Increased abdominal adiposity has been linked to an increase in mortality in populations in which overweight and obesity are prevalent; it is unclear whether the same is true in relatively lean populations. In a prospective cohort study of 72 773 nonsmoking women enrolled in the Shanghai Women's Health Study, 95% of whom had a body mass index (calculated as weight in kilograms divided by height in meters squared) less than 30. Zhang et al found that measured waist-hip ratio was positively associated with mortality, and the positive association was more evident in women with a lower body mass index. The authors conclude that abdominal adiposity predicts mortality risk, particularly for nonobese women.
See page 886
This study examines mortality and morbidity in a representative sample of elderly persons newly diagnosed as having type 2 diabetes mellitus. Using longitudinal data for a 12-year period, Bethel et al compared rates of adverse outcomes among persons diagnosed as having diabetes in 1994 with a control group throughout the period. Outcome measures were death, nephropathy, retinopathy, lower extremity, cardiovascular, and cerebrovascular complications. The diabetes group had an excess mortality of 9.2% by year 11 compared with the control group. There was a higher prevalence and incidence of microvascular and macrovascular complications compared with the controls. Patients with diabetes were at increased risk for lower extremity and cardiovascular complications.
See page 921
In this study by Marcus et al, 249 sedentary adults were randomized to 1 of the following 3 physical activity interventions: (1) Internet intervention motivationally tailored to the individual (tailored Internet); (2) print intervention motivationally tailored to the individual (tailored print; shown to be effective previously); and (3) 6 researcher-selected Web sites currently available to the public (standard Internet). At 6 months, the tailored Internet arm reported a median of 120.0 minutes of physical activity per week; the tailored print arm, 112.5 minutes per week; and the standard Internet arm, 90.0 minutes per week (P = .15). At 12 months, the median physical activity minutes per week were 90.0, 90.0, and 80.0 for the tailored Internet, tailored print, and standard Internet arms, respectively (P = .74). The results indicated no significant differences between the 3 arms. Because the use of the Internet was not different from the print-based intervention, this provides evidence that different channels of delivery can provide equally effective results.
See page 944
Schulze et al used dietary data collected in a large prospective study to assess the association between fiber and magnesium intake and risk of type 2 diabetes. During 7 years of follow-up, the authors found that higher intake of fiber from cereals, but not from fruit or vegetables, was associated with lower risk of type 2 diabetes. The authors also summarized all existing prospective studies by meta-analysis, confirming these associations. Although magnesium intake was not associated with diabetes risk in their cohort, the authors observed a lower risk with high magnesium intake in a meta-analysis of existing studies.
See page 956
Gammage et al performed a community-based study of 5860 subjects 60 years and older and examined associations between tests of thyroid function and the presence of atrial fibrillation (AF) on resting electrocardiogram. There was a higher prevalence of AF in those with subclinical hyperthyroidism (low serum thyrotropin [TSH] with normal serum free thyroxine [T4] levels) than in euthyroid subjects (with normal serum TSH levels). Median serum free T4 concentration was higher in those with AF than in those without and was higher in those with AF even when analysis was confined to euthyroid subjects. Furthermore, serum free T4 concentration was independently associated with the finding of AF on electrocardiogram, alongside the expected associations of AF with male sex and increasing age. These findings suggest that minor perturbations of thyroid status, even within the reference range, may have important pathophysiological consequences.
See page 928
In This Issue of Archives of Internal Medicine. Arch Intern Med. 2007;167(9):871. doi:10.1001/archinte.167.9.871