate future problems and to ask patients about specific adherence tasks. Ongoing monitoring is essential for patients taking medicine for active tuberculosis. These patients typically feel well after a few weeks and either may believe that the drugs are no longer necessary or may forget to take medication because there are no longer physical cues of illness. Demographic factors, though easy to measure, do not predict adherence well. Tending to be surrogates for other causal factors, they are not amenable to interventions for behavior change. Placing emphasis on demographic characteristics may lead to discriminatory practices. Patients with social support networks have been more adherent in some studies, and patients who believe in the seriousness of their problems with tuberculosis are more likely to be adherent. Additional research on adherence predictors is needed, but it should reflect the complexity of the problem. This research requires a theory-based approach, which has been essentially missing from studies on adherence and tuberculosis. Research also needs to target predictors for specific groups of patients. There is clear evidence of the effect on adherence of culturally influenced beliefs and attitudes about tuberculosis and its treatment. Cultural factors are associated with misinformation about the medical aspects of the disease and the stigmatization of persons with tuberculosis. Culturally sensitive, targeted information is needed, and some has been developed by local tuberculosis programs.(ABSTRACT TRUNCATED AT 400 WORDS)

Factors associated with compliance in treatment of tuberculosis

The most important cause of failure of antituberculosis therapy is that the patient does not take the medication as prescribed. To assess this problem, a retrospective review was conducted, using medical and nursing records, of adult patients treated at the tuberculosis clinic of the Montreal Chest Hospital in 1987-1988. In all, 352 patients were identified, of whom 59% were judged to have completed therapy. Completion of therapy was recorded in 92% of those with culture-positive disease, 76% of those with active but culture-negative disease and 54% among the 300 prescribed preventive therapy (P < 0.001). Compliance with preventive therapy was highest among those who had been in contact with an active case, and lowest among those identified through a workforce screening survey (P < 0.01). At the time of the first follow-up visit, patients identified to have suboptimal compliance were more likely to fail to complete therapy (P < 0.001). Compliance was higher among those initially hospitalized, those assessed to have better understanding (P < 0.05), those prescribed 6-9 rather than 12 months of therapy (P < 0.01), and those who returned for follow-up within 4 weeks of initiation of therapy (P < 0.01). Compliance could be improved by enhancing patient understanding, closer follow-up, and shorter therapy, particularly for those at lower risk of reactivation. As well, additional compliance enhancing interventions can be targeted to those patients with suboptimal compliance who can be accurately identified early in the course of therapy.

Inter-relations between relapses, drug regimens and compliance with treatment in tuberculosis

The inter-relationships between relapse, treatment regimen and compliance in 1009 patients treated for tuberculosis between 1978 and 1987 are reported. Multiple linear logistic regression using relapse as the dependent variable was used because of the complex relationships between treatment, compliance, age and calendar year of treatment. Compliance (P less than 0.0001) was the major determinant of relapse, but age (P = 0.047) was also significantly associated. Relapse was not related to sex, site of disease, ethnic group or the presence of multiple disease sites. Although the regimen given, the total duration of treatment and treatment with or without pyrazinamide were not statistically associated with relapse, pyrazinamide containing regimens were associated with better compliance. Compliance was best in those aged 60 years and over and worst in those aged 15-29 years. Some of the non-compliance leading to relapse was only uncovered by close Health Visitor surveillance and not by the physician supervising treatment, emphasizing the important role of field staff in patient follow-up.

Patient compliance with tuberculosis treatment in Ghana: factors influencing adherence to therapy in a rural service programme

In Agogo Hospital in the hills of Ashanti, Ghana, default and cure rates among 569 consecutive sputum-smear positive pulmonary tuberculosis (PTB) patients registered between 1984 and 1987 in a rural ambulatory non-supervised service program were analysed. Female gender, shorter home-to-clinic distances and younger age were significantly associated with higher cure and lower default rates. Within the district where liaison health workers paid home visits to PTB patients, the home-to-clinic distance effect on default was overruled by the effect of follow-up. Data from two surveys held in 1985 and 1987, among 68 and 49 PTB patients respectively, revealed that many patients visited healing churches but few admitted to having consulted traditional healers; that financial expenses for transport outweighed hospital charges; that lower educational levels were not associated with poorer compliance to therapy and that health education had improved significantly over the 2-year-period. It is concluded that intervention with liaison health workers and simple health education results in improved outcome in rural service tuberculosis programme.