RESUMO
BACKGROUND: The greatest disease burden of sickle cell disease occurs early in life. Understanding factors that reduce disease related events in this period is therefore important. Hence, we assessed the impact of early care at a specialist center on the incidence of acute events during the first five years. METHODS: This was a retrospective cohort study among Jamaican children with sickle cell disease. Medical records of patients born January, 2004 to December, 2009, who were registered at the Sickle Cell Unit, a specialist care facility, were abstracted for dates of initiation to care, first occurrence and frequency of the outcomes of interest (vaso-occlusive crises, acute splenic sequestration, acute chest syndrome, and infection). Patients were classified according to whether initiation of care was before (early) or after 5 months of age (late). Using standardized t-tests, χ2 tests, and a multiple-failure survival analysis the rates of acute events between groups were compared. RESULTS: Of the total study group (n= 290), homozygous sickle cell disease accounted for 97% and 95% of the early (n=113) and late groups (n=177) respectively. The mean age of presentation in the early and late group was 0.2 and 2.3 years (p<0.01), with a mean length of follow-up of 5.2 and 3.2 years respectively (p<0.01). Vaso-occlusive crisis (n=880) and acute chest syndrome (n= 571) together accounted for 91.6% of the total number of events (n=1584). The risk of vaso-occlusive crisis and acute chest syndrome (among patients who presented with these acute events) was significantly higher in the "late" group, by 43% (Incidence rate ratio, (IRR) = 1.43, p<0.001); 95% CI (1.18-1.72) and 40% (IRR=1.40. p=0.002), 95% CI (1.12-1.75) respectively compared to "early" group. There was no difference in risk between groups for acute splenic sequestration and infection among persons presenting with these events. CONCLUSION: The risk of acute events in children with sickle cell disease exposed to early care at a specialist care is significantly less. Therefore, widespread screening with rapid referral to a specialist center stands to reduce substantial morbidity in Jamaica and other regions with high prevalence of sickle cell disease.
Assuntos
Síndrome Torácica Aguda , Anemia Falciforme , Síndrome Torácica Aguda/epidemiologia , Síndrome Torácica Aguda/etiologia , Anemia Falciforme/complicações , Anemia Falciforme/epidemiologia , Criança , Pré-Escolar , Homozigoto , Humanos , Lactente , Estudos Retrospectivos , EspecializaçãoRESUMO
This study investigated the association of nutritional and haematological variables with maximum time-averaged mean velocity (TAMV) measured by transcranial Doppler (TCD) velocity and the agreement of classification between two protocols. TCD categories included: normal (<170 cm/s), conditional (170-199 cm/s) and abnormal (≥200 cm/s) based on TAMV in distal internal carotid artery (dICA), middle cerebral artery (MCA), internal carotid bifurcation, anterior and posterior cerebral arteries. Of 358 children with sickle cell anaemia (SCA) examined, the mean age (±standard deviation) was 7·4 ± 2·7 years; 13·1% and 6·7% had conditional and abnormal velocities, respectively. Children with abnormal TCD velocities had higher prevalence of prior stroke (P = 0·006). Increased TAMV was associated with younger age (P = 0·001), lower weight (P = 0·001), height (P = 0·007) and oxygen saturation (P = 0·005). There was no association of TAMV with height-age or body mass index (BMI) z-scores. Adjusting for gender, BMI z-score, age, previous stroke and oxygen saturation, mean corpuscular volume (P = 0·005) and reticulocyte count (P = 0·013) were positively associated with TAMV, while haemoglobin concentration (P = 0·009) was negatively associated. There was good agreement [99%; weighted Kappa 0·98 (95% confidence interval 0·89-1), P = 0·0001] in TCD classification using data from five vessels versus two vessels (dICA and MCA). Haematological variables, rather than nutritional status, may be useful markers that identify high-risk children with SCA.