Leslie Simpson

Leslie O. Simpson is a retired hemorheologist from New Zealand who has researched the red blood cells of patients with myalgic encephalomyelitis (ME). According to Simpson's research in the 1980s and 1990s the red cells of ME patients show shape deformities that cause impaired microcirculation of the blood in the capillaries.

Non-deformable erythrocytes
Simpson became interested in ME as some of the disease symptoms were suggestive of impaired microcirculation. In 1986 he reported impaired filtration of red blood cells in a sample of ME-patients. His pioneering paper suggested ME to be “associated with changes in blood rheology which could impair microcirculatory blood flow.” This study sparked the interest of T.M. Mukherjee and colleagues in Australia. In a letter published in The Lancet, they reported red cell deformities in some ME patients that they had never seen before. The report by Mukherjee was however criticized for not using a proper control group. Lloyd et al. tried to replicate the findings in 12 patients with CFS and 10 healthy controls, but found that most of the cells from patients and controls had normal, smooth biconcave morphology.

Interest in blood cell deformity and impaired circulation in ME patients waned with only Simpson publishing about the topic. In a 1989 study he compared a large sample of patients with (self-reported) ME with MS patients and healthy controls. Samples from subjects with myalgic encephalomyelitis had the lowest percentages of normal shaped red cells and the highest incidence of cup forms. Through collaboration with ME organizations in New Zealand, Australia, South Africa and England, Simpson  managed to test more than 2000 ME-patients. Once again he found red cell shape transformation. “The results reported here, he wrote, “would support a proposal that ME is a hemorrheological disorder in which symptoms are manifestations of the consequences of impaired capillary blood flow.” But because the study was uncontrolled the British Journal of Haematology refused to publish it.

Ramsay's disease
In 2013 Simpson published a book with ME-patients and psychotherapist Nancy Blake. it's was called "Ramsay’s disease. Myalgic Encephalomyelitis (ME) and the Unfortunate Creation of 'CFS'." In the book Simpson explains his theory of red blood cell deformability and capillary restriction in ME. He thinks this biological mechanism could account for the characteristic relapsing course Melvin Ramsay noted in patients with ME. According to Simpson “It would be very difficult to imagine a disease process caused by a persistent viral infection or a persisting immunological aberration, which allowed a return to normality for hour, days or weeks.”

Although Simpson thinks erythrocyte deformability is a key element of ME he does not see it as something unique to this disease. He wrote that “the changes in red cell shape populations which occur in ME also occur in other chronic disorders so red cell shape analysis alone is not diagnostic for ME. The observed changes are probably of importance in the pathogenesis of tiredness.” Simpson had previously reported about red blood cell changes in multiple sclerosis and other diseases. Simpson does thinks red cell deformity is an important pathological mechanism in ME and he recommended research into treatment, to focus on the issue of blood circulation. Simpson suggested that evening primrose oil could improve the flow properties of blood.

OMF-research
In 2018 the Open Medicine foundation announced it would fund research into erythrocyte deformability in patients with ME/CFS. A preliminary study demonstrated a significant decrease in deformability of red blood cells in patients with ME/CFS, suggesting this could be used as a biomarker for the disease.