Oral contraceptives, pregnancy and the risk of cerebra1 thromboembolism: the influence of diabetes, hypertension, migraine and previous thrombotic disease

Abstract

Objective To assess the risk of developing cerebral thromboembolism among pregnant women and among fertile women with hypertension, migraine, diabetes, and previous thrombotic disease, and to investigate the interaction of these risk factors with the use of oral contraceptives. Design A retrospective case‐control study. Setting All gynaecological, medical, neurological, and neurosurgical departments in Danish hospitals. Subjects Seven hundred and ninety‐four women in Denmark aged 15 to 44 who suffered a cerebral thromboembolic attack during the period 1985 to 1989 and 1588 age‐matched, randomly selected controls. Response Of the 692 case and 1584 control questionnaires sent out, 590 (85.1%) and 1396 (88.1 %), respectively, were returned. Of the 590 cases, nine had had cerebral thrombosis before 1980, 15 refused to participate, 44 had a revised diagnosis (primarily multiple sclerosis) and 25 had an unreliable diagnosis, leaving 497 with a reliable cerebral thromboembolic diagnosis. Among the 1396 controls, 26 either refused to participate, were mentally handicapped, lived abroad or returned an uncompleted questionnaire, leaving 1370 controls included in the study. Results After multivariate analysis, pregnancy implied an odds ratio (OR) for a cerebral thromboembolic attack of 1.3 (nonsignificant), diabetes an OR of 5.4 (P < 0.001), hypertension an OR of 3.1 (P < 0.001) and migraine an OR of 2.8 (P < 0.01). Women with previous non‐cerebral thrombotic disease had an OR for cerebral thrombo‐embolism of 5.3 (P < 0.001). Women with other predisposing medical diseases had an OR of 8.3 (P < 0.001). These ORs were identical among users and non‐users of combined oral contraceptives. Conclusion In this study pregnancy implied a non‐significant elevated odds ratio of 1.3 for cerebral thromboembolism whereas diabetes, hypertension, migraine and past thromboembolic events increased the risk of cerebral thromboembolism significantly. Women with these increased thrombotic risks should use oestrogen‐containing oral contraceptives only after careful considerations of the risks, if at all.

Primary Prevention of Ischemic Stroke

“…Some data suggest that the total stroke risk may be more than additive for combinations of smoking, migraine with aura, and age Ͼ35 years, but the issue remains unsettled for low-dose OCs. 102,389,390,[397][398][399] The absolute increase in stroke risk with low-dose OCs, if one exists, is small. 390,392 Estimates of the incidence of ischemic stroke in young women range from 0.9 to Ϸ10 per 100 000.…”

Migraine and motion sickness: What is the link?

“…Various co-morbid conditions, which necessarily involve brainstem circuitry, have been linked with migraine such as sleep apnoea (Proceta and Dalessio, 1995), asthma (Medina and Diamond, 1976) and stroke (Lidegaard, 1995), but the closest fit in terms of symptoms would appear to be motion sickness. These symptoms arise due to a mismatch between visual, proprioceptive or vestibular cues of motion, possibly to warn the body of a potential threat to homeostasis.…”

Hypertension in women

“…In a study of women with first stroke, Haapaniemi et al 98 found OC use to be an independent risk factor for ischaemic brain infarction. Among 15 to 44-yearold OC users who had had a cerebral thromboembolic attack studied by Lidegaard 99 during a 5-year period in Denmark, the risk of stroke was six times greater among diabetic women who had had previous thrombotic disease, and three times greater among women with hypertension or migraine. Thus, women with multiple concomitant cardiovascular risk factors should be carefully screened and monitored prior to and during OC use.…”