Potential of a large historical occupational cohort to assess the health impacts of life-course events in Ireland: a pilot study

Abstract

BackgroundHealth care in historical contexts can provide important information on potential buffering from ecological shocks experienced by people through their life-course. We aimed to assess the potential utility of an historical medical archive of a large-scale manufacturer to examine impacts of major events on the lives of a cohort of Dublin men between 1912 and 1922. MethodsWe transcribed anthropometric data of men from hand-written pre-employment registries (1889–1957) for an 11-year period 1912–22 which included events such as the General Strike [1913], Irish Rising [1916], World War 1 [1914–18], and Spanish Influenza pandemic [1918]. Welch's ANOVA assessed changes in anthropometric measurements during each year of the 11 years: age, chest measurements, body-mass index (BMI) and number of applicants. Chest measurements and BMI were adjusted for age. FindingsWe used data from 4547 men (mean age 23·32 years [SD 7·48]). BMI differed significantly over the 11-year period (F(10, 4176)=79·587, p<0·0001). On average, applicants in 1917 had the lowest BMI (mean 19·24 kg/m2 [SD 2·17]), and applicants in 1913 had the highest BMI (22·37 kg/m2 [2·15]). Apart from 1914 (mean 21·90 kg/m2 [SD 2·15], p=0·780), average BMI in 1913 was significantly higher (p<0·0001) than for any other year (1912, 21·72 kg/m2 [2·16]; 1915, 19·68 kg/m2 [SD 2·16]; 1916, 19·66 kg/m2 [2·16]; 1917, 19·24 kg/m2 [2·17]; 1918, 19·36 kg/m2 [2·17]; 1919, 21·59 kg/m2 [2·16]; 1920, 21·33 kg/m2 [2·15]; 1921, 19·73 kg/m2 [2·16]; 1922, 20·26 kg/m2 [2·16]). Chest expansion differed over the 11-year period (F(10, 4071)=66·828, p< 0·0001). On average, applicants during 1916, 1917, and 1918 had below-normal chest expansion (<6·35 cm): mean 5·13 cm (SD 2·00), 4·92 cm (1·99), and 4·98 cm (2·00), respectively. InterpretationThe pilot dataset shows a clear period effect coinciding with major historical events, particularly World War 1, and provides unique insight into the physical condition of these men. This pilot confirms the feasibility of working further with this rare source of health data and the potential to explore health impacts of life-course events. Further investigation will compare younger cohorts who experienced relative peace-time conditions and examine early adulthood anthropometric measurements with subsequent chronic disease. FundingUniversity College Dublin Seed Funding (career development award).