Myocardial infarction and the use of estrogen and estrogen-progestogen in postmenopausal women

OBJECTIVE

To estimate the relative risk for incident acute myocardial infarction in relation to the current use of estrogen and estrogen-progestogen.

DESIGN

Retrospective case-control study.

SETTING

Medical centers of a large prepaid health care program, the Kaiser Permanente Medical Care Program (KPMCP), Northern California region.

PARTICIPANTS

All women hospitalized at a KPMCP center for incident acute myocardial infarction during a 3-year period from 1991 to 1994. Controls were matched to case-patients for year of birth and KPMCP facility and were selected at random from among all female members of the KPMCP.

INTERVENTION

An in-person interview that included questions about current and lifetime use of estrogen and estrogen-progestogen; known cardiovascular risk factors; and other medical, sociodemographic and behavioral factors that might affect risk for myocardial infarction.

MAIN OUTCOMES MEASURE

Odds ratios for myocardial infarction associated with use of estrogen and estrogen-progestogen.

RESULTS

The odds ratio for myocardial infarction in current users of estrogen or estrogen-progestogen compared with women who had never used these agents was 0.96 (95% CI, 0.66 to 1.40) after adjustment for confounders. The odds ratio for myocardial infarction in past users of estrogen or estrogen-progestogen was 1.07 (CI, 0.72 to 1.58). Duration of hormone use was unrelated to the odds ratio for myocardial infarction.

CONCLUSIONS

This study did not show a statistically significant decrease in the odds ratio for myocardial infarction associated with current use of estrogen or estrogen-progestogen. It neither confirms nor refutes the hypothesis that hormone use prevents myocardial infarction in postmenopausal women.

Reduced cholesterol is associated with recent minor illness: the CARDIA Study. Coronary Artery Risk Development in Young Adults

Lower levels of plasma total cholesterol have been observed during severe infection, but it is not known whether the minor illnesses encountered in the general population are also associated with reduced cholesterol. This paper examines the relation between minor illness and plasma lipids, using 7- and 10-year follow-up data from more than 3,000 generally healthy participants in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. At both 7 and 10 years, approximately 8.5% of participants stated they had been "ill with cold, flu, fever, or vomiting in the past 24 hours." In both cross-sectional and longitudinal analyses, the plasma total cholesterol was about 5 mg/dl lower (p < 0.006) and high density lipoprotein cholesterol about 1.2 mg/dl lower (p < 0.12) in those who reported minor illness than in those who did not. Plasma triglycerides did not vary with minor illness. The authors conclude that reductions in plasma total, low density, and high density lipoprotein cholesterol mark an acute phase response even during minor illness. These reductions may bias surveys over a limited geographic area during a short period because the proportion with minor illness may vary locally. Because this effect should be stronger with more precise illness diagnosis, clinicians should avoid making measurements for cholesterol management when illness may alter plasma lipid levels and the resulting decisions.

Marijuana use and cancer incidence (California, United States)

The purpose of this retrospective cohort study was to examine the relationship of marijuana use to cancer incidence. The study population consisted of 64,855 examinees in the Kaiser Permanente multiphasic health checkup in San Francisco and Oakland (California, United States), between 1979-85, aged 15 to 49 years, who completed self-administered questionnaires about smoking habits, including marijuana use. Follow-up for cancer incidence was conducted through 1993 (mean length 8.6 years). Compared with nonusers/experimenters (lifetime use of less than seven times), ever- and current use of marijuana were not associated with increased risk of cancer of all sites (relative risk [RR] = 0.9, 95 percent confidence interval [CI] = 0.7-12 for ever-use in men; RR = 1.0, CI = 0.8-1.1 in women) in analyses adjusted for sociodemographic factors, cigarette smoking, and alcohol use. Marijuana use also was not associated with tobacco-related cancers or with cancer of the following sites: colorectal, lung, melanoma, prostate, breast, cervix. Among nonsmokers of tobacco cigarettes, ever having used marijuana was associated with increased risk of prostate cancer (RR = 3.1, CI = 1.0-9.5) and nearly significantly increased risk of cervical cancer (RR = 1.4, CI = 1.0-2.1). We conclude that, in this relatively young study cohort, marijuana use and cancer were not associated in overall analyses, but that associations in nonsmokers of tobacco cigarettes suggested that marijuana use might affect certain site-specific cancer risks.

Epidemiology of low total plasma cholesterol concentration among young adults: the CARDIA study. Coronary Artery Risk Development in Young Adults

BACKGROUND

Data on stability of plasma total cholesterol levels and its determinants among young adults are lacking. Knowledge of factors associated with low levels of plasma total cholesterol during young adulthood may help clarify the nature of associations between hypocholesterolemia and health or illness.

METHODS

Tracking of plasma total cholesterol was investigated using data from the baseline (1985-1986), Year 5 (1990-1991), and Year 7 (1992-1993) examinations of the Coronary Artery Risk Development in Young Adults Study. Lifestyle (including dietary), physiological, medical, and psychological correlates of plasma total cholesterol were examined cross-sectionally at baseline using ANCOVA and multivariate logistic regression. The attributes of participants with persistently low plasma total cholesterol level after 7 years (i.e., remaining below the 10th percentile of sex- and race-specific distributions) were also examined.

RESULTS

The cohort in this analysis comprised 720 black men, 922 white men, 899 black women, and 944 white women who were between the ages of 18 and 30 years at baseline. Between 44 and 52% of those with plasma total cholesterol levels below the 10th percentile remained below the same percentile 7 years later. Among black men, a difference of 1 SD in age [3.7 years; odds ratio (OR) = 0.69; 95% CI = 0.52-0.91] and a difference of 1 SD in systolic blood pressure (10.5 mm Hg; OR = 0.73; 95% CI = 0.54-0.97) were independently associated with lower odds, respectively, of being in the lowest 10th percentile of the plasma total cholesterol distribution. Also among black men, current smoking and more calories from carbohydrates were associated with nonsignificantly higher odds of low total cholesterol level. Among white men, a 1 SD older age (3.4 years; OR = 0.78; 95% CI = 0.61-1.00) and a 1 SD higher physical fitness (118 sec; OR = 1.41; 95% CI = 1.09-1.82) predicted lower and higher odds, respectively, of low plasma total cholesterol. Among black women, a 1 SD difference in albumin (0.3 g/dL; OR = 0.80; 95% CI = 0.63-1.03) was related to lower odds of low plasma total cholesterol. Among white women, the factors independently associated with low plasma total cholesterol were body mass index (OR for a difference in 4.0 kg/m2 = 0.73; 95% CI = 0.54-1.00) and gamma-glutamyl transferase (OR for an increase in 9.6 IU/L = 0.41; 95% CI = 0.18-0.93). The independent predictive factors of stably low total cholesterol levels were age and uric acid among black men (both inversely related) and age, Framingham Type A Behavior (inversely), and calories from carbohydrates (positively related) among white men.

CONCLUSION

Young adults with low plasma total cholesterol level have characteristics generally associated with good cardiovascular health. However, adverse attributes such as current cigarette smoking (notably among black men) may confound future associations between low total cholesterol and disease.

The safety of transurethral prostatectomy: a cohort study of mortality in 9,416 men

PURPOSE

We assessed the mortality rate from transurethral resection of the prostate.

MATERIALS AND METHODS

From 1976 to 1984, 4,708 patients undergoing transurethral resection of the prostate for benign prostatic hypertrophy (BPH) were compared retrospectively to an age-matched group of 4,708 randomly selected Kaiser Permanente Medical Care Program members not undergoing surgery. The risk of mortality associated with transurethral resection of the prostate relative to no surgery was determined using proportional hazards models.

RESULTS

The relative risk for surgery versus no surgery for the total group was 0.88 (95% confidence interval 0.82 to 0.95). Similarly, the results for each 5-year age group demonstrated a relative risk of 0.77 to 0.95.

CONCLUSIONS

This cohort study showed no excess mortality for patients undergoing transurethral resection of the prostate compared to age-matched comparison subjects randomly selected from health plan members who did not undergo surgery. Information from this study about the safety of transurethral resection of the prostate can be shared with patients when discussing treatment options.

Risk factors for hip fracture in men. Hip Fracture Study Group

To identify risk factors for hip fracture in men, the authors conducted a case-control study involving 20 hospitals in Philadelphia, Pennsylvania, and 14 hospitals in Kaiser Permanente Medical Care Program of northern California. The 356 enrolled men had been admitted with a radiologically confirmed first hip fracture. The 402 control men either were from the Philadelphia area or were members of Kaiser Permanente and were frequency matched to the cases by age and ZIP code or telephone exchange. Information on potential risk factors was obtained through personal interviews. Men in the lowest quintile of body mass had a greatly increased risk of hip fracture compared with men in the heaviest quintile (odds ratio (OR) 3.8, 95% confidence interval (CI) 2.3-6.4). Premorbid lower limb dysfunction was associated with increased risks for hip fracture (OR 3.4, 95% CI 2.1-5.4). Increased risks were also observed with the use of cimetidine (OR 2.5, 95% CI 1.4-4.6) and psychotropic drugs (OR 2.2, 95% CI 1.4-3.3). Smoking cigarettes or a pipe increased the risk of hip fracture, and this association was independent of body mass. Finally, previous physical activity was markedly protective. Factors thought to affect bone density as well as factors identified as risk factors for falls appear to be important determinants of the risk of hip fracture in men. Physical activity may be a particularly promising preventive measure for men. Additional studies of the use of cimetidine on osteoporosis and osteoporotic fractures are indicated.

Lifetime cocaine use and cardiovascular characteristics among young adults: the CARDIA study

OBJECTIVES

Cocaine is a central nervous system stimulant associated with cardiovascular disease risk factors, morbidity, and mortality. Despite these demonstrated relationships, it has been difficult to assess the long-term cardiovascular consequences of cocaine use.

METHODS

The Coronary Artery Risk Development in Young Adults study provides an opportunity to evaluate the association of lifetime cocaine use with cardiovascular disease risk factors in a randomly sampled biethnic cohort of men and women of varied socioeconomic status, aged 20 to 32 in 1987.

RESULTS

More extensive cocaine use experience was associated with being White, older, and less educated, regardless of sex. Higher levels of licit and illicit substance use behavior were reported by those reporting more extensive cocaine experience; however, most cardiovascular disease risk factors such as systolic and diastolic blood pressure, heart rate, hypertension, physical activity, and anthropometric measurements were not related to lifetime cocaine experience.

CONCLUSIONS

In this age group, the detrimental cardiovascular effects of cocaine may be limited to acute effects. Further studies are needed to determine whether continued exposure is related to cardiovascular disease risk factors later in life.

Marijuana use and mortality

OBJECTIVES

The purpose of this study was to examine the relationship of marijuana use to mortality.

METHODS

The study population comprised 65171 Kaiser Permanente Medical Care Program enrollees, aged 15 through 49 years, who completed questionnaires about smoking habits, including marijuana use, between 1979 and 1985. Mortality follow-up was conducted through 1991.

RESULTS

Compared with nonuse or experimentation (lifetime use six or fewer times), current marijuana use was not associated with a significantly increased risk of non-acquired immunodeficiency syndrome (AIDS) mortality in men (relative risk [RR] = 1.12, 95% confidence interval [CI] = 0.89, 1.39) or of total mortality in women (RR = 1.09, 95% CI = 0.80, 1.48). Current marijuana use was associated with increased risk of AIDS mortality in men (RR = 1.90, 95% CI = 1.33, 2.73), an association that probably was not causal but most likely represented uncontrolled confounding by male homosexual behavior. This interpretation was supported by the lack of association of marijuana use with AIDS mortality in men from a Kaiser Permanente AIDS database. Relative risks for ever use of marijuana were similar.

CONCLUSIONS

Marijuana use in a prepaid health care-based study cohort had little effect on non-AIDS mortality in men and on total mortality in women.

Racial differences in bone density between young adult black and white subjects persist after adjustment for anthropometric, lifestyle, and biochemical differences

This study tested whether racial differences in bone density can be explained by differences in bone metabolism and lifestyle. A cohort of 402 black and white men and women, ages 25-36 yr, was studied at the Kaiser Permanente Medical Care Program in Northern California, a prepaid health plan. Body composition (fat, lean, and bone mineral density) was measured using a Hologic-2000 dual-energy x-ray densitometer. Muscle strength, blood and urine chemistry values related to calcium metabolism, bone turnover, growth factors, and level of sex and adrenal hormones were also measured. Medical history, physical activity, and lifestyle were assessed. Statistical analyses using t- and chi-square tests and multiple regression were done to determine whether racial difference in bone density remained after adjustment for covariates. Bone density at all skeletal sites was statistically significantly greater in black than in white subjects; on average, adjustment for covariates reduced the percentage density differences by 42% for men and 34% for women. Adjusted bone density at various skeletal sites was 4.5-16.1% higher for black than for white men and was 1.2-7.3% higher for black than for white women. We concluded that racial differences in bone mineral density are not accounted for by clinical or biochemical variables measured in early adulthood.

Incidence of stroke and myocardial infarction in women of reproductive age

BACKGROUND AND PURPOSE

Information on the incidence of vascular disease in women of reproductive age has been limited. These disease are rare in this age group, and a large population base is required for reliable estimation of incidence.

METHODS

For a case-control study of vascular disease and low-dose oral contraceptive use, we used emergency department logs and hospital admission and discharge records to ascertain fatal and nonfatal cases of first-ever stroke and myocardial infarction (MI) in women 15 to 44 years of age who were-members of a large California HMO. Incidence rates of stroke and MI were calculated on the basis of these data.

RESULTS

The incidence of MI not associated with pregnancy was 5.0 per 100,000 women-years. The incidence of stroke not associated with pregnancy was 10.7 per 100,000 women-years. MI was very rare until age 35 years. At every age, about half of hemorrhagic strokes were due to subarachnoid hemorrhage.

CONCLUSIONS

The incidence rates of stroke and MI are low in women of reproductive age in the United States.

Prevalence and health implications of anti-gay discrimination: a study of black and white women and men in the CARDIA cohort. Coronary Artery Risk Development in Young Adults

This study investigates the prevalence of self-reported experiences of discrimination based on sexual orientation among black and white women and men (25 to 37 years old) who are members of CARDIA, a multisite longitudinal study of cardiovascular risk factors. Among the 1,724 participants who responded to a 1989 questionnaire obtaining data on lifetime number of sexual partners and who participated in the Year 7 exam (1992-1993), which included questions about discrimination, 204 (12 percent) reported having at least one same-sex sexual partner: 27 (7 percent) of the 412 black women, 13 (6 percent) of the 221 black men, 87 (14 percent) of the 619 white women, and 77 (16 percent) of the 472 white men. Among these four groups, 33, 39, 52, and 56 percent, respectively, reported having experience discrimination based on sexual orientation. Additionally, 85 percent of black women and 77 percent of the black men reported having experienced racial discrimination, and 89 percent of the black women and 88 percent of the white women reported having experience gender discrimination. In the light of research associating negative stressors with poor health outcomes, including elevated blood pressure, future studies should assess public health implications of discrimination based on sexual orientation, in conjunction with racial and gender discrimination.

Myocardial infarction in users of low-dose oral contraceptives

OBJECTIVE

To determine the relationship between the use of low-dose (less than 50 micrograms estrogen) oral contraceptives (OC) and myocardial infarction.

METHODS

In this population-based case-control study, all incident myocardial infarctions in women, ages 15-44 years who were members of the Kaiser Permanente Medical Care Program, Northern and Southern California regions were ascertained during a 39-month period from 1991 through 1994. For each woman with myocardial infarction, up to three age- and facility-matched controls were chosen at random from female members. Information about OC use (predominantly low-dose preparations) was obtained in face-to-face interviews.

RESULTS

There were 187 incident cases of myocardial infarction during 3.6 million woman-years of observation (incidence rate, 5.2 per 100,000 woman-years). The prevalence of several risk factors for myocardial infarction was lower in controls who were current users of OCs than in controls who were noncurrent (past and never) users. The odds ratio for myocardial infarction in current OC users compared with noncurrent users was 1.65 (95% confidence interval 0.45, 6.06) after adjustment for major risk factors and for race and ethnicity, corresponding to an excess risk of less than one case per 100,000 woman-years. The study had 80% power to detect a relative risk of 2.3 (one-sided test, alpha = .05). The odds ratio of myocardial infarction in past OC users was not elevated.

CONCLUSION

With respect to myocardial infarction, low-dose oral contraceptives can be used safely by women who lack risk factors for coronary heart disease.

Differences in weight gain in relation to race, gender, age and education in young adults: the CARDIA Study. Coronary Artery Risk Development in Young Adults

OBJECTIVE

To assess ethnic differences in weight gain in young adults.

DESIGN

Five-year weight change was assessed in 4207 young adults initially aged 18-30 years at the CARDIA Study baseline examination (1985-1986).

RESULTS

Weight gain was significantly (p < 0.0001) greater in black versus white men (13.2 versus 9.1 lb) and in black versus white women (13.2 versus 7.4 lb). Baseline weight and year-five weight in all race and gender groups were strongly associated, suggesting a high degree of tracking of adiposity during young adulthood. Greater weight gain was noted in participants reporting baseline education of high school or less versus college graduates in black women (14.4 versus 10.0 lb, p < 0.05), white women (10.2 versus 5.2 lb, p < 0.0001) and white men (10.2 versus 7.8 lb, p < 0.001). Significantly greater weight gain was observed in younger (18-24 years) versus older (25-30 years) men, but no age-related difference was seen in women. The racial differences in weight gain remained after adjustment for age and level of education. The above trends were confirmed for other measures of body size, i.e. body mass index and skinfold thickness.

CONCLUSION

These data indicate that young adults are at high risk of weight gain, and that weight gain was greatest among African Americans and among less educated participants. These high-risk groups can be identified and targeted for primary prevention of adult obesity in addition to population wide efforts that will be required to counteract the secular trend of increased obesity observed in US adults.

Cocaine use and characteristics of young adult users from 1987 to 1992: the CARDIA Study. Coronary Artery Risk Development in Young Adults

OBJECTIVES

This study examined the relationship of sociodemographic factors and use of substances other than cocaine to cocaine use from 1987 to 1992 in a cohort of Black and White men and women 20 to 32 years of age.

METHODS

Data were collected as part of the Coronary Artery Risk Development in Young Adults study. Self-reported cocaine use was analyzed through chi-square tests and repeated measures analyses of variance to determine the bivariate and multivariate relationships of sociodemographics and substance use behaviors to cocaine use over the 5-year period.

RESULTS

Cocaine use declined in Whites but remained stable in Blacks from 1987 to 1992. Cross-sectional results showed that use was related to being Black, male and in the older half of the cohort, single, and unemployed; it was also related to higher levels of other substance use in 1987 and 1992. Over time, the magnitude and strength of the relationship were consistent for each variable except for increased odds of cocaine use among the unemployed and Blacks in 1992.

CONCLUSIONS

Sociodemographic characteristics and substance use behavior consistently identify individuals at risk for cocaine use. As a result, intervention programs should be targeted at these high-risk groups.

Low total serum cholesterol and intracerebral hemorrhagic stroke: is the association confined to elderly men? The Kaiser Permanente Medical Care Program

BACKGROUND AND PURPOSE

Epidemiological studies indicate a higher incidence of intracerebral (but not subarachnoid) hemorrhagic stroke among persons with low total serum cholesterol levels. This report further examines the prospective relationship of total serum cholesterol with subsequent intracerebral hemorrhage in a large, well-defined population.

METHODS

The cohort included 61756 enrollees in a health plan from the San Francisco-Oakland metropolitan area (46% men, 63% white), aged 40 to 89 years and free of cardiovascular disease at baseline. Sixteen-year incidence of combined nonfatal and fatal intracerebral hemorrhagic stroke (International Classification of Diseases [ICD], 8th revision, code 431, or ICD, 9th revision, codes 431 and 432) was investigated in relation to serum cholesterol measured in multiphasic health checkups made in 1977 through 1985. Intracerebral hemorrhagic events were ascertained using hospital discharge records and as underlying cause of death by the California Mortality Linkage Information System.

RESULTS

From 1978 through 1993 (average of 10.7 years), there were 386 events (201 in men, 29% fatal; 185 in women, 42% fatal). By multivariate proportional hazards life-table regression analysis, serum cholesterol level below the sex-specific 10th percentile (< 4.62 mmol/L [178 mg/dL] in men), compared with higher cholesterol level, was associated with a significantly increased risk of intracerebral hemorrhage in men aged 65 years or older (relative risk, 2.7; 95% confidence interval, 1.4 to 5.0). An excess risk was also observed among elderly women at the lowest cholesterol range, but a chance finding could not be ruled out. No relationship was seen among men or women aged 40 to 64, and no statistical interaction of low serum cholesterol with hypertension was found in either sex.

CONCLUSIONS

In these data, the association between low serum cholesterol level and intracerebral hemorrhage was confined to elderly men.

Racial discrimination and blood pressure: the CARDIA Study of young black and white adults

OBJECTIVES

This study examined associations between blood pressure and self reported experiences of racial discrimination and responses to unfair treatment.

METHODS

Survey data were collected in year 7 (1992/93) of the Coronary Artery Risk Development in Young Adults (CARDIA) study, a prospective multisite community-based investigation. Participants included 831 Black men, 1143 Black women, 1006 White men, and 1106 White women 25 to 37 years old.

RESULTS

Systolic blood pressure among working-class Black adults reporting that they typically accepted unfair treatment and had experienced racial discrimination in none of seven situations was about 7 mm Hg higher than among those reporting that they challenged unfair treatment and experienced racial discrimination in one or two of the situations. Among professional Black adults, systolic blood pressure was 9 to 10 mm Hg lower among those reporting that they typically challenged unfair treatment and had not experienced racial discrimination. Black-White differences in blood pressure were substantially reduced by taking into account reported experiences of racial discrimination and responses to unfair treatment.

CONCLUSIONS

Research on racial/ ethnic distributions of blood pressure should take into account how discrimination may harm health.

Relationship of lipoproteins, apolipoproteins, triglycerides and lipid ratios to plasma total cholesterol in young adults: the CARDIA Study. Coronary Artery Risk Development in Young Adults

OBJECTIVE

To characterize the association of carrier lipoproteins, apolipoproteins, triglycerides and various lipid ratios with total cholesterol in young adults.

DESIGN

Cross-sectional data from the baseline examination (1985-1986) of The Coronary Artery Risk Development In Young Adults (CARDIA) Study, a multicenter investigation of a biracial cohort of 4941 men and women aged 18-30 years.

METHODS

Multiple linear regression models to estimate mean levels of lipids and lipoproteins for each category of total cholesterol, stratified by race and sex and adjusted for age and education level.

RESULTS

As expected, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), apolipoprotein B (ApoB), apolipoprotein A-1 (ApoA-1) and triglycerides increased linearly with the level of total cholesterol in all race-sex subgroups. The LDL-C/HDL-C, ApoB/ApoA-1 and LDL-C/ApoB ratio also increased with total cholesterol in all race-sex subgroups. The HDL-C/ApoA-1 ratio, indicative of cholesterol content per HDL particle, did not vary with total cholesterol except in white men, in whom it was slightly lower for those with high total cholesterol than those with low total cholesterol concentrations. White men showed higher triglyceride concentrations and lower HDL-C for any given total cholesterol strata. All these associations of lipoproteins, apolipoproteins and lipid ratios with total cholesterol were independent of body mass index, smoking status, fitness level and Keys score.

CONCLUSIONS

Young adults with low total cholesterol have lipoprotein profiles characterized by low atherogenic potential. White men with high total cholesterol levels, compared with other groups, showed a lipid profile more conductive to atherogenesis.

Adverse effect of pregnancy on high density lipoprotein (HDL) cholesterol in young adult women. The CARDIA Study. Coronary Artery Risk Development in Young Adults

The authors analyzed data from the Coronary Artery Risk Development in Young Adults (CARDIA) Study in order to examine associations between parity and lipoproteins. Of 2,787 women recruited in 1985-1986, 2,534 (91%) returned in 1987-1988 and 2,393 (86%) returned in 1990-1991 for repeat evaluations. Two-year change (1987-1988 to 1985-1986) in high density lipoprotein (HDL) cholesterol was significantly different among the parity groups. HDL cholesterol decreased in women who had their first pregnancy of at least 28 weeks duration during follow-up (mean +/- standard error, -3.5 +/- 1.2 mg/dl), and this change was significantly different from the increase in women parous at baseline who had no further pregnancies (2.5 +/- 0.3 mg/dl) and in nullipara (2.4 +/- 0.3 mg/dl). There was a nonsignificant trend for a greater decrease in HDL2 cholesterol fraction in the primipara compared with the other groups. The HDL cholesterol decrease remained significant after controlling for race, age, education, oral contraceptive use, and changes in body mass index, waist-hip ratio, physical activity, smoking status, and alcohol intake. Change in HDL cholesterol was also significantly different among the parity groups in analyses of pregnancies that occurred during the subsequent 3 years of follow-up. There were no differences for change in LDL cholesterol or triglycerides. Potential mechanisms for a detrimental effect of pregnancy on HDL cholesterol include hormonal, body composition, or life-style/behavioral changes.

Stroke in users of low-dose oral contraceptives

BACKGROUND

Previous studies have linked the use of oral contraceptive agents to an increased risk of stroke, but those studies have been limited to oral contraceptives containing more estrogen than is now generally used.

METHODS

In a population-based, case-control study, we identified fatal and nonfatal strokes in female members of the California Kaiser Permanente Medical Care Program and who were 15 through 44 years of age. Matched controls were randomly selected from female members who had not had strokes. Information about the use of oral contraceptives (essentially limited to low-estrogen preparations) was obtained in interviews.

RESULTS

A total of 408 confirmed strokes occurred in a total of 1.1 million women during 3.6 million woman-years of observation. The incidence of stroke was thus 11.3 per 100,000 woman-years. On the basis of data from 295 women with stroke who were interviewed and their controls, the odds ratio for ischemic stroke among current users of oral contraceptives, as compared with former users and women who had never used such drugs, was 1.18 (95 percent confidence interval, 0.54 to 2.59) after adjustment for other risk factors for stroke. The adjusted odds ratio for hemorrhagic stroke was 1.14 (95 percent confidence interval, 0.60 to 2.16). With respect to the risk of hemorrhagic stroke, there was a positive interaction between the current use of oral contraceptives and smoking (odds ratio for women with both these factors, 3.64; 95 percent confidence interval, 0.95 to 13.87).

CONCLUSIONS

Stroke is rare among women of childbearing age. Low-estrogen oral-contraceptive preparations do not appear to increase the risk of stroke.

Television viewing and cardiovascular risk factors in young adults: the CARDIA study

Cross-sectional associations between self-reported hours of television (TV) viewing per day and cardiovascular risk factors were assessed in a biracial (black and white) study population of 4280 men and women, ages 23 to 35 years, undergoing the year-5 follow-up examination for the Cardiovascular Risk Development in Young Adults (CARDIA) study in 1990 to 1991. Number of hours of TV viewing per day was higher in blacks than in whites and was inversely associated with education and income. Relative to "light" TV viewers (0 to 1 h/d), "heavy" TV viewers (> or = 4 h/d) had a higher prevalence (P < 0.05) of obesity, smoking, and high hostility score in all race/gender groups, and of physical inactivity in all groups except black men. Among whites, "heavy" TV viewers had higher depression scores, and among blacks, reported more alcohol use. TV viewing was not associated with hypertension and lipid abnormalities. Heavy TV viewing is a modifiable behavior that is associated with increased prevalence of several cardiovascular risk factors.

Change and secular trends in physical activity patterns in young adults: a seven-year longitudinal follow-up in the Coronary Artery Risk Development in Young Adults Study (CARDIA)

Levels and changes in self-reported physical activity over a 7-year period were examined to determine tracking and to estimate the proportion of total cohort change attributable to secular trends. A population-based sample of 2,328 men and 2,787 women aged 18-30 years at baseline (52% black and 48% white) from Birmingham, Alabama, Chicago, Illinois, Minneapolis, Minnesota, and Oakland, California, were examined four times between 1985-1986 and 1992-1993. The intraclass correlation for up to four measures was 0.57 for the entire sample, varying between 0.57 for white men and 0.42 for black women, indicating a moderate tendency for tracking. The energy expenditure in physical activity at each examination was greatest in black men and, compared with black men, about 5% less in white men, 30% less in white women, and 50% less in black women. The total cohort decrease in mean physical activity was approximately 30% in each race-sex group. The secular trend accounted for 38% of the total cohort change in black men, 43% in black women, 52% in white men, and 81% in white women. Physical activity declined sharply during the early years of adulthood, partly because of secular trend. Young adults are therefore an important target group for physical activity promotion programs to reverse individual and populationwide declines prior to middle age.

Migraine headache in a prepaid health plan: ascertainment, demographics, physiological, and behavioral factors

BACKGROUND

Migraine is a prevalent disorder whose relationship to other conditions remains poorly understood.

METHODS

Associations between migraine and physiological, behavioral, and demographic characteristics were assessed in a retrospective cohort study of 79,588 enrollees in a large prepaid health maintenance organization who underwent a multiphasic preventive health checkup in 1971-1973.

RESULTS

Migraine was found to be inversely associated with age and education and strongly associated with the female sex. The likelihood of migraine was significantly higher among blacks, smokers, those who drink more than six cups of coffee per day, those with Raynaud's syndrome, and those with a family history of migraine. The magnitude of associations between migraine and other factors was, in general, reduced among those with a self-reported physician diagnosis of migraine compared to those whose migraine status was defined on the basis of reported symptoms.

CONCLUSIONS

Migraine prevalence was found to be higher in blacks and other unspecified minorities than in the white population. The magnitude of the associations between migraine and behavioral risk factors was strongly influenced by the method of migraine ascertainment. The inverse association with level of education suggests that social causation or drift may have been operating in this disease in the early 1970s, 15 to 20 years earlier than recent population-based studies would suggest. Further research is needed to fully appreciate the spectrum of disease and behaviors associated with migraine.

Relationship of migraine headaches to experience of chest pain and subsequent risk for myocardial infarction

This study examined the relationship between migraine, chest pain, and risk of myocardial infarction (MI) in a retrospective cohort of 79,588 enrollees in the northern California Kaiser Permanente Medical Care Program who underwent comprehensive, multiphasic preventive medicine examinations in 1971 to 1973. Migraine was ascertained by questionnaire as either symptom-based or self-report of physician diagnosis. Chest pain was ascertained by two questions regarding feelings of pain, pressure, or tightness in the chest that either hurt in the middle under the breastbone or forced the respondent to stop walking. Follow-up began at the time of each participant's medical examination and continued until the earliest occurrence of hospitalization for MI, death, termination of enrollment, or December 1987. There was a strong relationship between migraine and chest pain, but, in general, no significant association was found between migraine and risk of MI except among women with a family history of MI in whom a self-reported physician diagnosis of migraine was related to a greater than two-fold increase in risk.