Browsing by Author "Williams, Z."

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    Risk factors for near-fatal asthma : a case-control study in a western cape teaching hospital
    (Health & Medical Publishing Group, 2002) De Klerk, A.; Van Schalkwyk, E.; Williams, Z.; Lee, W.; Bardin, P.
    Background and objectives. To evaluate risk factors for asthma death such as access to health care, over-use of β2-agonists or under-use of inhaled corticosteroids in the Western Cape (WC) population, using near-fatal asthma (NFA) as a surrogate marker. Subjects and methods. Patients with NFA (cases) admitted to a WC teaching hospital were compared with patients with acute asthma in a case-control study using a structured questionnaire, clinical examination, arterial blood gas measurements, chest radiograph and pulmonary function measurements. Results. Sixteen patients with NFA (cases) and 55 with acute asthma (controls) were prospectively enrolled. Duration of asthma, gender, smoking status and ethnicity were similar. Cases had significantly more previous mechanical ventilation (P < 0.05) and a trend towards more previous intensive care unit (ICU) admissions. No significant differences were found in primary health care variables. Conclusion. Our study demonstrates that patients with NFA constitute a significant number of emergency room (ER) admissions for acute asthma (30%) in our population. Similar to other studies, there was a trend for NFA toward more previous ICU admissions and mechanical ventilation. Relative under-use of β2-agonists the day before admission and fewer ER visits during the previous year in the NFA group, suggests an impaired perception of the severity of disease or a more rapid onset of symptoms. Negative factors such as inability to access health care or lack of medication supply were similar in both groups. The challenge remains to identify and manage high-risk patients effectively.
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    Therapeutic equivalence study of two formulations (innovator v. generic) of beclomethasone dipropionate in adult asthmatic patients
    (Health & Medical Publishing Group, 2001) Nell, H.; Louw, C. M.; Cyster, H.; Williams, Z.; Bardin, P. G.; Joubert, J. R.
    Objective. To study the therapeutic equivalence of two formulations (innovator v. generic) of beclomethasone dipropionate (BDP) 400 μg twice daily administered per metered dose inhaler (MDI), in adults with moderate to severe asthma. Methods. A double-blind randomised parallel-group trial was performed with a 2-week run-in and an 8-week treatment period. Thirty-six symptomatic adult asthmatics on a mean daily dose of 750 μg inhaled corticosteroids during run-in, a mean forced expiratory volume in 1 second (FEV1) of 70% predicted normal and a mean histamine concentration provoking a 20% reduction in FEV1 (histamine PC20) of 0.11 mg/l were randomised to one of the two treatment groups. Primary variables were morning peak expiratory flow (mPEF), FEV1 and histamine PC20. Secondary variables were β2-agonist use, symptom score and nocturnal awakening. The Schuirmann two one-sided tests procedure was used for the statistical analysis. Ninety-five per cent confidence intervals (CIs) were calculated for the differences in means. Results. The mean differences end of treatment to baseline for the two formulations (Becotide and Beclate) respectively were: mPEF 5.6 l/min (CI-16.4 - 27.6) and -22.3 l/min (CI-35.6 - -9); FEV1 -2.9% (CI -11 - 5.2) and 0.2% (CI-4.8 - 5.2); Histamine PC20 -0.04 mg/ml (CI -0.15-0.06) and 0.02 mg/ml (CI -0.37 - 0.4). Changes in clinical variables were not conclusive. The mean differences with CIs for primary variables were contained within the limits set for equivalence. The sample size was sufficient to differentiate the groups for mPEF, but this was not of clinical significance. Conclusion. After 8 weeks of treatment the two formulations of BDP, delivered by MDI through a large-volume spacer, were therapeutically equivalent in moderate-to-severe asthmatic adults.