Despite ongoing debates about its safety, the use of metamizole (dipyrone) is still increasing in many countries. In this study, we analysed spontaneous reports of suspected metamizole‐associated agranulocytosis recorded in EudraVigilance database from 1985 to 2017 with regard to patient and treatment characteristics as well as fatal vs non‐fatal outcomes and compared these findings among countries. A total of 1448 reports from 31 different countries were included (Germany 42.0%; Spain 29.6%; Switzerland 13.1%; other countries 15.3%). Mean age of patients was 53.6 years (63.4% females). Differences among countries were observed, for example with respect to patient age, route of administration and daily doses. Overall, median time between starting metamizole and developing an agranulocytosis was 13 days with 34.7% of cases occurring up to 7 days. This time was much shorter in patients who had already received metamizole before (median: 6 vs 15 days). About 16% of cases ended fatally. Patients with fatal outcomes were older and more often had also received methotrexate compared to those with non‐fatal outcomes. When adjusting for age and sex in a multivariable logistic regression, methotrexate was associated with an increased risk of fatal outcomes (odds ratio: 5.18; 95% confidence interval: 3.06‐8.78). In conclusion, metamizole‐associated agranulocytosis is still a life‐threatening condition, especially in the elderly and those also receiving methotrexate. As agranulocytosis can develop weeks after last administration and independently of dose and duration of treatment, prescribers and patients should be aware of its signs and symptoms.
14 August 2017 in BMC Medical Research Methodology
This cohort study examined the impact of the lengths of lookback and confirmation periods as well as the definition of confirmatory events on the number of incident cancer cases identified and age-standardized cumulative incidences (ACI) estimated in administrative data using German cancer registry data as a benchmark. ACI per 100,000 insured persons for breast, prostate and colorectal cancer were estimated using BARMER Statutory Health Insurance claims data. Incident cancer cases were defined as having an in- or outpatient diagnosis in 2013, no diagnosis in a lookback period of 1 year and a second diagnosis (or death) in a confirmation period of 1 quarter. We varied lookback periods from 1 to 7 years, confirmation periods from 1 to 4 quarters as well as the definition of confirmatory events and compared ACI estimates to cancer registry data. ACI were higher for breast (138.7) and prostate (103.6) but lower for colorectal cancer (42.1) when compared to cancer registries (119.3, 98.0 and 45.5, respectively). Extending the lookback period to 7 years reduced ACI to 129.0, 95.1 and 38.3. An extended confirmation period of 4 quarters increased ACI to 151.3, 114.9 and 46.8. Including breast and colorectal surgeries as a confirmatory event reduced ACI to 114.9 and 37.1, respectively. The choice of lookback and confirmation periods and the definition of confirmatory events have considerable impact on the number of incident cancer cases identified and ACI estimated. Researchers need to be aware of potential misclassification when identifying incident cancer cases in administrative data. Further validation studies as well as studies using administrative data to estimate cancer incidences should consider several choices of the lookback and confirmation periods and the definition of confirmatory events to show how these parameters impact the validity and robustness of their results.
26 March 2017 in Pharmacoepidemiology and Drug Safety
Background: Urinary tract infections are among the most common reason for encounter and subsequent antibiotic prescriptions. Due to the risk of collateral damage and increasing resistance rates, explicit recommendations against the use of fluoroquinolones like ciprofloxacin in uncomplicated urinary tract infections have been issued. However, to what extent these recommendations were followed and if there are relevant differences between the disciplines involved (general practitioners, urologists, paediatricians and gynaecologists) are unknown.Methods: We used anonymized data from a local statutory health insurance (SHI) company, which covered about 38% of all SHI-insured persons in the federal state of Bremen, Germany between 2015—2019. Data included demographics, outpatient diagnoses and filled prescriptions on an individual level.Results: One-year prevalence of urinary tract infections was 5.8% in 2015 (females: 9.2%, males: 2.5%). Of all 102,715 UTI cases, 78.6% referred to females and 21.4% to males, 6.0% of cases were younger than 18 years. In females, general practitioners were the most common diagnosing speciality (52.2%), followed by urologists (20.0%) and gynaecologists (16.1%). Overall, fluoroquinolones were most often prescribed (26.3%), followed by fosfomycin (16.1%) and the combination of sulfamethoxazole and trimethoprim (14.2%). Fluoroquinolones were most often prescribed by urologists and general practitioners, while gynaecologists preferred fosfomycin. During the study period, shares of fluoroquinolones decreased from 29.4% to 8.7% in females and from 45.9% to 22.3% in males.Conclusions: Despite a clear trend toward a more guideline adherent prescription pattern, there is still room for improvement regarding the use of second-line antibiotics especially fluoroquinolones. The choice of antibiotics prescribed differs between specialities with higher uptake of guideline-recommended antibiotics by gynaecologists, mainly because of higher prescription shares of fosfomycin.
The non-opioid analgesic metamizole (dipyrone) is commonly used in Germany despite its narrow indications and market withdrawal from several countries. In this study we analyzed prescribing patterns of metamizole focusing on regional differences. The source of data was the “Information system for health care data” which includes data from the statutory health insurance funds for about 70 million Germans. We received aggregated data of individuals with at least one metamizole prescription in 2010 as well as the number of prescribed packages by age, sex, state and district along with the number of insured persons in each stratum. We calculated prescription prevalence stratified by age, sex, state and district. Among 68.4 million insured persons (mean age: 43.6 years; 53.0% female) 5.5 million received at least one metamizole prescription (8.1%, overall 12.2 million packages). Prevalence increased with age, and women received metamizole more often than men. In adults (total prevalence: 9.4%), levels varied between 7.0% (Saxony) and 11.1% (Schleswig-Holstein), whereas on a district level use ranged from 4.3% to 14.3%. In 2010, one of 12 individuals received metamizole at least once. Noticeable were the large regional variations which certainly cannot be explained by patient-related factors.