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Tall stature and obesity have been associated with a higher risk of atrial fibrillation (AF), but there have been conflicting reports of the effects of aerobic fitness. We conducted a national cohort study to examine interactions between height or weight and level of aerobic fitness among 1,547,478 Swedish military conscripts during 1969-1997 (97%-98% of all 18-year-old men) in relation to AF identified from nationwide inpatient and outpatient diagnoses through 2012 (maximal age, 62 years). Increased height, weight, and aerobic fitness level (but not muscular strength) at age 18 years were all associated with a higher AF risk in adulthood. Positive additive and multiplicative interactions were found between height or weight and aerobic fitness level (for the highest tertiles of height and aerobic fitness level vs. the lowest, relative excess risk = 0.51, 95% confidence interval (CI): 0.40, 0.62; ratio of hazard ratios = 1.50, 95% CI: 1.34, 1.65). High aerobic fitness levels were associated with higher risk among men who were at least 186 cm (6 feet, 1 inch) tall but were protective among shorter men. Men with the combination of tall stature and high aerobic fitness level had the highest risk (for the highest tertiles vs. the lowest, adjusted hazard ratio = 1.70, 95% CI: 1.61, 1.80). These findings suggest important interactions between body size and aerobic fitness level in relation to AF and may help identify high-risk subgroups.

Background: Ultraviolet radiation (UVR) exposure is the main risk factor for cutaneous malignant melanoma (CMM), but its specific effect in infancy is unknown. We examined whether season of birth, a proxy for solar UVR exposure in the first few months of life, is associated with CMM in childhood through young adulthood., Methods: National cohort study of 3,571,574 persons born in Sweden in 1973-2008, followed up for CMM incidence through 2009 (maximum age 37 years) to examine season of birth and other perinatal factors., Results: There were 1595 CMM cases in 63.9 million person-years of follow-up. We found a sinusoidal pattern in CMM risk by season of birth (P=0.006), with peak risk corresponding to birthdates in spring (March-May). Adjusted odds ratios for CMM by season of birth were 1.21 [95% confidence interval (CI), 1.05-1.39; P=0.008] for spring, 1.07 (95% CI, 0.92-1.24; P=0.40) for summer and 1.12 (95% CI, 0.96-1.29; P=0.14) for winter, relative to fall. Spring birth was associated with superficial spreading subtype of CMM (P=0.02), whereas there was no seasonal association with nodular subtype (P=0.26). Other CMM risk factors included family history of CMM in a sibling (>6-fold) or parent (>3-fold), female gender, high fetal growth and high paternal education level., Conclusions: In this large cohort study, persons born in spring had increased risk of CMM in childhood through young adulthood, suggesting that the first few months of life may be a critical period of UVR susceptibility. Sun avoidance in early infancy may play an important role in the prevention of CMM in high-risk populations., (© The Author 2014; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.)

The incidence of Hodgkin lymphoma has increased among adolescents and young adults in recent decades, but the relevant risk factors in early life are still unknown. A national cohort study was conducted of 3,571,574 individuals born in Sweden in 1973-2008 and followed up for Hodgkin lymphoma incidence through 2009, to examine perinatal and family risk factors for Hodgkin lymphoma in childhood through young adulthood (ages 0-37 years). There were 943 Hodgkin lymphoma cases identified in 66.3 million person-years of follow-up. High fetal growth was associated with an increased risk of Hodgkin lymphoma after adjustment for gestational age at birth and other potential confounders (P(trend) = 0.005). Family history of Hodgkin lymphoma in a sibling or parent also was strongly associated with an increased risk, with adjusted hazard ratios = 8.83 (95% confidence interval: 3.67, 21.30) and 7.19 (95% confidence interval: 3.58, 14.44), respectively. No association was found between gestational age at birth, birth order, twinning, parental age, or parental education and Hodgkin lymphoma. These findings did not vary by age at Hodgkin lymphoma diagnosis. Similar associations were found for nodular sclerosis and mixed cellularity subtypes. These findings suggest that perinatal factors including possible growth factor pathways may contribute to the risk of Hodgkin lymphoma in childhood through young adulthood.

Background: The incidence of non-Hodgkin lymphoma (NHL) in early life has increased in recent decades, but the relevant risk factors remain largely unknown. We examined perinatal and family risk factors for NHL in childhood through young adulthood., Methods: We conducted a national cohort study of 3 571 574 individuals born in Sweden in 1973-2008 who were followed for incidence of NHL through 2009 (ages 0-37 years). Detailed information on perinatal and family characteristics and NHL diagnoses were obtained from national birth and cancer registries. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between perinatal and family variables and NHL; P values are from two-sided tests., Results: There were 936 NHL case patients identified in 66.3 million person-years of follow-up. Independent risk factors for NHL included family history of NHL in either a sibling (adjusted HR = 9.84; 95% CI = 2.46 to 39.41; P = .001) or parent (adjusted HR = 2.36; 95% CI = 1.27 to 4.38; P = .007); high fetal growth (for ≥ 2 SDs relative to 0 to <1 SD from the mean: adjusted HR = 1.64; 95% CI = 1.19 to 2.25; P = .002); older maternal age (adjusted HR for each 5-year increment = 1.11; 95% CI = 1.04 to 1.19; P (trend) = .004); low birth order (adjusted HR for each increment of one birth = 0.91; 95% CI = 0.84 to 0.99; P (trend) = .02); and male sex (adjusted HR = 1.58; 95% CI = 1.38 to 1.80; P < .001). Male sex was associated with onset of NHL before 15 years of age but not with later-onset NHL, whereas the other risk factors did not vary by age at diagnosis. No association was found between gestational age at birth, twinning, paternal age, or parental education and NHL., Conclusion: In this large national cohort study, family history of NHL, high fetal growth, older maternal age, low birth order, and male sex were independent risk factors for NHL in early life.

The Kingdom of Saudi Arabia (KSA), similar to other countries in the Eastern Mediterranean, has been experiencing a recent rapid increase in the prevalence of chronic diseases and associated risk factors. To begin to take advantage of the chronic disease prevention and health promotion (CDPHP) knowledge available from other nations, researchers at a newly established University in the Qassim Province of the KSA have partnered with Stanford University in the United States of America. To ensure that CDPHP research and interventions are culturally relevant and appropriate, a participatory research approach has been adopted where local researchers are the target "community." Contextual challenges of conducting CDPHP research in the KSA, at the individual, social/cultural, organizational and environmental/policy levels, are identified, as well as examples of CDPHP intervention strategies that may be culturally appropriate at each level.

Previous studies have reported an association between preterm birth and elevated blood pressure in adolescence and young adulthood. These studies were based on single-day blood pressure measurements and had limited ability to estimate risk of hypertension measured over a longer period and across the full range of gestational ages. The authors conducted a national cohort study of all infants born in Sweden from 1973 through 1979 (n = 636,552), including 28,220 born preterm (<37 weeks), followed to ages 25.5-37.0 years to determine whether individuals born preterm were more likely to be prescribed antihypertensive medications in 2005-2009 than those born full term. Antihypertensive medication data were obtained from all outpatient and inpatient pharmacies throughout Sweden. Young adults who were born preterm had an increased relative rate of antihypertensive medication prescription that increased monotonically by earlier gestational age and that was independent of fetal growth. The adjusted odds ratio for ≥1 antihypertensive medications/year ranged from 1.25 (95% confidence interval: 1.12, 1.39) for those born near term (35-36 weeks) to 2.51 (95% confidence interval: 1.11, 5.68) for those born extremely preterm (23-27 weeks) relative to those born full term. These findings suggest that preterm birth is strongly associated with hypertension in young adulthood, including an increased risk among those born near term.

Background: Recent studies suggest an increased risk of adverse mental health outcomes among young adults who were born preterm. These studies have been based mainly on hospital data, thus missing large numbers of mental health problems that do not require inpatient treatment. We used national outpatient and inpatient pharmacy data to evaluate whether individuals who were born preterm were more likely to be prescribed psychiatric medications during young adulthood than individuals who were born full term., Methods: A national cohort of all infants born in Sweden from 1973 through 1979 [N = 635,933, including 28,799 who were born preterm (<37 weeks)] was followed to ages 25.5-34.0 years to determine whether psychotropic medications (antidepressants, antipsychotics, anxiolytics, hypnotics/sedatives and/or psychostimulants) were prescribed in 2005-06., Results: A trend of increasing rate of prescriptions for antipsychotics, antidepressants and hypnotics/sedatives in young adulthood was observed by earlier gestational age at birth. Young adults who were extremely preterm at birth (23-27 weeks) were 3.1 times more likely to be prescribed antipsychotics [95% confidence interval (CI) 1.66-5.93], 1.8 times more likely to be prescribed antidepressants (95% CI 1.26-2.64) and 1.8 times more likely to be prescribed hypnotics/sedatives (95% CI 1.15-2.96) than individuals who were full term at birth, after adjusting for potential confounders., Conclusions: This national cohort study, using outpatient and inpatient pharmacy data, suggests that preterm birth has important independent effects on mental health that extend at least into young adulthood.

The authors examined associations between neighborhood-level deprivation and cardiovascular disease-related health knowledge and behavior changes, as well as the estimated 12-year probability of experiencing a coronary heart disease event. Primary analyses included multilevel regression models among 8,197 women and men living in 82 neighborhoods in four northern California cities who were interviewed in one of five surveys conducted between 1979 and 1990. After controlling for age, gender, marital status, race/ethnicity, city, and time, the authors found that adults living in high-deprivation neighborhoods had significantly lower health knowledge and a higher probability of no positive behavior changes than did adults in moderately deprived neighborhoods (i.e., harmful effects). Conversely, those living in low-deprivation neighborhoods had significantly higher health knowledge and lower probabilities of no positive behavior changes and estimated risk of coronary heart disease (i.e., protective effects). The association between high neighborhood deprivation and no positive behavior changes remained statistically significant after additional adjustment for a composite measure of individual-level socioeconomic status. Associations with neighborhood deprivation did not vary by individual-level socioeconomic status. These results suggest that focusing exclusively on changing individuals' behaviors will have a limited effect unless contextual influences at the neighborhood level are also addressed.

In this article, we seek to confirm past studies that document increased levels of cardiovascular disease (CVD) risk factors among White men with lower educational attainment. Second, we include a population of Hispanic men (89% Mexican American) to examine the separate and interactive effects of ethnicity and education (our measure of socioeconomic status) on CVD risk factors. Third, we examine how education and ethnicity are related to receiving health messages from print media and interpersonal channels, with the hypothesis that less educated, higher CVD risk Hispanic and White men receive fewer messages than more educated men. Finally, we examine other psychosocial variables (e.g. knowledge, self-efficacy and motivation) that may help explain observed differences in CVD risk and health communication. The study sample included 2029 men, 25-64 years of age, from three population-based, cross-sectional surveys conducted from 1979 to 1990 as part of the Stanford Five-City Project. Hispanic and White men with lower educational attainment had higher levels of CVD risk factors, and received less health information from print media and interpersonal channels than Hispanic and White men with higher educational attainment. Furthermore, less educated men from both ethnic groups reported less CVD knowledge, lower self-efficacy and lower motivation to reduce CVD risk factors than higher educated men. These results highlight the need for effective intervention programs that target low educated Hispanic and White men to decrease their disproportionate risk of CVD.

In the past two decades several community intervention studies designed to lower the risk of cardiovascular disease in populations have been completed. These trials shared the rationale that the community approach was the best way to address the large population attributable risk of mild elevations of multiple risk factors, the interrelation of several health behaviors, and the potential efficiency of large-scale interventions not limited to the medical care system. These trials also shared several threats to internal validity, especially the small number of intervention units (usually cities) that could be studied. The purpose of this paper is to reflect on the lessons learned in one of the studies, the Stanford Five-City Project, which began in 1978. The anticipated advantages were observed, including the generalizability of the intervention components, the potential for amplification of interventions through diffusion in the community, and the efficiency of the mass media and other community programs for reaching the entire population. Numerous components of the intervention proved effective when evaluated individually, as was true in other community studies. However, the design limitations proved difficult to overcome, especially in the face of unexpectedly large, favorable risk factor changes in control sites. As a result, definitive conclusions about the overall effectiveness of the communitywide efforts were not always possible. Nevertheless, in aggregate, these studies support the effectiveness of communitywide health promotion, and investigators in the field should turn to different questions. The authors have learned how little they know of the determinants of population-level change and the characteristics that separate communities that change quickly in response to general health information from those that do not. Future studies in communities must elucidate these characteristics, while improving the effectiveness of educational interventions and expanding the role of environmental and health policy components of health promotion.

Although past studies have compared cigarette smoking patterns in Hispanics and whites, few have examined differences within sex and educational subgroups. Data are presented for 1,088 Hispanic women and men (89% Mexican-American origin) and pairwise matched white women and men (544 pairs), aged 25-74 years, who participated in population-based cross-sectional surveys in California in 1979-1990. Each pair was matched on age, sex, educational level, city of residence, and survey time period. There were large differences in smoking prevalence rates between Hispanic and white pairs with low educational attainment. White women and men with less than a high school education were approximately twice as likely to be current daily cigarette smokers as were similarly educated Hispanic women and men (46.1 vs. 20.6% for women and 52.7 vs. 30.1% for men). As the level of education increased, these ethnic differences in smoking decreased and became negligible among those who completed college. Virtually all low-educated white men (92.5%) and most low-educated white women (73.1%) were either current or former daily smokers. There were large ethnic differences in rates of smoking cessation advice from a physician; only 8.3% of low-educated Hispanic men who were current daily smokers had ever been advised by a physician to stop smoking, compared with 59.6% of low-educated white men. These data confirm ethnic differences in smoking behavior and identify the high smoking rates of white men and women with low educational attainment, thus delineating an often unrecognized group toward whom tobacco prevention and cessation activities should be directed.

Although past studies have compared health-related risk factors in Hispanics and whites, few studies have controlled for potential confounding from sociodemographic variables. Using data on men and women aged 25-74 years who responded to biennial cross-sectional surveys conducted in four diverse California cities from 1979 to 1990, the authors employed a matched-pairs design in which 756 Hispanic respondents were matched to 756 white respondents according to age, sex, educational level, city of residence, and time of survey. No significant differences between Hispanics and whites were found for any of the blood pressure indicators (systolic and diastolic blood pressure, prevalence of hypertension, and use of antihypertensive medication), caloric intake, total cholesterol, alcohol intake, or physical activity. The only variables for which Hispanics had higher levels of risk factors than whites were body mass index (weight (kg)/weight (m)2; 27.5 vs. 25.6, p < 0.001) and high density lipoprotein cholesterol (48.6 mg/dl vs. 50.1 mg/dl, p < 0.03). Whites, on the other hand, were significantly more likely to be current smokers than Hispanics (34.2% vs. 24.0%, p < 0.001) and, among smokers, to smoke a greater number of cigarettes per day (19.7 vs. 11.4 cigarettes/day, p < 0.001). Whites were also significantly more likely to have higher-fat diets, as measured by percentages of calories derived from total fat (37.6% vs. 35.1%, p < 0.04) and saturated fat (13.6% vs. 12.3%, p < 0.03). Examination of interactions indicated further risk factor differences by ethnicity across several sex, age, and educational subgroups.

The Stanford Five-City Project was initiated in 1978 to evaluate the effects of community-wide health education on coronary heart disease risk factors in two control (San Luis Obispo and Modesto) and two treatment (Monterey and Salinas) cities. This paper examines sex differences in the prevalence of smoking, hypercholesterolemia, and hypertension from the baseline survey in 1979-1980 through the conclusion of the intervention in 1985-1986. Four independent cross-sectional surveys (n = 1,713, 1,709, 1,848, and 1,768) and four repeated surveys of a cohort (n = 817) were conducted. This analysis presents findings separately for a younger age group (25-49 years) and an older age group (50-74 years). Smoking, hypercholesterolemia, and hypertension were more prevalent among younger men than younger women in both treatment and control cities. In general, this excess risk among younger men disappeared or reversed in the older age group. Over the 7-year study, the prevalence of hypertension and smoking decreased for both men and women in all surveys, the prevalence of hyper-cholesterolemia displayed no definite change, and male/female ratios of risk factor prevalence showed either no change or a slight decrease. This study confirms a higher prevalence of the three major risk factors for coronary heart disease among younger men, with the prevalence of hypercholesterolemia and, to a lesser extent, the prevalence of smoking becoming greater among women than men in the older age group and the prevalence of hypertension becoming equivalent.

This paper examines the effects of community-wide health education on diet-related knowledge and behavior and on plasma cholesterol levels during an experimental field study in medium-sized cities in northern California. Samples of the population aged 12-74 years were drawn at baseline and every 2 years thereafter to obtain four cross-sectional surveys; participants aged 25-74 years are included in this paper (n = 6,814 or about 425 per city per survey). The baseline sample was asked to return to three follow-up surveys, also 2 years apart, constituting the cohort survey sample (n = 777). Diet was assessed by 24-hour recalls. In the serial cross-sectional survey samples, nutritional knowledge increased over time in both men and women in all cities; among women, this increase was significantly greater in the treatment cities. Plasma cholesterol declined significantly only in men and in neither sex was there evidence of a larger decline in treatment than in control cities. Dietary saturated fat intake tended to decline, but not significantly in either sex, and there was no evidence of treatment impact. Dietary cholesterol intake declined in both sexes. Results in the cohort samples were similar, except plasma cholesterol levels were unchanged over time in men and increased in women, and dietary saturated fat intake declined significantly among women. Secular improvements in knowledge of nutrition and in dietary cholesterol intake occurred during the early 1980s in both men and women in these four cities, while there was less consistent improvement in dietary saturated fat intake. Only nutritional knowledge among women achieved greater improvement in treatment cities than in control cities. Continued and greater change in nutrition probably requires more sustained effort and broader methods, including changes in the food supply.

The Stanford Five-City Project was initiated in 1978 to evaluate the effects of a community-wide health education program on cardiovascular risk factors, including blood pressure. Two treatment cities received an education program, which used the mass media, various community-based programs, and health professionals, designed to encourage individuals to learn their blood pressure levels, stay in the care of a physician if hypertensive, achieve ideal weight, exercise regularly, and reduce dietary sodium. Physicians were encouraged to follow national hypertension treatment guidelines and were provided with a range of patient education materials. To evaluate the effect of the intervention on cardiovascular risk factors, four independent cross-sectional surveys of randomly selected households and four repeated surveys of a cohort were conducted in both treatment cities and in two of the three control cities. After 5-1/3 years of intervention, blood pressure in the treatment cities exhibited an overall decline of 7.4 and 5.5 mmHg systolic and 5.0 and 3.7 mmHg diastolic in the cohort and independent surveys, respectively. These declines produced net changes between the treatment and control cities ranging from -1.1 to -3.8 mmHg. While the magnitude of these changes is not large, the results are significant from a public health perspective because they reflect changes in the overall community.

This paper presents an analysis of self-reported stressors and blood pressure in a population of 1,428 San Francisco bus drivers surveyed from 1983 to 1985 as part of an occupational health study. To test the hypothesis of a positive association between psychosocial stressors and hypertension, the authors derived a stressor index from a survey instrument that assessed subjects' appraisal of work-related problems. A logistic regression analysis revealed an unexpected inverse association between the stressor index and hypertension that remained significant after adjustment for 12 potential confounding variables (standardized odds ratio = 0.84, p = 0.038). An analysis restricted to the 1,040 normotensive subjects, with mean blood pressure level as the outcome variable, also yielded inverse findings. To assess whether the results were specific to blood pressure, the authors repeated the multiple logistic analysis for gastrointestinal, respiratory, and musculoskeletal problems. In contrast to the inverse association found for hypertension, highly significant positive associations were found between the stressor index and these health problems. When prevalence of disease was examined by level of stressor score, a significant inverse gradient was observed for hypertension and significant positive gradients were observed for gastrointestinal, respiratory, and musculoskeletal problems (p values less than 0.001). An etiologic implication of these findings is that there may be a direct inverse association between subjective appraisal of stressors and blood pressure. A methodological implication is that subjective appraisal of stressors by persons with heightened blood pressure may be an invalid measure of objective, verifiable stressors.

This paper reports the results of a cross-sectional study conducted to evaluate the prevalence of hypertension in 1500 black and white male bus drivers from a large urban transit system in the US. Data for this study were compiled from the files of an occupational health clinic which conducts biennial medical examinations for drivers' license renewal. To test whether prevalence of hypertension was higher among bus drivers than among employed individuals in general, drivers were compared to three groups: individuals from both a national and local health survey and individuals undergoing baseline health examinations prior to employment as bus drivers. After adjustment for age and race, hypertension rates for bus drivers were significantly greater than rates for each of the three comparison groups. These findings support previous results from international studies of bus drivers suggesting that exposure to the occupation of driving a bus may carry increased health risk. This research has expanded into an on-going study which has the goals of clarifying the extent of hypertension in bus drivers and identifying specific behavioural and occupational factors that may be responsible for increased risk of cardiovascular disease.

In an extensive search of available literature, 22 epidemiological studies that have examined health risks of bus drivers were identified. These studies focus on three main disease categories: (1) cardiovascular disease, including hypertension, (2) gastrointestinal illnesses, including peptic ulcer and digestive problems, and (3) musculoskeletal problems including back and neck pain. The studies consistently report that bus drivers have higher raes of mortality, morbidity, and absence due to illness when compared to employees from a wide range of other occupational groups. Increased disease rates have been found for drivers regardless of the use of different research methodologies, measurement techniques and comparison groups. When evaluating the impact of bias on the estimates of risk, it appears likely that findings are conservative: strong systematic selective factors have probably favoured the elimination of those in poorer health both at the time of entry into and exit from the job of bus driving and other sources of bias have most likely caused underestimations of risk. Nevertheless, there remain questions that need careful assessment before firm conclusions can be made about whether increased disease rates result from driving a bus. Such questions, coupled with the consistent findings of heightened risk of disease, make urban bus drivers an appropriate and promising occupational group in which to study further the potential adverse effects of the work environment on employee health.

This study examines the extent to which a set of 10 demographic, behavioral, and medical risk factors explain black/white differences in hypertension. Data are from a cross-sectional examination of San Francisco transit drivers aged 25-65 years surveyed during 1983-1985 as part of an occupational health study. The inherent restriction of the study population to bus drivers and the further restriction to males in this population (764 blacks and 224 whites) controlled for factors related to occupation and sex. Control of 10 additional potential risk factors, including age, education, body mass index, smoking, and intake of caffeine and alcohol was possible in the analytic phase of the study. The unadjusted prevalence of hypertension (systolic blood pressure greater than or equal to 140 mmHg, diastolic blood pressure greater than or equal to 90 mmHg, or current use of antihypertensive medications) was 36.1 per cent for black males compared with 30.8 per cent for white males. The greatest difference in prevalence was observed for black males aged 55-64 years, for whom the prevalence was 46 per cent higher than for white males the same age. Despite higher rates of hypertension, blacks in all age groups exhibited lower levels of most major risk factors for hypertension. As a result, the independent effect of race on hypertension was increased rather than attenuated when the 10 covariables were taken into account (odds ratio of 1.27 in the unadjusted analysis, increasing to 1.54 in the adjusted, multivariate analysis). That this set of risk factors did not explain the higher rates of hypertension among blacks suggests that racial differences may arise from as yet unrecognized environmental and/or individual factors. The results also indicate that the association between race and blood pressure may have been underestimated in past studies that have relied on unadjusted analyses, in which negative confounding or masking effects of covariables have not been considered.