BackgroundIntracerebral hemorrhage (ICH) is a disease with high mortality and a substantial risk of recurrence. However, the recurrence risk is poorly documented and the knowledge of potential predictors for recurrence among co-morbidities and medicine with antithrombotic effect is limited.Objectives1) To estimate the short- and long-term cumulative risks of recurrent intracerebral hemorrhage (ICH). 2) To investigate associations between typical comorbid diseases, surgical treatment, use of medicine with antithrombotic effects, including antithrombotic treatment (ATT), selective serotonin reuptake inhibitors (SSRI’s), and nonsteroidal anti-inflammatory drugs (NSAID’s) with recurrent ICH.MethodsThe cohort consisted of all individuals diagnosed with a primary ICH in Denmark 1996–2011. Information on comorbidities, surgical treatment for the primary ICH, and the use of ATT, SSRI’s and NSAID’s was retrieved from the Danish national health registers. The cumulative recurrence risk of ICH was estimated using the Aalen-Johansen estimator, thus taking into account the competing risk of death. Associations with potential predictors of recurrent ICH were estimated as rate ratios (RR’s) using Poisson regression. Propensity score matching was used for the analyses of medicine with antithrombotic effects.ResultsAmong 15,270 individuals diagnosed with a primary ICH, 2,053 recurrences were recorded, resulting in cumulative recurrence risk of 8.9% after one year and 13.7% after five years. Surgical treatment and renal insufficiency were associated with increased recurrence risks (RR 1.64, 95% CI 1.39–1.93 and RR 1.72, 95% CI 1.34–2.17, respectively), whereas anti-hypertensive treatment was associated with a reduced risk (RR 0.82, 95% CI 0.74–0.91). We observed non-significant associations between the use of any of the investigated medicines with antithrombotic effect (ATT, SSRI’s, NSAID’s) and recurrent ICH.ConclusionsThe substantial short-and long-term recurrence risks warrant aggressive management of hypertension following a primary ICH, particularly in patients treated surgically for the primary ICH, and patients with renal insufficiency.

ObjectivesTo estimate the risks of and identify predictors for recurrent subdural haematoma in surgically and conservatively treated patients.MethodsThe cohort comprised all individuals diagnosed with a first-time subdural hematoma in Denmark 1996–2011. Information on potential predictors was retrieved from the Danish health registers. Cumulative recurrence risks were estimated using the Aalen-Johansen estimator. Rate ratios (RR) were estimated using Poisson regression.ResultsAmong 10,158 individuals with a subdural hematoma, 1,555 had a recurrent event. The cumulative risk of recurrent subdural hematoma was 9% at 4 weeks after the primary bleeding, increasing to and stabilising at 14% after one year. Predictors associated with recurrence were: Male sex (RR 1.60, 95% CI:1.43–1.80), older age (>70 years compared to 20–49 years; RR 1.41, 95% CI: 1.21–1.65), alcohol addiction (RR 1.20, 95% CI:1.04–1.37), surgical treatment (RR 1.76, 95% CI:1.58–1.96), trauma diagnoses (RR 1.14, 95% CI:1.03–1.27), and diabetes mellitus (RR 1.40, 95% CI:1.11–1.74). Out of a selected combination of risk factors, the highest cumulative 1-year recurrence risks for subdural hematoma of 25% (compared to 14% for all patients) was found in surgically treated males with diabetes mellitus.ConclusionsThe recurrence risk of subdural hematoma is largely limited to the first year. Patient characteristics including co-morbidities greatly influence the recurrence risk of SDH, suggesting that individualized prognostic guidance and follow-up is needed.

PurposeLittle is known about the prognosis for school performance among children with all-cause infantile hydrocephalus (IHC). Using detailed educational data, we investigated the school performance for IHC patients compared to other children in Denmark.Patients and methodsWe conducted a population-based cohort study of all live-born children in Denmark (1977–2015) based on data from the Danish national health registers and the Danish educational register. The cumulative chance of completing school at age 18 years was estimated using the Aalen–Johansen estimator. The relative risks presented as ORs for not completing school, obtaining grades, or obtaining a grade point average below the national mean value were estimated using a logistic regression model.ResultsThe cohort included 2,381,413 children, and of these, 2,573 were diagnosed with IHC. A total of 86% of IHC children completed compulsory school compared to 96% among other children; only 62% of IHC children who completed school received marks vs 96% among other children. Mediation analyses indicated that one-third of these poorer performances in IHC children could be attributable to their higher prevalence of epilepsy, spasticity, visual disturbances, autism, and attention-deficit hyperactivity disorder. Completion rates were similar for isolated and non-isolated hydrocephalus, and did not vary by age at diagnosis or number of surgeries. Of the children with isolated IHC, 73% obtained grades vs 58% of the children with non-isolated IHC. Poorer school performance in IHC children was also observed when considering age at school start, grade point average, and completion of further education.ConclusionThe poorer school performance among IHC children is particularly reflected by the larger proportion not obtaining grades compared to other children. However, the performance of the IHC children obtaining grades is comparable to that of other children.