Lorraine G. Ogden

Long-Term Absolute Benefit of Lowering Blood Pressure in Hypertensive Patients According to the JNC VI Risk Stratification

Blood pressure (BP) levels alone have been traditionally used to make treatment decisions in patients with hypertension. The sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI) recently recommended that risk strata, in addition to BP levels, be considered in the treatment of hypertension. We estimated the absolute benefit associated with a 12 mm Hg reduction in systolic BP over 10 years according to the risk stratification system of JNC VI using data from the National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. The number-needed-to-treat to prevent a cardiovascular event/death or a death from all causes was reduced with increasing levels of baseline BP in each of the risk strata. In addition, the number-needed-to-treat was much smaller in persons with > or =1 additional major risk factor for cardiovascular disease (risk group B) and in those with a history of cardiovascular disease or target organ damage (risk group C) than in those without additional major risk factors for cardiovascular disease (risk group A). Specifically, the number-needed-to-treat to prevent a death from all causes in patients with a high-normal BP, stage 1 hypertension, or stage 2 or 3 hypertension was, respectively, 81, 60, and 23 for those in risk group A; 19, 16, and 9 for those in risk group B; and 14, 12, and 9 for those in risk group C. Our analysis indicated that the absolute benefits of antihypertensive therapy depended on BP as well as the presence or absence of additional cardiovascular disease risk factors and the presence or absence of preexisting clinical cardiovascular disease or target organ damage.

Dietary Intake of Folate and Risk of Stroke in US Men and Women NHANES I Epidemiologic Follow-Up Study

Background and Purpose— Few population-based studies have examined the relationship between dietary intake of folate and risk of stroke and cardiovascular disease (CVD). This study examines the association between dietary intake of folate and the subsequent risk of stroke and CVD. Methods— Study participants included 9764 US men and women aged 25 to 74 years who participated in the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study (NHEFS) and were free of CVD at baseline. Dietary intake of folate was assessed at baseline using a 24-hour dietary recall and calculated using ESHA software. Incidence data for stroke and CVD were obtained from medical records and death certificates. Results— Over an average of 19 years of follow-up, 926 incident stroke events and 3758 incident CVD events were documented. The relative risk (RR) was 0.79 (95% confidence interval [CI], 0.63 to 0.99, P =0.03 for trend) for incident stroke events and 0.86 (95% CI: 0.78 to 0.95, P <0.001 for trend) for incident CVD events in the highest quartile of dietary folate intake (median, 405.0 &mgr;g/day) compared with those in the lowest quartile (median, 99.0 &mgr;g/day), after adjustment for established cardiovascular risk factors and dietary factors. Conclusions— Our findings indicate an inverse relationship between dietary intake of folate and subsequent risk of stroke and CVD. Increasing dietary intake of folate from food sources may be an important approach to the prevention of CVD in the US population.

Dietary potassium intake and risk of stroke in US men and women: National Health and Nutrition Examination Survey I epidemiologic follow-up study.

Background and Purpose— The few prospective studies that have explored the association between dietary intake of potassium and risk of stroke have reported inconsistent findings. This study examines the relationship between dietary potassium intake and the risk of stroke in a representative sample of the US general population. Methods— Study participants included 9805 US men and women who participated in the first National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-Up Study. Dietary potassium and total energy intake were estimated at baseline by using a 24-hour dietary recall. Incidence data for stroke and coronary heart disease were obtained from medical records and death certificates. Results— Over an average of 19 years of follow up, 927 stroke events and 1847 coronary heart disease events were documented. Overall, stroke hazard was significantly different among quartiles of potassium intake (likelihood ratio P =0.03); however, a test of linear trend across quartiles did not reach a customary level of statistical significance (P =0.14). Participants consuming a low potassium diet at baseline (<34.6 mmol potassium per day) experienced a 28% higher hazard of stroke (hazard ratio 1.28, 95% CI 1.11 to 1.47;P <0.001) than other participants, after adjustment for established cardiovascular disease risk factors. Conclusions— These findings suggest that low dietary potassium intake is associated with an increased risk of stroke. However, the possibility that the association is due to residual confounding cannot be entirely ruled out in this observational study.

Dietary Intake of Folate and Risk of Stroke in US Men and Women

Background and Purpose— Few population-based studies have examined the relationship between dietary intake of folate and risk of stroke and cardiovascular disease (CVD). This study examines the association between dietary intake of folate and the subsequent risk of stroke and CVD. Methods— Study participants included 9764 US men and women aged 25 to 74 years who participated in the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study (NHEFS) and were free of CVD at baseline. Dietary intake of folate was assessed at baseline using a 24-hour dietary recall and calculated using ESHA software. Incidence data for stroke and CVD were obtained from medical records and death certificates. Results— Over an average of 19 years of follow-up, 926 incident stroke events and 3758 incident CVD events were documented. The relative risk (RR) was 0.79 (95% confidence interval [CI], 0.63 to 0.99, P =0.03 for trend) for incident stroke events and 0.86 (95% CI: 0.78 to 0.95, P <0.001 for trend) for incident CVD events in the highest quartile of dietary folate intake (median, 405.0 &mgr;g/day) compared with those in the lowest quartile (median, 99.0 &mgr;g/day), after adjustment for established cardiovascular risk factors and dietary factors. Conclusions— Our findings indicate an inverse relationship between dietary intake of folate and subsequent risk of stroke and CVD. Increasing dietary intake of folate from food sources may be an important approach to the prevention of CVD in the US population.

Dietary Intake of Folate and Risk of Stroke in US Men and Women: NHANES I Epidemiologic Follow-Up Study * Editorial Comment: NHANES I Epidemiologic Follow-Up Study

Background and Purpose— Few population-based studies have examined the relationship between dietary intake of folate and risk of stroke and cardiovascular disease (CVD). This study examines the association between dietary intake of folate and the subsequent risk of stroke and CVD. Methods— Study participants included 9764 US men and women aged 25 to 74 years who participated in the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study (NHEFS) and were free of CVD at baseline. Dietary intake of folate was assessed at baseline using a 24-hour dietary recall and calculated using ESHA software. Incidence data for stroke and CVD were obtained from medical records and death certificates. Results— Over an average of 19 years of follow-up, 926 incident stroke events and 3758 incident CVD events were documented. The relative risk (RR) was 0.79 (95% confidence interval [CI], 0.63 to 0.99, P =0.03 for trend) for incident stroke events and 0.86 (95% CI: 0.78 to 0.95, P <0.001 for trend) for incident CVD events in the highest quartile of dietary folate intake (median, 405.0 &mgr;g/day) compared with those in the lowest quartile (median, 99.0 &mgr;g/day), after adjustment for established cardiovascular risk factors and dietary factors. Conclusions— Our findings indicate an inverse relationship between dietary intake of folate and subsequent risk of stroke and CVD. Increasing dietary intake of folate from food sources may be an important approach to the prevention of CVD in the US population.

Dietary Potassium Intake and Risk of Stroke in US Men and Women : National Health and Nutrition Examination Survey I Epidemiologic Follow-Up Study Editorial Comment: National Health and Nutrition Examination Survey I Epidemiologic Follow-Up Study Potassium, Stroke, and the Bounds of Epidemiological Studies: National Health and Nutrition Examination Survey I Epidemiologic Follow-Up Study

Background and Purpose— The few prospective studies that have explored the association between dietary intake of potassium and risk of stroke have reported inconsistent findings. This study examines the relationship between dietary potassium intake and the risk of stroke in a representative sample of the US general population. Methods— Study participants included 9805 US men and women who participated in the first National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-Up Study. Dietary potassium and total energy intake were estimated at baseline by using a 24-hour dietary recall. Incidence data for stroke and coronary heart disease were obtained from medical records and death certificates. Results— Over an average of 19 years of follow up, 927 stroke events and 1847 coronary heart disease events were documented. Overall, stroke hazard was significantly different among quartiles of potassium intake (likelihood ratio P =0.03); however, a test of linear trend across quartiles did not reach a customary level of statistical significance (P =0.14). Participants consuming a low potassium diet at baseline (<34.6 mmol potassium per day) experienced a 28% higher hazard of stroke (hazard ratio 1.28, 95% CI 1.11 to 1.47;P <0.001) than other participants, after adjustment for established cardiovascular disease risk factors. Conclusions— These findings suggest that low dietary potassium intake is associated with an increased risk of stroke. However, the possibility that the association is due to residual confounding cannot be entirely ruled out in this observational study.

Dietary Potassium Intake and Risk of Stroke in US Men and Women

Background and Purpose— The few prospective studies that have explored the association between dietary intake of potassium and risk of stroke have reported inconsistent findings. This study examines the relationship between dietary potassium intake and the risk of stroke in a representative sample of the US general population. Methods— Study participants included 9805 US men and women who participated in the first National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-Up Study. Dietary potassium and total energy intake were estimated at baseline by using a 24-hour dietary recall. Incidence data for stroke and coronary heart disease were obtained from medical records and death certificates. Results— Over an average of 19 years of follow up, 927 stroke events and 1847 coronary heart disease events were documented. Overall, stroke hazard was significantly different among quartiles of potassium intake (likelihood ratio P =0.03); however, a test of linear trend across quartiles did not reach a customary level of statistical significance (P =0.14). Participants consuming a low potassium diet at baseline (<34.6 mmol potassium per day) experienced a 28% higher hazard of stroke (hazard ratio 1.28, 95% CI 1.11 to 1.47;P <0.001) than other participants, after adjustment for established cardiovascular disease risk factors. Conclusions— These findings suggest that low dietary potassium intake is associated with an increased risk of stroke. However, the possibility that the association is due to residual confounding cannot be entirely ruled out in this observational study.