Incidence of stroke and stroke subtypes in chronic obstructive pulmonary disease

• Published in: European journal of epidemiology Vol. 31; no. 2; pp. 159 - 168
• Main Authors: Söderholm, Martin, Inghammar, Malin, Hedblad, Bo, Egesten, Arne, Engström, Gunnar
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01.02.2016; Springer Netherlands; Springer Nature B.V
• Subjects: Aged; Asthma - complications; Asthma - epidemiology; Cardiology; Cerebral hemorrhage; Cerebral Hemorrhage - epidemiology; Cerebral Infarction - epidemiology; Chronic obstructive pulmonary disease; Cohort Studies; Comorbidity; Diabetes; Epidemiology; Female; Health risks; Health Sciences; Hemorrhage; Humans; Hypertension; Hälsovetenskap; Incidence; Infectious Diseases; International Statistical Classification of Diseases; Ischemia; Male; Medical and Health Sciences; Medicin och hälsovetenskap; Medicine; Medicine & Public Health; Middle Aged; Oncology; Predisposing factors; Public Health; Pulmonary Disease, Chronic Obstructive - complications; Pulmonary Disease, Chronic Obstructive - epidemiology; RESPIRATORY DISEASE; Risk Factors; Stroke; Stroke - epidemiology; Stroke - etiology; Strokes; Subarachnoid hemorrhage; Sweden - epidemiology; ANE, Sweden; Cerebral infarction; Stroke; Intracerebral haemorrhage; Subarachnoid haemorrhage; COPD
• ISSN: 0393-2990; 1573-7284; 1573-7284
• DOI: 10.1007/s10654-015-0113-7

It is uncertain whether the incidence of stroke is increased in patients with chronic obstructive pulmonary disease (COPD), and whether COPD is associated with all subtypes of stroke (i.e. ischemic stroke, intracerebral haemorrhage and subarachnoid haemorrhage). We evaluated the association between COPD and incidence of stroke in a nation-wide cohort study. All individuals between 40 and 84 years of age, hospitalised for COPD between 1987 and 2003 in Sweden were identified in the Swedish hospital discharge register. For each COPD patient (n = 103,419), one reference individual was randomly selected from the general population matched for year of birth, sex and county of residence. After excluding subjects with prior stroke, incidence rates during 10 years follow-up were calculated. Hazard ratios (HR) for stroke comparing COPD patients with reference subjects were estimated using Cox regression adjusting for demographics and comorbidities. Incidence of all-cause stroke (n events = 17,402) was significantly increased in COPD patients compared to reference individuals (HR 1.24, 95 % CI 1.19—1.28), especially during the first 2 years after COPD diagnosis (HR 1.46, 1.37—1.55). Incidences of ischemic stroke (HR 1.20, 1.15—1.25), intracerebral haemorrhage (HR 1.29, 1.16—1.43) and subarachnoid haemorrhage (HR 1.46, 1.16—1.85) were all increased in COPD patients. Incidences of all stroke subtypes are increased in COPD, especially during the first years after COPD diagnosis. The association was independent of several comorbidities, although residual confounding from smoking and hypertension cannot be excluded. A global evaluation of stroke risk factors seems warranted in patients with COPD.