Antiphospholipid Antibodies and the Risk of Stroke in Urban and Rural Tanzania: A Community-Based Case-Control Study.
The burden of stroke is high in sub-Saharan Africa, and improved knowledge of risk factors is needed. Antiphospholipid antibodies are a common acquired stroke risk factor in young individuals. Antiphospholipid antibodies may be induced by infectious diseases. Sub-Saharan Africa has a high infectious burden, and we analyzed the contribution of antiphospholipid antibodies to the risk of stroke in an incident population from rural and urban Tanzania.



Stroke cases and age- and sex-matched community-acquired controls from the rural Hai district and urban Dar-es-Salaam areas of Tanzania were recruited in a wider study of stroke incidence between June 2003 and June 2006. Lupus anticoagulant, anticardiolipin, anti-β2-glycoprotein I, and antiphosphatidylserine/prothrombin antibodies were determined in stored plasma, as well as IgG antibodies against Treponema pallidum.



Data from 158 stroke cases and 369 controls were analyzed. Thirty cases (19%) and 4 controls (1%) had a lupus anticoagulant (odds ratio, 20.8; 95% confidence interval, 7.2-60.5). Anticardiolipin IgG was the only other antiphospholipid antibody subtype associated with increased stroke risk (odds ratio, 2.1; 95% confidence interval, 1.0-4.3), but this association disappeared when corrected for IgG antibodies against Treponema pallidum results. The prevalence of anti-β2-glycoprotein I IgG antibodies in the Tanzanian healthy population was high when Dutch cutoff values were applied (67%), whereas presence of anti-β2-glycoprotein I IgM was associated with a reduced stroke risk (odds ratio 0.3; 95% confidence interval, 0.1-1.1).



The presence of lupus anticoagulant is a strong, and to date unrecognized, risk factor for stroke in Tanzania, especially in young and middle-aged individuals.
From the Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands (Q.d.M., A.J.v.d.V., P.G.d.G.); Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands (J.E.M., P.G.d.G., R.T.U.); North Tyneside General Hospital, North Shields (W.K.G., R.W.W.); Kilimanjaro Christian Medical Centre, Moshi, Tanzania (A.J.); Muhimbili University College Hospital, Dar-es-Salaam, Tanzania (F.M.); and Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne, United Kingdom (R.W.W.). quirijn.demast@radboudumc.nl.
Quirijn
Q
de Mast
From the Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands (Q.d.M., A.J.v.d.V., P.G.d.G.); Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands (J.E.M., P.G.d.G., R.T.U.); North Tyneside General Hospital, North Shields (W.K.G., R.W.W.); Kilimanjaro Christian Medical Centre, Moshi, Tanzania (A.J.); Muhimbili University College Hospital, Dar-es-Salaam, Tanzania (F.M.); and Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne, United Kingdom (R.W.W.).
Jessica E
JE
Molhoek
From the Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands (Q.d.M., A.J.v.d.V., P.G.d.G.); Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands (J.E.M., P.G.d.G., R.T.U.); North Tyneside General Hospital, North Shields (W.K.G., R.W.W.); Kilimanjaro Christian Medical Centre, Moshi, Tanzania (A.J.); Muhimbili University College Hospital, Dar-es-Salaam, Tanzania (F.M.); and Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne, United Kingdom (R.W.W.).
André J
AJ
van der Ven
From the Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands (Q.d.M., A.J.v.d.V., P.G.d.G.); Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands (J.E.M., P.G.d.G., R.T.U.); North Tyneside General Hospital, North Shields (W.K.G., R.W.W.); Kilimanjaro Christian Medical Centre, Moshi, Tanzania (A.J.); Muhimbili University College Hospital, Dar-es-Salaam, Tanzania (F.M.); and Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne, United Kingdom (R.W.W.).
William K
WK
Gray
From the Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands (Q.d.M., A.J.v.d.V., P.G.d.G.); Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands (J.E.M., P.G.d.G., R.T.U.); North Tyneside General Hospital, North Shields (W.K.G., R.W.W.); Kilimanjaro Christian Medical Centre, Moshi, Tanzania (A.J.); Muhimbili University College Hospital, Dar-es-Salaam, Tanzania (F.M.); and Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne, United Kingdom (R.W.W.).
Philip G
PG
de Groot
From the Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands (Q.d.M., A.J.v.d.V., P.G.d.G.); Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands (J.E.M., P.G.d.G., R.T.U.); North Tyneside General Hospital, North Shields (W.K.G., R.W.W.); Kilimanjaro Christian Medical Centre, Moshi, Tanzania (A.J.); Muhimbili University College Hospital, Dar-es-Salaam, Tanzania (F.M.); and Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne, United Kingdom (R.W.W.).
Ahmed
A
Jusabani
From the Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands (Q.d.M., A.J.v.d.V., P.G.d.G.); Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands (J.E.M., P.G.d.G., R.T.U.); North Tyneside General Hospital, North Shields (W.K.G., R.W.W.); Kilimanjaro Christian Medical Centre, Moshi, Tanzania (A.J.); Muhimbili University College Hospital, Dar-es-Salaam, Tanzania (F.M.); and Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne, United Kingdom (R.W.W.).
Ferdinand
F
Mugusi
From the Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands (Q.d.M., A.J.v.d.V., P.G.d.G.); Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands (J.E.M., P.G.d.G., R.T.U.); North Tyneside General Hospital, North Shields (W.K.G., R.W.W.); Kilimanjaro Christian Medical Centre, Moshi, Tanzania (A.J.); Muhimbili University College Hospital, Dar-es-Salaam, Tanzania (F.M.); and Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne, United Kingdom (R.W.W.).
Rolf T
RT
Urbanus
From the Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands (Q.d.M., A.J.v.d.V., P.G.d.G.); Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, The Netherlands (J.E.M., P.G.d.G., R.T.U.); North Tyneside General Hospital, North Shields (W.K.G., R.W.W.); Kilimanjaro Christian Medical Centre, Moshi, Tanzania (A.J.); Muhimbili University College Hospital, Dar-es-Salaam, Tanzania (F.M.); and Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne, United Kingdom (R.W.W.).
Richard W
RW
Walker
D000368:Aged; D000369:Aged, 80 and over; D017153:Antibodies, Anticardiolipin / Q000097:blood; D017152:Antibodies, Antiphospholipid / Q000097:blood*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015994:Incidence; D016682:Lupus Coagulation Inhibitor / Q000097:blood; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012424:Rural Population; D020521:Stroke / Q000097:blood / Q000453:epidemiology* / Q000276:immunology; D013636:Tanzania / Q000453:epidemiology; D014505:Urban Population
D017153:Antibodies, Anticardiolipin; D017152:Antibodies, Antiphospholipid; D016682:Lupus Coagulation Inhibitor
Africa; Tanzania; antiphospholipid antibodies; lupus anticoagulant; stroke; syphilis; β2-Glycoprotein I