Comorbidity Adjustment in Health Insurance Claim Database / 보건행정학회지

The value of using health insurance claim database is continuously rising in healthcare research. In studies where comorbidities act as a confounder, comorbidity adjustment holds importance. Yet researchers are faced with a myriad of options without sufficient information on how to appropriately adjust comorbidity. The purpose of this study is to assist in selecting an appropriate index, look back period and data range for comorbidity adjustment. No consensus has been formed regarding the appropriate index, look back period and data range in comorbidity adjustment. This study recommends the Charlson comorbidity index be selected when predicting the outcome such as mortality, and the Elixhauser's comorbidity measures be selected when analyzing the relations between various comorbidities and outcomes. A longer look back period and inclusion of all diagnoses of both inpatient and outpatient data led to increased prevalence of comorbidities, but contributed little to model performance. Limited data range, such as the inclusion of primary diagnoses only, may complement limitations of the health insurance claim database, but could miss important comorbidities. This study suggests that all diagnoses of both inpatients and outpatients data, excluding rule-out diagnosis, be observed for at least 1 year look back period prior to the index date. The comorbidity index, look back period, and data range must be considered for comorbidity adjustment. To provide better guidance to researchers, follow-up studies should be conducted using the three factors based on specific diseases and surgeries.

Blood Management System in Japan / 대한수혈학회지

Information on the blood safety management system in Japan was collected by visiting the Ministry of Health, Labour and Welfare (MHLW), Japanese Red Cross Blood Service Headquarter, Kanto-Koshinetsu Block Blood Center, and Yurakucho Blood Room of Tokyo Metropolitan Blood Center, in July 2014, to improve the quality of the blood management system in Korea. In Japan, all blood products are supplied by the Japanese Red Cross Blood Service. In April 2012, the function of screening tests and blood product production of the provincial blood centers was transferred to the block blood centers. Donor suitability is assessed by medical doctors and EKG was tested for donors over 40 years old annually. To prevent bacterial contamination, the shelf life of platelets was shortened to 4 days after production, but routine bacterial screening test was not performed. Adverse reactions and infection following transfusions are reported to MHLW through the Red Cross Blood Service, and the case was reviewed by Pharmaceuticals and Medical Devices Agency (PMDA). Before transfusion, HBsAg, anti-HBs, anti-HBc, anti-HCV, and HCVcAg of the recipient is tested, and testing for HIV antigen is performed if the recipient has risk factors for HIV infection. Even when hepatitis B NAT is positive, look back is not performed if anti-HBc is negative and there is no history of blood donation within 125 days before the current donation. Good Manufacturing Practice (GMP) for blood centers was introduced in the 1990s and PMDA performs the test every 5 years. In introduction of GMP in Korea, it is necessary to decide how to absorb the expense.

HTLV-1/2 transfusional e hemovigilância: a contribuição dos estudos de look-back / Transfusion-transmitted HTLV-1/2 and hemovigilance: the contribution of look-back studies

Os vírus linfotrópicos de células T humana tipo 1 (HTLV-1) e tipo 2 (HTLV-2) foram os primeiros retrovírus identificados em humanos, em 1980 e 1982, respectivamente. O HTLV-1 é associado à leucemia/linfoma de células T do adulto (ATL) e mielopatia associada ao HTLV-1/ paraparesia espástica tropical (HAM/TSP). Tais vírus podem ser transmitidos por via vertical (mãe para criança) principalmente pela amamentação; por via sexual e via parenteral (usuários de drogas e transfusão de sangue e componentes). Nas áreas endêmicas, as transmissões vertical e sexual têm sido as principais vias para a disseminação da infecção por HTLV-1. Porém, a hemotransfusão parece ter importante participação na introdução do HTLV em populações não endêmicas. A via mais eficaz de transmissão transfusional do HTLV-1 é através de componentes celulares do sangue contaminado. No passado, isso ocorria principalmente através da transfusão de sangue não testado para o HTLV-1/2. Eficiência de transmissão transfusional da ordem de 60 por cento foi descrita nos primeiros trabalhos japoneses. Subseqüentemente, extremos de 13 por cento a 80 por cento foram descritos nos estudos retrospectivos realizados nos Estados Unidos. Tamanha variação na eficiência da transmissão transfusional foi influenciada pelos parâmetros: tipo do produto sangüíneo, tempo decorrido entre a coleta dos componentes celulares até seu uso transfusional e carga proviral do HTLV no doador. Estima-se que 4 por cento a 8 por cento dos receptores de unidades celulares infectados por HTLV-1 possam desenvolver HAM/TSP, sendo raros os casos descritos de ATL nestes receptores. "Look-back"é o termo usado em hemovigilância para um programa que notifica grupos de receptores de hemotransfusão, de seus riscos quanto à exposição a um agente infeccioso por ocasião de transfusão prévia. "Look-back targeted"é o programa para identificar receptores de unidades previamente doadas por doadores específicos e que subseqüentemente...

In 1980 and 1982, respectively human T-Lymphotropic virus type 1 (HTLV-1) and type 2 (HTLV-2) were the first retroviruses identified in human beings. HTLV-1 is associated with adult T cell leukemia/lymphoma (ATL) and HTLV-associated myelopathy/Tropical Spastic Paraparesis (HAM/TSP). These viruses can be transmitted vertically (from mother to child), mainly by breast feeding; by sexual relationships and parenteral drug delivery (intravenous drug users and transfusion of blood and blood components). In endemic areas, vertical and sexual transmission has been the principal manner of dissemination of HTLV-1 infection. However, blood transfusion seems to have an important role in introducing HTLV in non-endemic populations. The most efficient way of transmission of HTLV-1 is through cell components of contaminated blood. In the past, this occurred chiefly through blood transfusions not tested for HTLV-1. An efficiency of transfusion transmission of 60 percent was described in the first reports of Japanese research. Thereafter, extremes of 13 percent to 80 percent were described in retrospectives studies performed in the USA. Such variations in the efficiency of transmission by transfusions were influenced by parameters such as: blood product type, time spent from collection of the cell components until its transfusion and proviral load of the donor. It is estimated that about 4 to 8 percent of receptors of HTLV infected cell units can develop HAM/TSP, with ATL being rare in these receptors. Look-back is the term used in hemovigilance for a program that notifies blood transfusion receptors of the risks involved in exposure to infectious agents due to a preceding transfusion. "Targeted look-back"is the program used to identify receptors of blood units donated by specific individuals that subsequently have been identified as infected by a specific agent (for example HTLV). This involves identification of previous blood component units transfused...