Prospective Study of Type 1 and Type 2 Diabetes and Risk of Stroke Subtypes

Abstract

OBJECTIVE -The aim of this study was to examine the relationship between type 1 and type 2 diabetes and risk of stroke subtypes in women.RESEARCH DESIGN AND METHODS -We followed 116,316 women aged 30 -55 years in 1976 through 2002 for incidence of stroke. At baseline and through biennial follow-up, women were asked about their history and treatment of diabetes and other potential risk factors for stroke.RESULTS -During 2.87 million person-years of follow-up, 3,463 incident strokes occurred. In multivariate analyses, the incidence of total stroke was fourfold higher in women with type 1 diabetes (relative risk [RR] I n many (1-11) but not all (12-15) epidemiological studies, type 2 diabetes has been an important risk factor for ischemic stroke; however, relative risks (RRs) have varied widely, from 1.3 to 4.9 (1-11). The disparate RRs may be explained in part by differences in populations, definitions of diabetes, types of stroke studied, and analytical methods. The increased risk of stroke has been linked to the pathophysiological changes seen in the cerebral vessels of individuals with diabetes (1). In contrast, the association with hemorrhagic stroke remains controversial; reported associations have been positive (3,5), null (16,17), or even inverse (1,18 -20). Further, only a few small studies have examined the risk of stroke in patients with type 1 diabetes (18 -21), and this relationship remains unsettled. We used the large ongoing Nurses' Health Study to examine the risk of total stroke and its subtypes in women with type 1 or type 2 diabetes. RESEARCH DESIGN AND METHODS Data collectionThe Nurses' Health Study is an ongoing cohort established in 1976 when 121,701 female registered nurses aged 30 -55 years completed a mailed questionnaire on their health status and various lifestyle and behavioral risk factors. Participants complete biennial follow-up questionnaires to update risk factors and report newly diagnosed diseases including stroke. The biennial follow-up rate exceeds 90%, and mortality follow-up is estimated as Ͼ98% complete (22). The human research committees at the Harvard School of Public Health and Brigham and Women's Hospital approved the study. Ascertainment of strokeIncident strokes were defined as the first nonfatal stroke or stroke death occurring after the baseline questionnaire in 1976 but before 1 June 2002. Women who reported a stroke were asked for permission to access their medical records, which were reviewed by a physician without knowledge of the participant's exposure status. Women for whom medical record release was refused or for whom medical records were unavailable were classified as probable if supporting information was provided. Cerebrovascular pathology due to infection, trauma, or malignancy was excluded, as were "silent" strokes discovered only by radiological imaging. Stroke was classified according to criteria established by the National Survey of Stroke (23), which required evidence of a neurological deficit with sudden or rapid onset that persisted for Ͼ24 h or u...

Long‐Term Risk of Stroke in Patients With Type 1 and Type 2 Diabetes Following Coronary Artery Bypass Grafting

“…Diabetes is associated with a higher relative risk of stroke in women than in men,21 particularly in type 1 diabetes 22. In recent studies where patients with diabetes have been divided into type 1 and type 2 diabetes, a rather high incidence rate of stroke have been demonstrated both in type 1 and type 2 diabetes 23, 24. After separation of the diabetes types, an even further increased risk has been reported in type 1 diabetes 23, 24.…”

“…In recent studies where patients with diabetes have been divided into type 1 and type 2 diabetes, a rather high incidence rate of stroke have been demonstrated both in type 1 and type 2 diabetes 23, 24. After separation of the diabetes types, an even further increased risk has been reported in type 1 diabetes 23, 24. In our study, the association between type 1 and type 2 diabetes and risk of stroke was rather similar even if point estimates suggested a slightly stronger association between type 1 diabetes and risk of stroke.…”

Association of endothelial nitric oxide synthase polymorphisms and haplotypes with ischemic stroke in Korean individuals with or without diabetes mellitus

“…For example, type 2 diabetes mellitus (DM) is associated with a 2-to 5-fold increased risk for first or recurrent iS (3)(4)(5). The mechanisms behind the association are myriad, and include the effects of hyperglycemia on vascular tissues and coagulation, as well as aberrations in blood pressure regulation, endothelial function, lipid metabolism, vascular inflammation, lipid metabolism and smooth muscle cell proliferation.…”

Magnetic Resonance Neuroimaging Study of Brain Structural Differences in Diabetic Peripheral Neuropathy

“…Previous neuroimaging studies have focused on either acute cerebral disturbances of diabetes (14) in the context of metabolic abnormalities (e.g., hypoglycemia, ketoacidosis) (15) and stroke (16), or the long-term effects of diabetes on brain atrophy and cognition in the context of diabetes-related conditions (e.g., obesity, hyperinsulinemia) and dementia (17,18). While these metabolic and vascular abnormalities impact the brain as a whole, the aim of our study was to investigate differences in brain structure in subjects with DPN, a predominantly distal sensory motor neuropathy.…”