Bea C Tanis

Prothrombotic conditions, oral contraceptives, and the risk of ischemic stroke

Summary.  Background: The role of inherited prothrombotic conditions, including factor V Leiden (FV G1691A), prothrombin G20210A, and the methylenetetrahydrofolate reductase (MTHFR) C677T genotype, in the pathogenesis of ischemic stroke is not well established. The effects of these factors may be potentiated by the use of oral contraceptives, analogous to observations in venous thrombosis. Methods: Patients (n = 193) were women aged 20–49 years with ischemic stroke. Controls (n = 767) were women without arterial thrombosis stratified for age, calendar year of the index event, and residence. The relative risk of ischemic stroke was estimated with unconditional logistic regression, adjusted for stratification variables. Findings: Factor V Leiden and MTHFR 677TT were more common in patients than in controls [odds ratio (OR): 1.8; 95% confidence interval (CI): 0.9–3.6 respectively OR: 1.5; 95% CI: 0.9–2.6]. The frequency of prothrombin G20210A was similar in cases and controls. Carriers of FV Leiden using oral contraceptives had a 11.2‐fold (95% CI: 4.3–29.0) higher risk of ischemic stroke than women without either risk factor. Women with MTHFR 677TT using oral contraceptives had a 5.4‐fold (95% CI: 2.4–12.0) higher risk than women without these risk factors. Interpretation: These data suggest that carriers of FV Leiden or MTHFR 677TT who use oral contraceptives have an increased risk of ischemic stroke. When these findings are confirmed, a cost‐effectiveness analysis should indicate whether ischemic stroke could be prevented with genetic testing before the start of oral contraceptives.

The RATIO study: oral contraceptives and the risk of peripheral arterial disease in young women

Summary.  With regard to oral contraceptives, much research has concentrated on venous thrombosis and on the coronary and cerebral forms of atherosclerotic disease, while peripheral arterial disease (PAD) has received little attention. In this case‐control study, we assessed oral contraceptive use and the risk of PAD in young women using a population‐based case‐control study. The women were 18–49 years of age, and had been admitted to a collaborating hospital between January 1990 and October 1995, and had a diagnosis of PAD. Participants were patients with PAD (n = 152), and control women (n = 925), identified by random digit dialing. The diagnosis of PAD was based almost exclusively on intra‐arterial angiography. Patients and control subjects filled out the same structured questionnaire, which included questions on medical history, cardiovascular risk factors, and contraceptive use. The adjusted odds ratio for PAD in women using any type of oral contraceptives vs. no use, was 3.8 (95% CI 2.4–5.8). When first generation oral contraceptive use was compared with no use, the odds ratio was 8.7 (95% CI 3.6–21.3). For second and third generation oral contraceptives, the adjusted odds ratios (compared with non‐users) were 2.6 (95% CI 1.4–4.9) and 3.0 (95% CI 1.4–6.6), respectively. This is the first study on oral contraceptive use and PAD in humans. All types of oral contraceptives were associated with an increased risk of PAD.

Dutch women with a low birth weight have an increased risk of myocardial infarction later in life: a case control study

BackgroundTo investigate whether low birth weight increases the risk of myocardial infarction later in life in women.MethodsNationwide population-based case-control study. Patients and controls: 152 patients with a first myocardial infarction before the age of 50 years in the Netherlands. 568 control women who had not had a myocardial infarction stratified for age, calendar year of the index event, and area of residence.ResultsBirth weight in the patient group was significantly lower than in control women (3214 vs. 3370 gram, mean difference -156.3 gram (95%CI -9.5 to -303.1). The odds ratio for myocardial infarction, associated with a birth weight lower than 3000 gram (20th percentile in controls) compared to higher than 3000 gram was 1.7 (95%CI 1.1–2.7), while the odds ratio for myocardial infarction for children with a low birth weight (< 2000 g) compared to a birth weight ≥ 2000 g was 2.4 (95%CI 1.0 – 5.8). Both figures did not change after adjustment for putative confounders (age, education level, body mass index, waist-hip ratio, hypertension, diabetes, hypercholesterolemia, smoking, and family history of cardiovascular disease).ConclusionsLow birth weight is associated with an increased risk of myocardial infarction before age of 50 in Dutch women.

Novel risk factors for peripheral arterial disease in young women

PURPOSE To investigate traditional and novel risk factors (homocysteine and C-reactive protein levels, and exposure to infections) for peripheral arterial disease in young women. SUBJECTS AND METHODS In a multicenter, population-based, case-control study, 212 young women (mean [+/- SD] age, 48.2 +/- 7.0 years) with peripheral arterial disease and 475 healthy control women (mean age, 45.5 +/- 8.1 years) completed a standardized questionnaire and provided blood samples. Peripheral arterial disease was angiographically confirmed if a stenotic lesion (more than 50% reduction of the lumen) was present in at least one major peripheral artery. Hyperhomocysteinemia was defined as a nonfasting plasma homocysteine level exceeding the 90th percentile of the control group. History of infectious diseases was determined by questionnaire. RESULTS Elevated C-reactive protein levels were associated with an increased likelihood of peripheral arterial disease (odds ratio [OR] = 3.9; 95% confidence interval [CI]: 1.8 to 8.5 for women in the third quartile; OR = 3.1; 95% CI: 1.4 to 6.8 for women in the fourth quartile; both comparisons with women in the first quartile). Hyperhomocysteinemia was not associated with a significantly increased risk of peripheral arterial disease (OR = 1.6; 95% CI: 0.9 to 3.0). A history of chickenpox, shingles, mumps, pneumonia, chronic bronchitis, peptic ulcer, or periodontitis was independently related to peripheral arterial disease, with adjusted odds ratios varying from 1.7 (95% CI: 1.0 to 3.1) for mumps to 3.4 (95% CI: 1.5 to 7.7) for peptic ulcer. The risk of peripheral arterial disease increased with the number of these infections; exposure to five or more infections increased the odds 3.7-fold (95% CI: 1.7 to 8.2). This association was not affected by the level of C-reactive protein. CONCLUSION Our results do not support a strong relation between homocysteine and peripheral arterial disease in young women. However, an elevated C-reactive protein level and several types of symptomatic infection were associated with peripheral arterial disease.

Folate, homocysteine levels, methylenetetrahydrofolate reductase (MTHFR) 677C T variant, and the risk of myocardial infarction in young women: effect of female hormones on homocysteine levels

Summary.  In young women data are limited about the association between myocardial infarction (MI) and hyperhomocysteinemia, low folate or methylenetetrahydrofolate reductase (MTHFR) genotypes. The effect of oral contraceptive (OC) use on plasma homocysteine levels is not clear. We assessed the association between hyperhomocysteinemia, low folate, MTHFR 677TT mutation and risk of MI, and we investigated the effect of OC use on homocysteine levels in controls. In 181 patients with a first MI and 601 controls 18–49 years of age from a population‐based case–control study, non‐fasting blood samples were available. The homozygote mutant allele (TT) was detected in 12% of the patients and in 10% of controls. The odds ratio (OR) for MI in TT patients compared with the wild‐type (CC) controls was 1.3 [95% confidence interval (CI) 0.8, 2.3]. For all MTHFR genotypes combined, the OR for MI in the lowest quartile of folate (<5.4 nmol L−1) compared with the highest quartile (>10.4 nmol L−1) was 3.0 (95% CI 1.7, 5.1). A 2‐fold increased risk of MI was found in women with the TT genotype who had folate levels below the median of 7.4 nmol L−1 compared with CC genotype and folate levels above the median (OR = 2.0; 95% CI 1.0, 3.7). Mean homocysteine levels were 12.2 µmol L−1 in OC users and 12.3 µmol L−1 in non‐users. Only at the 97.5 percentile (cut‐off 21.0 µmol L−1) was the adjusted OR for higher vs. lower homocysteine levels increased by 2.8‐fold (95% CI 1.2, 6.8). Low folate is a risk factor for MI, particularly in women with the MTHFR 677TT genotype. Homocysteine levels were not influenced by OC use.

Functional health and well-being of relatively young women with peripheral arterial disease is decreased but stable after diagnosis.

OBJECTIVE This study was undertaken to investigate the extent to which health-related quality of life (HQOL) is reduced in young women with peripheral arterial disease (PAD) compared with age-matched and gender-matched control subjects. Moreover, potential determinants of HQOL in young women with PAD were studied, ie, traditional cardiovascular risk factors, location of stenosis and time since diagnosis. METHODS This was a population-based case-control study. Subjects were 208 young (<50 years) women with PAD diagnosed at angiography and 471 population-based age-matched and gender-matched control subjects. All participants completed the RAND-36 questionnaire, which produces a HQOL profile. The questionnaire contains 36 items that assess 8 domains of HQOL. Each domain is given a mean score ranging from 0 to 100, with higher scores indicative of better quality of life. RESULTS PAD had a deleterious effect on HQOL in young women. Ability to deal with the physical requirements of daily life was affected, and physical capabilities limited activity to a considerable extent. Mean differences observed for 2 domains, ie, Physical functioning and Role-physical, were -25.1 (95% confidence interval [CI], -28.8,-21.4) and -22.5 (95% CI, -28.9,-16.0). Within the group of young women with PAD, HQOL did not depend on age, smoking, hypercholesterolemia, or education. However, women with hyperglycemia, hypertension, or increased body mass index scored lower on 1 or more domains of RAND-36. Location of stenosis was also related to HQOL; patients with more proximal stenosis scored slightly higher on the domain Physical functioning, compared with women with more distal stenosis. Time (0-10 years) between diagnosis (1990-1999) and when RAND-36 was filled out (2000) is related to score on the Mental health domain; score increases over time. Scores on the other 7 domains of HQOL showed no significant relation to duration of disease. CONCLUSION Quality of life in young women with PAD was statistically significant diminished for all domains of RAND-36 in comparison with HQOL in healthy age-matched control subjects. HQOL of patients with recently diagnosed PAD is comparable to that of patients in whom the diagnosis was made several years previously. Effective therapy might stabilize, albeit not improve, quality of life in this specific patient population.

Increased pregnancy loss in young women with aortoiliac disease

BACKGROUND During clinical evaluation of young women with peripheral arterial occlusive disease, we were surprised by the high prevalence of pregnancy loss in women with segmental stenosis confined to the aortoiliac segment. We wondered if increased occurrence of miscarriage is the result of high expression of vascular and obstetrical risk factors in these patients, or if it is related to localization of disease. In a case-control study designed to investigate risk factors for peripheral arterial occlusive disease in young women, we assessed the risk of miscarriage in these patients according to level of obstruction. METHODS A total of 202 female patients, aged 18-49 years and 466 healthy control women from a population based case-control study, donated venous blood samples and filled out a structured questionnaire concerning classical cardiovascular risk factors and obstetrical history. In all patients, diagnosis of peripheral arterial occlusive disease was confirmed by intra-arterial angiography. Patients were classified into two groups: those with and those without stenosis of the aortoiliac segment (aortoiliac disease). RESULTS In 77 of the 202 patients (38%) with peripheral arterial occlusive disease, the obstruction was confined to the aortoiliac segment. The occurrence of miscarriage was high (42%) in young women with aortoiliac disease. Compared to healthy controls, the risk of miscarriage increased 3-fold (OR 3.1; 95% CI 1.8-5.6) in these patients. Adjustment for obstetrical and vascular risk factors did not affect the risk estimate. CONCLUSION This is the first study that identifies aortoiliac disease as a risk factor for pregnancy loss in young women. The risk of miscarriage is increased 3-fold in women with aortoiliac disease. The presence of vascular and obstetrical risk factors did not affect the strength of the association. Pregnancy loss could be the first sign of insufficient aortic circulation in these patients.