Table 1

Characteristics of the studies included in the meta-analysis to assess the risk of stroke associated with SLE

First author and year of publicationStudy periodCountryData source(s)SLE (n)Non-SLE (n)Stroke definitions used as outcomes*
Agha, 2014131996–2010CanadaMedical Services Plan, British Columbia4 97249 948Ischaemic stroke
Bengtsson, 201292001–2007SwedenN. Sweden Clinical Cohort, medical biobank of N. Sweden, national inpatient register277520Any stroke
Chang, 2013142000–2006TaiwanTaiwan National Health Insurance Research Database16 96716 967Subarachnoid haemorrhage
Chiu, 2012152000–2007TaiwanTaiwan National Health Insurance Research Database11 63758 185Ischaemic stroke
Hak, 2009161976–2004USANurses’ Health Study148119 332Any stroke
Liou, 2014172004–2007TaiwanTaiwan Longitudinal Health Insurance Database 200524842484Any stroke, ischaemic stroke and intracerebral haemorrhage†
Mok, 2009181999–2007ChinaHospital-based SLE cohort and stroke events admitted to the same hospital to obtain general population rates from the hospital catchment area490Not reportedAny stroke, ischaemic and haemorrhagic stroke (intracerebral and subarachnoid haemorrhage combined)
Ramagopalan, 2013191999–2011UKEnglish national Hospital Episode Statistics25 576≈7 600 000Subarachnoid haemorrhage
Wang, 2012201997–2008TaiwanTaiwan National Health Insurance Research Database13 68954 756Any stroke, ischaemic stroke, intracerebral and subarachnoid haemorrhage
Zöller, 2012211987–2008SwedenSwedish national inpatient register and total population of Sweden as reference group4179Not reportedIschaemic stroke and intracerebral haemorrhage

  • *All studies used ICD codes to identify stroke except for Hak et al in which stroke was self-reported and a medical record review was conducted.

  • †Liou et al did not report a separate HR for intracerebral haemorrhage. They only reported that it was not significantly different from that of the general population.

  • ICD, International Classification of Diseases; SLE, systemic lupus erythematosus.