Background 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.
Objective 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.
Methods 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.
Results 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.