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David R Jacobs

Publications and source records attributed to David R Jacobs.

At least 73 records · Page 4Linked to original sources

Causes and demographic, medical, lifestyle and psychosocial predictors of premature mortality: the CARDIA study.

We examined the 16-year mortality experience among participants in the baseline examination (1985-86) of the Coronary Artery Risk Development in Young Adults (CARDIA) Study, a U.S. cohort of 5115 urban adults initially 18-30 years old and balanced by sex and race (black and whites) in the USA. We observed 127 deaths (annual mortality of 0.15%). Compared to white women, the rate ratio (95% confidence interval) of all-cause mortality was 9.3 (4.4, 19.4) among black men, 5.3 (2.5, 11.4) among white men and 2.7 (1.2, 6.1) among black women. The predominant causes of death, which also differed greatly by sex-race, were AIDS (28% of deaths), homicide (16%), unintentional injury (10%), suicide (7%), cancer (7%) and coronary disease (7%). The significant baseline predictors of all-cause mortality in multivariate analysis were male sex, black race, diabetes, self-reported liver and kidney disease, current cigarette smoking and low social support. Two other factors, self-reported thyroid disease and high hostility, were significant predictors in analyses adjusted for age, sex and race. In conclusion, we found striking differences in the rates and underlying cause of death across sex-race groups and several independent predictors of young adult mortality that have major implications for preventive medicine and social policies.

Acquired Immunodeficiency Syndrome↗

Validation of a pre-coded food diary used among 13-year-olds: comparison of energy intake with energy expenditure.

OBJECTIVE: To validate energy intake (EI) estimated from pre-coded food diaries against energy expenditure (EE) measured with a validated position-and-movement monitor (ActiReg) in groups of 13-year-old Norwegian schoolchildren. DESIGN: Two studies were conducted. In study 1 the monitoring period was 4 days; participants recorded their food intake for four consecutive weekdays using food diaries and wore the ActiReg during the same period. In study 2 the monitoring period was 7 days; participants recorded their food intake for four consecutive days but wore the ActiReg for a whole week. SETTINGS: Participants were recruited from grade 8 in a school in and one outside Oslo (Norway). SUBJECTS: Forty-one and 31 participants from study 1 and 2, respectively, completed the study. RESULTS: The group average EI was 34% lower than the measured EE in study 1 and 24% lower in study 2. The width of the 95% confidence limits of agreement in a Bland-Altman plot for EI and EE varied from -0.2 MJ to 8.2 MJ in study 1 and from -2.3 MJ to 6.9 MJ in study 2. The Pearson correlation coefficients between reported energy intake and expenditure were 0.47 (P=0.002) in study 1 and 0.74 (P<0.001) in study 2. CONCLUSION: The data showed that there was substantial variability in the accuracy of the food diary at the individual level. Furthermore, the diary underestimated the average energy intake. The ability of the food diary to rank individuals according to energy intake was found to be good in one of the studies and moderate in the other.

Adolescent↗

Serum gamma-glutamyltransferase within its normal range predicts a chronic elevation of alanine aminotransferase: a four year follow-up study.

BACKGROUND: Previous epidemiological and experimental studies support the concept that serum gamma-glutamyltransferase (GGT) activity within its normal range is related to oxidative stress. Since oxidative stress plays a crucial role in the pathogenesis of various liver diseases, serum GGT may predict development of liver damage. METHODS: A total of 6,523 healthy male workers with normal alanine aminotransferase (ALT, <35 U/l) in a steel manufacturing company were followed for four years. Liver damage was defined as a chronic elevation of serum ALT (both 2001 and 2002). RESULTS: After adjusting for age, body mass index, alcohol consumption, cigarette smoking, exercise, and baseline value of ALT, in comparison with the group whose GGT level was <10 U/l, the adjusted relative risks for elevated ALT level among those with GGT levels 10-19, 20-29, 30-39, and over 40 U/l was 1.0, 2.5, 4.7, 7.4, and 12.0, respectively (P for trend <0.01). More importantly, this association was similarly observed even among non-drinkers; the corresponding relative risks were 1.0, 1.8, 3.8, 5.6, and 6.2 (P for trend <0.01). However baseline ALT did not predict abnormal GGT level four years later. CONCLUSION: Serum GGT levels within normal range predict incidence of chronic elevation of ALT. Oxidative stress might explain this relationship.

Adult↗

Iron, zinc, and alcohol consumption and mortality from cardiovascular diseases: the Iowa Women's Health Study.

BACKGROUND: The relation between iron status and atherosclerosis has long been a topic of debate. OBJECTIVE: We examined associations of cardiovascular disease (CVD) mortality with dietary intakes of iron (a possible prooxidant), zinc (a possible antioxidant), and alcohol (a disruptor of iron homeostasis). DESIGN: Postmenopausal women (n = 34 492) aged 55-69 y at baseline, who completed a food-frequency questionnaire, were followed for CVD mortality over 15 y. RESULTS: Among women who consumed >/=10 g alcohol/d, after adjustment for CVD risk factors in a model that contained dietary heme iron, nonheme iron, and zinc intakes, dietary heme iron showed a positive association, dietary nonheme iron showed a U-shaped association, and dietary zinc showed an inverse association with CVD mortality. For example, the relative risks (RRs) for categories of dietary heme iron were 1.0, 1.46, 1.52, 1.73, and 2.47 (P for trend = 0.04); corresponding RRs for dietary nonheme iron were 1.0, 0.93, 0.63, 0.83, and 1.20 (P for quadratic term = 0.02). The corresponding RRs for dietary zinc were 1.0, 0.61, 0.59, 0.57, and 0.37 (P for trend = 0.07). In an analysis restricted to those who consumed >/=30 g alcohol/d, the risk gradients strengthened. CONCLUSIONS: Our results suggest that a higher intake of heme iron might be harmful, whereas a higher intake of zinc might be beneficial in relation to CVD mortality in the presence of a trigger that can disturb iron homeostasis, such as alcohol consumption.

Aged↗

Associations of plant food, dairy product, and meat intakes with 15-y incidence of elevated blood pressure in young black and white adults: the Coronary Artery Risk Development in Young Adults (CARDIA) Study.

BACKGROUND: Consumption of plant foods and dairy and meat products may moderate increases in blood pressure. OBJECTIVE: The objective was to evaluate associations of dietary intake with the 15-y incidence of elevated blood pressure (EBP; ie, incident systolic BP >or= 130 mm Hg, diastolic BP >or= 85 mm Hg, or use of antihypertensive medication). DESIGN: Proportional hazards regression was used to evaluate relations of dietary intake at years 0 and 7 with the 15-y incidence of EBP in the Coronary Artery Risk Development in Young Adults (CARDIA) Study of 4304 participants aged 18-30 y at baseline. RESULTS: EBP incidence varied from 12% in white women to 33% in black men. Plant food intake (whole grains, refined grains, fruit, vegetables, nuts, or legumes) was inversely related to EBP after adjustment for age, sex, race, center, energy intake, cardiovascular disease risk factors, and other potential confounding factors. Compared with quintile 1, the relative hazards of EBP for quintiles 2-5 of plant food intake were 0.83 (95% CI: 0.68, 1.01), 0.83 (0.67, 1.02), 0.82 (0.65, 1.03), and 0.64 (0.53, 0.90), respectively; P for trend = 0.01. Dairy intake was not related to EBP (P for trend = 0.06), and positive dose-response relations for EBP were observed across increasing quintiles of meat intake (P for trend = 0.004). In subgroup analyses, risk of EBP was positively associated with red and processed meat intake, whereas it was inversely associated with intakes of whole grain, fruit, nuts, and milk. Adjustment for intermediary factors in the causal pathway attenuated these relations. CONCLUSION: These findings are consistent with a beneficial effect of plant food intake and an adverse effect of meat intake on blood pressure.

Adolescent↗

Neighbourhood characteristics, individual level socioeconomic factors, and depressive symptoms in young adults: the CARDIA study.

STUDY OBJECTIVE: To investigate the relation between neighbourhood socioeconomic and ethnic characteristics with depressive symptoms in a population based sample. DESIGN: Cross sectional data from the CARDIA study, including the Center for Epidemiological Studies depression scale score (CES-D). Neighbourhoods were 1990 US census blocks of 1000 people; six census variables reflecting wealth/income, education, and occupation investigated separately and as a summary score; neighbourhood racial composition (percentage white and black) and individual level income and education were also examined. SETTING: Participants recruited in 1985/86 from community lists in Birmingham, AL; Chicago, IL; Minneapolis MN; from a health plan in Oakland, CA. PARTICIPANTS: 3437 adults aged 28-40 years in 1995/96: 24% white men, 27% white women, 20% black men, 29% black women. MAIN RESULTS: For each race-sex group, CES-D was inversely related to neighbourhood score and individual income and education. Associations of neighbourhood score with CES-D became weak and inconsistent after adjusting for individual level factors; personal income remained strongly and inversely associated with CES-D. Age adjusted mean differences (standard errors) in CES-D between the lowest and highest income categories were 3.41 (0.62) for white men, 4.57 (0.64) for white women, 5.80 (0.87) for black men, and 5.74 (0.83) for black women. For both black and white participants, CES-D was associated negatively with percentage of white people and positively with percentage of black people in their census block, before, but not after, adjustment for individual and neighbourhood socioeconomic variables. CONCLUSIONS: Neither neighbourhood socioeconomic characteristics nor ethnic density were consistently related to depressive symptoms once individual socioeconomic characteristics were taken into account.

Adult↗

Calcified coronary artery plaque measurement with cardiac CT in population-based studies: standardized protocol of Multi-Ethnic Study of Atherosclerosis (MESA) and Coronary Artery Risk Development in Young Adults (CARDIA) study.

Calcified coronary artery plaque, measured at cardiac computed tomography (CT), is a predictor of cardiovascular disease and may play an increasing role in cardiovascular disease risk assessment. The Multi-Ethnic Study of Atherosclerosis (MESA) and the Coronary Artery Risk Development in Young Adults (CARDIA) study of the National Heart, Lung, and Blood Institute are population-based studies in which calcified coronary artery plaque was measured with electron-beam and multi-detector row CT and a standardized protocol in 6814 (MESA) and 3044 (CARDIA study) participants. The studies were approved by the appropriate institutional review board from the study site or agency, and written informed consent was obtained from each participant. Participation in the CT examination was high, image quality was good, and agreement for the presence of calcified plaque was high (kappa = 0.92, MESA; kappa = 0.77, CARDIA study). Extremely high agreement was observed between and within CT image analysts for the presence (kappa > 0.90, all) and amount (intraclass correlation coefficients, >0.99) of calcified plaque. Measurement of calcified coronary artery plaque with cardiac CT is well accepted by participants and can be implemented with consistently high-quality results with a standardized protocol and trained personnel. If predictive value of calcified coronary artery plaque for cardiovascular events proves sufficient to justify screening a segment of the population, then a standardized cardiac CT protocol is feasible and will provide reproducible results for health care providers and the public.

Adult↗

Interaction among heme iron, zinc, and supplemental vitamin C intake on the risk of lung cancer: Iowa Women's Health Study.

Redox-active iron present at physiological levels in the pulmonary epithelial lining fluid may lead to damage of lung tissue under some circumstances. For example, factors that increase potential for oxidative stress, such as higher intake of heme iron or higher intake of vitamin C in the presence of high intake of iron, might increase the risk of lung cancer, whereas higher intake of the antioxidant zinc might decrease that risk. During 16 yr of follow-up, 34,708 postmenopausal women, aged 55-69 yr at baseline who completed a food-frequency questionnaire for the Iowa Women's Health Study, were followed for 700 incident lung cancers. When subjects were stratified by intake of vitamin C supplements, among women who took vitamin C supplements of >500 mg/day, after adjusting for age, total energy intake, cigarette smoking, alcohol consumption, and dietary zinc or dietary heme iron intake, relative risks across categories of dietary heme iron intake were 1.0, 0.85, 0.93, 1.32, 1.70, and 3.77 (P for trend = 0.05; P for interaction = 0.08), whereas corresponding figures for dietary zinc intake were 1.0, 1.15, 0.71, 0.84, 0.61, and 0.11 (P for trend = 0.12; P for interaction = 0.04). The strength of the associations of heme iron and zinc intake with lung cancer appeared to be stronger with increasing levels of vitamin C supplement intake. Our results suggest that high dietary heme iron intake may increase the risk of lung cancer, whereas high dietary zinc may decrease the risk of lung cancer among postmenopausal women who consume high-dose vitamin C supplements. This finding may be of particular importance to smokers, for whom vitamin C supplementation is a common recommendation.

Aged↗

A longitudinal study of physical activity and heart rate recovery: CARDIA, 1987-1993.

PURPOSE: Autonomic nervous system function may be a mechanism by which frequent physical activity is associated with better coronary heart disease outcomes. In a diverse, population-based sample, we tested whether physical activity participation was associated with higher parasympathetic function. METHODS: Participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study underwent symptom-limited graded exercise testing at baseline (1985-1986; N=3446) and at 7 yr follow-up (N=1627). Heart rate recovery (HRR), the difference between maximum heart rate (HR) and HR 2 min after test cessation, was used to estimate parasympathetic activity. RESULTS: Participants who self-reported in the highest tertile of total physical activity (the sum of moderate- and heavy-intensity activities) had significantly faster HRR than participants in the lowest tertile (45.1 vs 41.8 beats.min, P<0.01), and the odds of having abnormal HRR (<or=22 beats.min) were 1.9 (95% confidence interval: 1.1, 3.4) times greater in the lowest versus the highest tertile after adjustment for age, race, gender, body mass index, smoking status, and diastolic blood pressure. Findings were consistent across strata of covariates. On average, HRR declined 2.5 beats.min over 7 yr. HRR declined the least among participants whose physical activity increased (-1.3 beats.min) or remained stable (-1.8 beats.min), compared with participants whose physical activity decreased (-3.6 beats.min; P<0.01 vs increase or stable). CONCLUSIONS: In this diverse, population-based sample, physical activity was associated with faster HRR from an exercise treadmill test. Regular physical activity may blunt age-related declines in autonomic nervous system function.

Adult↗

Relation of C-reactive protein to insulin resistance and cardiovascular risk factors in youth.

OBJECTIVE: Insulin resistance and C-reactive protein (CRP) levels are strongly correlated in adults. This study explored the relationship in youth. RESEARCH DESIGN AND METHODS: Associations between CRP levels, cardiovascular risk, and insulin resistance measured by the euglycemic clamp were investigated in 342 healthy Minneapolis youth. RESULTS: There was no difference in mean CRP levels among boys (n = 189, CRP 1.10 +/- 0.46 mg/l) and girls (n = 153, CRP 1.16 +/- 0.63 mg/l; P = 0.32). There was also no difference between CRP and Tanner stage. CRP, adjusted for BMI, was significantly greater in black subjects compared with white subjects (P = 0.03). CRP was strongly related to adiposity in both girls and boys. CRP levels were related to fasting insulin levels (r = 0.16, P = 0.003) but this association was not significant after adjustment for BMI (r = 0.07, P = 0.21). Similarly, M, the euglycemic clamp measurement of insulin sensitivity, was significantly related to CRP levels (r = -0.13, P = 0.02) but not when M was normalized to lean body mass (M(lbm)) (r = -0.10, P = 0.09). There was a significant inverse correlation between M(lbm) and CRP quartiles, which disappeared after adjustment for BMI. There was no significant association between CRP levels and lipids, blood pressure, physical activity, or left ventricular mass. CONCLUSIONS: In contrast to adult subjects, after adjustment for adiposity, CRP levels in children age 10-16 years were not significantly associated with insulin resistance or with other factors comprising the metabolic syndrome. This is consistent with the concept that insulin resistance may precede the development of CRP elevation in the evolution of the metabolic syndrome.

Adolescent↗

Diabetes mellitus and subsite-specific colorectal cancer risks in the Iowa Women's Health Study.

OBJECTIVE: Controversy remains regarding the association between type 2 diabetes mellitus (DM) and colorectal cancer (CRC) risk. To clarify and extend the existing data, we prospectively evaluated the association between self-reported type 2 DM (onset at >30 years of age) and incident CRC, overall and by anatomic subsite, among postmenopausal women in the Iowa Women's Health Study (n = 35,230). METHODS: After 14 years of follow-up, a total of 870 incident CRC cases were identified through annual linkage to the Iowa Cancer Registry. DM was analyzed as reported at baseline and as a time-dependent variable using information obtained during follow-up. CRC risks were estimated using Cox proportional hazards regression models. RESULTS: After adjusting for age, body mass index and other potential confounding variables, the relative risk (RR) for women with DM versus women without DM was modestly increased at 1.4 [95% confidence interval (95% CI), 1.1-1.8]. By anatomic subsite, the RR for proximal colon cancer was statistically significantly increased (RR, 1.9; 95% CI, 1.3-2.6), whereas the RRs for distal colon (RR, 1.1; 95% CI, 0.6-1.8) and rectal cancer (RR, 0.8; 95% CI, 0.4-1.6) were not statistically different from unity. Analyses that included DM ascertained at baseline and follow-up yielded similar results. CONCLUSION: In this large, prospective study of postmenopausal women, the association between DM and incident CRC was found to be subsite specific. If confirmed by others, this finding implies that CRC prevention strategies among type 2 DM patients should include examination of the proximal colon.

Age of Onset↗

Plasma F2-isoprostanes and coronary artery calcification: the CARDIA Study.

BACKGROUND: Oxidation of lipids in lipoproteins and cells may initiate and enhance the early development of cardiovascular disease. METHOD AND RESULTS: We assayed F(2)-isoprostanes, oxidation products of arachidonic acid, by gas chromatography-mass spectrometry in a biracial cohort of 2850 young healthy adult men and women. Coronary artery calcification (CAC), a component of coronary artery atherosclerosis, was detectable in 10% of the cohort and appeared to be in its initial stages (Agatston scores <20 in 47% and <100 in 83% of CAC-positive participants). After adjusting for sex, clinical site, age, and race, the presence of any CAC was 24% more likely among those with high vs low concentrations of F(2)-isoprostanes [odds ratio (OR) = 1.24 per 92.2 pmol/L (32.7 ng/L; 1 SD of F(2)-isoprostanes); 95% confidence interval (CI), 1.09-1.41]. The OR was only slightly attenuated [1.18 per 92.2 pmol/L (32.7 ng/L); CI, 1.02-1.38] after further adjustment for body mass index, smoking, serum lipids, C-reactive protein, antioxidant supplementation use, diabetes, and blood pressure. As a continuous variable, the Agatston score increased by 6.9% per 92.2 pmol/L (32.7 ng/L) of F(2)-isoprostane concentration (P <0.01). Whereas CAC prevalence was lower in women than men, mean (SD), F(2)-isoprostanes were higher in women {190 (108.9) pmol/L [67.4 (38.6) ng/L]} than in men {140.4 (55.6) pmol/L [49.8 (19.7) ng/L]}. Nevertheless, F(2)-isoprostanes were associated with an increased risk of CAC in both sexes. CONCLUSION: This association between increased concentrations of circulating F(2)-isoprostanes and CAC in young healthy adults supports the hypothesis that oxidative damage is involved in the early development of atherosclerosis.

Adolescent↗

Association of lipoprotein-associated phospholipase A2 mass and activity with calcified coronary plaque in young adults: the CARDIA study.

OBJECTIVE: To examine the association of lipoprotein-associated phospholipase A2 (Lp-PLA2) mass and activity with calcified coronary plaque in young adults. METHODS AND RESULTS: Nested case-control study among CARDIA participants at the year 15 examination (2000 to 2001, 33 to 45 years old). Cases (n=266) were those with and controls (n=266) those without evidence of calcified coronary plaque by computed tomography matched 1:1 on sex and race. Lp-PLA2 mass and activity were significantly higher in cases (296+/-101 ng/mL and 36.4+/-12.3 nmol/mL per minute) than in controls (267+/-80 ng/mL and 32.9+/-11.8 nmol/mL per minute). In age-adjusted conditional logistic regression, the odds ratio (OR) of calcified coronary plaque per 1 standard deviation (SD) increment was 1.40 (95% CI, 1.17 to 1.67) and 1.39 (95% CI, 1.14 to 1.70) for Lp-PLA2 mass and activity, respectively. After adjusting for multiple covariates including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides, and C-reactive protein, a statistically significant association remained for Lp-PLA2 mass (OR, 1.28; 95% CI, 1.03 to 1.60) but not for activity (OR, 1.09; 95% CI, 0.84 to 1.42). No evidence was found for interaction between Lp-PLA2 mass or activity with LDL-C as predictors of calcified coronary plaque. CONCLUSIONS: An independent association of Lp-PLA2 mass with calcified coronary plaque existed in young adults. Therefore, Lp-PLA2 mass may be a useful marker of subclinical cardiovascular risk.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗

Is serum gamma-glutamyltransferase inversely associated with serum antioxidants as a marker of oxidative stress?

A series of studies in black and white women and men have suggested that serum gamma-glutamyltransferase (GGT) within its normal range might be an early marker of oxidative stress. If serum GGT is a marker of oxidative stress, it might have important implications both clinically and epidemiologically because measurement of serum GGT is easy, reliable, and not expensive. We examined the cross-sectional association between deciles of serum GGT and concentrations of serum antioxidants among 9083 adult participants in the third U.S. National Health and Nutrition Examination Survey. After adjustment for race, sex, age, and total cholesterol, serum concentration of GGT across all deciles was inversely associated with serum concentrations of alpha-carotene, beta-carotene, beta-cryptoxanthin, zeaxanthin/lutein, lycopene, and vitamin C (p for trend <.01, respectively). Vitamin E was not associated with serum GGT. All these associations were not materially different after additional adjustment for total energy intake, body mass index, smoking status, smoking amount, alcohol intake, and exercise. These associations were similarly observed among most subgroups. In conclusion, the current and previous studies strongly suggest that serum GGT level within its normal range may be an early marker of oxidative stress.

Alanine Transaminase↗

Gender differences in the relationship between periodontal disease, tooth loss, and atherosclerosis.

BACKGROUND AND PURPOSE: Males carry a disproportionate burden of cardiovascular disease. Because males also bear a higher burden of periodontal disease, we investigated the existence of gender differences in the postulated relationship between periodontal infections, tooth loss, and subclinical atherosclerosis. METHODS: A total of 1710 randomly enrolled participants between the ages of 45 and 75 with no history of myocardial infarction or stroke received a clinical periodontal examination, carotid scan using high-resolution B-mode ultrasound, and extensive measurements for conventional cardiovascular risk factors (age, education, smoking, alcohol, body mass index, diabetes, systolic blood pressure, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, and triglycerides) as well as markers of healthy lifestyle and social network. RESULTS: In both genders, measures of current and long-term periodontitis worsened as tooth loss increased. In males but not females, an approximately 10% difference in carotid artery plaque prevalence was observed between the lowest and highest tertiles of tooth loss (P<0.05) and long-term periodontitis (P=0.05) after multivariate adjustment. Similar patterns were observed for intima-media thickness. The influence of gender on carotid artery plaque prevalence was most evident among the younger age group (<59 years). Between genders, carotid plaque prevalence differed by 10%, 15%, and 25% across increasing levels of tooth loss, and by 5%, 15%, and 25% across increasing levels of long-term periodontitis. CONCLUSIONS: Our data suggest that tooth loss and long-term periodontitis are related to subclinical atherosclerosis in men but not women. Gender variations in cardiovascular morbidity or mortality may be explained partly by the differential contributions of novel risk factors across genders.

Aged↗

[Consumption of whole grain foods and chronic disease].

BACKGROUND: We summarise evidence concerning the health effects of whole grain intake, as well as implications for Norway. All forms of whole grain products contain both the bran and the germ, which are rich in nutrients, in addition to the starch-rich endosperm. However, refined grain consists only of the endosperm, which contains far fewer nutrients. MATERIAL AND METHODS: Review of published epidemiologic and food consumption data concerning grain intake. RESULTS: Recent epidemiologic investigations have found that whole grain intake is associated with reduced risk of several chronic diseases, especially cardiovascular diseases and diabetes. For example, the follow-up data of the cardiovascular disease study in Norwegian counties carried out during 1977-83 showed an inverse relationship between total mortality rates and eating whole grain bread. The United States Department of Agriculture and the Food and Drug Administration have endorsed statements that whole grain products can have positive health effects. About four times as much whole grain food is eaten in Norway as in the United States. However, many refined grain breads have recently been introduced in Norway. INTERPRETATION: Norwegians should be encouraged to maintain or even increase their consumption of whole grain foods.

Cardiovascular Diseases↗