Cost Evaluation of Commonly Prescribed Antihypertensive Drugs and the Pattern of Prescription among Doctors in the Lagos University Teaching Hospital

Pharmacological anti-hypertensive prescriptions of 600 randomly selected mild to moderate hypertensive patients were reviewed for 3 years in four Clinics of the Lagos University Teaching Hospital namely Cardiology, Endocrine, Nephrology and Neurology Clinics. Calcium channel blockers were the most frequently prescribed drugs (24.8%) followed by Angiotensin converting enzyme inhibitors (12.5%). Others included combined Amiloride/Hydrochlorothiazide (Co-amilozide) (10.6%), Alpha methyl dopa (10%), Beta Blockers (8.5%), combination of Co-amilozide and Alpha methyl dopa (6.8%), Co-amilozide,Calcium channel/Beta blockers (6.0%) etc. Brand name prescription was predominantly high in all the four Clinics (Cardiology 87.4%, Endocrine - 86.8%, Nephrology 74.6% and Neurology 87.9%) as compared to low generic prescription. The overall Brand name prescription was (83.4%) compared with Generic of (16%). The monthly cost difference between Generic anti-hypertensive single drug treatment and Brand named single drug treatment was between N500.00 to N600.00. It was concluded that the prescribing of the new generation drugs i.e. Calcium channel blockers, ACE inhibitors with supposedly little or no metabolic side effects is a new trend which should be scientifically evaluated vis--vis cost effectiveness and adverse drug reaction. It was also concluded that generic prescription should be encouraged among prescribers to lessen the financial burden of patients because drugs marketed under generic names are usually cheaper than those with brand names. Key words: Brand, Generic,Prescription, Antihypertensives,Cost. [Nig. Jnl Health & Biomedical Sciences Vol.1(2) 2002: 68-70

Changes in plasma osmolality and anion gap: potential predictors of impending mortality during maintenance dialysis

Background: Chronic kidney disease (CKD) is the 4 commonest cause of death in Nigeria. It affects the most economically productive age group. Many patients in stage 5 CKD are treated with haemodialysis which involves the movement of electrolytes and osmotic molecules from one body compartment to another, resulting in osmotic and anion-gap changes. These changes may be related to mortality in patients on haemodialysis.Objective: To determine the relationship of mortality to plasma osmolality and anion gap inpatients on haemodialysis.Methods: Fifty consecutive dialysis naive stable stage 5 chronic kidney disease subjects aged between 18 and 70 years, attending a Lagos Teaching Hospital were recruited. They were followed up from the salvage phase of 5 sessions carried out on alternate days through to the maintenance sessions of haemodialysis at a frequency of 2-3 times per week for six (6) months. Pre-and post-dialysis serum osmolality and anion gap were obtained for salvage and maintenance phases of haemodialysis.Results: Out of the 50 patients that started the study, 11 (22%) patients (9 males and 2 females) died while10 (20%) subjects (9 males and 1 female) were lost to follow-up before the commencement of the maintenance haemodialysis. Six more subjects (3 males and 3 females) withdrew from the study while 23(46%) entered the maintenance phase of the study. During the maintenance phase, 8(16%) (5 male and 3 female) subjects died while 15 subjects (30%) (9 males and 6 females) completed the study. The mean age of the subjects who completed the study was 46.2± 10.8years (46.9±9.4 years for the males and 45.4±12.1 years for the females).The mean age of the patients that died during maintenance haemodialysis was 46.6±10.9 years(46.1±12.0 years and 45.0±9.8 years for male and female respectively).The mean pre dialysis osmolality and anion gap during salvage haemodialysis were higher than the post dialysis values (298.15 ± 15 mOsm/kg vs. 276.0 ± 13.5 mOsm/kg, p=0.04 and 15.1 ± 3.3 vs. 13.6 ± 3.1, p=0.049).However, the mean pre and post dialysis osmolality and anion gap during maintenance haemodialysis sessions were similar [273.35±14.6mOsm/kg vs. 270.60±13.0 mOsm/kg (p=0.065)and 12.7±2.9 vs. 12.2±3.2(p=0.059)].There was no significant difference in the pre- and post- dialysis osmolality and  anion gap of those that died and those that survived to the end of the study (p>0.10).Conclusion: Changes in plasma osmolality and anion gapis not associated with increased mortality and hence may not be useful in predicting mortality during maintenance dialysis

The Development of Reference Values for the WHO Health Facility Core Prescribing Indicators

This study outlines a method for developing reference values for the WHO core prescribing indicators using survey-derived morbidity data and locally appropriate treatment guidelines developed by a panel of health care providers. Ten (10) health care facilities were selected randomly from two states in Nigeria (Edo and Delta). A retrospective cross-sectional survey of the prevalence and severity of clinical problems seen in these facilities was carried out using a minimum of 100 medical records per facility. A panel of health care providers reviewed relevant information on disease presentation for each encounter to confirm or impute a diagnosis.Another multidisciplinary expert panel reached consensus about the most appropriate local treatment for each diagnostic category thus identified, and assigned appropriate values to the core WHO prescribing indicator variables for the category. Reference values for the indicators were obtained by summing across all diagnostic categories the proportion of cases in the category times the consensus value assigned to the indicator variables for that category. One thousand one hundred and nine (1109) clinical encounters were evaluable. The predominant diseases were malaria (24.9%), acute respiratory infections (11.9%), skin disorders (7.0%), trauma (6.8%), non-specific fever (4.5%), diarrhoea (4.0%), miscellaneous disorders with a single diagnosis (23.0%), and encounters with multiple diagnoses (17.9%). Overall, 69.8% of cases were classified as mildly ill, 28.5% moderately and 1.7% of cases as severely ill. The local reference values derived for the WHO core prescribing indicators were as follows: average number of drugs per encounter (1.6-1.8); percentage encounters with injections (10.1%-17.0%); and with antibiotics (20.0%-25.4%). The maximum possible value of 100.0% was assigned to the percentages of drugs prescribed by generic name and those prescribed from the essential drug list. It is feasible to derive reference values for prescribing indicators by combining local clinical case mix data and consensus treatment guidelines for major disease entities. Key words: drug use; WHO; prescribing indicators; reference values; Nigeria Résumé Notre étude donne les grandes lignes d'une méthode servant à développer des valeurs de références pour les indicateurs de L'Organisation Mondiale pour la Santé (WHO) qui prescrivent les noyaux. On a utilisé des données de morbidité obtenues grâce à des enquêtes sur place et grâce à des conseils locaux établis par un groupe de dispensateurs de soins de santé. Nous avons choisi au hasard dix (10) services de santé dans deux Etats du Nigéria (Edo et Delta). Puis, s'agit d'une enqête rétrospective et englobante sur la prédominance et la sévérité des problèmes cliniques rencontrés dans ces services. Pour ce faire, on a pris un minimum de 100 dossiers médicaux par service. Un panel de dispensateurs de soins de santé a revu les renseignements pertinents sur la présentation de la maladie dans chaque incident afin de confirmer ou d'imputer des diagnoses. Un autre panel de spécialiates provenant de domaines différents est tombé d'accord à propos du traitement local le plus approprié pour chaque catégorie diagnostique ainsi identifiée. Ce panel a aussi attribué, pour la catégorie, des valeurs appropriées aux variables des indicateurs de l'Organisation Mondiale pour la Santé qui prescrivent les noyaux. Les valuers référentiielles ont été obtenues en déterminant, à travers toutes les catégories diagnostiques, la proportion des cas dans la catégorie et en la multipliant par la valeur du consensus assignée aux variables de l'indicateur pour cette catégorie. Mille cent-neuf incidents cliniques (1109) devaient être évalués. Les maladies prédominantes étaient: paludisme (24,9%), infections respiratoires aiguës (11,9%), désordres de la peau (7,5%), diarrhée (4,0%), désordres divers d'une diagnose (23,0%), incidents aux diagnoses multiples (17,9%). En tout, 69,8% des cas étaient classifiés comme un peu malade, 28,5% comme moyennement malade, et 1,7% comme gravement malade. Les valeurs référentielles locales retenues pour les indicateurs de l'Organisation Mondiale pour la Santé (WHO) prescrivant les noyaux sont les suivantes: nombre moyen de médicaments par incident (1,6-1,8); pourcentage des incidents exigeant des piqûres (10,1%) – 170%); incidents exigeant des antibiotiques (20,0%) – 25,4%). La valeur maximale de 100,0% pour les indicateurs de l'Organisation Mondiale pour la Santé (WHO) a été attribuée aux pourcentages des médicaments prescrits sous des noms génériques et à ceux prescrits à partir de la liste des médicaments essentiels. Il est possible d'obtenir les valeurs référentielles pour les indicateurs de prescription en combinant des données mixtes des cas clinques locaux et des conseils de traitement des entités de maladies majeures établis par un consensus. Mot cles: usage de medicaments; WHO; prescrivant indicateurs; valeurs référentielles; Nigéria West African Jnl of Pharmacology and Drug Research Vol.18 2002: 6-1