Marit Rønning

Prescription drug use among fathers and mothers before and during pregnancy. A population‐based cohort study of 106 000 pregnancies in Norway 2004–2006

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Mothers are using medicines during pregnancies; the extent varies across the world and is generally difficult to compare. In this registry-based study, we examined more than 100,000 Norwegian pregnancies and described the drug prescription pattern of both fathers and mothers around conception and during pregnancy (mothers). WHAT THIS STUDY ADDS In every trimester of pregnancy, about 30% of the mothers was dispensed a drug. The total drug exposure did not seem to diminish throughout pregnancy. One-quarter of the fathers was dispensed drugs during the last 3 months prior to conception. AIMS The primary aim of this study was to describe the use of prescribed drugs in both mothers and fathers before and during pregnancy in Norway. METHODS This population-based cohort study was based on data retrieved from the Medical Birth Registry of Norway and the Norwegian Prescription Database. These registries cover the entire population of Norway. Information on >100,000 births during 2004-2006 in the birth registry was linked to prescription data. Prescriptions issued to mothers just prior to, during and after the pregnancies as well as prescriptions to fathers just prior to conception were identified. RESULTS Among mothers, 83% were prescribed drugs during the period 3 months prior to estimated conception until 3 months after giving birth. The mothers who received drugs were prescribed on average 3.3 different Anatomical Therapeutic Chemical (ATC) codes (range 1-38). During pregnancy, 57% were prescribed drugs. In the first trimester, 33% of mothers were dispensed drugs, while the figure was 29% for mothers in the last trimester. Among fathers, 25% used prescribed drugs during the 3 months prior to conception, with on average 1.9 different ATC codes (range 1-22). CONCLUSION Large proportions of both fathers and mothers were dispensed drugs prior to conception or during pregnancy. While there is a high awareness of the issues involved in maternal drug use in pregnancy, possible teratogenic effects of drug use in fathers shortly before conception should be further explored.

Different versions of the anatomical therapeutic chemical classification system and the defined daily dose : are drug utilisation data comparable?

Abstract. Objective: To investigate whether published drug utilisation studies contain satisfactory references to the ATC/DDD version applied and thus are usable for comparative purposes. Methods and results: A literature survey of drug utilisation studies was made. Seventy-three articles were identified by two Medline searches, one in 1996 and another in 1998. The articles were classified into four different groups. Groups 1 and 2 give proper references to the defined daily doses (DDDs) used in the studies, either by full reference to the version of the ATC Index with DDDs or by listing the actual DDDs used. The articles in groups 1 and 2 represent 46% of the articles in the survey. The articles classified in groups 3 and 4 give references only to general articles about the anatomical therapeutic chemical classification (ATC)/DDD system or no references at all. Fifty-four percent of the articles in the survey were classified in these groups. In these articles it is not possible to identify which DDDs have been used in the presentation of drug consumption data. Conclusions: According to the results from our literature survey, it is not common practice to include the ATC codes and the DDD values used or to make reference to the versions of the ATC/DDD index used when results from drug utilisation studies are published. One possible reason for this might be little or no knowledge about the ATC/DDD system as a dynamic system in which alterations are made annually. The lack of references to the actual DDDs used in the studies make comparisons between different data sets difficult and misleading.

THE USAGE OF VETERINARY ANTIBACTERIAL DRUGS FOR MASTITIS IN CATTLE IN NORWAY AND SWEDEN DURING 1990-1997

The prescribing patterns and annual incidence of use of antibacterial drugs for the treatment of mastitis in cattle in Norway and Sweden during the period 1990-1997 were estimated from drug wholesaler statistics. Although the drugs included in this study are also used in other species and/or other indications, mastitis in cattle is by far the most-common indication for their use. We used these sales figures to evaluate trends in the use of antibacterial drugs and changes in the incidence of treatment in bovine mastitis in Norway and Sweden. To facilitate comparisons (correcting for differences in activity and dosage) between the relative proportions of antibacterial drugs used in bovine mastitis, we introduced defined daily dose cow (DDDcow) as unit of measurement. Tentative DDDcow for the various injectable drugs were derived from doses recommended in Norway and Sweden. For intramammary drugs administered in the form of single-dose applicators, one applicator was defined as the DDDcow. The prescribing patterns of antibacterial drugs in bovine mastitis in Norway and Sweden during the study period seemed to be influenced by treatment policies, substances and formulations approved and treatment cost; length of the withdrawal period also seemed to play a role.

Problems in collecting comparable national drug use data in Europe: the example of antibacterials

ObjectiveTo describe the methodological problems in collecting retrospectively comparable data on drug use and to compare the use of antibacterials in some European countries.MethodsA spreadsheet was distributed in 2000 through the European Drug Utilisation Research Group (EuroDURG) network, requesting 1994–1999 data on use of antibacterials for systemic use (ATC group J01), from ambulatory, hospital, or total care, aggregated at ATC 4th level, and presented in defined daily doses per 1000 inhabitants per day (in the 1999 ATC/DDD version or specified other version).ResultsThe network was able to provide national utilization data for two or more years in the requested period from 16 countries (4 only from primary care, 3 both from primary care and total use, and 9 only total use data). The main methodological problems identified were: use of divergent ATC/DDD versions, divergent assignment of DDDs for combination products and the use of unofficial or national DDDs. It was possible to correct for the different ATC/DDD versions to some extent, except for the cephalosporin group (not included in the analysis), as the collection of data at the ATC 4th level precluded recalculation of DDDs. In the seven countries with primary care data the total J01 antibacterials use varied by a factor of 2.5 (Belgium 23.4 and The Netherlands 9.5 DDDs per 1000inhabitants per day). The use of J01A tetracyclines varied fourfold, and the use of J01C penicillins and J01F macrolides and lincosamides approximately threefold. Significant reduction over time was seen in J01A and an increase in J01F.ConclusionsIn the scientific and regulatory community it is still difficult to perform a valid and comprehensive cross-national collection of utilization data on antibacterials. White spots on the European map persist for ambulatory care data, and data are missing for the hospital sector in most countries. For a thorough explanation of the considerable intercountry variability (especially in antibacterial subgroups and time trends analysis) a sustained and concerted effort is necessary to implement a validation process of the ATC/DDD use in the various countries and to adopt a common methodological approach to the collection of utilization data at the substance level (ATC 5th level).

Prevalence, incidence and persistence of etanercept and adalimumab in Norway 2005–2009

Examining the prevalence, incidence and persistence of use of etanercept and adalimumab in Norway during 2005–2009.

Recommendations for national registers of medicinal products with validated ATC codes and DDD values

Medicines have important effect on population health and it is important to have a system for assessing their effects and monitoring their use, expenditure and price. The basis for all these objectives is the availability of an internationally valid classification system of medicines and a measurement system of their utilisation. Since 1996 the WHO Headquarter has adopted and proposed the ATC (Anatomical Therapeutical Chemical) classiifcation and the DDD (Defined Daily Dose) as the global standard for medicine classification and utilisation sudies, respectively. The EURO-MED-STAT project has defined the criteria for the production, validation and maintenance of national registers with validated ATC codes and DDD values, as suggested by WHO. A register with a valid ATC code and DDD value is able to provide reliable information allowing calculation of utilisation and expenditure indicators (Utilisation in DDD; DDD/1000inh/day and Expenditure per DDD).