Starvation and Future Cardiovascular Disease

Summary of published paper¹

The Leningrad siege occurred during the Second World War, as German troops prevented supplies reaching the city from 8th of Sep 1941 to January 27th 1944. If rations were received in full, which was not always the case, the population received about 460 calories per day (mostly bread, oil and sugar) with virtually no protein. Out of a population of 2.9 million, 630,000 died from hunger related causes, most during the winter of 1941-2. Arecent study examined whether the siege increased risk of mortality, particularly from cardiovascular disease in subsequent years.

As part of the 1973 US-Soviet collaborative programme, data were collected for a lipid research programme. This involved a baseline survey undertaken in Leningrad between 1975-7 in which 5000 men, born between 1916-35, were randomly selected in Petrogradsky district. Data were collected on socio-economic factors, anthropometric measures and biological measurements, e.g. blood pressure, cholesterol concentration and cardiovascular dysfunction. Nearly a third of those surveyed had lived in Leningrad during the siege, which meant that they likely spent the whole siege period there since most people were unable to leave.

Analysis of the data showed a significant excess risk of high systolic and diastolic blood pressure in men who lived through the siege. Those who were around the age of puberty (9-15 years) at the peak of starvation (January 1942) were especially prone to high systolic blood pressure (odds ratio 1.56, 95% confidence interval 1.21 to 2.02), with a mean excess of 3.3 mm Hg. Except for a tendency to have a greater skinfold thickness, all other indicators of cardiovascular risk were remarkably similar for those exposed and non-exposed to the siege.

During the follow up, 2048 out of the remaining sample of 3905 men died. Cardiovascular disease accounted for 1050 deaths (51%), 662 from ischaemic heart disease and 333 from stroke, 97 of which were haemorrhagic. The excess risk of dying for those who experienced the siege was 21% (relative risk 1.21, 1.20-1.32). The excess risk of dying from ischaemic heart disease was 28% (1.28, 1.08-1.51). Among those aged 9-15 years at the peak of starvation, this estimate was 1.39 (1.07-1.79). The effects of starvation around puberty were stronger still for stroke (167, 1.15- 2.43), including haemorrhagic stroke (1.71, 0.9- 3.22). For stroke, but not for other mortality, the siege effect was significantly stronger for those who experienced it around puberty than at other ages.

Lifestyle and socio-economic circumstances did not confound the association between cardiovascular mortality and siege exposure. It appears that critical stages in the process of regulating blood pressure may occur during puberty and that starvation may cause permanent disruption of blood pressure regulation. Other potential mediating factors (for example endocrine changes) were not measured, and thus these conclusions remain hypothetical. The nutritional component of starvation is also entangled with the trauma of the siege.

The study does, however, indicate that puberty may be a highly vulnerable period and that starvation in puberty today may have implications for future cardiovascular disease in many developing countries.

¹Sparen, P et al (2004). Long term mortality after severe starvation during the siege of Leningrad: prospective cohort study. BMJ volume 328, 3rd January 2004, pp 11-14