Table 1

Characteristics of studies included in the systematic review to assess risk of stroke and MI in adult patients with SLE compared with the general population or healthy controls

Author/year	Study design	Country	Study period	Source of SLE population	Source of comparison group	Number of patients SLE; control	Inclusion of fatal/non‑fatal events	% Female SLE population	Mean/median age (years) SLE; control	Overall estimate risk of bias	Outcomes reported	Relative risk measure reported
Arkema 2017²⁸	Cohort study	Sweden	2003–2013	National Patient Register	Total population register	3390; 16 730	Fatal and/or non-fatal	85%	50; 49	Low	Ischaemic stroke, intracerebral haemorrhage, subarachnoid haemorrhage, unspecified stroke, composite stroke	Rate difference
Avina-Zubieta 2017²⁹	Cohort study	Canada	1996–2010	Population data British Columbia	Same as SLE	4912; 49 611	Fatal and/or non-fatal	86%	49; 49	Low	Ischaemic stroke, MI	HR
Barnado 2018⁴⁸	Cohort study	USA	NR	The Synthetic Derivative (SD) database of Vanderbilt University, Tennessee	Same as SLE	1097; 5735	Non-fatal	90%	40; NR	Low	MI	OR
Bengtsson 2012³⁰	Cohort study	Sweden	2001–2007	19 specialist departments, 140 primary healthcare centres and one private practice	National Board of Health and Statistics Sweden	275; 517	Fatal and/or non-fatal	85%	51; 48	Low	Composite stroke, MI	SIR
Bernatsky 2006a⁶	Cohort study	Multinational	1958–2001	23 collaborating lupus centres in seven countries	Population rates (SMR)	9547; NA	Fatal	90%	NR	Low	Composite stroke	SMR
Bernatsky 2006b⁵	Cohort study	Canada	1958–2001	10 collaborating CaNIOS lupus centres across Canada	Population rates (SMR)	2688; NA	Fatal	90%	NR	Moderate	Ischaemic stroke, subarachnoid haemorrhage, composite stroke	SMR
Björnådal 2004⁷	Cohort study	Sweden	1964–1995	The Hospital Discharge Register	Cause of death register (SMR)	4737; NA	Fatal	78%	NR	Moderate	Composite stroke	SMR
Chang 2013³¹	Cohort study	Taiwan	2000–2006	National Health Insurance research database	Same as SLE	16 967; 16 967	Fatal and/or non-fatal	90%	36; 36	Low	Subarachnoid haemorrhage	IRR
Chiu 2012³²	Cohort study	Taiwan	2000–2007	National Health Insurance research database	Same as SLE	11 637; 58 185	Non-fatal	89%	41; 41	Low	Ischaemic stroke	HR
Cook 2018⁴⁹	Cohort study	UK	2007–2010	UK Biobank	Same as SLE	559; 2236	Non-fatal	89%	56; NR	High	Composite stroke/MI	HR (and SMR)
Dregan 2017³³	Cross-sectional study	UK	2006–2010	UK Biobank	Same as SLE	654; 483 559	Fatal and/or non-fatal	89%	42; 57	High	Composite stroke	RR
Faurschou 2011³⁴	Cohort study	Denmark	1977–2006	Danish SLE cohort established in 1995 and recruited from eight clinical centres	Danish National Hospital Register (event rate calculated for background population)	104; NA	Fatal and/or non-fatal	80%	31; NR	Low	MI	O:E ratio (95% CI)
Hak 2009³⁵	Cohort study	USA	1976–2004	Nurses’ Health Study	Same as SLE	148; 108 968	Fatal and/or non-fatal	100%	56; 56	Low	Composite stroke, MI	Rate ratio
Hermansen 2017³⁶	Cohort study	Denmark	1995–2011	The Danish National Patient Registry & Danish Register of Causes of Death	Same as SLE	NR; NR	Fatal and/or non-fatal	86%	48 (no LN), 40 (with LN); 48 (no LN), 40 (with LN)	Low	Composite stroke, MI	HR
Kim 2017³⁷	Cohort study	USA	1999–2016	Explorys platform (26 US healthcare systems)	Same as SLE	95 400; 45 189 140	Non-fatal	89%	NR	Low	MI	Relative risk
Krishnan 2005³⁸	Cross-sectional study	USA	2001–2002	Healthcare Cost and Utilization Project—Nationwide Inpatient Sample	Same as SLE (hospitalisations without mention of lupus)	25 704; 3 130 405	Non-fatal	90%	38; 38	High	Ischaemic stroke, intracerebral haemorrhage, subarachnoid haemorrhage, composite stroke	OR
Lim 2018⁵⁰	Cohort study	South Korea	2008–2014	Korean National Health Insurance Service (NHIS) database	Same as SLE	18 575; 92 875	Non-fatal	91%	NR	Low	Composite stroke/MI	HR
Lin 2014³⁹	Cohort study	Taiwan	2000–2004	National Health Insurance Research Database	Same as SLE	1207; 9656	Fatal and/or non-fatal	82%	NR	Low	MI	IRR
Liou 2014⁴⁰	Cohort study	Taiwan	2004–2007	The Longitudinal Health Insurance Database 2005 and Registry for Beneficiaries	Same as SLE	621; 2484	Non-fatal	89%	NR	Low	Ischaemic stroke, composite stroke	HR
Manzi 1997⁴¹	Cohort study	USA	1980–1993	The University of Pittsburgh Medical Center	Framingham Offspring Study	498; 2208	Non-fatal	100%	NR	Low	MI	Relative risk
Mok 2009⁴²	Cohort study	China (Hong Kong)	1999–2007	Tuen Mun Hospital	Expected from regional population	490; 1 060 000	Fatal and/or non-fatal	92%	33; NR	High	Ischaemic stroke, intracerebral haemorrhage, composite stroke	SIR
Ramagopalan 2013⁴³	Cohort study	England	1999–2011	Hospital Episode Statistics	Same as SLE	25 576; NR	Fatal and/or non-fatal	86%	NR	Low	Subarachnoid haemorrhage	Rate ratio
Rees 2016⁴⁴	Cohort study	UK	1999–2012	Clinical Practice Research Datalink	Same as SLE	7033; 26 683	Non-fatal	86%	48; 48	Low	Composite stroke	IRR
Wang 2012⁴⁵	Cohort study	Taiwan	1997–2008	Taiwan’s National Health Insurance research database	Same as SLE	13 689; 54 756	Non-fatal	88%	35; 35	Low	Ischaemic stroke, intracerebral haemorrhage, subarachnoid haemorrhage haemorrhagic stroke, composite stroke	HR
Ward 1999⁴⁷	Cross-sectional study	USA	1991–1994	California Office of Statewide Health Planning and Development	Same as SLE	NR; NR	Non-fatal	100%	NR	High	Composite stroke, MI	HR
Zoller 2012⁴⁶	Cohort study	Sweden	1987–2008	Several national Swedish data registers	Population rates	4179; NR	Non-fatal	82%	NR	Low	Ischaemic stroke, intracerebral haemorrhage	SIR

CaNIOS, Canadian Network for Improved Outcomes in Systemic Lupus Erythematosus; IRR, incident rate ratio; LN, lupus nephritis; MI, myocardial infarction; NA, not applicable; NR, not reported; O:E ratio, ratio of observed to expected events; RR, risk ratio; SIR, standardised incidence ratio; SLE, systemic lupus erythematosus; SMR, standardised mortality ratio.