Sickle cell disease is very variable in its outlook. In rural parts of Africa children rarely survive beyond the first year. On the other hand in developed Western countries many patients with sickle cell anaemia survive well into adult life. The commonest cause of death is infection.
Previously stated mortality was (1):
In the USA the median life expectancy in HbSS is:
In the USA the median life expectancy in HbSC is:
Factors which modify the condition are elevated levels of fetal haemoglobin and the co-existence of thalassaemia. For example, in India and parts of Eastern Saudi Arabia patients are often asymptomatic with sickle cell anaemia because they produce very high levels of foetal haemoglobin.
Most deaths from this condition occur in the second six months of life.
Notes:
- mortality and morbidity rates in sickle cell disease (SCD) have been considerably reduced since the introduction of hydroxyurea (HU) in the 1990s (2)
- an update of the Multicenter Study of Hydroxyurea (MSH) showed that at 9 years' follow-up, the mortality rate among patients who take HU is reduced 40% compared with the rate among patients who do not take the drug
- a study was undertaken to evaluate the pattern of medical care utilization and mortality in children and adults with sickle cell disease (SCD) in the state of Tennessee (3)
- rates of hospitalization, emergency department visits, and deaths were measured in a cohort of adults and children with SCD enrolled in TennCare, Tennessee's Medicaid managed health care program, from January 1995 to December 2002
- for children less than 5 years of age, the mortality rate was similar to that of other black Tennessee children (P = 0.71). Among children, the death rate was highest in 10-19 years of age and was 8-fold higher than Tennessee's race- and age-specific rate
- among 20- to 49-year-old patients with SCD, mortality was significantly higher in males than in females (P < 0.001)
- as compared to the black population without SCD in TennCare, patients with SCD had 7-30 times higher rate of hospitalization and 2-6 times higher rates of emergency department visits (P < 0.001
- death rates among children 10-19 years old with SCD are higher than those among children<5 years of age
Reference:
- 1) Platt OS, Brambilla DJ, Rosse WF, et al. (June 1994). "Mortality in sickle cell disease. Life expectancy and risk factors for early death". N. Engl. J. Med. 330 (23): 1639-44
- 2) Steinberg MH, Barton F, Castro O, et al. Effect of hydroxyurea on mortality and morbidity in adult sickle cell anemia: risks and benefits up to 9 years of treatment. JAMA. 2003;289: 1645-1651.
- 3) Shankar SM, Arbogast PG, Mitchel E, Cooper WO, Wang WC, Griffin MR.Medical care utilization and mortality in sickle cell disease: a population-based study Am J Hematol. 2005 Dec;80(4):262-70