Acceleration of viral replication and up-regulation of cytokine levels by antimalarials: implications in malaria-endemic areas

Antimalarial drugs are widely used in malaria endemic areas, both for chemoprophylaxis and also empirically to treat patients presenting with fever. Previously, we have reported that chloroquine enhances the severity of Semliki forest virus (SFV) and encephalomyocarditis virus infection. The studies presented herein show that a broad spectrum of antimalarial drugs augmented the replication of SFV in mice, concomitant with greater tissue damage and up-regulation of mRNA levels of various inflammatory cytokine genes, including interleukin-1 receptor antagonist (IL-1Ra), II-1alpha, IL-1beta, IL-6, IL-12p40, and interferon-gamma inducing factor. Furthermore, chloroquine enhances IL-1Ra production in RAW cells in vitro. Since IL-1Ra is known to be up-regulated in a number of viral infections, we propose that a further enhancement of its expression by antimalarials may be responsible for the increased severity of viral infection in our studies. Thus, the widespread use of antimalarials in malaria-endemic areas may predispose the population to viral infections. Further studies are in progress to delineate mechanism(s) involved in cytokine up-regulation and acceleration of viral replication.

Serum uric acid and cardiovascular events in successfully treated hypertensive patients

To determine whether pretreatment and/or in-treatment serum uric acid (SUA) is independently and specifically associated with cardiovascular events in hypertensive patients, we examined the 20-year experience of 7978 mild-to-moderate hypertensive participants in a systematic worksite treatment program. Clinical evaluation and treatment were protocol-directed. SUA was measured at entry and annually thereafter. Subjects were stratified according to gender-specific quartile of baseline SUA. Blood pressures at entry and in-treatment were, respectively, 152.5/95.6 and 138.9/85.4 mm Hg. SUA was normally distributed with a mean of 0.399+/-0.0893 and 0. 321+/-0.0833 mmol/L for men and women, respectively. Subjects with highest SUA were heavier, had greater evidence of cardiovascular disease (CVD), higher systolic blood pressure, higher creatinine, more frequent diuretic use, and lower prevalence of diabetes. During an average follow-up of 6.6 years (52 751 patient-years), 548 CVD events (183 mortal) and 116 non-CVD events occurred. In bivariate analysis, the association of SUA to CVD was more robust in nonwhites than whites and in patients at low versus high CVD risk. In multivariate analysis, CVD incidence was significantly associated with SUA with a hazard ratio of 1.22 (95% confidence interval 1.11 to 1.35), controlling for other known cardiovascular risk factors, including serum creatinine, body mass index, and diuretic use. Despite blood pressure control, SUA levels increased during treatment and were significantly and directly associated with CVD events, independently of diuretic use and other cardiovascular risk factors.

Barriers and facilitators to providing common preventive screening services in managed care settings

Despite increasing emphasis on disease prevention and health promotion, and ample evidence demonstrating the effectiveness of preventive services, such services are underutilized in the United States. The current trend of health care toward health maintenance organizations and other managed care systems opens the door, perhaps to more effective control of heart disease, cancers and other chronic diseases through preventive care. This warrants attention to the barriers/facilitators to the provision/utilization of preventive screening services in such settings. Overall goal of this study was to assess barriers/facilitators to the provision/utilization of preventive services in managed care organizations (MCOs). This was accomplished by a) identifying barriers/facilitators to the provision/utilization of three common preventive screening services (cholesterol screenings, mammograms, and Pap smears); and b) profiling typical MCO recipients of these three preventive screening services. A self-administered, mail questionnaire was used to obtain information from a national sample of 1,200 Directors of MCOs associated with preventive care. A total of 175 usable responses were received resulting in a 17.3 percent net response rate. The strongest barrier to the provision of all three screening services is the inability of them to generate short term savings for the MCO. Other barriers include high disenrollment rates, conflicting recommendations about effectiveness (for mammograms and cholesterol screenings), and patients' fears of getting a positive result (for mammograms and Pap smears). The improved health status as a result of early intervention, high consumer awareness (for mammograms and Pap smears), and long term savings are important facilitators to the provision/utilization of these screening services. Comparing barriers and facilitators across the three services shows the stronger barriers affecting the provision/utilization of mammograms. For all three screening services, typical managed care recipients are those in the high income groups with greater education levels. However, with the increasing enrollment of Medicaid beneficiaries into managed care, MCOs may find themselves selectively targeting these high risk low income and less educated individuals to receive the preventive screening services. Study findings should be useful to health planners, policymakers and researchers at all levels in their efforts to encourage and promote healthier lifestyle choices among U.S. residents. Future studies should address receipt of preventive services by Medicaid and Medicare beneficiaries in managed care settings.

Persuasive messages. Development of persuasive messages may help increase mothers' compliance of their children's immunization schedule

Effective immunization campaigns can be designed by determining which persuasion strategy is most effective in attracting the attention of mothers of preschoolers. The authors assess the impact of three persuasional strategies: fear-arousal, motherhood-arousal, and rational messages, on mothers of preschoolers who are late for their immunizations. The fear-arousal message was found to be most effective, followed by the motherhood-arousal, and then the rational message, in attracting mothers' attention to their child's immunization status.

Diabetes and cardiovascular events in hypertensive patients

To determine the relation of self-reported history of diabetes as well as baseline and in-treatment blood sugar to subsequent cardiovascular disease (CVD) in treated hypertensive patients, we assessed the experience of 6886 participants in a systematic treatment program. The presence or absence of a history of diabetes was known for all patients, who were then stratified into 3 groups according to blood sugar at baseline and in treatment (<6.11, 6.11 to 7.74, and >/=7.75 mmol/L). Some 7.4% of all patients reported history of diabetes, and the overall prevalence of blood sugar >/=7. 75 mmol/L was 7.7% and 10.4% at baseline and in treatment, respectively. Patients with a history of diabetes were 10 or 8 times as likely to have blood sugar >/=7.75 mmol/L at baseline (47.2% versus 4.5%) or in treatment (55.0% versus 6.8%), as were patients without history. During an average 6.3 years of follow-up, patients with history of diabetes had a cardiovascular event incidence 2-fold higher than those without history (20.8 versus 8.6/1000 person-years). Age-gender-adjusted CVD incidence rate but not non-CVD was twice as high in the highest compared with the lowest blood sugar stratum (baseline 16.6 versus 8.4/1000 person-years; in treatment 15.2 versus 8.2). Three separate models of Cox multivariate analysis revealed that history of diabetes (with no history as reference) had a greater association with CVD events (hazard ratio 2.37, 95% confidence interval 1.80 to 3.11) than did baseline (1.75, 1.31 to 2.33) or in-treatment blood sugar (1.55, 1. 19 to 2.02). Furthermore, in the presence of history of diabetes (2. 15, 1.58 to 2.92), neither baseline nor in-treatment blood sugar was independently associated with CVD risk. In the elevated (>/=7.75 mmol/L) in-treatment blood sugar group, the age-gender-adjusted rate of CVD events in frequent diuretic users (30.79/1000 person-years) was significantly higher than in moderate (13.34, P=0.004) and rare users (13.25, P=0.008). These data affirm that the coincidence of diabetes and hypertension is common, that evidence of diabetes substantially increases CVD risk, that self-reported history is a more powerful predictor of CVD events than any measure of blood sugar, and that CVD increases in hypertensive diuretic users who develop hyperglycemia even when blood pressure is well controlled.

Picroliv -- a natural product protects cells and regulates the gene expression during hypoxia/reoxygenation

Cellular adaptation to hypoxia involves regulation of specific genes such as vascular endothelial growth factor (VEGF), erythropoietin (EPO) and hypoxia inducible factor (HIF)-1 . In this study, we have evaluated the protective effect of picroliv (a purified iridoid glycoside fraction from roots of Picrorhiza kurrooa with hepatoprotective, anti-inflammatory and antioxidant properties) against hypoxic injury by examining lactate dehydrogenase (LDH) release in Hep 3B and Glioma cells. The expression of hypoxia regulated genes, VEGF and HIF-1 was studied in human umbilical vein endothelial cells (HUVEC), Hep 3B and Glioma cells. Picroliv reduced the cellular damage caused by hypoxia as revealed by a significant reduction in LDH release compared to untreated control. The expression of VEGF and HIF-1 subunits (HIF-1alpha and HIF-1beta) was enhanced by treatment with picroliv during normoxia and hypoxia in HUVEC and Hep 3B cells and on reoxygenation the expression of these genes was significantly reduced as revealed by mRNA analysis using RT-PCR. Simultaneous treatment with picroliv during hypoxia inhibited VEGF and HIF-1 expression in Glioma cells whereas the expression was not reduced by picroliv treatment during reoxygenation as evidenced by both RT-PCR and Northern hybridization. VEGF expression as revealed by immunofluorescence studies correlates well with the regulations observed in the mRNA expression. We have also examined the kinase activity of tyrosine phosphorylated proteins and protein kinase C (PKC) in Glioma cells treated with picroliv during hypoxia/reoxygenation. A selective inhibition of protein tyrosine kinase activity leading to tyrosine dephosphorylation of several proteins including 80 kd protein, and a reduction in PKC was seen in cells treated with picroliv and hypoxia. These findings suggest that picroliv may act as a protective agent against hypoxia/reoxygenation induced injuries, and the underlying mechanism may involve a novel signal transduction pathway.

Predictors of childhood immunization completion in a rural population

Despite the availability of effective vaccines, immunization rates among two-year old children continue to be low in many areas of the United States including rural West Virginia. The goal of this study was to identify barriers to childhood immunization in rural West Virginia and determine factors that were important in the completion of the childhood immunization schedule. A telephone survey was used to collect data from a randomly selected sample of 316 mothers, of two-year olds, from 18 rural counties of West Virginia. Results indicated that two-thirds or 65% of the children in the study sample had completed their recommended immunizations by two years of age. Immunization barriers identified in this study include: living in health professional shortage areas, lack of health insurance, negative beliefs and attitudes regarding childhood immunizations, problems accessing the immunization clinic, and a perception of inadequate support from the immunization clinic. Results of the structural equation modeling, using LISREL-8, indicated that 20% of the variation in immunization completion (R2 = 0.197) was explained by attitude towards immunization and perceived support received from the immunization clinic. Furthermore, 42% of the variation in attitude towards immunization (R2 = 0.419) was explained by immunization-related beliefs, and 28% of the variation in immunization-related beliefs (the R2 = 0.277) was explained by general problems faced during immunization and perceived clinic support. The study concluded that positive immunization-related beliefs and attitudes, support from the immunization clinic, and ease of the immunization seeking process are important factors in the timely completion of the childhood immunization schedule.

Cardiovascular mortality of Chinese in New York City

To determine cardiovascular disease mortality among Chinese migrants in New York City and compare it to both that of residents in China and whites in New York City, mortality records for 1988 through 1992 for New York City and the 1990 US census data for New York City were linked. Age-specific death rates for urban China, reported by the World Health Organization, were used for comparison. The results show that male and female Chinese residents in New York City had lower mortality rates for all causes and total cardiovascular disease than did either New York City whites or Chinese in China. Coronary heart disease deaths among New York City Chinese were intermediate between Chinese in China (lowest) and New York City whites (highest). Stroke death rates for New York City Chinese were substantially lower than those in China and, in general, were similar to those for New York City whites. However, New York City Chinese had higher death rates for hemorrhagic stroke and lower for atherosclerotic stroke than did New York City whites. In conclusion, cardiovascular mortality rates among Chinese migrants in New York City fall below those of both Chinese in China and whites in New York City.

Low birth weight: race and maternal nativity--impact of community income

BACKGROUND

The purpose of this article is to determine the effect of community income as a co-factor in the association of low birth weight, race, and maternal nativity in New York City.

METHODS

New York City birth records, 1988 through 1994, provided data on maternal and infant characteristics. There were 274 121 white and 279 826 black mothers included in this study. Black mothers were classified as US-born (South and Northeast) and foreign-born (the Caribbean, South America, and Africa). Based on the 1990 US census income data, census tracts of the city were aggregated by tertile of per capita income as low-, middle-, and high-income communities. Incidence of low birth weight was estimated by race, maternal nativity in the city as a whole, and each income community.

RESULTS

Overall, black women had a substantially higher risk of low birth weight infants (<2500 g) than did whites (13.1% vs 4.8%). Foreign-born black mothers had a birth weight advantage over US-born black mothers (10.0% vs 16.7%). After controlling for socioeconomic and medical characteristics, the risks of low birth weight for blacks compared with whites were 0.95 (95% confidence interval: 0. 87-1.03) and 0.86 (0.69-1.02) for Caribbean- and African-born black mothers, respectively. Moreover, in low-income communities, compared with white mothers, the risks for Caribbean- and African-born black mothers were 0.88 (0.79-0.97) and 0.77 (0.61-0.96), respectively. By contrast, US and South American-born black mothers had a consistently higher risk of low birth weight infants, regardless of community income level.

CONCLUSION

Low birth weight was significantly less frequent among whites than among blacks. However, this overall finding masked substantial variation among blacks, determined by maternal nativity and the income level of the community in which they lived. In fact, Caribbean- and African-born black mothers had birth outcomes generally similar to and, in poor communities, even more favorable than those for whites.

The influence of maternal hypertension on low birth weight: differences among ethnic populations

OBJECTIVE

To determine the influence of maternal hypertension on the risk of low birth weight among white, black, and Hispanic residents of New York City.

METHODS

New York City birth certificates, 1988 through 1994, provided data on maternal and infant characteristics. Hypertension was self-reported on birth certificates, and was categorized as chronic or pregnancy-related hypertension. The complication of preeclampsia/eclampsia was also noted. The risk of low birth weight (<2500 grams) for maternal hypertension was determined.

RESULTS

The prevalence of hypertension during pregnancy was 3.8% overall, and was highest for blacks and lowest for whites. Low birth weight rates for white, black, and Hispanic babies were 5.0%, 12.8%, and 7.5%, respectively. Low birth weight rates among hypertensive mothers for whites, blacks and Hispanics were 16.8%, 24.4% and 19.5% respectively. The trends were similar for chronic and pregnancy-related hypertension, as well as for preeclampsia/eclampsia. The relative risk of low birth weight offspring among all hypertensive mothers was highest among whites (3.58, 95% CI = 3.39-3.79), and lowest among blacks (1.99, 95% CI = 1.93-2.06). This trend persisted for chronic and pregnancy-related hypertensive mothers, and those with preeclampsia/eclampsia, after adjusting for other maternal socioeconomic characteristics. Due to the higher prevalence of hypertension among black mothers, the population attributable risk of low birth weight was highest among black babies (557 per 100,000 live births) and lowest among whites (309 per 100,000 live births).

CONCLUSION

Maternal hypertension is an important risk factor for low birth weight. Its impact, however, differed by race/ethnicity groups.

Residential segregation and mortality in New York City

The objective of this research was to determine the effect of residential racial segregation on all-cause and cardiovascular disease mortality in New York City. A cross-sectional study of residents in New York City was conducted linking mortality records from 1988 through 1994, to the 1990 United States Census data stratified by zipcode. All-cause and cardiovascular disease mortality rates for non-Hispanic blacks and whites were estimated by zipcode. Zipcodes were aggregated according to the degree of residential segregation (predominantly (> or = 75%) white and black areas) and mortality rates were compared. Multiple regression analysis was used to associate population characteristics with mortality. In New York City, although overall mortality rates of blacks exceed whites, these rates varied substantially by locality according to the pattern of racial segregation. Whites living in the higher (mainly white) socioeconomic areas had lower mortality rates than whites living in predominantly black areas (1473.7 vs 1934.1 for males, and 909.9 vs 1414.7 for females for all-cause mortality). This was true for all age groups. By contrast, elderly blacks living in black areas, despite their less favorable socioeconomic status, had lower mortality rates for all-cause, total cardiovascular disease, and coronary heart disease, than did those living in white areas, even after adjusting for available socioeconomic variables. Racial segregation in residence is independently associated with mortality. Within racially segregated areas, members of the dominant group, for all age, among whites and elderly blacks, enjoy outcomes superior both to members of the minority racial group of their community, and to members of the same race residing in other areas, where they are in the minority, independent of socio-economic status.

Epidemiology of risk in hypertensives: experience in treated patients

Knowledge of the epidemiology of cardiovascular disease (CVD) in hypertensive patients derives primarily from observation of populations composed largely of untreated subjects. Increasingly, however, individuals with elevated blood pressure are treated. An 18-year observational study of 8690 participants in a systematic hypertension control project reveals that cardiovascular events continue to be the principal morbid and mortal outcomes. Over time, the incidence of stroke and heart attack remained stable, whereas congestive heart failure (CHF), as a first event, increased tenfold after 10 years. Diabetes and evidence of vascular disease at entry predicted morbidity. Persisting cardiovascular morbidity in the face of satisfactory blood pressure control suggests the need for additional preventive intervention.

Distribution and determinants of cardiovascular events during 20 years of successful antihypertensive treatment

OBJECTIVE

To define the distribution and determinants of cardiovascular disease events among participants undergoing long-term antihypertensive therapy, and to stratify them into risk groups on the basis of pretreatment clinical profiles.

DESIGN

A prospective cohort study of participants in a worksite-based antihypertensive treatment program in New York city (1973-1994).

PATIENTS

We studied 8690 systematically treated patients who had at least 6 months of follow-up (average of 5.7 years) and, at entry, had had a systolic blood pressure of > or = 160 mmHg or a diastolic blood pressure of > or = 95 mmHg (after 1992 > or = 140/90 mmHg), or had been being administered antihypertensive medication.

MAIN OUTCOME MEASURES

Blood pressure and incidence of morbid and mortal cardiovascular events.

RESULTS

Blood pressure control (to 140 +/- 3/87 +/- 7 mmHg) was achieved by the first year and maintained through 18 years of therapy. In nearly 50,000 person-years of follow-up, there were 468 cardiovascular disease events [myocardial infarction including revascularization (282), strokes (93), congestive heart failure (30) and other cardiovascular deaths (63)]. Deaths from cardiovascular disease events accounted for 68% of all deaths. Myocardial infarction was most common throughout, but congestive heart failure incidence surpassed stroke incidence after 10 years. A scheme for risk stratification was constructed after analysis of the independent association of baseline factors and incident cardiovascular events. Upon the basis of ease of ascertainment and their demonstrated associations with occurrence of cardiovascular disease during treatment, we selected five pretreatment factors (history of heart attack, stroke, diabetes, age > or = 55 years and pulse pressure > or = 60 mmHg) to stratify patients into four groups. Those with no risk factor had a low risk (n=2999), those with one had a moderate risk (3042), those with two had a high risk (2237), and those with three or more had a very high risk (412). Overall, the unadjusted rates of incidence of cardiovascular disease events per 1000 person-years for patients in very high and low risk groups differed by factors of six and 14 for men and women, respectively.

CONCLUSION

These results demonstrate that long-term control of blood pressure can be achieved in a general population. Nevertheless, cardiovascular disease events still accounted for most morbidity and mortality among these 'recovered' hypertensive patients. At entry, on the basis of readily identifiable characteristics, it was possible to stratify patients according to likelihood of subsequent events occurring despite control of blood pressure. This scheme could provide the basis for targeting more aggressive therapy where the potential for further cardioprotection is greatest.

Dietary sodium intake and mortality: the National Health and Nutrition Examination Survey (NHANES I)

BACKGROUND

Population-wide restriction of dietary sodium has been recommended. However, little evidence directly links sodium intake to morbidity and mortality. The aim of this study was to assess the relation of sodium intake to subsequent all-cause and cardiovascular-disease (CVD) mortality in a general population.

METHODS

The first National Health and Nutrition Examination Survey established baseline information during 1971-75 in a representative sample of 20729 US adults (aged 25-75). 11348 underwent medical examination and nutritional examination based on 24 h recall. Two had no data on sodium intake available. Vital status at June 30, 1992, was obtained for the 11346 participants through interview, tracing, and searches of the national death index. Mortality was examined in sex-specific quartiles of sodium intake, calorie intake, and sodium/calorie ratio. Multiple regression analyses were done to assess the relations with mortality.

FINDINGS

There were 3923 deaths, of which 1970 were due to CVD. All-cause mortality (per 1000 person-years; adjusted for age and sex) was inversely associated with sex-specific quartiles of sodium intake (lowest to highest quartile 23.18 to 19.01, p<0.0001) and total calorie intake (25.03 to 18.40, p<0.0001) and showed a weak positive association with quartiles of sodium/calorie ratio (20.27 to 21.71, p=0.14). The pattern for CVD mortality was similar (sodium 11.80 to 9.60, p<0.0019; calories 12.80 to 8.94, p<0.0002; sodium/calorie ratio 9.73 to 11.35, p=0.017). In Cox multiple regression analysis, sodium intake was inversely associated with all-cause (p=0.0069) and CVD mortality (p=0.086) and sodium/calorie ratio was directly associated with all-cause (p=0.0004) and CVD mortality (p=0.0056). By contrast, calorie intake in the presence of the two measures of sodium intake was not independently associated with mortality (all-cause p=0.86; CVD p=0.74). Analysis restricted to participants with no history of CVD at baseline gave similar results.

INTERPRETATION

This observational study does not justify any particular dietary recommendation. Specifically, these results do not support current recommendations for routine reduction of sodium consumption, nor do they justify advice to increase salt intake or to decrease its concentration in the diet.

Nativity, race, and mortality: favorable impact of birth outside the United States on mortality in New York City

To determine the association of birthplace (US-born vs. foreign-born) with mortality among blacks and whites in New York City, we examined death records for 5 years from 1988 to 1992 and the 1990 census data. Mortality rates by race and birthplace were compared for all causes of death and for specific causes. Although overall death rates for blacks generally exceeded those for whites (1224.8 per 100,000 inhabitants vs. 721.4 for males and 593.7 vs. 393.1 for females), foreign-born blacks had death rates (664.6 for males and 350.2 for females) slightly lower than those for whites. The most striking variation among blacks was among those aged 25 to 64 years. US-born black males were three times as likely (1588.9 vs. 525.2) and US-born black females were more than 2.5 times as likely (673.5 vs. 263.4) to die as were foreign-born blacks. Among US-born blacks AIDS, homicide, and cancer for males and AIDS, heart disease, and cancer for females were the most important determinants of excess deaths, defined as the difference between observed deaths and expected deaths; these causes of death account for about half of the excess deaths for each sex. Among whites natives generally had higher death rates than migrants, but less prominently and consistently so than for blacks. Excess mortality of blacks is largely explained by higher death rates of US-born compared with foreign-born Americans.

Nativity, race, and mortality: influence of region of birth on mortality of US-born residents of New York City

Among non-Hispanic black and white residents of New York City the association between birthplace by region (South, West/ Midwest, and Northeast) within the United States and mortality was determined by linking mortality records for 1988-1992 with the 1990 United States census data for New York City. Age-adjusted death rates computed by birthplace for blacks and whites were examined and also compared with total US data. The results indicate that death rates for New Yorkers generally exceed those of the United States overall, and black rates exceed those of whites. Moreover, Southern-born blacks have substantially higher death rates than do blacks born in the Northeast. The most striking variations are for cancer and diseases of the heart. Deaths from AIDS and homicide are higher among blacks than among whites, but the rates for Southern-born blacks do not exceed those for Northeastern-born blacks. For whites those born in the South have higher death rates overall than those born in the Northeast, but differences in cause-specific mortality are less consistent than for blacks. The results reveal substantial heterogeneity of health status based on nativity, among blacks in particular. To understand the role of the related factors, both genetic and environmental, further population and epidemiologic studies are important.

Influence of nativity on cancer mortality among black New Yorkers

BACKGROUND

Cancer is the second leading cause of death in U. S., and blacks have higher cancer death rates than whites. The authors conducted an analysis to determine the influence of birthplace on cancer mortality among blacks in New York City.

METHODS

Death records for New York City from 1988 through 1992 were linked to the 1990 U. S. Census data. Age-adjusted cancer death rates by race and birthplace were computed. The experience of black residents born in the South and Northeast of the U. S. and in Caribbean countries were compared with that of New York City whites.

RESULTS

The cancer mortality rate of blacks exceeded that of whites for males (512.6 vs. 385.6 per 100,000 per year), but was similar for females (270.8 vs. 270.6). However, cancer death rates of Southern-born black males (615.7) were substantially higher than those of black males born in the Northeast (419.1) or the Caribbean (352.4). Carcinomas of the lung, prostate, breast, and colon/rectum accounted for >50% of all cancer deaths. Lung carcinoma mortality varied greatly by birthplace, with Caribbean-born blacks (63.5 and 19.2 for males and females, respectively) having approximately one-third the death rates of Southern-born blacks (187.8 and 52.5 for males and females, respectively), and <50% that of New York City whites (108.7 and 53.2 for males and females, respectively). These differences were present in each age category, but were most pronounced among those age 45-64 years. In striking contrast, death rates from prostate carcinoma were highest in Caribbean-born black men, and this was especially apparent in persons age > or = 65 years.

CONCLUSIONS

The generally higher cancer mortality of blacks compared with whites masks even greater intraracial heterogeneity revealed through stratification by birthplace. In general, Caribbean-born blacks are at lower risk of cancer mortality than other blacks, and whites, but their advantage does not hold for prostate carcinoma, for which Caribbean-born men had the highest mortality rate.

The gift relationship between pharmaceutical companies and physicians: an exploratory survey of physicians

The purpose of this exploratory study was to survey physicians' attitudes surrounding the 'gift relationship' between pharmaceutical companies and physicians. A survey was mailed to 1000 randomly selected West Virginia physicians, of which 283 (28.3%) responses were received. The most commonly received gifts reported by the study physicians were trinkets (77.4%), followed by books (41.7%) and meals (41%). Principal component analysis and varimax rotation identified seven physician belief constructs. The mean ratings of the constructs indicated that the physicians slightly agreed that pharmaceutical companies give gifts to physicians to influence their prescribing, moderately disagreed that they do so as a form of professional recognition of physicians, and strongly disagreed that their prescribing behaviour could be influenced by the gifts they receive. Physicians slightly disagreed that pharmaceutical companies' sponsoring of CME programmes are only promotional gimmicks. Although the study physicians slightly disagreed that it may be inappropriate for them to accept gifts from pharmaceutical companies, they seemed slightly averse to having 'gift relationships' between pharmaceutical companies and physicians made public. Correlation analysis suggested that physicians who have a large number of patients in their practice, see a larger number of patients per day, or write a large number of prescriptions per day are more likely to be offered gifts by pharmaceutical companies, and they are also more likely to condone the practice of gift giving and receiving.

Effect of long-acting and short-acting calcium antagonists on cardiovascular outcomes in hypertensive patients

BACKGROUND

Short-acting calcium antagonists may increase coronary artery morbidity, mortality, and non-cardiovascular complications in hypertensive patients. We assessed whether this association was also true for long-acting calcium antagonists.

METHODS

We did a case-control study, which was nested within a systematic hypertension control programme for a prospective cohort of 4350 people (first seen 1981-94). Cases (n = 189) were hypertensive patients who had had a first cardiovascular event, including all cardiovascular deaths and hospitalisations, between 1989 and 1995. Controls (n = 189) were individually matched to cases for sex, ethnic origin, age, type of previous antihypertensive treatment, year of entry into the study, and length of follow-up. We collected data on any prescribed drug regimen that was being taken on the event data for cases and on the same date for matched controls. Calcium antagonists were classified by duration of action.

FINDINGS

Compared with those on beta-blocker monotherapy, patients on long-acting calcium antagonists (n = 136) had no increased risk of a cardiovascular event (adjusted odds ratio 0.76 [95% CI 0.41-1.43]), whereas patients on short-acting calcium antagonists (n = 27) were at significantly greater risk (adjusted odds ratio 3.88 [1.15-13.11], p = 0.029). Among 38 matched pairs who were both on calcium antagonists, the adjusted risk ratio for short-acting versus long-acting was 8.56 (1.88-38.97), p < 0.01.

INTERPRETATION

Long-acting and short-acting calcium antagonists differ in cardiovascular outcomes. Consistent with earlier findings, the use of short-acting calcium antagonists was associated with increased risk of a cardiovascular event. This finding highlights the need to complete on-going clinical trials so that the relative cardiovascular impact of various antihypertensive agents can be assessed.

Urinary sodium excretion and myocardial infarction in hypertensive patients: a prospective cohort study

Reduced-sodium diets are frequently recommended for hypertensive patients. To determine the relation of sodium intake to subsequent cardiovascular disease, 24-h urinary excretion of sodium, potassium, and creatinine and plasma renin activity (PRA) were measured in 2937 mildly and moderately hypertensive patients unmedicated for > or = 3-4 wk. Morbidity and mortality in these treated subjects were ascertained. Subjects were stratified by sex-specific quartiles of urinary sodium excretion; race, cardiovascular status, and blood pressure before and during treatment were similar for each stratum. Patients with lower urinary sodium excretion were thinner, excreted less potassium, and had higher PRA. During an average 3.8-y follow-up, 55 myocardial infarctions (MIs) occurred. Incidence of MIs and urinary sodium excretion were inversely associated in the total population and in males but not in females. In males, age- and race-adjusted MI incidence in the lowest compared with the highest quartile of urinary sodium excretion was 11.5 compared with 2.5 (RR: 4.3; 95% CI: 1.7, 10.6). No association was observed between mortality from causes other than cardiovascular disease (n = 11) and urinary sodium excretion. There was a significant linear trend in proportions of MI by quartile of urinary sodium excretion, with a breakpoint after the lowest quartile. In Cox multivariate analysis, the logarithm of PRA, age, systolic blood pressure, and cholesterol as continuous variables, as well as left ventricular hypertrophy and smoking, had a direct association and urinary sodium excretion an inverse, independent association (P = 0.036) with incidence of MI.

The influence of birthplace on mortality among Hispanic residents of New York City

To determine the mortality experience of Hispanic residents of New York City and the influence of birthplace on their mortality rates, NYC Department of Health mortality records for 1988 to 1992 were linked for analysis with 1990 United States census data for New York City. Age-specific death rates for all Hispanics were compared by birthplace with those of non-Hispanic whites. Age-adjusted death rates were also compared. Overall, Hispanics had death rates lower than non-Hispanic blacks, and death rates similar to those of non-Hispanic whites. Hispanics had higher rates of death from HIV-infection, diabetes, stroke/hypertensive disease, cirrhosis and homicide, and fewer deaths from cancer and coronary heart disease than did non-Hispanic whites. Moreover, there were substantial differences in mortality between Hispanic subgroups categorized by birthplace. Migrants from Puerto Rico had the highest, and those from Central and South America the lowest mortality rates. United States-born Hispanics, although younger, had age-adjusted mortality rates higher than New York City non-Hispanic whites. In summary, the mortality of Hispanics generally approximated that of non-Hispanic whites, and was lower than that of non-Hispanic blacks. However, stratification of Hispanics by birthplace revealed substantial variation within the Hispanic population of New York City.