Decision-making using absolute cardiovascular risk reduction and incremental cost-effectiveness ratios: a case study.

BACKGROUND: Many clinical guidelines have adopted a multifactorial cardiovascular risk assessment to identify high-risk individuals for treatment. The Framingham risk chart is a widely used risk engine to calculate the absolute cardiovascular risk of an individual. Cost-effective analyses are typically used to evaluate therapeutic strategies, but it is more problematic for a clinician when faced with alternative therapeutic strategies to calculate cost effectiveness. AIM: We used a single simulated-patient model to explore the effect of different drug treatments on the calculated absolute cardiovascular risk. METHODS: The Framingham risk score was calculated on a hypothetical patient, and drug treatment was initiated. After every drug introduced, the score was recalculated. Single-exit pricing of the various drugs in South Africa was used to calculate the cost of reducing predicted cardiovascular risk. RESULTS: The cost-effective ratio of an antihypertensive treatment strategy was calculated to be R21.35 per percentage of risk reduction. That of a statin treatment strategy was R22.93 per percentage of risk reduction. U sing a high-dose statin, the cost-effective ratio was R12.81 per percentage of risk reduction. Combining the antihypertensive and statin strategy demonstrated a cost-effective ratio of R23.84 per percentage of risk reduction. A combination of several drugs enabled the hypothetical patient to reduce the risk to 14% at a cost-effective ratio of R17.18 per percentage of risk reduction. CONCLUSION: This model demonstrates a method to compare different therapeutic strategies to reduce cardiovascular risk with their cost-effective ratios.

An educational intervention to improve the quality of care of diabetic patients.

OBJECTIVE: As few studies have addressed intervention for in-hospital care of diabetes mellitus (DM) patients, we set out to investigate whether an educational intervention targeting doctors could improve the quality of care for diabetic patients. DESIGN: An observational interventional study conducted at Pretoria Academic Hospital, a tertiary care hospital. SUBJECTS: Doctors working in the Department of Internal Medicine were the subjects of two interventional sessions on diabetic care, and all diabetic patients admitted to the wards in the above Department were evaluated. OUTCOME MEASURES: A Diabetes Attitude Scale (DAS-3) and a Diabetes Practice Scale (DPS) were completed by each doctor before and after the interventional educational sessions. Data from diabetic patients in the wards were collected for 5 weeks before and 5 weeks after the interventional training, and these two sets of data were compared to measure the effect of the interventional training. RESULTS: Subscales of the DAS-3 showed an improvement, with a statistically significant improvement in attitude regarding seriousness of DM (P = 0.03), and a trend towards improvement in attitude regarding need for special training and patient autonomy. Most of the items on the DPS improved significantly (P < 0.05). CONCLUSIONS: A short educational intervention resulted in an improvement in attitude, knowledge and clinical management of diabetic patients.

National policy on testing for HIV in South Africa: an urgent need.

No National Policy exists in South Africa for the testing of persons who may be infected by HIV/AIDS. A Draft National Policy on Testing for HIV was published in the Government Gazette by the Minister of Health for commentary in December 1999. The policy provides for the following: circumstances under which HIV testing may be conducted; informed consent, pre-test and post-test counselling; and the interpretation of the policy. This policy will apply to persons who are able to give consent as well as to those who are legally entitled to give proxy consent to HIV testing. Testing with informed consent means that the individual has been made aware of, and understands, the implications of the test. "The vision which fueled our struggle for freedom; the deployment of energies and resources; the unity and commitment to common goals--all these are needed if we are to bring AIDS under control. Future generations will judge us on the adequacy of our response." President Nelson Mandela. DAVOS, 1996.

Further offences by discharged psychiatric patients--can somebody be held liable?

The decision to release a state patient who is unfit to stand trial and/or not criminally responsible, who had been committed to a mental institution in terms of the Criminal Procedure Act or who was held in terms of section 28 of the Mental Health Act, may have harmful or even fatal consequences. The multi-professional team at Oranje Hospital will only institute discharge procedures regulated in terms of section 29 of the Mental Health Act when it is of the opinion that a state patient's mental illness is stable and well-controlled and his clinical picture is such that he qualifies to be discharged. In this discussion focus will be placed on: a. the two discharge procedures applied in South Africa. b. four case studies which will be presented dealing with the observation period, admission, offence, diagnosis, treatment, hospitalisation, leave periods, discharge on certain conditions, re-admission and further offences. c. the question of whether the State may be held liable for the negligent or wrongful discharge or release of a state patient who subsequently commits a serious crime.

Criteria for fitness to stand criminal trial.

OBJECTIVE: To identify criteria whereby triability can be determined. DESIGN: Questionnaire survey. The final rating was decided on the basis of a structured psychiatric interview. SETTING: Oranje Hospital, Bloemfonteln. PARTICIPANTS: A total of 736 questionnaires was sent to 176 judges of the Supreme Court, 480 magistrates and 32 attorneys-general and state advocates in South Africa and Namibia, and 33 psychiatrists and 15 clinical psychologists working in forensic psychiatric units in South Africa. With the information from the completed questionnaires, rating criteria were compiled. The rating criteria were applied by means of a structured interview to 100 persons referred in terms of section 77(1) of the Criminal Procedure Act 51 of 1977. A multiprofessional psychiatric team was requested to evaluate the same 100 observandi independently. RESULTS: A total of 298 (40.5%) of the questionnaires were returned. From the data of the completed questionnaires, 19 legal items, 17 psychiatric items, 2 special laboratory tests and 2 psychosocial items were identified as the most important and clear diagnostic indications for the evaluation of triability. The similarity between the findings of the researchers and those of the multiprofessional psychiatric team was meaningful to 1% of significance. For the proper application of the criteria a cut-off point of 31 was determined. A score of 31 or higher therefore indicates that a patient is unfit to stand trial, while a score of less than 31 indicates triability. CONCLUSIONS: The application of the proposed final rating criteria as a single method of rating is at the very least just as reliable as the multiprofessional team in evaluating fitness to stand trial. The proposed criteria, used as a single rating instrument, are cost-effective in terms of time and staff, avoid unnecessary hospitalisation and ensure that mentally ill accused will have a fair trial.

Informed consent: research and the psychotic patient.

During the past few decades, western societies seem to have placed a particularly high premium on the individual's personal integrity and right to self-determination. Presently, obtaining a patient's consent is accepted as a prerequisite for the performance of any form of medical treatment, whether diagnostic or therapeutic in nature. A study was undertaken in various centres involved with clinical trials to compare the procedures used for obtaining informed consent from a psychotic patient. Although the study did not investigate the legal aspects related to consent and informed consent, it is necessary that one must be aware of these aspects when doing clinical trials.

The protection of personal and medical data--a call for confidentiality.

Personal data and privacy are increasingly being threatened by a boom in technological development--the replacement of conventional networks of communication with the perfected combination of computer and telecommunications. The subsequent high degree of transparency has the potential to damage the individual's right to 'informational self-determination'. The most common ways of unlawfully entering a computer data system, the reasons why an individual's information is treated as confidential and the ethical issues involved, international and local statutory instruments that protect such personal information, and ways to stop the outflow of personal information are discussed.

The creation and development of an instrument to determine fitness to stand trial.

A research team, consisting of a jurist and a psychologist, created and developed an instrument which could be used to effectively assess the fitness to stand trial of an accused person. A questionnaire was compiled and sent out to 736 members of both the legal and mental health professions. The information received from the response group was used to compile the fitness instrument. This instrument was applied to 100 observandi, committed to Oranje Hospital in terms of the Criminal Procedure Act, by way of a semi-structured interview. The same 100 observandi were evaluated by a multi-disciplinary team of the hospital and the results of the two groups were compared. This comparison showed a significant resemblance and it was concluded that the instrument could successfully be used as a single method of evaluating triability.

Legal status of the mentally disabled person in South African law.

Mental illness or insanity has a dramatic influence on a person's legal status. A person's status determines his or her competencies such as legal capacity, capacity to act, accountability and capacity to litigate. A mentally ill person is incapable of performing juristic acts; he or she is not capable of becoming a party to legal proceedings; is virtually incapable of committing a crime or being liable for a delict; etc. However, not all mentally ill persons are precluded from performing legal acts or, for that matter, giving valid consent to medical treatment. The reason being that status is factually determined according to the degree to which the mental illness is present at the time when the mentally ill person participates in the legal traffic. The measure of capability depends on the patient's intellectual and volitional capacities that will decide whether the patient can validly contract, litigate or consent to medical treatment. More specifically medical research of a non-therapeutic nature can only be carried out on mental patients who are capable of consenting thereto. This article endeavours to touch upon the different aspects of the mentally ill person's legal status.

Significance of adenosine deaminase activity and its isoenzymes in tuberculous effusions.

Adenosine deaminase (ADA) activity is increased in effusions caused by certain clinical conditions including tuberculosis and bacterial infections. In this study, the ADA isoenzyme patterns in tuberculous and parainfective effusions were investigated to determine the isoenzyme responsible for this increase in activity. Fifty-one tuberculous effusions and six parainfective effusions were investigated. All effusions had increased ADA activity (median values of 126 and 127 units/L, respectively). In the tuberculous effusions, ADA2 isoenzyme was found to be primarily responsible for total activity, with a median contribution of 88 percent. The ADA1 (both ADA1m and ADA1c isoenzymes) was the major isoenzyme in the parainfective effusions with a median contribution of 70 percent. The ADA2 isoenzyme activity most likely reflects monocyte-macrophage turnover or activity, while ADA1 probably originates from lymphocytes or neutrophils. It is therefore essential to determine the isoenzyme profile when interpreting ADA activity levels in effusions. The measurement of the individual isoenzymes will enhance the diagnostic utility of ADA activity determinations in pleural effusions.

An enzymatic assay of inorganic phosphate in serum using nucleoside phosphorylase and xanthine oxidase.

We have developed a new enzymatic assay for the determination of inorganic phosphate (Pi) in serum, using nucleoside phosphorylase (NP) and xanthine oxidase (XOD). Pi and inosine react to form hypoxanthine and ribose-1-phosphate. The hypoxanthine is oxidized to xanthine, which is further oxidized to uric acid. In these two reactions 2,6-dichlorophenol-indophenol (DCIP) is reduced to a colourless compound and the decrease in colour is measured spectrophotometrically at 600 nm. The assay is automated with an RA-XT analyser. The precision of the automated assay is acceptable (C.V. < 3.5%) and results are accurate and linear across a range of values from 0.2-2.5 mmol/l. The assay correlates well with molybdate methods carried out on SMAC III and RA-XT analysers (r values 0.99 and 0.98, respectively), and seems to be less prone to non-specific sample interference than the usual RA-XT method. The enzymatic assay described seems to be suitable for the routine determination of serum Pi.

Kinetic determination of serum adenosine deaminase.

A new kinetic method for the determination of serum adenosine deaminase (EC 3.5.4.4) is described, with adenosine as the substrate and nucleoside phosphorylase and xanthine oxidase as the reaction enzymes. Inosine is produced, which is converted to hypoxanthine. The hypoxanthine is oxidized to xanthine, which is further oxidized to uric acid. In these two reactions, blue 2,6-dichlorophenolindophenol is reduced to a colorless compound and the decrease in color is measured spectrophotometrically at 606 nm. The assay was automated by using a Cobas Mira analyzer. The automated assay had a CV of < 7%, and the calibration curve was linear from 10 to 120 U/L. The assay correlates well with an established method, based on detection of liberated NH3 with Berthelot's reaction. The reference interval (mean +/- 2 SD) was 14-34 U/L (mean 24 U/L, n = 84). The enzymatic method described is easily automated and seems to be suitable for the routine determination of adenosine deaminase in serum.

Serum adenosine deaminase: isoenzymes and diagnostic application.

Human adenosine deaminase (ADA; EC 3.5.4.4) consists of three isoenzymes: ADA1, ADA1+CP, and ADA2. We developed an electrophoretic technique to distinguish between these three isoenzymes. The isoenzyme pattern was studied in tissue and cell homogenates, as well as in serum from normal subjects and from patients with increased serum ADA who had either hepatitis, infectious mononucleosis, tuberculosis, pneumonia, rheumatoid arthritis, or acute lymphoblastic leukemia (ALL). The highest ADA activity was found in lymphocytes and monocytes. ADA2 could be detected only in monocytes (18% of total ADA activity). It was also the predominant isoenzyme in the sera of controls and all disease groups, except for ALL--the only condition evaluated that is not of an inflammatory nature. We conclude that serum ADA reflects monocyte/macrophage activity or turnover in most diseases studied. The exception is ALL, where serum ADA most probably originates from lymphocyte precursors.

Cooperation between experts in fitness proceedings.

The handling of the mentally ill offender involves the law as well as psychiatry and it is, therefore, essential that a good relationship exists between the jurist and the psychiatrist. The answering of questions of law by the courts needs the assistance and cooperation of mental health experts. This cooperation between the law and mental health professions is inevitable and necessary because the court is not an expert in the field of psychiatry. The duty of the psychiatric expert is to furnish the judge with necessary scientific criteria for testing the accuracy of the conclusions, so as to enable the court to form its own independent judgment by the application of these criteria to the facts proved in evidence.