高齢者のくも膜下出血治療の現状 ─医療費の観点から─

抄録

Introduction: The number of elderly patients with aneurysmal subarachnoid hemorrhage (SAH) is increasing with the aging of the population, placing a greater financial burden on the healthcare system. Aggressive treatment produces better outcomes than conservative care, but it is more expensive. The Japanese government has established a Diagnosis Procedure Combination (DPC) protocol that promotes a combination of surgical and conservative treatment for acute SAH patients, but there has been no research on the efficacy of this protocol with respect to patient age. The aim of this study was to compare patient outcomes and costs between patients under 50 years old and those 80 years and older.

Methods and Materials: We retrospectively collected the medical records of 259 consecutive SAH patients who received acute phase surgical treatment and preventive clinical care during the vasospasm period following SAH who had been admitted to our hospital between January 1^st, 2005 and June 30^th, 2017. Patients who received aggressive treatment were then divided into two age groups: those under 50 years of age (n=58) and those 80 years and older (n=21) for a total of 79 patients. The modified Rankin scale (mRS) was used to compare outcomes between the two age groups. Medical bills were used to compare the total cost of treatment between groups.

Results: Older patients tended to have poorer outcomes and higher medical costs than their younger counterparts. In the older age group, 10 cases (47.6%) were mRS 0-2 after treatment compared to 50 cases (86.2%) in the younger group. Older patients tended to enter care with a higher mRS and this may account for the results in our study. Patients 80 years and older spent 5,640,823 yen on average compared to 4.526.911 in the under 50 group. Unlike the prospective payment system of the USA, the Japanese DPC uses a point system that reimburses the hospital based on the procedure and length of stay in the hospital. Older patients tended to have longer length of stays and this contributed to the increased medical costs.

Discussion: Older patients had worse outcomes and spent more on treatment than younger patients. Advanced age does not preclude successful surgery for SAH, rather the initial clinical status is the strongest indicator of future outcomes. Further research is warranted to determine the cause of these differences in outcomes and to determine if aggressive treatment is ultimately the best treatment for patients over 80 years old.