The utilisation and economic evaluation of antibiotics prescribed in primary care.

This was an observational study of efficacy and resource utilisation over three years in a cohort of 917 patients who received at least one prescription for an oral antibiotic between January and March 1989 in a large rural primary care health centre in Tayside, Scotland. Three thousand, six hundred and sixty three prescriptions were issued (2286 to females) for; 1502 upper respiratory tract infections, 419 lower respiratory tract infections, 441 urinary tract infections, 177 skin and soft tissue infections, 97 gynaecological infections, 103 cases of acne and 71 other infections. Excluding acne, 14% of infections required more than one antibiotic to achieve a successful outcome. The highest success rates for antibiotics were amoxycillin (92%) and penicillin V (92%) in upper respiratory tract infections, erythromycin (90%) in lower respiratory tract infections and co-trimoxazole (83%) in urinary tract infections. The most cost-effective antibiotics were penicillin V for upper respiratory tract infection, erythromycin for lower respiratory tract infection and co-trimoxazole for urinary tract infection. Varying the value placed on general practitioners' time did not change the rank order of antibiotic cost-effectiveness. The efficacy and cost-effectiveness of the treatment of acute infections in primary care varies considerably with the antibiotic used as first choice. More expensive antibiotics might be justified in cost-effectiveness terms if they had high cure rates in clinical practice.

Primary non-compliance with prescribed medication in primary care.

OBJECTIVE: To determine the rate of patients not redeeming their prescriptions (primary noncompliance) and assess the factors influencing this. DESIGN: Observational study comparing copies of prescriptions written by general practitioners with those dispensed by pharmacists and subsequent case record review. SETTING: A large rural general practice in Tayside. SUBJECTS: All 4854 patients who received prescriptions (20,921) written between January 1989 and March 1989. MAIN OUTCOME MEASURES: The rate of non-redemption of prescriptions. RESULTS: Seven hundred and two patients (14.5%) did not redeem 1072 (5.2%) prescriptions during the study period, amounting to 11.5% of men and 16.3% of women. Non-redemption was highest in women aged 16-29 (27.6% of women) and men aged 40-49 (18.3% of men). Of prescriptions issued to women for oral contraceptives 24.8% were not redeemed during the study period. In those who redeemed prescriptions 17% were not exempt from prescription charges compared with 33% of patients who failed to redeem them. The non-redemption rate was highest for prescriptions issued at the weekends, although this was a small proportion of all prescribing. Prescriptions issued by trainee general practitioners were also less likely to be redeemed. CONCLUSIONS: Non-redemption varies with age, sex, general practitioner, exemption status, and with day of the week the prescription was written. Observational studies of drug exposure can be more accurately estimated from dispensing rather than prescribing data.

The risks of symptomatic vaginal candidiasis after oral antibiotic therapy.

It is generally accepted that antibiotic use can result in vaginal fungal overgrowth, although evidence estimating the extent to which this causes symptomatic vaginitis is scant. In a study using the prescription of vaginal antifungal preparations as a surrogate measure of vaginal candidiasis, a cohort of women taking antibiotics had a higher incidence of vaginal candidiasis after antibiotic exposure than beforehand (relative risk 2.3; 95% confidence interval 1.9-3.0); this risk was highest in those aged 36-40 years (RR 6.0, 95% CI 2.9-12.5). The attributable risk was highest among those who were taking cephalosporins (AR 12.8%, 95% CI 9.1-16.5). In a case-control study, comparing previous antibiotic exposure among women using vaginal antifungal agents and matched controls, antibiotic exposure was higher among those using vaginal antifungal agents during the previous 28 days, with an odds ratio of 5.5 (95% CI 3.8-7.9).

Echocardiography in chronic heart failure in the community.

A total of 128 patients from a single practice population who were receiving loop diuretics for treatment of presumptive cardiac failure were identified from prescribing data captured by the Medicines Monitoring Unit. A subgroup of 78 patients underwent echocardiography to determine the prevalence of true left ventricular systolic dysfunction in this population and the validity of the diagnosis of cardiac failure in primary care. A further 50 patients were studied to assess the workload generated by these patients for both primary health care and hospital services. The estimated prevalence of left ventricular systolic dysfunction was 0.84%, whereas 1.6% of the population received loop diuretics for this indication. A false-positive diagnosis occurred in 47% and was more likely in females (73%) than males (37%). Of all consultations 79% were seen by GPs, 14% as hospital out-patients and 7% as in-patients. Within the hospital general physicians have most contact with these patients. In summary chronic heart failure is common within the community, although the false-positive rate for diagnosis of this condition is high. GPs and general physicians treat the majority of these patients and should therefore receive continuing education regarding recent advances in this area. Echocardiography should be performed early in the management of all patients suspected of having cardiac failure.