Weight gain in early pregnancy and risk of gestational diabetes mellitus among Latinas.

AIM: To evaluate the association between gestational weight gain (GWG) in early pregnancy and incidence of abnormal glucose tolerance (AGT) and gestational diabetes mellitus (GDM) among Latinas. METHODS: We conducted a retrospective cohort study of 2039 Latinas using pooled data from two medical centres in Massachusetts. Gestational weights were abstracted from medical records and GWG was categorized as low, appropriate and excessive according to 2009 Institute of Medicine Guidelines. Diagnosis of AGT and GDM was confirmed by study obstetricians. RESULTS: A total of 143 women (7.0%) were diagnosed with GDM and 354 (17.4%) with AGT. After adjusting for age and study site, women with low GWG up to the time of GDM screen had a lower odds of GDM (OR: 0.51, 95% CI: 0.29-0.92). Among overweight women, women with excessive first-trimester GWG had 2-fold higher odds of AGT (OR: 1.96, 95% CI: 1.17-3.30) and GDM (OR: 2.07, 95% CI: 1.04-4.12) compared to those with appropriate GWG; however, these findings were not significant among normal weight or obese women. CONCLUSION: Among Latinas, low GWG up to the time of GDM screen was associated with lower odds of AGT and GDM, while excessive GWG among overweight women was associated with higher odds. Findings highlight need for interventions in early pregnancy to help women meet GWG guidelines and to moderate GWG among overweight Latinas.

Moderate intensity sports and exercise is associated with glycaemic control in women with gestational diabetes.

AIM: To assess the association of regular, unsupervised sports and exercise during pregnancy, by intensity level, with glycaemic control in women with gestational diabetes (GDM). METHODS: Prospective cohort study of 971 women who, shortly after being diagnosed with GDM, completed a Pregnancy Physical Activity Questionnaire assessing moderate and vigorous intensity sports and exercise in the past 3 months. Self-monitored capillary glucose values were obtained for the 6-week period following the questionnaire, with optimal glycaemic control defined≥80% values meeting the targets<5.3mmol/L for fasting and <7.8mmol/L 1-hour after meals. Logistic regression estimated the odds of achieving optimal control; linear regression estimated activity level-specific least square mean glucose, as well as between-level mean glucose differences. RESULTS: For volume of moderate intensity sports and exercise ([MET×hours]/week), the highest quartile, compared to the lowest, had significantly increased odds of optimal control (OR=1.82 [95% CI: 1.06-3.14] P=0.03). There were significant trends for decreasing mean 1-hour post breakfast, lunch and dinner glycaemia with increasing quartile of moderate activity (all P<0.05). Any participation in vigorous intensity sports and exercise was associated with decreased mean 1-hour post breakfast and lunch glycaemia (both P<0.05). No associations were observed for fasting. CONCLUSION: Higher volumes of moderate intensity sports and exercise, reported shortly after GDM diagnosis, were significantly associated with increased odds of achieving glycaemic control. Clinicians should be aware that unsupervised moderate intensity sports and exercise performed in mid-pregnancy aids in subsequent glycaemic control among women with GDM.

A pregnancy lifestyle intervention to prevent gestational diabetes risk factors in overweight Hispanic women: a feasibility randomized controlled trial.

AIMS: To pilot the feasibility of a prenatal lifestyle intervention to modify physical activity and diet among pregnant overweight and obese Hispanic women, with the aim of reducing risk factors for gestational diabetes mellitus. METHODS: Women were randomized either to a lifestyle intervention (n = 33, 48.5%), consisting of a culturally and linguistically modified, motivationally targeted, individually tailored 6-month prenatal programme, or to standard care (n = 35, 51.5%). Bilingual and bicultural health educators encouraged women to achieve guidelines for physical activity, decrease saturated fat and increase dietary fibre. Outcomes included gestational weight gain, infant birth weight and biomarkers associated with insulin resistance. RESULTS: Patient retention up to delivery was 97% in both study groups. The lifestyle intervention attenuated the pregnancy-associated decline in moderate-intensity physical activity, but differences between groups were not significant (mean ± se -23.4 ± 16.6 vs -27.0 ± 16.2 metabolic equivalent of task h/week; P = 0.88). Vigorous-intensity activity increased during the course of pregnancy in the lifestyle intervention group (mean ± se 1.6 ± 0.8 metabolic equivalent of task h/week) and declined in the standard care group (-0.8 ± 0.8 metabolic equivalent of task h/week; P = 0.04). The lifestyle intervention group also had slightly lower gestational weight gain and infant birth weights compared with the standard care group; however, these differences were not statistically significant. There were no statistically significant differences in biomarkers of insulin resistance between groups. CONCLUSIONS: Findings suggest that a motivationally matched lifestyle intervention is feasible and may help attenuate pregnancy-related decreases in vigorous physical activity in a population of overweight and obese Hispanic women. The intervention protocol can readily be translated into clinical practice in underserved and minority populations.

Perceived psychosocial stress and glucose intolerance among pregnant Hispanic women.

AIM: Prior literature suggests a positive association between psychosocial stress and the risk of diabetes in non-pregnant populations, but studies during pregnancy are sparse. We evaluated the relationship between stress and glucose intolerance among 1115 Hispanic (predominantly Puerto Rican) prenatal care patients in Proyecto Buena Salud, a prospective cohort study in Western Massachusetts (2006-2011). METHODS: Cohen's Perceived Stress Scale (PSS-14) was administered in early (mean = 12.3 weeks gestation; range 4.1-18 weeks) and mid- (mean = 21.3 weeks gestation; range 18.1-26 weeks) pregnancy. Participants were classified as having a pregnancy complicated by gestational diabetes mellitus, impaired glucose tolerance, and abnormal glucose tolerance, based on the degree of abnormality on glucose tolerance testing between 24 and 28 weeks of gestation. RESULTS: The prevalence of gestational diabetes mellitus, impaired glucose tolerance, and abnormal glucose tolerance was 4.1%, 7.2%, and 14.5%, respectively. Absolute levels of early or mid-pregnancy stress were not significantly associated with glucose intolerance. However, participants with an increase in stress from early to mid-pregnancy had a 2.6-fold increased odds of gestational diabetes mellitus (95% confidence intervals: 1.0-6.9) as compared to those with no change or a decrease in stress after adjusting for age and pre-pregnancy body mass index. In addition, every one-point increase in stress scores was associated with a 5.5mg/dL increase in screening glucose level (ß=5.5; standard deviation=2.8; P=0.05), after adjusting for the same variables. CONCLUSION: In this population of predominantly Puerto Rican women, stress patterns during pregnancy may influence the risk of glucose intolerance.

Associations between race, lifecourse socioeconomic position and prevalence of diabetes among US women and men: results from a population-based panel study.

BACKGROUND: Few studies have examined the degree to which racial disparities in the development of diabetes are accounted by differences in lifecourse socioeconomic position (SEP). We assessed the association between race, lifecourse SEP measures and prevalence of diabetes in a representative US sample of black and white adults. METHODS: A generalised estimating equations approach was used with a sample of 3497 adults from the Americans' Changing Lives study. Sex-specific models were calculated to compute prevalence ratios (PR) for associations of race and SEP with self-reported diagnoses of diabetes. RESULTS: For men, childhood and adult SEP were unrelated to diabetes, and adjustment for lifecourse SEP had little effect on the excess diabetes in blacks (PR=1.56, 95% CI 1.11 to 2.21). Adjustment for measures of lifecourse SEP reduced the PR for the association between race and diabetes in women from 1.96 (95% CI 1.52 to 2.54) to 1.40 (95% CI 1.04 to 1.87) with the respondent's education responsible for most of the reduction in the association. However, diabetes was also inversely associated with father's education, and low SEP throughout the lifecourse was associated with a nearly threefold increase in diabetes (PR=2.89, 95% CI 2.10 to 3.99). CONCLUSIONS: Racial disparities in diabetes existed among both men and women, but lifecourse SEP was related to diabetes only among women. The pathway and cumulative hypotheses for lifecourse SEP effects on diabetes may be especially salient for women.

Physical activity before and during pregnancy and risk of abnormal glucose tolerance among Hispanic women.

AIM: Women diagnosed with abnormal glucose tolerance and gestational diabetes mellitus are at increased risk for subsequent type 2 diabetes, with higher risks in Hispanic women. Studies suggest that physical activity may be associated with a reduced risk of these disorders; however, studies in Hispanic women are sparse. METHODS: We prospectively evaluated this association among 1241 Hispanic participants in Proyecto Buena Salud. The Pregnancy Physical Activity Questionnaire was used to assess pre, early, and mid pregnancy physical activity. Medical records were abstracted for pregnancy outcomes. RESULTS: A total of 175 women (14.1%) were diagnosed with abnormal glucose tolerance and 57 women (4.6%) were diagnosed with gestational diabetes. Increasing age and body mass index were strongly and positively associated with risk of gestational diabetes. We did not observe statistically significant associations between total physical activity or meeting exercise guidelines and risk. However, after adjusting for age, BMI, gestational weight gain, and other important risk factors, women in the top quartile of moderate-intensity activity in early pregnancy had a decreased risk of abnormal glucose tolerance (odds ratio=0.48, 95% Confidence Interval 0.27-0.88, Ptrend=0.03) as compared to those in the lowest quartile. Similarly, women with the highest levels of occupational activity in early pregnancy had a decreased risk of abnormal glucose tolerance (odds ratio=0.48, 95% Confidence Interval 0.28-0.85, Ptrend=0.02) as compared to women who were unemployed. CONCLUSION: In this Hispanic population, total physical activity and meeting exercise guidelines were not associated with risk. However, high levels of moderate-intensity and occupational activity were associated with risk reduction.

Exercise and diabetes.

As rates of diabetes mellitus and obesity continue to increase, physical activity continues to be a fundamental form of therapy. Exercise influences several aspects of diabetes, including blood glucose concentrations, insulin action and cardiovascular risk factors. Blood glucose concentrations reflect the balance between skeletal muscle uptake and ambient concentrations of both insulin and counterinsulin hormones. Difficulties in predicting the relative impact of these factors can result in either hypoglycemia or hyperglycemia. Despite the variable impact of exercise on blood glucose, exercise consistently improves insulin action and several cardiovascular risk factors. Beyond the acute impact of physical activity, long-term exercise behaviors have been repeatedly associated with decreased rates of type 2 diabetes. While exercise produces many benefits, it is not without risks for patients with diabetes mellitus. In addition to hyperglycemia, from increased hepatic glucose production, insufficient insulin levels can foster ketogenesis from excess concentrations of fatty acids. At the opposite end of the glucose spectrum, hypoglycemia can result from excess glucose uptake due to either increased insulin concentrations, enhanced insulin action or impaired carbohydrate absorption. To decrease the risk for hypoglycemia, insulin doses should be reduced prior to exercise, although some insulin is typically still needed. Although precise risks of exercise on existing diabetic complications have not been well studied, it seems prudent to consider the potential to worsen nephropathy or retinopathy, or to precipitate musculoskeletal injuries. There is more substantive evidence that autonomic neuropathy may predispose patients to arrhythmias. Of clear concern, increased physical activity can precipitate a cardiac event in those with underlying CAD. Recognizing these risks can prompt actions to minimize their impact. Positive actions that are part of exercise programs for diabetic patients emphasize SMBG, foot care and cardiovascular functional assessment. SMBG provides critical information on the impact of exercise and is recommended for all patients before, during and after exercise. More frequent monitoring (and for longer periods following exercise) is recommended for those with hypoglycemia unawareness or those performing high-intensity exercise. Preventing the sequelae of an exercise-induced severe hypoglycemic reaction can be as simple as carrying glucose tablets or gel, a diabetic identification bracelet or card, or exercising with an individual who is aware of the circumstances. In addition to blood glucose concentrations, proper foot care is critical to people with diabetes who exercise and includes considering type of shoe, type of exercise, inspection of skin surfaces and appropriate evaluation and treatment of lesions (calluses and others). Those with severe neuropathy can consider alternatives to weight-bearing exercises. Precipitation of clinical CAD is of great concern for all diabetic patients participating in exercise activities. Although a sufficiently sensitive and specific screening test for coronary disease has not been identified, those planning an exercise program of moderate intensity or greater should be evaluated. Initial cardiac assessment should include exercise testing as well as identifying risk for autonomic neuropathy. In addition to noting maximal heart rate and blood pressure as well as ischemic changes, exercise tolerance testing can identify anginal thresholds and patients with asymptomatic ischemia. Those without symptoms should be counseled regarding target pulse rates to avoid inducing ischemia. Ischemic changes need to be evaluated for either further diagnostic testing or pharmacological intervention. For patients with diabetes mellitus, the overall benefits of exercise are clearly significant. Clinicians and patients must work together to maximize these benefits while minimizing risks for negative consequences. Identifying and preventing potential problems beforehand can reduce adverse outcomes and promote this important approach to healthy living.

Colorectal cancer screening participation: comparisons with mammography and prostate-specific antigen screening.

OBJECTIVES: The relation of personal characteristics, health and lifestyle behaviors, and cancer screening practices to current colorectal cancer (CRC) screening was assessed and compared with those factors' relation to current mammography screening in women and prostate-specific antigen (PSA) screening in men. METHODS: A cross-sectional random-digit-dialed telephone survey of 954 Massachusetts residents aged 50 and older was conducted. RESULTS: The overall prevalence of current CRC screening was 55.3%. Logistic regression results indicated that family history of CRC (odds ratio [OR] = 1.98; 95% confidence interval [CI] = 1.02, 3.86), receiving a regular medical checkup (OR = 3.07; 95% CI = 2.00, 4.71), current screening by mammography in women and PSA in men (OR = 4.40; 95% CI = 2.94, 6.58), and vitamin supplement use (OR = 1.87; 95% CI = 1.27, 2.77) were significant predictors of CRC screening. CONCLUSIONS: Health and lifestyle behaviors were related to increased current CRC, mammography, and PSA screening. Personal factors independently related to CRC screening were not consistent with those related to mammography and PSA screening. This lack of consistency may reflect different stages of adoption of each type of screening by clinicians and the public.

A prospective study of alcohol consumption and cataract extraction among U.S. women.

PURPOSE: Alcohol consumption has been implicated in the pathogenesis of cataract in some, but not all analytic studies. To date, no prospective analysis of the relationship between alcohol consumption and cataract has been conducted in women. METHODS: We examined the association between alcohol consumption and cataract extraction in a prospective cohort of female registered nurses. In 1980, 50,461 women were included and others were added as they became 45 years of age for a total of 77,466 women. Information on alcohol consumption and incidence of senile cataract extraction was ascertained during 12 years of follow-up with biennial questionnaires. RESULTS: We observed 1468 cases of cataract extraction in 761,036 person-years of follow-up. Compared to nondrinkers, those consuming alcohol were not at increased risk of cataract, even up to 25 grams or more per day (2 or more drinks). Results remained unchanged after controlling for cataract risk factors including cigarette smoking, body mass index, and diabetes. When risk was examined for specific cataract subtypes only, those in the highest category of consumption had a multivariate relative risk of 1.10 for nuclear cataracts and 1.50 for posterior subcapsular cataracts only. CONCLUSIONS: These prospective data suggest that there is no substantial overall increased risk of senile cataract due to alcohol intake. The possibility that alcohol consumption leads to a modest increased risk of posterior subcapsular type opacities requiring extraction merits further exploration.

Evaluation of a child sexual abuse prevention program.

A half-million children are believed to be sexually abused each year in the United States. In 1995, the American Medical Association declared sexual assault "a silent violent epidemic." The majority of efforts to stop child sexual abuse have focused on punishing abusers and treating victims and their families; prevention programs are uncommon and rely on educating children to report sexual abuse. This case study describes the evaluation of the first public health campaign designed to target adults for prevention. A baseline assessment of attitudes, awareness, knowledge, and policies was conducted in Vermont to identify facilitators and barriers to adult prevention of child sexual abuse. These included predisposing factors (50% of Vermont residents did not know the characteristics of an abuser), enabling factors (60% of Vermont residents did not know where to refer someone who may have sexual behavior problems), and reinforcing factors (when focus group participants knew an abuser, they were less likely to take action). This process guided the intervention, which included a broad-based media campaign targeting adults; a one-to-one communications strategy that provided information to agencies working with families at risk and a toll-free helpline for adults in an abuse situation; and a systems change strategy designed to educate decision-makers and leaders. Program evaluation measures included a random-digit dial survey, focus groups, a survey of Vermont decision-makers, and other data sets. The successes and limitations of these interventions, both as strategies in themselves and as data sources for evaluation, are discussed.

A prospective study of vitamin supplement intake and cataract extraction among U.S. women.

We prospectively examined the association between vitamin supplement intake and the incidence of cataract extraction during 12 years of follow-up in a cohort of 47,152 female nurses. Women were 45 years or older and free of diagnosed cancer in 1980; others were added as they reached 45 years of age, for a total of 73,956 women. During 720,082 years of follow-up, 1,377 senile cataracts were diagnosed and extracted. Those who used multivitamins or separate supplements of vitamin C, E, or A did not have decreased risks of cataract as compared with nonusers even for use of 10 or more years. After adjusting for cataract risk factors, including cigarette smoking, body mass index, and diabetes mellitus, users of vitamin C supplements for 10 or more years had a relative risk (RR) of 0.95 [95% confidence interval (CI) = 0.76-1.20]. Associations were stronger among long-term vitamin C supplement users who were never-smokers (RR = 0.71; 95% CI = 0.47-1.08) and less than 60 years of age (RR = 0.72; 95% CI = 0.49-1.04). These findings suggest that there is little overall benefit of long-term use of vitamin supplements for risk of cataracts requiring extraction.

A prospective study of carotenoid and vitamin A intakes and risk of cataract extraction in US women.

BACKGROUND: Oxidation of lens proteins plays a central role in the formation of age-related cataracts, suggesting that dietary antioxidants may play a role in prevention. However, the relation between specific antioxidants and risk of cataract remains uncertain. OBJECTIVE: Our objective was to examine prospectively the association between carotenoid and vitamin A intakes and cataract extraction in women. METHODS: A prospective cohort of registered female nurses aged 45-71 y and free of diagnosed cancer was followed; in 1980, 50461 were included and others were added as they became 45 y of age for a total of 77466. Information on nutrient intake was assessed by repeated administration of a food-frequency questionnaire during 12 y of follow-up. RESULTS: During 761762 person-years of follow-up, 1471 cataracts were extracted. After age, smoking, and other potential cataract risk factors were controlled for, those with the highest intake of lutein and zeaxanthin had a 22% decreased risk of cataract extraction compared with those in the lowest quintile (relative risk: 0.78; 95% CI: 0.63, 0.95; P for trend = 0.04). Other carotenoids (alpha-carotene, beta-carotene, lycopene, and beta-cryptoxanthin), vitamin A, and retinol were not associated with cataract in multivariate analysis. Increasing frequency of intakes of spinach and kale, foods rich in lutein, was associated with a moderate decrease in risk of cataract. CONCLUSIONS: Lutein and zeaxanthin and foods rich in these carotenoids may decrease the risk of cataracts severe enough to require extraction.

A prospective study of carotenoid intake and risk of cataract extraction in US men.

BACKGROUND: Dietary antioxidants, including carotenoids, are hypothesized to decrease the risk of age-related cataracts by preventing oxidation of proteins or lipids within the lens. However, prospective epidemiologic data concerning this phenomenon are limited. OBJECTIVE: Our objective was to examine prospectively the association between carotenoid and vitamin A intakes and cataract extraction in men. DESIGN: US male health professionals (n = 36644) who were 45-75 y of age in 1986 were included in this prospective cohort study. Others were subsequently included as they became 45 y of age. A detailed dietary questionnaire was used to assess intake of carotenoids and other nutrients. During 8 y of follow-up, 840 cases of senile cataract extraction were documented. RESULTS: We observed a modestly lower risk of cataract extraction in men with higher intakes of lutein and zeaxanthin but not of other carotenoids (alpha-carotene, beta-carotene, lycopene, and beta-cryptoxanthin) or vitamin A after other potential risk factors, including age and smoking, were controlled for. Men in the highest fifth of lutein and zeaxanthin intake had a 19% lower risk of cataract relative to men in the lowest fifth (relative risk: 0.81; 95% CI: 0.65, 1.01; P for trend = 0.03). Among specific foods high in carotenoids, broccoli and spinach were most consistently associated with a lower risk of cataract. CONCLUSIONS: Lutein and zeaxanthin may decrease the risk of cataracts severe enough to require extraction, although this relation appears modest in magnitude. The present findings add support for recommendations to consume vegetables and fruit high in carotenoids daily.

A prospective study of pregravid oral contraceptive use and risk of hypertensive disorders of pregnancy.

Oral contraceptive use is associated with hypertension, dyslipidemias, and insulin resistance, all of which also characterize hypertensive disorders of pregnancy. In this prospective cohort study, the association of oral contraceptive use before pregnancy and the risk of gestational hypertension and preeclampsia was assessed. Between 1991 and 1995, 3973 nulliparous women who reported their first pregnancy lasting > or = 6 months were studied. Pregravid exposures were collected by biennial mailed questionnaires, and cases were confirmed by medical record review. Recent oral contraceptive use was defined as use within 2 years of pregnancy. Proportional hazards analysis was used to adjust for potential confounding variables. During the 4 years of follow-up, 133 (3.3%) women with gestational hypertension and 62 (1.6%) with preeclampsia were identified. Twenty-five percent of women who did not develop these disorders were recent users of oral contraceptives, compared with 19% (p = 0.11) of women who developed gestational hypertension and 30% (p = 0.38) who developed preeclampsia. Mean duration of prior oral contraceptive use was similar for cases and noncases. Compared with never and past users, the multivariate relative risk among recent users for developing gestational hypertension was 0.7 (95% confidence interval (CI), 0.4-1.0) and for preeclampsia was 1.3 (95% CI, 0.8-2.4). Among recent users who had used oral contraceptives for > or = 8 years, the relative risk for gestational hypertension was 0.6 (95% CI, 0.3-1.2) and for preeclampsia was 2.1 (95% CI, 1.1-4.2). When the analysis was restricted to women who had never smoked, the risk for gestational hypertension was 0.2 (95% CI, 0.1-0.9) and for preeclampsia was 4.1 (95% CI, 1.9-8.7). Thus, recent use of oral contraceptives was associated with a reduced risk for developing gestational hypertension. In contrast, there was a suggestion that recent use was associated with an increased risk of developing preeclampsia, but only among women who had used these agents for > or = 8 years.

PIP: This article presents a prospective study on the relationship between pregravid oral contraceptive use and the risk of pregnancy-related hypertensive disorders. Oral contraceptives have been known to increase the risk to hypertension, dyslipidemias and insulin resistance, which characterize hypertensive disorders of pregnancy. This study examines this presumption by employing 3973 nulliparous women with pregnancies lasting 6 months during 1991-95. Data were taken from the results of biennial questionnaires and examination of prenatal records. Follow-up for the past 4 years identified 133 (3.3%) women with gestational hypertension and 62 (1.6%) with preeclampsia. Recent oral contraceptive use within 2 years of pregnancy was inversely associated with the development of gestational hypertension but was directly associated with preeclampsia. Compared with never users and past users, multivariate relative risk among recent users for the development of gestational hypertension was 0.7 (95% CI, 0.4-1.0) and of preeclampsia was 1.3 (95% CI, 0.8-2.4). Recent use of oral contraceptives (8 or more years) predisposes to a 0.6 risk for gestational hypertension and a 2.1 risk for preeclampsia. Thus, recent use of oral contraceptives was associated with a reduced risk for developing gestational hypertension. In contrast, there was a suggestion that recent use was associated with an increased risk of developing pre-eclampsia, but only among women who had used these agents for 8 or more years.

Epidemiology of oral contraceptives and cardiovascular disease.

PURPOSE: To review the association between combined oral contraceptives and cardiovascular disease, with emphasis on oral contraceptives containing low doses of estrogen (low-dose oral contraceptives). DATA SOURCES: A systematic search of the MEDLINE database was done for all relevant articles published between 1967 (when low-dose oral contraceptives were introduced in the United States) and June 1997. Textbooks, meeting proceedings, and reference lists were also searched. STUDY SELECTION: All English-language human epidemiology studies of oral contraceptives that used cardiovascular disease as an end point were reviewed. Animal and metabolic studies were reviewed only if they were especially relevant to the mechanism of action of oral contraceptives. DATA EXTRACTION: Descriptive and analytic data from each study were collected. DATA SYNTHESIS: Data were organized by cardiovascular end point, study design, estrogen dose, and type of progestogen. Data on relative and absolute risk are presented to address current prescription guidelines. CONCLUSIONS: The risk for cardiovascular disease is lower with current preparations of oral contraceptives, including those that contain the new progestogens, than with older oral contraceptives containing high doses of estrogen. Among users of low-dose oral contraceptives, cardiovascular diseases occur mainly in smokers and women with predisposing factors. Every effort should be made to encourage smoking cessation among potential users of oral contraceptives.

PIP: The cardiovascular risk associated with use of combined oral contraceptives (OCs) was assessed through a review of the English-language literature published from 1967 (when low-dose OCs were introduced in the US) and June 1997. Data were organized by cardiovascular end point (myocardial infarction, stroke, venous thrombosis and pulmonary embolism), study design, estrogen dose, and type of progestogen. As a result of the rarity of cardiovascular disease in young women, few such events are available for analysis, even in large cohorts of women. However, the review suggested that the overall risk for cardiovascular disease is substantially lower with current OC preparations containing 50 mcg of estrogen or less, including those that contain the new progestogens, than with older OCs containing high doses of estrogen. Preliminary case-control studies indicate that the risk of myocardial infarction is lower among users of OCs containing desogestrel and gestodene while that of venous thromboembolism may be elevated with these progestogens compared with levonorgestrel. Of concern is emerging evidence that the newer OCs have an attenuated acute prothrombotic reaction with cigarette smoking compared to older formulations. For stroke as well, OC users who smoke are substantially more susceptible than nonsmoking users. Every effort should be made to encourage smoking cessation among potential or current users of OCs.

Oral contraceptives and ovulatory causes of delayed fertility.

The return of fertility for women who discontinue oral contraceptives takes longer as compared with women who discontinue other methods of contraception. It remains unclear, however, whether subsequent fertility differs according to duration or age at first use. The authors performed a nested case-control study within a cohort of 116,686 female registered nurses residing in 14 US states. Baseline information was reported on mailed questionnaires in 1989. Cases comprised 1,917 married nurses without previous pregnancy who were unable to become pregnant for at least 1 year and were subsequently diagnosed with primary ovulatory infertility. Controls comprised 44,521 married parous nurses with no history of infertility and no pregnancies lasting less than 6 months. After allowing for 2 years of suppressed fertility following discontinuation of oral contraceptive use and excluding women with signs of menstrual or hormonal disorder, the authors found that the multivariate relative risk for ovulatory causes of delayed fertility was 1.2 (95% confidence interval 0.7-1.9) for ever users. There was no statistically significant trend of increasing risk with increasing duration of use and younger age at first use. The fact that 88 percent of cases reported an eventual pregnancy by 1993 suggests that absolute fertility was not impaired.

A prospective study of oral contraceptives and NIDDM among U.S. women.

OBJECTIVE: To examine prospectively the association between modern oral contraceptives with low doses of estrogen and progestin and subsequent incidence of NIDDM. RESEARCH DESIGN AND METHODS: In a prospective cohort study, 98,590 U.S. female nurses aged 25 to 42 and free of diagnosed diabetes, coronary heart disease, stroke, and cancer at baseline in 1989 were followed for 4 years. Endpoint was incidence of confirmed NIDDM. Oral contraceptive use was reported on mailed questionnaires. RESULTS: During 352,067 person-years follow-up, we confirmed 185 incident cases of NIDDM. After adjusting for age, BMI, cigarette smoking, family history of diabetes, parity, physical activity, alcohol intake, ethnicity, history of diagnosis of infertility, elevated cholesterol, and hypertension, women currently using oral contraceptives had a relative risk (RR) of 1.6 (95% CI, 0.9-3.1). For past users, the multivariate RR was 1.2 (95% CI, 0.8-1.8). This association was attenuated after restricting the analysis to symptomatic cases of NIDDM. For current users, RR = 1.3 (95% CI, 0.6-2.8), and for past users, RR = 0.9 (95% CI, 0.6-1.4), suggesting that increased surveillance may explain at least part of any excess risk. CONCLUSIONS: In this large prospective study, we found no appreciable increase in the 4-year risk of NIDDM among current users of oral contraceptives. There was no apparent increase in risk among past users. The small number of cases reflect the low absolute risk of NIDDM in this population of young women.

Reproducibility of oral contraceptive histories and validity of hormone composition reported in a cohort of US women.

Histories of oral contraceptive (OC) use were reported by 116,686 women aged 25 to 42 years in the Nurses' Health Study II on a self-administered questionnaire accompanied by a color photo booklet of all OC preparations ever marketed in the US. To evaluate the quality of this information, we compared the responses of a randomly selected sample of 215 participants with their data from a subsequent, detailed telephone interview using a structured life events calendar. Agreement for a history of ever having used OC was high between the two methods (exact agreement 99%). Reported durations of use were equivalent (mean duration 42.7 months by telephone interview and 44.6 months by questionnaire). The Spearman correlation for duration of use calculated from the two methods was 0.94 (p < 0.0001). For a subset of women for whom we were able to obtain OC prescription records, the medical record confirmed the use of an identical or equivalent brand in 75% of intervals of reported use. Acceptably valid OC histories were obtained with a self-administered questionnaire.

PIP: Recall bias is a major concern in case-control studies of the association between oral contraceptives (OCs) and conditions such as breast cancer or thromboembolism. Studies of the validity of OC use histories have been limited, however, by the difficulty of obtaining reference information. The 116,686 US women 25-42 years of age enrolled in the self-administered Nurses' Health Study II were provided color photographs of all OCs ever marketed in the US for reference in providing their OC use histories. The quality of these responses was evaluated in telephone interviews conducted 6-14 months later with a randomly selected sample of 215 of these women who completed a structured reproductive life events calendar. There was 99% agreement between these two reporting methods for history of OC ever-use. Of 38 women who reported never using OCs in the telephone interview, only 1 had reported such use on the questionnaire. Reported durations of OC use also were equivalent (mean duration, 42.7 months by telephone interview and 44.6 months by questionnaire). In the subset of 150 women for whom OC prescription records were available, the medical record confirmed use of an identical or equivalent OC brand as identified in the questionnaire in 75% of intervals of reported use. Most disagreements were due to minor differences in dose; 90% matched on category of estrogen type and 74% matched on progestin type. These findings suggest that valid OC histories can be obtained through self-administered questionnaires and that the small amount of misclassification that occurs should not obscure important associations with disease.

Prospective study of oral contraceptives and hypertension among women in the United States.

BACKGROUND: Oral contraceptives induce hypertension in approximately 5% of users of high-dose pills that contain at least 50 micrograms estrogen and 1 to 4 mg progestin, and small increases in blood pressure have been reported even among users of modern low-dose formulations. However, neither the responsible hormone in the oral contraceptive nor particular subgroups of women who might be susceptible to the hypertensive effect of oral contraceptives have been identified. METHODS AND RESULTS: In a prospective cohort study in the United States, 68 297 female nurses aged 25 to 42 years and free of diagnosed hypertension, diabetes, coronary heart disease, stroke, and cancer at baseline were followed up for 4 years. During 231 006 person-years of follow-up, 1567 incident cases of hypertension were diagnosed. Compared with women who had never used oral contraceptives, the age-adjusted relative risk was 1.5 (95% CI = 1.2 to 1.8) for current use and 1.1 (95% CI = 0.9 to 1.2) for past use. After adjustment for age, body mass index, hormones cigarette smoking, family history of hypertension, parity, physical activity, alcohol intake, and ethnicity, current users of oral contraceptives had an increased risk of development of hypertension (RR = 1.8; 95% CI = 1.5 to 2.3) compared with women who had never used them. The multivariate relative risk for past users was 1.2 (95% CI = 1.0 to 1.4). There were no important modifying effects of age, family history of hypertension, ethnicity, or body mass index. CONCLUSIONS: Current users of oral contraceptives had a significant, moderately increased risk of hypertension. However, among this group, only 41.5 cases per 10 000 person-years could be attributed to oral contraceptive use. Risk decreased quickly with cessation of oral contraceptives, and past users appeared to have only a slightly increased risk.