Utilization of CT and MRI scanning in Taiwan, 2000–2017

In this study, we assess the imaging growth rates that occurred from the year 2000 forward. While growth rates initially accelerated sharply, a significant drop-off occurred in 2004 and 2005. This is almost certainly a sequela of the severe acute respiratory syndrome (SARS) outbreak that hit Taiwan in 2003 and 2004 [16, 17]. Patients with non-emergent or less severe diseases likely felt anxious about visiting hospitals and clinics, resulting in a reduction in the use of medical imaging services [11]. The number of scans performed in 2005, the second year of the SARS outbreak, returned to pre-SARS levels only in terms of ED imaging (Additional file 1: Table S2). This likely reflects the increased need for emergent imaging related to the SARS outbreak.

The rates of CT and MRI usage were appreciably greater in the older population (54% of all scans performed in 2017), paralleling the growth of that population that has occurred in Taiwan (74.05% over the past 17 years). Specifically, the three most frequent categories of users of CT and MRI services were all older individuals who received the services as outpatients (Table 2). Likewise, outpatients accounted for a large proportion of the older population. Smith-Bindman reported similar growth rates for CT use in the older population (aged ≧ 65 years) in the United States, which reached 9.5% from 2000 to 2006, and was therefore similar to the growth rate seen in Ontario, Canada, from 2000 to 2007 [5]. After slowing between 2006 and 2013, the CT use growth rate in the older population in the US accelerated again, reaching 5.2%, from 2014 to 2016. Comparatively, MRI growth rates in the older population were 11.3% in the United States (2000–2005) and 22% in Ontario (2000–2007), slowing thereafter to 2.2% (2005–2016) and 4.9% (2010–2016), respectively [5]. In terms of other Asian countries, aside from South Korea, the Taiwanese elderly population has grown the fastest (109.12% versus 74.05%). The elderly populations in New Zealand, Australia, and Japan have also risen considerably (66.89%, 62.29%, and 56.75%, respectively). In addition, many other developed countries have seen growth rates in their elderly populations of between 25 and 50% over the past two decades (Additional file 1: Table S3) [18,19,20,21].

In 2017, approximately 61.5% of the CT scanners in Taiwan were 64 or greater-slice models, allowing for image quality and scanning speeds much greater than those derived from the original 4-slice scanners. In 2015, this figure was 50.40% [22]. Similarly, modern 3-T MRI systems are becoming more prevalent [23], accounting for 14.29% of all systems in 2015 and 15.93% in 2017 [24]. Therefore, in addition to physician and patient demand, easy access, and financial incentives (supportive policies by the Taiwanese government), technical improvements have also contributed to the rapid rise in CT and MRI usage.

Our results reveal that medical centers order almost equivalent numbers of CTs to those of regional hospitals and MRIs more than regional and local hospitals, suggesting that they should be if they are not already equipped with comparatively more advanced technologies. Given the generally greater frequency of complicated diseases that medical centers treat, a higher level of imaging quality is necessary [25].

Hospitals in the northern and southern metropolitan areas tended to have more equipment and resources, likely explaining their slightly increased utilization rates. However, the nearly similar rates seen in other areas are a testament to the egalitarianism of the health care system in Taiwan, despite the fact that metropolitan areas tend to have larger populations [25].

Despite a relatively low use of imaging (80.5 CTs and 29.4 MRIs per 1000 population in 2017) compared to other countries (Additional file 1: Table S4), Taiwan’s life expectancy has increased from 75.9 years in 2000 to 80.9 years in 2018, a rate comparable to those in other developed countries (Japan, 84.2 years; Korea, 82.7 years; and the United Kingdom, 81.3 years) and exceeding that in the United States (78.7 years) (Additional file 1: Table S5) [26]. However, global mortality due to malignant neoplasm is rapidly rising in the older population worldwide [27, 28], and Taiwan is not likely to be spared in the future. The diagnosis and treatment of malignancies requires extensive imaging and is likely to contribute to growth rates in imaging going forward.

Across Taiwan, there were 379 CT and 210 MRI scanners in 2015. This increased to 408 and 226, respectively, in 2017 [22, 24]. Worldwide, Japan had the most scanners per 1,000,000 inhabitants in 2017 (111.5 CT and 55.2 MRI scanners) followed by Australia (64.3 CT scanners) and the United States (39.2 MRI scanners). Taiwan lagged these countries considerably, with 16.9 CT scanners and 10.0 MRI scanners (Additional file 1: Table S6) [29, 30]. Therefore, Taiwan proves that high life expectancy can still exist despite a relatively low availability of CT and MRI scanners.

Enrollment in the NHI plan is mandatory for all citizens and foreign residents of Taiwan. NHI covers up to 99.8% of Taiwan’s 23.57 million inhabitants. It ensures that every resident has access to quality and affordable medical care, providing comprehensive coverage for emergency, inpatient, and outpatient care. In the United States, total estimated annual wasted spending on healthcare in 2019 has ranged from US $760 billion to US $935 billion. With total health care spending in 2019 projected at approximately US $3.82 trillion, it is believed that about 25% of these costs can be eliminated [31]. In Taiwan, wasted spending on healthcare amounted to more than US $55.55 million in 2017, driven in part by patients lost to follow-up after CT or MRI imaging, and ultimately leading some to repeat the tests at other hospitals [25]. According to data from 2004 and 2005, 21.5% of such patients returned within 90 days for a repeat scan. Repeat CTs and MRIs are performed most often on patients with malignancies (31.8%), neurologic disorders (24.0%), and brain or spinal injuries (25.3%) [39]. In 2019, the NHI restricted repeat scanning within 28 days without appropriate clinical indications [32].

Given the significant growth, medical imaging in Taiwan has taken up a larger and larger portion of the NHI budget in recent years [33]. Its annual expenditure totaled only US $ 8.9 billion in 2000 though reached US $19.9 billion in 2017 [34]. Some have questioned the cost-effectiveness of increased imaging, particularly in the emergency setting. Because most ED visits (48.0%) are made by older patients with multiple clinical problems, classifying those visits based on symptoms has proven difficult. However, Taiwan has observed a decline in admission rates following emergency CT, which was 59.9% in 2009 and only 48.2% in 2013 [35]. This suggests that there has been an increase in the number of unnecessary emergency scans performed. Thus, NHIA presented the patient referral system to lower down the outpatient volume at larger hospitals and set them to focus on providing the treatment for the illness. As a result, patient without referral requires to pay higher out-of-pocket fees. In addition, the cloud-based data sharing system introduced by NHIA have already reduced the amount of medical examinations performed (CT scans, in specific) and saved USD 38.86 million for 6 months of the second semester in 2017 [36].

Future imaging rates in Taiwan are likely to be driven by two opposing factors: population decline and aging. Declines in birth rates, and therefore overall population, is expected to drive imaging rates lower, particularly in the long run. However, aging is expected to increase imaging rates in the short term, given that older people tend to require more imaging [37]. Moreover, the diagnostic of patient with metastatic diseases has also rose up the usage of medical imaging, especially in the last month of their lives [38], which was in-line with the escalating cases of its incidence rate [39]. The cumulative effect on the number of imaging studies performed is difficult to predict, but imaging per capita is likely to increase.

The major strength of this study is that the data includes all CTs and MRIs performed within the NHI system in Taiwan, which essentially includes the entire population. In addition, because the number of scans performed was taken from a single-payer billing database (in contrast to self-reported survey data or data obtained from the literature), the data is likely to be highly accurate.

Limitations

Some patients had more than one anatomical area scanned during a single visit were recorded as having received only a single scan. In addition, self-payment imaging was not included. These likely resulted in a slight underestimate of the total number of scans performed. Furthermore, this study only analyzed the numbers of uses, not adjusting to the individuals. Also, detailed information on the diseases of which imaging was performed could not be included, so the classification of diseases was challenging. This highlights the need for further large-scale studies for the justifications of imaging conducted and evaluation of imaging usage in the particular diseases.

留言 (0)

沒有登入
gif