RESUMO
INTRODUCTION: since 2000s, epidemiological studies conducted by the Italian Ministry of Defence on Italian soldiers sent on a mission abroad showed excess mortality and/or incidence for Hodgkin lymphomas and also a significant reduction of all tumours and of all diseases. OBJECTIVES: this analysis aim to evaluate tumour incidence and overall mortality among Italian soldiers sent on a mission abroad (period 1996-2012; 3,663 cases). This investigation is preliminary to a more complete retrospective study on the cohort of soldiers affected by tumour (No. 6,104 cases) diagnosed in the period 1973-2017 and registered by the Epidemiological Defence Observatory (OED). MATERIALS AND METHODS: cohort data were acquired by the Uranium Commission of the Chamber of Deputies (CUC, 2016-2018). For statistical and epidemiological reasons, mainly dictated by the number, completeness, and quality of information concerning patients (or deceased) and the study population. The survey was temporarily limited to male military aged between 20 and 59 during the period 1996-2012 (No. 3,663; 60% of the total). Military from the four Italian defence forces - Air force, Carabinieri, Army, and Navy - were, respectively, divided into two groups: those involved in at least one mission abroad ("missionaries"; No. 874; 24%) and all the others ("non-missionaries"; No. 2,789; 76%). Using the method of indirect rate standardization, the age-standardized incidence ratio comparing missionaries and non-missionaries (SIRm) and comparing missionaries and the general population considered as an external reference (SIR) were calculated, with respective 90% confidence intervals (95%CI). Similarly, the overall mortality risk among missionaries was investigated. RESULTS: considering the population of the non-missionaries, the analysis of tumour incidence (TM) by military forces identified excesses in the missionaries of the Air Force (SIRm: 126.7; 90% CI 107.9-147.9), Carabinieri (SIRm: 152.8; 90%CI 134.0-173.7), and the Army (SIRm: 116.2; 90%CI 108.1-125.6). Taking into account missionaries, there was an excess of risk for specific neoplasia: for hemolymphopoietic system in Carabinieri (SIRm: 150.1; 90%CI 106.0 - 207.1) and in the Army (SIRm: 109.0; 90%CI 93.9-125.9); for Hodgkin lymphoma in Air force (SIRm: 187.7; 90%CI 88.1-352.5), Carabinieri (SIRm: 187.3; 90%CI 87.9-351.8), and the Army (SIRm; 104.5; 90%CI 81.2-132.6); for leukaemia in the Army (SIRm: 142.4; 90%CI 107.5-185.4). Significant risk excesses were also observed in missionaries for stomach, testis, kidney, bladder, and thyroid tumours. On the other hand, for missionaries in the Navy, a statistically significant risk reduction for all tumours emerged (SIRm: 61.1; IC90% 51.0-72.6). Missionaries showed a higher mortality for all causes. CONCLUSIONS: this preliminary study confirms the need for an in-depth survey on the health status of Italian soldiers. In particular, the risk for diseases, even non-neoplastic and after 2012, should be investigated in the military over the age of 60, who has a greater risk of incidence and mortality, not only for tumour. All potential disease determinants, both environmental and personal, should also be studied.