Unnatural-cause mortality patterns of Northern Finnish men and women diverge in adolescence – A 52-year follow-up

The Finnish population has a long life expectancy but ranks high in unnatural deaths on the European scale. Mortality has historical regional discrepancy in Finland, as Northern Finns are overrepresented in both natural and unnatural deaths. This study aimed to characterize the age- and sex-related trends in unnatural mortality among Northern Finns. Altogether 12 143 individuals, constituting >95% of births in Northern Finland in 1966, were followed up for a median of 52 years. The mortality patterns of this population were studied using death record data. Crude annual mortality rates were calculated and graphed for 10-year age strata (all-cause, natural-cause, and unnatural-cause mortality, as well as accident, suicide, and homicide mortality). Cox regression was used to analyze the sex discrepancy in mortality. A total of 874 deaths (7.2%) occurred during the follow-up period. Women had 47% and 73% lower risks of any death and unnatural death than men, respectively. From the second decade of life onwards, the unnatural mortality of men was 3–5 times that of women. Accident and suicide mortality rates of men were 2–13 and 2–3 times those of women, respectively. Homicides were rare among either sex. We conclude that Northern Finnish women have a substantially lower risk of all-cause mortality and unnatural mortality than men. To aid the development of preventive strategies, future studies should aim to identify the underlying factors behind unnatural mortality. Primarily, emphasis should be placed on the increased mortality of men from the second decade of life onwards.