The duration and timing of exposure: Effects of socioeconomic environment on adult health

Objectives. This study investigated timing and duration effects of socio-economic status (SES) on self-rated health at 33 years of age and established whether health risks are modified by changing SES and whether cumulative SES operates through education. Methods. Data were from the 1958 British birth cohort. Occupational class at birth and at 16, 23, and 33 years of age was used to generate a lifetime SES score. Results. At 33 years of age, 12% of men and women reported poor health. SES at birth and at 16, 23, and 33 years of age was significantly associated with poor health: all ages except 16 years in men made an additional contribution to the prediction of poor health. No large differences in effect sizes emerged, suggesting that timing was not a major factor. Odds of poor health increased by 15% (men) and 18% (women) with a 1-unit increase in the lifetime SES score. Strong effects of lifetime SES persisted after adjustment for education level. Conclusions. SES from birth to 33 years of age had a cumulative effect on poor health in early adulthood. This highlights the importance of duration of exposure to socioeconomic conditions for adult health.