The authors, from Johns Hopkins, evaluated graduates of The Johns Hopkins University School of Medicine in an effort to study the relationship between socioeconomic status (SES) in childhood and cardiac outcomes in adulthood. It included 1337 members from the graduating classes of 1948–1964, excluding women (121), those of non European ancestry (36), and those who did not answer the questions about parental occupation (56) or were unavailable for follow-up (15), leaving 1131 white male medical students for analysis.
During medical school, all subjects had a medical history and physical examination. Questionnaires were mailed annually to collect follow-up data. Childhood SES was defined by the subjects’ father’s occupation and categorized into low, middle, and high SES groups. Information on cardiac risk factors was gathered on each subject, including serum cholesterol, physical activity, family history of premature coronary heart disease (CHD), body mass index (BMI), hypertension, cigarette smoking, coffee consumption, diabetes mellitus, and clinical depression.
Annual survey return rates generally exceeded 70% in each of the study years, and 85% of subjects answered at least once in each 5-year period. After a mean of 40 years of follow-up (representing 43,160 patient-years), the incidence of CHD before age 50 was more prevalent in the 216 subjects from the low SES group compared to the 915 subjects in the high SES group (6.2% vs 0.3%, P=.01). This difference remained statistically significant even after adjusting for the CHD covariate risk factors described above. The mean age for developing hypertension, diabetes, and smoking did not differ between the 2 groups, and the risk of developing CHD after age 50 did not differ significantly. However, subjects from the low SES group had a statistically significant higher average BMI at ages 40–49, 50–59, and 60–69 years.
The authors speculate on 3 possible models to explain their findings. First, the latent effects model posits that deleterious events early in life permanently alter the risk of developing disease. Second, the pathway model proposes that early events act on adult health by setting in motion a pattern of behavior that adversely affects health outcome. Finally, the cumulative model states that health outcomes are most determined by the cumulative length of time one is exposed to adverse environmental factors.
Dr. Robbins has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of a commercial product/device. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.
Pediatricians have always believed they could affect a child’s life with guidance and counseling during a patient’s youth. By studying a select group of white physicians, these authors attempt to determine whether a factor out of our control, SES during childhood, has a more powerful effect on a child’s future risk of heart disease than risk factors over which we have more control (diet,...