Wang Q. et al., 2023: Trends of Urolithiasis in China: A National Study Based on Hospitalized Patients from 2013 to 2018
Wang Q, Wang Y, Yang C, Wang J, Shi Y, Wang H, Zhang L, Zhao MH.
Renal Division, Department of Medicine, Peking University First Hospital, Institute of Nephrology, Peking University, Beijing, China.
Department of Nephrology, Xiangya Hospital Central South University, Changsha, China.
Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases, Chinese Academy of Medical Sciences, Beijing, China.
Advanced Institute of Information Technology, Peking University, Hangzhou, China.
China Standard Medical Information Research Center, Shenzhen, China.
Clinical Trial Unit, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.
National Institute of Health Data Science at Peking University, Beijing, China.
Peking-Tsinghua Center for Life Sciences, Beijing, China.
Introduction: The aim of this study was to explore the chronological trends in clinical features and utilization of healthcare resources for hospitalized patients with urolithiasis in China.
Methods: Patients with urolithiasis were extracted from the Hospital Quality Monitoring System, a national database of hospitalized patients in China, based on the International Classification of Diseases, Tenth Revision, codes. Variables including demographic characteristics, comorbidities, treatment modalities for urolithiasis, length of hospital stay, and expenditures were collected and analyzed.
Results: Among 79.8 million hospitalized patients, 3.5 million were diagnosed with urolithiasis with an increasing trend (from 3.0% in 2013 to 4.0% in 2018). Most of these patients had upper urinary tract calculi (76.6% in 2013 and 81.7% in 2018). Middle-aged patients (46-65 years) constituted the largest proportion with a stable trend (from 46.9% in 2013 to 48.8% in 2018), while the proportion of older patients (>65 years) showed an increasing trend (from 23.7% in 2013 to 27.4% in 2018). The percentages of gout/hyperuricemia, hypertension, diabetes, and cardiovascular disease among the hospitalized patients with urolithiasis increased steadily, with the sharpest increases in patients from rural areas. Overall, 656,952 patients (18.9%) received surgical interventions for urolithiasis. The proportions of ureteroscopy and extracorporeal shockwave lithotripsy increased steadily during the 6-year study period, with simultaneous decreases in open surgery and percutaneous nephrolithotomy. The median length of hospital stay decreased from 10 days to 8 days. The cost of urolithiasis intervention accounted for 2.0% of the total hospitalization fee in 2013 and increased to 2.7% in 2018.
Conclusions: The analysis showed an increasing trend in the percentage of hospitalized patients with urolithiasis, accompanied by an increased percentage of the total hospitalization fee for urolithiasis intervention during the 6-year study period. Based on the increasing trends in the proportion of older patients (>65 years) and percentages of metabolic comorbidities among patients with urolithiasis, an increased burden of urolithiasis on the healthcare system in China is anticipated.
Kidney Dis (Basel). 2022 Nov 7;9(1):49-57. doi: 10.1159/000527967. eCollection 2023 Jan. PMID: 36756086. FREE ARTICLE
Impressive data on the epidemiology of urolithiasis. Based on the large numbers alone, it will be included in many papers and textbooks on stone diseases.
However, there are some details weakening the conclusions. The data shed light on fundamental problems in the evaluation and interpretation of database-supported records.
The massive changes in absolute numbers cannot be due to changes in incidence, but to changes in data collection. If similar changes take place in the recording of total hospital admissions, calculations of the relative incidence of urolithiasis in hospital admissions appear equally doubtful. The data come from the Hospital Quality Surveillance System introduced by the Chinese government in January 2013, and may reflect the problems associated with establishing such a system. It is well known that coding is an essential part of hospital economics. E.g., if many concomitant diseases are coded for a patient, the reimbursement may increase, as treatment of a “difficult” patient is more expensive/rewarding.
This circumstance becomes visible only in the discussion: “only approximately 20% of hospitalized patients with urolithiasis were admitted for interventions per se, while the others were admitted for treatment of other diseases and had urolithiasis as a comorbidity.”
SWL increased from 6.1% in 2013 to 10.7% in 2018 and surpassed open surgery in 2016. This despite the fact that only data from tertiary hospitals are included.