Follow-up and retrospective investigation of pneumoconiosis cases in a county of Ningbo City from 1974 to 2019
截至2019年底，宁海县用工单位接尘工人中累计诊断尘肺病例420例，完成随访409例（97.38%），失访11例（2.62%）。自1974年发现第1例尘肺病例起，宁海县在2000年以前、2000—2009年、2010—2019年各诊断尘肺病例39例、278例、101例。另有2 例尘肺病例诊断年份不详，1 例为死亡病例，1 例为失访病例。存活尘肺病例294例，主要分布于桑洲镇。诊断年龄为（58.68±15.37）岁，接尘工龄为8.0（4.0，15.7）年，叁期病例诊断年龄小于壹期和贰期，与贰期差异有统计学意义（
P<0.05）；年龄≥60岁者231例（78.57%），而≥80岁者74人（25.17%）；工龄<10年者160例（54.42%）；享受工伤保险补偿和用人单位民事赔偿者分别占12.59%与7.82%。从诊断年限看，2010—2019年组享受工伤保险补偿者、得到用人单位赔偿者占比较<2000年组、2000—2009年组高，差异均有统计学意义（ P<0.01）。死亡尘肺病例115例，尘肺壹期、贰期和叁期病死率分别为23.86%、18.18%和50.75%，叁期病死率高于壹期和贰期，差异均具有统计学意义（ P<0.05）；叁期病例的诊断年龄、死亡年龄均小于壹期和贰期，差异均具有统计学意义（ P<0.05）；65例尘肺病例死因明确，其中呼吸系统疾病（肺癌除外）25例（38.46%）、肿瘤28例（43.07%），在因肿瘤死亡的尘肺病例中，肺癌占50.00%。 结论
Pneumoconiosis is one of the most common and widespread prescribed occupational diseases in China, and there is no cure for it at present. The Healthy China 2030 underlines that the prevention and treatment of pneumoconiosis are the critical element of promoting occupational health.
To understand the basic characteristics, social security, and death causes of pneumoconiosis cases in Ninghai County, and to provide a basis for scientific prevention and treatment of pneumoconiosis.
Information on pneumoconiosis cases in Ninghai County from 1974 to 2019 was obtained by consulting occupational disease and occupational health information monitoring systems, occupational disease diagnosis institutions, and employers, which may retain original data on occupational pneumoconiosis diagnosis, as well as specialized epidemiological survey projects on pneumoconiosis. Telephone or face-to-face follow-up visits were conducted based on relevant information to complete or verify relevant information such as length of service with dust exposure, type, stage, and diagnosis date of pneumoconiosis. ANOVA, chi-square test, and rank-sum test were used to analyze age of diagnosis and age of death, entitlement to social security and mortality rate of cases/length of service.
As of the end of 2019, a total of 420 cases of pneumoconiosis were diagnosed among workers exposed to dust in Ninghai County, with 409 cases (97.38%) followed up and 11 cases (2.62%) lost to follow-up. Since the first case of pneumoconiosis was reported in 1974, 39 cases, 278 cases, and 101 cases of pneumoconiosis were reported before 2000, from 2000 to 2009, and from 2010 to 2019, respectively. Two other cases of pneumoconiosis were diagnosed with an unknown year, one as a dead case and one as a lost case. There were 294 surviving pneumoconiosis cases, who mainly lived in Sangzhou Town. The mean age of diagnosis was (58.68±15.37) years old, and the median length of service with exposure to dust was 8.0 (4.0, 15.7) years. The age of diagnosing stage III pneumoconiosis was less than that of stage I and stage II, and the difference between the age of diagnosing stage III and stage II pneumoconiosis was significant (
P<0.05). There were 231 cases (78.57%) aged ≥ 60 years, while there were 74 cases aged ≥ 80 years (25.17%). There were 160 cases (54.42%) whose length of service was < 10 years. There were 12.59% and 7.82% of the total cases compensated by work injury insurance and civil compensation by employers, respectively. From the perspective of diagnosis period, the proportion of patients who collected work-related injury insurance and civil compensation from employers in the 2010—2019 year group was higher than that in the <2000 year group or the 2000—2009 year group ( P<0.01). There were 115 fatal pneumoconiosis cases, and the fatality rates of stage I, II , and III pneumoconiosis were 23.86%, 18.18%, and 50.75%, respectively. The fatality rate of stage III pneumoconiosis was higher than that of stage I or II ( P<0.05). The age of diagnosis and age of death of stage III pneumoconiosis cases were lower than those of stage I and II ( P<0.05). The cause of death was definite in 65 patients, including 25 cases (38.46%) of respiratory diseases (except lung cancer) and 28 cases (43.07%) of tumors, and lung cancer accounted for 1/2 of the pneumoconiosis cases that died due to tumors. Conclusion
The surviving pneumoconiosis cases in Ninghai are mainly older than 60 years old and largely live in Sangzhou Town. Constructing local rehabilitation stations should be taken as an opportunity to actively prevent and treat pneumoconiosis complications, further improving the quality of life of pneumoconiosis patients.