Correspondence

Genetics of Stroke

N Engl J Med 2003; 348:1407April 3, 2003

Article

To the Editor:

We concur with Dr. Tournier-Lasserve (Nov. 21 issue)1 that linkage methods for genetic studies of stroke are hampered by difficulties in collecting pedigrees with several affected members.2 There are ongoing studies that should allow this goal to be accomplished. The National Institute of Neurological Disorders and Stroke is supporting a 50-center study in North America known as the Siblings with Ischemic Stroke Study.3 Though not designed to assemble extended, multiplex families as was done in Iceland, this study will assemble 300 sibling pairs and trios for the purpose of performing a genome-wide scan for loci that confer an increased risk of ischemic stroke. Informative pedigrees in the Siblings with Ischemic Stroke Study are identified with the use of a centralized system of proband-initiated contact.4 As of November 2002, 86 pedigrees had been assembled. This program should allow an independent assessment of whether a gene at the 5q12 locus is associated with an increased risk of ischemic stroke in the heterogeneous North American population.

James F. Meschia, M.D.
Thomas G. Brott, M.D.
Robert D. Brown, Jr., M.D.
Mayo Clinic, Jacksonville, FL 32224

for the Siblings with Ischemic Stroke Study Investigators

4 References

1. 1

   Tournier-Lasserve E. New players in the genetics of stroke. N Engl J Med 2002;347:1711-1712
   Full Text | Web of Science | Medline

2. 2

   Meschia JF, Brown RD Jr, Brott TG, Hardy J, Atkinson EJ, O'Brien PC. Feasibility of an affected sibling pair study in ischemic stroke: results of a 2-center family history registry. Stroke 2001;32:2939-2941
   CrossRef | Web of Science | Medline

3. 3

   Meschia JF, Brown RD Jr, Brott TG, Chukwudelunzu FE, Hardy J, Rich SS. The Siblings With Ischemic Stroke Study (SWISS) protocol. BMC Med Genet 2002;3:1-1
   CrossRef | Medline

4. 4

   Worrall BB, Chen DT, Meschia JF. Ethical and methodological issues in pedigree stroke research. Stroke 2001;32:1242-1249
   CrossRef | Web of Science | Medline

To the Editor:

In the opening sentence of her article, Tournier-Lasserve states, “Stroke is the second leading cause of death and the most common cause of disability in the world.” This statement is misleading according to the World Health Report 2002.1

In the mortality report, specific diseases or conditions are grouped under subheadings classified under three categories: communicable diseases, maternal and perinatal conditions, and nutritional deficiencies (32.5 percent of 56.554 million deaths in 2001); noncommunicable conditions (58.5 percent); and injuries (9 percent). If we consider groups of diseases under the subheadings, the leading cause of death in the world is cardiovascular disease (29.3 percent), followed by infectious and parasitic diseases (19.3 percent) and malignant neoplasms (12.6 percent). Stroke is thus the fourth leading cause of death in the world. In developed countries, stroke is considered the third most common cause of death, after coronary heart disease and cancer.

Joseph K.T. Ngeh, M.R.C.P.
Vivien K.L. Toh, M.R.C.P.
Radcliffe Infirmary, Oxford OX2 6HE, United Kingdom
jngeh@aol.com

1 References

1. 1

   The world health report 2002: reducing risks, promoting healthy life. Geneva: World Health Organization, 2002. (Also available at http://www.who.int/whr/2002/en/.)