Objective To assess the incidence of cancer among male airline pilots in the Nordic countries, with special reference to risk related to cosmic radiation. Design Retrospective cohort study, with follow up of cancer incidence through the national cancer registries. Setting Denmark, Finland, Iceland, Norway, and Sweden. Participants 10 032 male airline pilots, with an average follow up of 17 years. Main outcome measures Standardised incidence ratios, with expected numbers based on national cancer incidence rates; dose-response analysis using Poisson regression. Results 466 cases of cancer were diagnosed compared with 456 expected. The only significantly increased standardised incidence ratios were for skin cancer: melanoma 2.3 (95% confidence interval 1.7 to 3.0), non-melanoma 2.1 (1.7 to 2.8), basal cell carcinoma 2.5 (1.9 to 3.2). The relative risk of skin cancers increased with the estimated radiation dose. The relative risk of prostate cancer increased with increasing number of flight hours in long distance aircraft. Conclusions This study does not indicate a marked increase in cancer risk attributable to cosmic radiation, although some influence of cosmic radiation on skin cancer cannot be entirely excluded. The suggestion of an association between number of long distance flights (possibly related to circadian hormonal disturbances) and prostate cancer needs to be confirmed.

Cosmic radiation is an occupational risk factor for commercial aircrews. In this large European cohort study (ESCAPE) its association with cancer mortality was investigated on the basis of individual effective dose estimates for 19,184 male pilots. Mean annual doses were in the range of 2-5 mSv and cumulative lifetime doses did not exceed 80 mSv. All-cause and all-cancer mortality was low for all exposure categories. A significant negative risk trend for all-cause mortality was seen with increasing dose. Neither external and internal comparisons nor nested case-control analyses showed any substantially increased risks for cancer mortality due to ionizing radiation. However, the number of deaths for specific types of cancer was low and the confidence intervals of the risk estimates were rather wide. Difficulties in interpreting mortality risk estimates for time-dependent exposures are discussed.

An autopsy was performed in 460 consecutive cases of sudden death among 35- to 76-year-old men. The closest cohabiting individual known to each decreased subject was interviewed. Snoring history was obtained in 321 of the 371 interviews. In 86 cases there was a history of 'habitual' (almost always or always) snoring, and 88 men snored 'often'. The mean age of subjects was 55.4 years. The mean body mass index (BMI) was 26.3 kg m-2. Among the obese snorers (n = 82), apnoeas had been observed 'occasionally', 'often', or 'habitually' in 49 cases. Death was classified as cardiovascular in 186 (40.4%) cases. Cardiovascular cause of death was more common among those who snored habitually or often than among those who snored occasionally or never (P less than 0.05). 'Habitual' snorers died more often while sleeping (P less than 0.05). Habitual snoring was found to be a risk factor for morning death (P less than 0.01). The possibility of obstructive sleep apnoea as a cause of sudden death should at least be considered if the decreased is known to have been a habitual snorer.

We conducted a retrospective cohort study to investigate whether work as a cabin attendant is related to an increased risk for spontaneous abortion. Data on female cabin crew members were linked to medical records on pregnancies. There were 1751 eligible pregnancies for the final analysis. Flight attendants who worked during early pregnancy had a slightly elevated risk of spontaneous abortion, as compared with attendants who were pregnant outside a time span of active flying (odds ratio [OR] = 1.3; 95% confidence interval [CI], 0.9 to 1.8). During the earliest years of the study period (1973 through 1977), the risk seemed to be decreased (OR = 0.4; 95% CI, 0.2 to 1.1), whereas during the later years (1978 through 1994) the risk was increased (OR = 1.6; 95% CI, 1.1 to 2.4). The results are in agreement with earlier studies, showing suggestive evidence of a slightly increased risk of spontaneous abortion among female cabin crew members.