Consanguinity, prematurity, birth weight and pregnancy loss: a prospective cohort study at four primary health center areas of Karnataka, India.

OBJECTIVE: To determine whether consanguinity adversely influences pregnancy outcome in South India, where consanguinity is a common means of family property retention. STUDY DESIGN: Data were collected from a prospective cohort of 647 consenting women, consecutively registered for antenatal care between 14 and 18 weeks gestation, in Belgaum district, Karnataka in 2005. Three-generation pedigree charts were drawn for consanguineous participants. χ (2)-Test and Student's t-test were used to assess categorical and continuous data, respectively, using SPSS version 14. Multivariate logistic regression adjusted for confounding variables. RESULT: Overall, 24.1% of 601 women with singleton births and outcome data were consanguineous. Demographic characteristics between study groups were similar. Non-consanguineous couples had fewer stillbirths (2.6 vs 6.9% P=0.017; adjusted P=0.050), miscarriages (1.8 vs 4.1%, P=0.097; adjusted P=0.052) and lower incidence of birth weight <2500 g (21.8 vs 29.5%, P=0.071, adjusted P=0.044). Gestation <37 weeks was 6.2% in both the groups. Adjusted for consanguinity and other potential confounders, age <20 years was protective of stillbirth (P=0.01), pregnancy loss (P=0.023) and preterm birth (P=0.013), whereas smoking (P=0.015) and poverty (P=0.003) were associated with higher rates of low birth weight. CONCLUSION: Consanguinity significantly increases pregnancy loss and birth weight <2500 g.

Drape estimation vs. visual assessment for estimating postpartum hemorrhage.

OBJECTIVE: To compare (1) visual estimation of postpartum blood loss with estimation using a specifically designed blood collection drape and (2) the drape estimate with a measurement of blood loss by photospectrometry. METHODS: A randomized controlled study was performed with 123 women delivered at the District Hospital, Belgaum, India. The women were randomized to visual or drape estimation of blood loss. A subsample of 10 drape estimates was compared with photospectrometry results. RESULTS: The visual estimate of blood loss was 33% less than the drape estimate. The interclass correlation of the drape estimate to photospectrometry measurement was 0.92. CONCLUSION: Drape estimation of blood loss is more accurate than visual estimation and may have particular utility in the developing world. Prompt detection of postpartum hemorrhage may reduce maternal morbidity and mortality in low-resource settings.

Conducting international collaborative research in developing nations.

International research partnerships bring together some of the best and the brightest in an effort to tackle global health problems. Such collaborations also pose complex challenges, such as maintaining ethical principles in the conduct of research in developing nations. In implementing a randomized clinical trial to reduce postpartum hemorrhage (PPH) during childbirth in rural India, U.S. and Indian collaborators addressed three such issues: the appropriateness of an ethical randomized controlled trial in the developing world, the inclusion of a placebo arm, and the relevance of informed consent in a semiliterate rural population.

Secular trends in Q wave and non-Q wave acute myocardial infarction. The Minnesota Heart Survey.

The Minnesota Heart Survey examined trends of Q wave and non-Q wave acute myocardial infarction (AMI) using a 50% random sample of all hospital discharges of patients with AMI or another acute coronary disease from 35 of 36 hospitals in 1970 and 30 of 31 hospitals in 1980 in the Minneapolis-St. Paul metropolitan area. A total of 1,901 and 1,864 potential AMI cases were abstracted in 1970 and 1980, respectively. Electrocardiograms were coded according to the Minnesota code. AMIs were validated by computerized algorithm based on chest pain, enzymes, electrocardiograms, and autopsy. This study shows that with the use of a consistent, standard diagnostic algorithm, attack rates for Q wave AMI did not change significantly between 1970 and 1980 and that attack rates for non-Q wave AMI decreased significantly during the same decade. However, when the more sensitive cardiac enzymes creatine phosphokinase and creatine phosphokinase-MB were considered, attack rates of both Q wave and non-Q wave AMIs increased. This research documents four important trends for community AMI rates that are at variance with those reported by others. There was a decline in non-Q wave AMI attack rates from 1970 to 1980; women had outcomes equal to or worse than those for men for both case-fatality and 7-year survival rates; patients with non-Q wave AMIs had worse in-hospital prognoses than those with Q wave AMIs; and 7-year survival rates were worse for Q wave AMI in 1980. These findings demonstrate the need for standard diagnostic criteria for Q wave and non-Q wave AMI if trends are to be monitored. In the future, as new trials of operative and nonoperative therapies of AMI are undertaken, these considerations will increase in importance.

The effect of the number of electrocardiograms analyzed on cardiovascular disease surveillance: the Minnesota Heart Survey (MHS).

One method used to control costs in community cardiovascular disease surveillance is to limit the number of electrocardiograms (ECGs) used to validate acute myocardial infarction (AMI). The Minnesota Heart Survey investigated the impact of decreasing the maximum number of ECGs analyzed on classification of ECG pattern and final AMI diagnosis (definite, probable, none). A 50% sample of all 1980 acute CHD hospital discharge records (ICD-9 code 410 or 411) from 30 of 31 Twin Cities hospitals were abstracted. Comparing results using all available ECGs in the record (maximum of 12) with those obtained using up to 4 ECGs showed little differences in the ECG classification or final AMI diagnosis.

The effects of diagnostic criteria on trends in coronary heart disease morbidity: the Minnesota Heart Survey.

The Minnesota Heart Survey assessed attack rates of MI in Twin Cities residents ages 30-74 years in 1970 and 1980. The age-adjusted attack rate per 100,000 of definite MI was similar in 1970 (174.2) and 1980 (179.9) p greater than 0.05, using ECG, chest pain, and blood enzyme concentrations of aspartate transaminase and/or lactic dehydrogenase as criteria. The attack rate of definite MI also remained constant when autopsy findings were included in the algorithm, 197.0 in 1970 and 191.4 in 1980 (p greater than 0.05). Adding creatine phosphokinase (CPK) and CPK-MB isoenzyme to the algorithm increased the rate of definite MIs from 209.0 in 1970 to 277.0 in 1980 (p less than 0.001). Interpretation of long-term trends in coronary heart disease morbidity is highly dependent upon variables used to validate cases. Care must be taken to maintain consistent criteria to avoid bias due to improvements in diagnostic techniques over time which increase sensitivity for detection of cardiac ischemia.

Prevalence of cardiovascular disease risk factors in blacks and whites: the Minnesota Heart Survey.

Two cross-sectional surveys were conducted in 1985 and 1986 to measure the prevalence of coronary heart disease (CHD) risk factors in Blacks and Whites. A home interview was followed by a survey center visit. Participation rates were 78 per cent and 90 per cent for the home interview and 65 per cent and 68 per cent for the survey center visit. Adjusted for age and education, systolic and diastolic blood pressure was 3 to 4 mmHg higher in Blacks. Hypertension was more prevalent in Blacks than Whites (44 per cent vs 28 per cent); serum total cholesterol was approximately 0.4 mmol/l lower in Black than White men and 0.08 mmol/l lower in Black than White women. Among men, more Blacks than Whites were current cigarette smokers (44 per cent vs 30 per cent); however, White smokers smoked more cigarettes per day (26 vs 17). Similar differences were noted for women, although the prevalence and quantity of cigarette consumption was less than men. The excess prevalence of these CHD risk factors in Blacks, especially among women, may explain their elevated CHD and stroke mortality rates in the Twin Cities.

Use of aspirin for prevention of cardiovascular disease--1981-82 to 1985-86: the Minnesota Heart Survey.

The efficacy of aspirin to prevent ischemic cardiovascular disease has received considerable attention recently. To determine the prevalence of aspirin use for cardiovascular disease prevention, the Minnesota Heart Survey examined population-based samples of Twin Cities' adults in 1981 to 82 and 1985 to 86. Over the 4-year period, reported use of aspirin for cardiovascular disease prophylaxis increased from 0.6% to 2.4% in women (p less than 0.05) and from 1.7% to 3.3% in men (p = 0.10). Prophylactic aspirin use was more common in older than in younger adults, in whites than in blacks, in those with a history of cardiovascular disease or hypercholesterolemia, and in health professionals and nonsmokers. Some individuals were apparently taking aspirin for "primary" prevention, although it has not yet been approved for that reason. Use of aspirin for cardiovascular disease prevention has been increasing and is likely to increase more rapidly over the next few years. This could favorably impact on mortality rates of cardiovascular disease, but untoward side effects of aspirin may be expected to increase as well.

Comparability of mortality follow-up before and after the National Death Index.

Prior to 1979, epidemiologic studies which included mortality follow-up on large cohorts relied on death certificates from last state of residence and expensive follow-up techniques to determine survival. Beginning with 1979, the National Death Index can be used to search death certificate files from all 50 states, the Virgin Islands, and Puerto Rico. This paper addresses the issue of whether mortality follow-up in epidemiologic studies based on a single state death certificate search using only data available in 1970-1975 can be compared with post-1979 mortality follow-up using the National Death Index. This question was addressed by following a cohort of 2,925 coronary heart disease and cerebrovascular disease 1980 hospital discharges from 1980 through 1983 with the use of both the National Death Index and the Minnesota Death Index (MINNDEX). Algorithms for evaluating potential death certificate matches were developed independently for both systems. The systems agreed on the survival status of 98% of the cohort, and both identified 31% as dead. This study supports the comparison of results of National Death Index follow-up to pre-National Death Index studies using algorithms such as the MINNDEX, and provides evidence that trend analyses relying on single state death searches pre-1979 and on the National Death Index from 1979 are valid, particularly in chronically ill persons.

Prevalence of coronary heart disease risk factors in an urban black population: the Minnesota Heart Survey, 1985.

A cross-sectional study of a sample of Minnesota black urban residents was conducted in 1985 to develop cardiovascular risk profiles. Participants were evaluated during a home interview (N = 1,254, 78% participation) and a survey center visit (N = 1,052, 65% participation). Black men had significantly higher mean systolic and diastolic blood pressure than Black women (129.7/80.9 vs 124.8/77.3, respectively). Age-specific values for systolic and diastolic blood pressure were greater in men than women for all age categories. Men were more likely to have uncontrolled hypertension or to be unaware of their hypertension than women in all age categories. Women had significantly higher mean total and high-density lipoprotein cholesterol values than men (202.1 and 56.1 mg/dl vs 193.2 and 48.7 mg/dl, respectively). Age-specific values for total and high-density lipoprotein cholesterol values were greater in women than men for all age categories except the 35-44 age group. Men were significantly more likely to be current cigarette smokers (43.3% vs 33.2%) and to have higher cigarette consumption per day (17 vs 14) than women. The major risk factors for cardiovascular disease (with the exception of smoking) were lower in the Minnesota study in 1985 than in the National Health and Nutrition Examination Survey in 1976-1980. These lower levels may also be a component in the decline of cardiovascular disease mortality rates among Blacks.

Postmarketing surveillance methodologies.

This article describes and discusses the strengths and limitations of the major pharmacoepidemologic methodologies employed in postmarketing drug surveillance and describes the current status of the U.S. surveillance system. The main methodologies employed in postmarketing drug surveillance include controlled clinical trials, observational epidemiologic studies (cohort, case-control, cross-sectional), demographic methods, drug utilization surveys, spontaneous reports, and automated databases linking medications and disease. Examples of pharmacoepidemiologic studies using each of these methodologies are presented. When a question arises about the efficacy and/or safety of a marketed drug, typically a mixture of these study methodologies is employed. The article concludes with a brief discussion of the role of the Food and Drug Administration, pharmaceutical manufactures, and academic institutions in initiating and conducting postmarketing drug studies.

Trends in cardiovascular risk factors in an urban black population, 1973-74 to 1985: the Minnesota Heart Survey.

Cardiovascular disease mortality rates have fallen dramatically in blacks in the United States. To determine whether this may be due to a decline in cardiovascular risk factors, we compared risk factors in a 1985 urban black population, ages 35 to 69, with those obtained in blacks of the same area in 1973-74. Age-adjusted mean body mass and the prevalence of overweight increased significantly over the 12-year period in both men and women. Mean systolic blood pressures declined significantly in both sexes, diastolic blood pressure declined significantly in men, and the proportion of men and women hypertensives on medication and under control increased. The overall prevalence of cigarette smoking changed very little, but the proportion of heavy smokers decreased significantly in men. No significant changes occurred in resting heart rate. Concurrently with these risk factor trends, age-adjusted heart disease mortality rates in area blacks fell 27% between 1968-73 and 1979-84, and stroke mortality fell 58%. Changing risk factors may be contributing to declining cardiovascular mortality rates in blacks. However, overweight seems to be a worsening problem.

Improvement in long-term survival among patients hospitalized with acute myocardial infarction, 1970 to 1980. The Minnesota Heart Survey.

The mortality rate associated with coronary heart disease in the United States has declined steadily since 1968, but the reasons for this favorable trend have not been completely elucidated. In particular, it is not clear to what extent the decline reflects decreasing incidence as opposed to improved survival. To assess whether improved survival after myocardial infarction has contributed to the decline, the Minnesota Heart Survey compared the four-year survival rate in patients discharged with a diagnosis of acute myocardial infarction from hospitals in the Twin Cities area in 1970 and 1980. After adjustment for clinical characteristics related to outcome, the survival rate among patients with a definite myocardial infarction was significantly higher in the 1980 than in the 1970 group. The four-year survival for men was 35 percent better in the 1980 than in the 1970 group (95 percent confidence interval, 21 to 50 percent), and for women it was 27 percent better (95 percent confidence interval, 1 to 46 percent). Improvement in survival during the period of hospitalization accounted for 70 percent of the overall gain in survival between 1970 and 1980 in men and for virtually all of the gain in women. We conclude that improved long-term survival among patients with acute myocardial infarction has made an important contribution to the decline in mortality from coronary disease.

A potential use of the National Death Index for postmarketing drug surveillance.

A particularly difficult problem for both the Food and Drug Administration and the pharmaceutical manufacturer is evaluation of the importance of spontaneous reports of suspected drug-associated fatalities. These reports are rare, and usually no accurate denominator data on drug use exist. This article proposes that the National Death Index be used to calculate mortality rates for selected drugs as part of the postmarketing surveillance efforts of the government and manufacturers. When hypotheses are generated from spontaneous reports and/or the mortality data, additional studies can be conducted on the cohorts that were identified for mortality follow-up.