Copyright 2007 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.2007
In a prospective cohort study of 46 755 men followed up for 16 years, 131 died from suicide. Higher body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) was related to a stepwise decline in suicide mortality rate, from 52 per 100 000 person-years among men with a BMI lower than 21 to 13 per 100 000 person-years among men with a BMI of 30 or higher. The relative risk of suicide for each 1-unit increment in BMI was 0.89 (95% confidence interval, 0.84-0.95; P<.001). Neither height nor physical activity was associated with the risk of suicide. Analyses of mental health–related quality of life showed a similar positive relationship with BMI.
To determine whether N-terminal pro–B-type natriuretic peptide (NT-proBNP) can be used to detect asymptomatic ventricular dysfunction, Corteville et al measured NT-proBNP and performed echocardiography in 815 patients with coronary disease and no history of heart failure. Of the 815 participants, 68 (8%) had systolic dysfunction (left ventricular ejection fraction, ≤50%), and 78 (10%) had diastolic dysfunction. Likelihood ratios for detecting systolic or diastolic dysfunction were 0.28 for NT-proBNP concentrations lower than 100 pg/mL, 0.95 for concentrations between 100 and 500 pg/mL, and 4.1 for concentrations higher than 500 pg/mL. A test result lower than 100 pg/mL reduced the probability of ventricular dysfunction from a pretest probability of 18% to a posttest probability of 6%. Thus, NT-proBNP levels lower than 100 pg/mL effectively rule out ventricular dysfunction in patients with coronary disease and no history of heart failure.
Increased homocysteine levels are associated with venous thrombosis, but whether this relation is causal is unclear. The T-variant of the common methylenetetrahydrofolate (MTHFR) 677 C→T polymorphism mildly increases homocysteine levels and has therefore been a candidate risk factor for venous thrombosis. This study included 4375 patients and 4856 control subjects from the Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis (MEGA study), a population-based case-control study. MTHFR 677 C→T was not associated with the risk of venous thrombosis, and the narrow confidence interval excludes even a small effect (odds ratio [95% confidence interval], 0.99 [0.91-1.08] for the CT genotype and 0.94 [0.81-1.08] for the TT genotype). Therefore, mildly elevated homocysteine levels as a result of MTHFR 677TT do not seem to cause venous thrombosis. There is no rationale for measuring the MTHFR 677 C→T variant for clinical purposes.
Diets high in fiber are associated with lower levels of inflammation. This study compared the reduction in inflammation after 3 weeks in participants on a 30-g/d fiber-supplemented diet with those on a diet naturally high in fiber (30 g/d), using a randomized crossover intervention design in 35 adults. Mean C-reactive protein level was reduced 13.7% with the high-fiber diet and 18.1% with the supplemented diet (both P<.05). C-reactive protein level decreased 30% to 40% (P<.05) in the lean normotensive participants, but by only 8% to 13% (P>.05) in obese hypertensive participants. The results demonstrate that fiber intake near 30 g/d from a diet or supplement can reduce levels of C-reactive protein in certain individuals.
In this prospective cohort study, Terry et al examined cardiac risk factors, including the Framingham Risk Score (FRS) at examination cycle 1 and longitudinally in 1697 Framingham Heart Study (FHS) offspring members by the survival status of their parents, who were members of the original cohort of the FHS. The offspring participants were grouped according to whether neither, one, or both parents survived to age 85 years. For all factors studied, except body mass index, the authors observed statistically significant linear trends for lower offspring risk factor levels with increasing parental survival category. Longitudinally, offspring of parents who lived longer had lower risk of blood pressure and FRS progression. These findings suggest that individuals with long-lived parents have advantageous cardiovascular risk profiles in middle age compared with those whose parents died younger.
In This Issue of Archives of Internal Medicine. Arch Intern Med. 2007;167(5):427. doi:10.1001/archinte.167.5.427