Prenatal exposure to the Great Chinese Famine and mid-age hypertension

Abstract

Background: One of the most terrible famines last century was Great Chinese Famine (GCF) in 1959~1961 when millions of people died from starving. Under-nutrition during famine between the Western and Eastern (Dutch Hungry vs. GCF) was similar, while cardiovascular consequences might not be the same. Addressing such questions may gain new insight into prevention of cardiovascular diseases.

Methods: A retrospective cohort of 18,593 participants aged 43-49 years of old, was from Suzhou, China. Logistic regression model was used to calculate the relative risk (RR) of hypertension and corresponding 95% confidence interval (CI). The multivariate RRs were adjusted for age, plasma glucose, triglyceride, and cholesterol.

Results: The multivariate RRs of systolic and diastolic pressure were not significantly elevated in the rural subgroups, but was higher in the urban population born in the famine (systolic pressure adjust RR 1.382, 95% CI 1.235-1.545, diastolic pressure adjust RR 1.569, 95% CI 1.415-1.740). The risks of hypertension were significantly higher among the urban subjects than that in the rural subgroups (systolic hypertension adjust RR 2.915, 95% CI 2.616-3.249, diastolic hypertension adjust RR 4.568, 95% CI 4.079-5.116). Percentile of optimal diastolic pressure at mid-age was significantly lower in the urban population prenatally exposed to the famine regardless of sexes. However, a similar reduction of percentage of optimal systolic pressure was only seen in the female, not the male population in the urban region.

Conclusion: The data suggest Asian genetic basis was not able to block famine-programmed vascular diseases as that happened in Europe, and the programmed problems due to under-nutrition could be reversed after birth. Protective mechanisms may be related to diet habits before age of 30 years old, which is important contribution to early prevention of hypertension.

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Fig 1. The natural population growth rate in Suzhou area during the time period 1957–1963.

Fig 2. Hypertension prevalence at 43~49-year-old in the male and female following exposure to GCF.

(A), (C): Male. (B), (D): Female. Non-exposed: un-exposed to the famine; Exposed: prenatally exposed to the famine. SP: systolic pressure; DP: diastolic pressure. (C), (D) The proportion of optimal blood pressure. The optimal blood pressure was determined as ≤120mmHg and ≤80mmHg, and the hypertension were determined as SP≥140mmHg and/or DP≥90mmHg. Total male: n = 9,924; n(urban) = 5,486 [n(exposed) = 2,662, and n(non-exposed) = 2,824]; n(rural) = 4,438 [n(exposed) = 2,212, and n(non-exposed) = 2,226]. Total female: n = 8,669; n(urban) = 4,370 [n(exposed) = 2,182, and n(non-exposed) = 2,188]; n(rural) = 4,299 [n(exposed) = 2,056, and n(non-exposed) = 2,243]. *, p< 0.01(exposed vs. non-exposed); #, p< 0.01 (urban vs. rural).

Fig 3. The annual per-capita disposable income and food consumption in Suzhou during the period of 1981–1985.

(A) The annual per-capita disposable income and Engel's Coefficient in Suzhou during the period of 1981–1985. (B) The food consumption in Suzhou area in 1981.