Long-term clinical outcomes of patients with primary chronic immune thrombocytopenia: a Danish population-based cohort study.

Few data exist on the long-term prognosis of patients with chronic primary chronic immune thrombocytopenia (ITP). We examined the risk of infections, hemorrhage resulting in hospitalization, hematologic malignancies, and total and cause-specific mortality among patients with ITP compared with the general population. We used population-based medical databases to identify 407 patients with primary chronic ITP diagnosed during 1996 to 2007 and 4069 general population members individually matched on age, sex, and comorbidity level. We used Cox regression analysis to estimate rate ratios (RRs) adjusted for age (≤ 60 or > 60 years), sex, calendar year, and level of comorbidity. The adjusted 1-year RR of infection was 4.5 (95% confidence interval [CI], 3.3-6.1) for patients with chronic ITP compared with the general population cohort. The adjusted RR decreased to 1.8 (95% CI, 1.3-2.5) for the second to fifth year of follow-up. The adjusted 5-year RR was 3.2 (95% CI, 1.2-9.0) for hospitalized intracranial hemorrhage, 4.4 (95% CI, 2.3-8.3) for other hospitalized hemorrhages, and 4.7 (95% CI, 1.7-12.7) for hematologic malignancy. The 5-year all-cause mortality RR was 2.3 (95% CI, 1.8-3.0). In summary, primary chronic ITP was associated with substantially increased long-term risk of infections, hemorrhagic episodes requiring hospitalization, hematologic malignancies, and mortality.

Monoclonal gammopathy of undetermined significance and risk of venous thromboembolism.

BACKGROUND: Patients with multiple myeloma are at increased risk of venous thromboembolism (VTE), but little information is available on VTE risk in patients with the precursor condition monoclonal gammopathy of undetermined significance (MGUS). OBJECTIVE: To evaluate the risk of VTE and its impact on mortality in patients with MGUS. PATIENTS AND METHODS: We identified 1610 patients with MGUS and no prior diagnosis of VTE during the 1978-2005 period in North Jutland County, Denmark. We used the Danish Central Population Registry to select 16,100 general population comparison cohort members with no prior VTE diagnosis, matched with the MGUS patients by age, sex, and comorbidity. Follow-up data on VTE incidence in the two groups were obtained from the Danish National Patient Registry covering all Danish hospitals. Time-varying Cox regression analysis was used to compute the incidence rate ratio (IRR) of VTE and the mortality rate ratio (MRR) for MGUS patients who developed VTE compared to MGUS patients without VTE. RESULTS: In the MGUS cohort, 50 VTE events were identified during 12,594 person-years (PY) of follow-up, corresponding to an incidence rate of 4.0 VTEs/1000 PY. The IRR for VTE among MGUS patients compared to the comparison cohort was 1.37 (95% confidence interval (CI): 1.00-1.88). Of the 50 MGUS patients with VTE, one was later diagnosed with malignant transformation. The adjusted MRR for MGUS patients with VTE compared to MGUS patients without VTE was 1.94 (95% CI: 1.36-2.77). CONCLUSIONS: MGUS is a risk factor for VTE, and VTE is a marker for increased mortality among MGUS patients.

Prevalence of hypospadias in Danish boys: a longitudinal study, 1977-2005.

BACKGROUND: Hypospadias is a relatively common congenital malformation. Data on temporal trends in prevalence of hypospadias are conflicting. It is unclear whether changes of maternal age distribution over time are associated with changes in hypospadias prevalence. OBJECTIVE: To study changes in prevalence of hypospadias in Denmark during a 29-yr period and to investigate whether maternal age was associated with the prevalence of hypospadias. DESIGN, SETTING, AND PARTICIPANTS: Through Denmark's National Patient Registry, covering all Danish hospitals, we identified all boys diagnosed with hypospadias in Denmark. From the Danish Medical Birth Registry, we obtained information on maternal age and on the annual total number of live-born boys from 1977 to 2005. MEASUREMENTS: Prevalence of hypospadias at birth. RESULTS AND LIMITATIONS: Among 921745 boys born alive from 1977 to 2005, we identified 3490 boys with hypospadias. The prevalence increased from 0.24% in 1977 to 0.52% in 2005, corresponding with an annual increase in prevalence of 2.40% (95% confidence interval: 1.94-2.86). The prevalence of hypospadias did not differ according to maternal age. The mean annual prevalence was 0.38% in sons of mothers aged 35 yr. CONCLUSIONS: The hypospadias prevalence was increasing in Denmark from 1977 to 2005. Increased maternal age did not explain this trend.