Shana L. Palla

Prevalence of Cardiovascular Disease Risk Factors in U.S. Children and Adolescents With Diabetes The SEARCH for Diabetes in Youth Study

OBJECTIVE—The purpose of this study was to determine the prevalence and correlates of selected cardiovascular disease (CVD) risk factors among youth aged <20 years with diabetes. RESEARCH DESIGN AND METHODS—The analysis included 1,083 girls and 1,013 boys examined as part of the SEARCH for Diabetes in Youth study, a multicenter, population-based study of youth 0–19 years of age with diabetes. Diabetes type was determined by a biochemical algorithm based on diabetes antibodies and fasting C-peptide level. CVD risk factors were defined as follows: HDL cholesterol <40 mg/dl; age- and sex-specific waist circumference >90th percentile; systolic or diastolic blood pressure >90th percentile for age, sex, and height or taking medication for high blood pressure; and triglycerides >110 mg/dl. RESULTS—The prevalence of having at least two CVD risk factors was 21%. The prevalence was 7% among children aged 3–9 years and 25% in youth aged 10–19 years (P < 0.0001), 23% among girls and 19% in boys (P = 0.04), 68% in American Indians, 37% in Asian/Pacific Islanders, 32% in African Americans, 35% in Hispanics, and 16% in non-Hispanic whites (P < 0.0001). At least two CVD risk factors were present in 92% of youth with type 2 and 14% of those with type 1A diabetes (P < 0.0001). In multivariate analyses, age, race/ethnicity, and diabetes type were independently associated with the odds of having at least two CVD risk factors (P < 0.0001). CONCLUSIONS—Many youth with diabetes have multiple CVD risk factors. Recommendations for weight, lipid, and blood pressure control in youth with diabetes need to be followed to prevent or delay the development of CVD as these youngsters mature.

Prevalence of nutrition and exercise counseling for patients with hypertension. United States, 1999 to 2000.

AbstractOBJECTIVE: To evaluate the prevalence of nutrition and exercise counseling for patients with hypertension. DESIGN: Cross-sectional survey data from the National Ambulatory Medical Care Survey (NAMCS) and the National Hospital Ambulatory Medical Care Survey (NHAMCS) for 1999 and 2000. SETTING: Office-based physician practices and hospital outpatient departments. PATIENTS/PARTICIPANTS: Patients age 18 or older with a diagnosis of hypertension. MEASUREMENTS AND MAIN RESULTS: In 1999 and 2000, over 137 million patient encounters had a diagnosis of hypertension. Nutrition and exercise counseling were provided at 35% and 26% of visits, respectively. Patients older than 74 received the least nutrition (28%) and exercise (18%) counseling. Asians and Hispanics were more likely to undergo any lifestyle counseling, while non-Hispanic whites received the least exercise and nutrition counseling. Patients with 2 cardiovascular comorbidities were counseled for diet (53%) and exercise (32%) more than those with 1 (44% and 31%) or none (30% and 23%; P≤.001 and P≤.001). The encounters in the NAMCS had higher rates of counseling than those in the NHAMCS. There were no significant differences in counseling rates with respect to gender, geographic region, severity of hypertension, or physician specialty. CONCLUSIONS: While there were significant differences in counseling rates with respect to age, race, comorbidity, and survey cohort, counseling for therapeutic lifestyle changes for patients with hypertension was uniformly suboptimal. Physicians need to recognize the importance of nonpharmacologic treatment in hypertension.

Positive association between mammographic breast density and bone mineral density in the Postmenopausal Estrogen/Progestin Interventions Study

IntroductionMammographic breast density is a strong independent risk factor for breast cancer. We hypothesized that demonstration of an association between mammographic breast density and bone mineral density (BMD) would suggest a unifying underlying mechanism influencing both breast density and BMD.MethodsIn a cross-sectional analysis of baseline data from the Postmenopausal Estrogen/Progestin Interventions Study (PEPI), participants were aged 45 to 64 years and were at least 1 year postmenopausal. Mammographic breast density (percentage of the breast composed of dense tissue), the outcome, was assessed with a computer-assisted percentage-density method. BMD, the primary predictor, was measured with dual-energy X-ray absorptiometry. Women quitting menopausal hormone therapy to join PEPI were designated recent hormone users.ResultsThe mean age of the 594 women was 56 years. The average time since menopause was 5.6 years. After adjustment for age, body mass index, and cigarette smoking, in women who were not recent hormone users before trial enrollment (n = 415), mammographic density was positively associated with total hip (P = 0.04) and lumbar (P = 0.08) BMD. Mammographic density of recent hormone users (n = 171) was not significantly related to either total hip (P = 0.51) or lumbar (P = 0.44) BMD. In participants who were not recent hormone users, mammographic density was 4% greater in the highest quartile of total hip BMD than in the lowest. In participants who were not recent hormone users, mammographic density was 5% greater in the highest quartile of lumbar spine BMD than in the lowest.ConclusionMammographic density and BMD are positively associated in women who have not recently used postmenopausal hormones. A unifying biological mechanism may link mammographic density and BMD. Recent exogenous postmenopausal hormone use may obscure the association between mammographic density and BMD by having a persistent effect on breast tissue.

Is there a positive association between mammographic density and bone mineral density? Authors' response

We read with interest the issues raised by Dite and coworkers [1] in their response to our recent research article [2], and we are pleased to address them. In their letter, Dite and colleagues present previously unpublished results that reveal no association between bone mineral density and mammographic density in female twins. Relevant information about the characteristics of the study participants, the methods of measuring mammographic density, and the timing of the mammograms in relation to the bone density assessment are not supplied. Differences in study samples, methods, and sample size could account for the difference between their results and ours. Dite and coworkers [1] posit several explanations for the apparent discrepancy between their study and ours. First, they suggest that our results were an artefact of our performance of multiple analyses. In fact, we performed only three regression analyses, and these analyses were based on clearly stipulated a priori hypotheses. We believe that a strict Bonferroni adjustment for multiple testing would have been overly conservative. Second, they argue that we might have been misled by outliers or influential points. However, we performed outlier analyses using the dfBeta approach [3], which confirmed that our results were not unduly influenced by extreme data points. It is impossible to rule out chance as a possible explanation for our results, but with a few exceptions this criticism applies to all studies. Finally, Dite and colleagues state that we might have assumed effect modification without testing for it. We tested for effect modification between recent use of hormone therapy and lumbar bone mineral density by adding an interaction term to the linear regression model that included age, body mass index, smoking, lumbar bone mineral density, and recent hormone therapy as covariates, and mammographic density as the outcome. The P value for the lumbar bone mineral density-recent hormone therapy interaction term was 0.0583 at the lumbar spine. Similar results were apparent at the hip (P = 0.094 for the interaction term). On this basis, we conclude that recent hormone therapy modifies the association between bone mineral density and mammographic density. We stand by our results and hope to elucidate what biologic factors may be responsible for the association between mammographic density and bone mineral density in our study.