Обзор американских кардиологических журналов за неделю (ссылки)

[Chevychelov]

Wrist circumference in obese children may predict CVD
Capizzi M. Circulation. 2011;123:1757-1762.

A manual measure of wrist circumference was more closely linked to insulin parameters than BMI in a cohort of overweight or obese children and adolescents, according to new study results published in Circulation.

The trial involved 477 overweight or obese children and adolescents aged 10.31 ± 2.80 years from Rome. Each participant’s wrist was manually measured. The researchers also evaluated standard deviation score BMI, fasting biochemical parameters and homeostasis model assessment of insulin resistance in the study population.

A subcohort of 51 randomly selected participants underwent a wrist MRI to assess transversal wrist area at the Lister tubercle level.

Wrist circumference was significantly linked with the parameters of insulin levels (β=0.34) and homeostasis model assessment of insulin resistance (β=0.35), according to the results (P<10-5 for both comparisons).

Standard deviation BMI score yielded a statistical association of β=0.12 with insulin levels and β=0.10 with homeostasis model assessment of insulin resistance (P≤.02 for both comparisons).

In the MRI cohort, the link between wrist circumference and insulin levels was further clarified. Wrist circumference was associated insulin levels or homeostasis model assessment of insulin levels in bone tissue-related areas (P≤.01 for both comparisons) but not in adipose tissue areas (P>.05). MRI explained 20% of the variances in insulin levels and 17% of the variances in homeostasis model assessment of insulin levels.

The researchers noted that excess fat is a key determinant of insulin resistance which representing the metabolic basis for developing future CVD. The aim of the study, they said, was to find a clinical marker of insulin resistance to identify young individuals at increased risk for CVD.

“Our findings suggest a close relationship among wrist circumference, its bone component, and insulin resistance in overweight/obese children and adolescents, opening new perspectives in the prediction of CVD,” the researchers wrote.
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Serum alpha-carotene inversely associated with death from CVD, all-causes
Li C. Arch Intern Med. 2011;171:507-515.

Increasing levels of serum alpha-carotene had an inverse association with rates of death due to CVD and all-cause mortality among participants of the Third National Health and Nutrition Examination Survey.

These findings help to elucidate the role of carotenoids on CVD, as previous research had primarily involved beta-carotene, according to study investigators.

The current analysis included 15,318 US adults aged at least 20 years from the NHANES III, which was conducted from 1988 to 1994. Patients were considered ineligible if they had a follow-up of 1 month or less, missing data on covariates or insufficient identifying information.

The study’s findings revealed a mean alpha-carotene concentration of 4.79 mcg/dL for the entire cohort (men, 4.22 mcg/dL; women, 5.31 mcg/dL). A statistically significant association was found between increasing serum alpha-carotene levels and lower CVD-related mortality (P=.007), which included ischemic heart disease (P=.21), stroke (P=.84), as well as other CVDs (P=.06).

Overall, increasing levels of serum alpha-carotene compared with those in the reference group (0-1 mcg/dL) resulted in a lower risk for death from all-causes: 2 to 3 mcg/dL (RR=0.77; 95% CI, 0.68-0.87), 4 to 5 mcg/dL (RR=0.73; 95% CI, 0.65-0.83), 6 to 8 mcg/dL (RR=0.66; 95% CI, 0.55-0.79) and at least 9 mcg/dL (RR=0.61; 95% CI, 0.51-0.73).

According to researchers, this inverse association was independent of demographic characteristics, lifestyle habits and traditional health risk factors.

“Our results, if replicated in other studies and populations, suggest a need for clinical research into the health benefits of serum alpha-carotene,” they said.
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Combined diet, exercise more beneficial in older obese adults than either intervention alone
Villareal DT. N Engl J Med. 2011;364:1218-1229.

A combination of weight loss and exercise significantly improved physical function of obese older adults vs. either intervention alone, according to 1-year, randomized trial data.

The trial included 107 participants who were aged at least 65 years and considered obese. They were randomly assigned to either a control group (n=27), a weight-management (diet; n=26) group, an exercise group (n=26), or a diet-plus-exercise (diet-exercise; n=28) group. Among these participants, 93 finished the study.

At 1 year, the researchers reported that the study’s primary outcome, the change in Physical Performance Test score, was higher, thus indicating better physical status in individuals from the diet-exercise group (21%) vs. either diet (12%) or exercise (15%) groups, although all three were better than the control group (1%; P<.001 for between group differences).

Similarly, peak oxygen consumption was better in the diet-exercise (increase of 17%) arm compared with diet (10%) or exercise (8%) participants, as were scores on the Functional Status Questionnaire with the diet-exercise arm vs. the diet arm (increase of 10% vs. 4%; P<.001). Conversely, the greatest decrease in body weight was documented in the diet arm compared with those in the diet-exercise group (10% vs. 9%; P=.67), whereas no decreases were found in either the control or exercise arms.

“Our findings suggest that weight loss alone or exercise alone improves physical function and ameliorates frailty in obese older adults; however, a combination of weight loss and regular exercise may provide greater improvement in physical function and amelioration of frailty than either intervention alone,” the researchers concluded. “Therefore, weight loss combined with regular exercise may be beneficial in helping obese older adults maintain their functional independence.”