Assess the prevalence and risk factors of abnormal neurological findings in sickle cell disease (SCD) patients with NO known symptomatic neurological insults.

Patients with SCD are prone to symptomatic neurological complications. Previous studies reported accrual of neural injury starting at early age, even without having symptomatic neurological events.   

Our study extracted patients diagnosed with SCD from the Cooperative Study of Sickle Cell Disease (CSSCD), which was conducted from 1977 to 1995 on 4000 patients. Patients from CSSCD who underwent a neurological evaluation were included in our analysis. Patients with previous neurological insults were excluded. We compared SCD patients with abnormal neurological findings with those without in terms of clinical and laboratory parameters.

A total of 3573 SCD patients were included. 519 (14.5%) patients had at least one abnormal neurological finding. The most common findings in descending order were abnormal reflexes, ataxia, cerebellar dysfunction, nystagmus, abnormal muscle tone and strength, Romberg sign, Horner's syndrome, language deficits, and intellectual impairment.

Patients with abnormal findings were significantly more likely to be males; older; smokers; obese; had higher systolic blood pressure; and more frequent history of pain crisis, aseptic necrosis, eye disease, osteomyelitis, hand foot syndrome, renal insufficiency, lung infarction, abnormal cholecystograms, blood transfusions, and surgical operations. Their labs revealed significantly higher reticulocytes but lower hemoglobin F, lactate dehydrogenase and albumin levels.

Using binary logistic regression, history of eye disease (OR=2.82, 95%CI=1.66-4.79, p<0.001), osteomyelitis (OR=2.54, 95%CI=1.34-4.83, p=0.004), aseptic necrosis (OR=1.56, 95%CI=1.04-2.34,  p=0.03), smoking (OR=1.54, 95%CI=1.03-2.29, p=0.033), male gender (OR=1.53, 95%CI=1.07-2.20, p=0.019) and hand foot syndrome (OR=1.47, 95%CI=1.01-2.13, p=0.039) were risk factors for abnormal neurological findings.

Neurological deficits are relatively common in patients with SCD, even without documented neurological insults. They range from peripheral and ophthalmic deficits to central and cognitive disabilities. Patients with SCD should have regular neurological evaluations and risk factors modification.