Trends in venous thromboembolism-related hospitalizations, 1994-2009

Abstract

Objective: Information on trends in venous thromboembolism (VTE) in US children is scant and inconsistent. We assessed national trends in VTE-associated pediatric hospitalizations.

Methods: All nonroutine newborn hospitalizations for children 0 to 17 years of age in the 1994-2009 Nationwide Inpatient Samples were included; routine newborn discharges were excluded. VTE diagnoses were identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification codes. Variance weighted least square regression was used to assess trends in patient characteristics and rates of hospitalization per 100000 population <18 years of age. Multivariable logistic regression models were used to estimate the probability of VTE diagnosis over the study period.

Results: The rate of VTE-associated hospitalization increased for all age subgroups (<1, 1-5, 6-11, and 12-17 years), with the largest increase noted among children <1 year of age (from 18.1 per 100000 during 1994 to 49.6 per 100000 during 2009). Compared with 1994-1997, the adjusted odds of hospitalization with a VTE diagnosis were 88% higher during 2006-2009 (adjusted odds ratio: 1.88 [95% confidence interval: 1.64-2.17]). Venous catheter use, mechanical ventilation, malignancy, hospitalization ≥ 5 days, and VTE-related medical conditions were associated with increased likelihood of VTE diagnosis.

Conclusions: The rate of VTE-associated hospitalization among US children increased from 1994 through 2009. Increases in venous catheter procedures were associated with and may have contributed to the observed trends. The degree to which increased awareness of VTE influenced the temporal differences could not be determined.

FIGURE 1

Age-specific rates of VTE-associated hospitalization among US children <1 year, 1–5 years, 6–11 years, and 12–17 years, 1994–2009 NIS. P value for trend <.001 for all age strata.

FIGURE 2

Comparison of age-standardized rates of VTE-associated hospitalizations among US children <18 years of age, 2000, 2003, and 2006 NIS and KID. Standardized to 2000 US Census population <18 years of age; error bars represent SE of estimates. P value for 3-year trend was .02 for NIS and <.001 for KID. No significant difference (P ≥.05) between rates of hospitalization for NIS and KID during 2000, 2003, and 2006.