Poster Number-24 - An epidemiological study of fibromyalgia based on real-world data in a northern city in China

An epidemiological study of fibromyalgia based on real-world data in a northern city in China

Purpose: Fibromyalgia (FM) is a common chronic diffuse pain syndrome in which, in addition to multi-site pain, patients often suffer from a variety of clinical symptoms such as fatigue, sleep and mood disorders [1], and thus FM often causes a heavy socioeconomic burden. The current global prevalence of FM is about 2-4% [2]. The prevalence of FM is gradually increasing due to factors such as an aging population, increased psychological stress, and an increase in poor lifestyle habits. However, there is a general lack of awareness among clinicians in mainland China regarding this serious disease [3]. On one hand, FM guidelines have only been promulgated and updated in China since 2011, which is a relatively short period of time for promotion; on the other hand, because of the diverse clinical manifestations of FM and the lack of specific diagnostic indicators, diagnosis is difficult and most physicians lack relevant clinical experience. In line with this understanding, epidemiologically, there is a lack of systematic studies on the prevalence and trends of FM in mainland China. To promote the understanding and awareness of FM among clinicians in mainland China, this study systematically identifies patients diagnosed with FM in the region through a regional database of electronic medical records, and demonstrates the prevalence and epidemiological trends of FM through changes in the number of patients diagnosed with FM over a 10-year period from 2010 to 2020.

Methods: Tianjin is a second-tier city in the north, one of the four major municipalities in China. Tianjin Regional Health Care Big Data Platform is currently one of the best platforms in terms of data quality governance within mainland China. The platform covers a population of about 16 million and contains a majority of tertiary and secondary hospitals in the region (a total of 80 hospitals in Tianjin, including 43 tertiary hospitals and 37 secondary hospitals). This study used the electronic medical record (EMR) and health information system (HIS) data in the platform to include patients with at least one diagnosis containing ICD-10 code M79.7 (fibromyalgia) or with an exact match of the diagnosis name "fibromyalgia" or "fibromyalgia syndrome"(“纤维肌痛”或“纤维肌痛综合症”或“纤维肌痛综合征” in Chinese) from October 1, 2010 to September 30, 2020 after the promulgation of the FM diagnostic criteria. Each patient's socio-demographic and diagnostic information were extracted, and the unstructured text was standardized and normalized using natural language processing techniques. The final analysis data set was formed and statistically analyzed.

Results: From October 1, 2010 to September 30, 2020, in 80 hospitals in Tianjin, the total number of confirmed FM diagnosis was 981. Among them, 289 (29.5%) were male and 692 (70.5%) were female, with a male to female ratio of approximately 1:2.4. The average age of FM patients at first diagnosis was 53.34±12.80 years, and 78.54% had urban medical insurance.

Based on a resident population of 13,866,009 in Tianjin in 2020, the proportion of people who were diagnosed with FM in Tianjin was 7.1/100,000, which was much lower than the prevalence rate of similar populations (0.82% in Hong Kong, China [4]). The reason for this is probably related to the low rate of both consultation and diagnosis of FM in China, in addition to the geographical area. According to a survey, 24.1% of respondents in China had never been seen for chronic pain [5]. A study in a hospital in Hebei, a northern province in China, showed that the rate of misdiagnosis at the first visit was as high as 87% [6], and physicians lacked awareness to recognize FM [3].

The number of new FM patients has shown a gradual increase over the past decade. The number of new FM patients per year increased from 7 in 2011, to 40 in 2015, to 233 in 2020. With the promulgation of the first Chinese guidelines in 2011 [7], and the popularity of the FM disease concept and ICD10 diagnostic criteria began among clinicians, the number of new FM patients slowly increased each year. Wolfe [8] et al. and The Analgesic, Anesthetic, and Addiction Clinical Trial Translations Innovations Opportunities and Networks (ACTTION) public-private partnership with the U.S. Food and Drug Administration (FDA) and the American Pain Society (APS) [9] simplified and clarified the definitions of FM and chronic pain in 2016 and 2019, respectively, causing the number of confirmed diagnoses to show a significant upward in the respective years.

Conclusion: With the popularization and optimization of diagnostic criteria, the number of confirmed FM patients in Tianjin is gradually increasing, but the proportion of confirmed FM patients in the overall population is much lower than the prevalence rates in Europe, the United States, Hong Kong and Taiwan, suggesting that the diagnosis rate of FM patients in China is low. Therefore, it is necessary to improve clinicians' awareness of fibromyalgia as well as to popularize and standardize the related diagnostic measures.

References: References.
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