Association of C-reactive protein with surrogate measures of insulin resistance among nondiabetic US from National Health and Nutrition Examination Survey 1999-2002

BACKGROUND: Increased C-reactive protein (CRP) concentration and insulin resistance (IR) are associated with increased rates of adverse cardiovascular events. We sought to examine the relationship of CRP with surrogate measures of IR among nondiabetic adults in the US. METHODS: We conducted analyses using data from the National Health and Nutrition Examination Survey 1999-2002. We analyzed a nationally representative sample of 2514 men and nonpregnant women age > or = 20 years who were non-Hispanic white, non-Hispanic black, or Mexican American. RESULTS: After adjustment for age, sex, race/ethnicity, smoking status, systolic blood pressure, and serum concentrations of HDL cholesterol, LDL cholesterol, and triglyceride, CRP was significantly associated with 10 IR measures (all P values <0.01). The strength of the association attenuated after further adjustment for waist circumference (change in adjusted regression coefficients ranging from 60.0% to 75.1%). The association of CRP with each IR surrogate was similar (standardized regression coefficient ranges from 0.06 to 0.09). The association of CRP (>3 vs <1 mg/L) with the homeostasis model for assessment of IR (> or = 75th vs <75th percentile) was statistically significant among people with a body mass index > or = 30 kg/m(2) (odds ratio, 2.6; 95% CI, 1.3-5.1) or with a body mass index <25 kg/m(2) (odds ratio, 2.5; 95% CI, 1.5-4.2). CONCLUSIONS: CRP was significantly associated with the surrogate measures of IR among nondiabetic adults. Obesity may play an important role in the association of CRP with IR in this nationally representative sample.     

Chronic Pain and Telomere Length in Community-Dwelling Adults: Findings From the 1999 to 2002 National Health and Nutrition Examination Survey

Chronic pain is a common condition associated with psychological distress, functional impairments, and age-associated comorbidity. Preliminary studies, on the basis of relatively small sample sizes, suggest that the combination of chronic pain and stress is associated with telomere shortening, a widely recognized marker of cellular aging. We sought to determine the cross-sectional association of chronic pain with telomere length in 7,816 community-dwelling adults ages 20 years and older who participated in the 1999 to 2002 National Health and Nutrition Examination Survey. Consistent with previous studies, leukocyte telomere length was assessed using the quantitative polymerase chain reaction method and compared with a DNA reference standard to compute a telomere to single copy gene ratio. Standardized, in-person interviews were used to identify chronic regional pain and chronic widespread pain in 784 (10.0%) and 266 (3.4%) participants, respectively. Older age, male sex, obesity, and less physical activity were associated with shorter telomere length (P?<.05 for all comparisons); however, there was no association of chronic pain with telomere length. The age-adjusted means (standard error) of telomere length telomere to single copy gene ratios were 1.04 (.02), 1.03 (.02), and 1.02 (.02) in participants with no chronic pain, chronic regional pain, and chronic widespread pain, respectively (P?=?.69). In addition, chronic pain did not modify the effects of age, sex, race/ethnicity, education, or psychological distress on telomere length. In summary, chronic regional and widespread pain were not associated with telomere length in this nationally representative study; however, we could not determine associations of pain duration and severity with telomere length because of limitations in pain assessment data.

Audiometric thresholds and prevalence of tinnitus among male veterans in the United States: data from the National Health and Nutrition Examination Survey, 1999-2006

Hearing loss and tinnitus are the two most prevalent service-connected disabilities among U.S. veterans. The number of veterans receiving compensation and services from the Department of Veterans Affairs (VA) for these conditions continues to increase annually. However, the majority of veterans in the United States do not use VA medical centers or clinics for healthcare and do not receive VA compensation payments. Therefore, the prevalence of hearing loss and tinnitus among U.S. veterans is unknown. This study used National Health and Nutrition Examination Survey data to estimate the prevalence of these auditory conditions among male veterans. Between 1999 and 2006, pure tone audiometric data collected from 845 male veterans were compared with pure tone thresholds collected from 2,086 male nonveterans. We used questionnaire data collected between 1999 and 2004 to calculate and compare the prevalence of tinnitus for 2,174 veterans and 4,995 nonveterans. In general, pure tone thresholds did not differ significantly between veterans and nonveterans for most frequencies tested (500-8,000 Hz). The overall prevalence of tinnitus was greater for veterans than that for nonveterans (p < 0.001), with statistically significant differences in the 50 to 59 and 60 to 69 age groups.     

Prevalence of diabetes and impaired fasting glucose in adults in the U.S. population: National Health And Nutrition Examination Survey 1999-2002

OBJECTIVE: The purpose of this study was to examine the prevalences of diagnosed and undiagnosed diabetes, and impaired fasting glucose (IFG) in U.S. adults during 1999-2002, and compare prevalences to those in 1988-1994. RESEARCH DESIGN AND METHODS: The National Health and Nutrition Examination Survey (NHANES) contains a probability sample of adults aged > or =20 years. In the NHANES 1999-2002, 4,761 adults were classified on glycemic status using standard criteria, based on an interview for diagnosed diabetes and fasting plasma glucose measured in a subsample. RESULTS: The crude prevalence of total diabetes in 1999-2002 was 9.3% (19.3 million, 2002 U.S. population), consisting of 6.5% diagnosed and 2.8% undiagnosed. An additional 26.0% had IFG, totaling 35.3% (73.3 million) with either diabetes or IFG. The prevalence of total diabetes rose with age, reaching 21.6% for those aged > or =65 years. The prevalence of diagnosed diabetes was twice as high in non-Hispanic blacks and Mexican Americans compared with non-Hispanic whites (both P < 0.00001), whereas the prevalence of undiagnosed diabetes was similar by race/ethnicity, adjusted for age and sex. The prevalence of diagnosed diabetes was similar by sex, but prevalences of undiagnosed diabetes and IFG were significantly higher in men. The crude prevalence of diagnosed diabetes rose significantly from 5.1% in 1988-1994 to 6.5% in 1999-2002, but the crude prevalences were stable for undiagnosed diabetes (from 2.7 to 2.8%) and IFG (from 24.7 to 26.0%). Results were similar after adjustment for age and sex. CONCLUSIONS: Although the prevalence of diagnosed diabetes has increased significantly over the last decade, the prevalences of undiagnosed diabetes and IFG have remained relatively stable. Minority groups remain disproportionately affected.     

Physical activity, cardiovascular fitness, and insulin sensitivity among U.S. adolescents: the National Health and Nutrition Examination Survey, 1999-2002

OBJECTIVE: The purpose of this study was to examine the association of physical activity and cardiovascular fitness (CVF) with insulin sensitivity in a nationally representative sample of U.S. youth. RESEARCH DESIGN AND METHODS: The study included 1,783 U.S. adolescents (11% Mexican American, 14% non-Hispanic black, 63% non-Hispanic white, and 12% other) aged 12-19 years who were examined in the 1999-2002 National Health and Nutrition Examination Survey. Physical activity was assessed by questionnaire and expressed in units of MET hours per week. Predicted maximal oxygen uptake (Vo(2max), expressed in milliliters per kilogram of body weight per minute), a measure of CVF, was determined by a submaximal multistage treadmill test. Insulin sensitivity was defined by the Quantitative Insulin Sensitivity Check Index. RESULTS: Boys were more likely than girls to be highly active (>or=30 MET h/week; 51 vs. 37%, P < 0.001) and had higher levels of CVF (mean Vo(2max) 47 vs. 39 ml x kg(-1) x min(-1), P < 0.001). Sex-specific multiple regression models controlled for age, race/ethnicity, and BMI showed that in boys, high levels of physical activity and high levels of CVF were significantly and positively associated with insulin sensitivity (beta = 0.84, P < 0.001 and beta = 0.82, P = 0.01, respectively). Among girls, insulin sensitivity was not significantly associated with physical activity or with CVF but was inversely and significantly associated with BMI. CONCLUSIONS: Increasing physical activity and CVF may have an independent effect of improving insulin sensitivity among boys. For girls, the primary role of physical activity may be in weight maintenance.     

Age, sex, and ethnic variations in serum insulin concentrations among U.S. youth: findings from the National Health and Nutrition Examination Survey 1999-2002

OBJECTIVE: Distributions of serum concentrations of insulin among adolescents and young adults are poorly understood in the U.S. The objective of this study was to describe the distribution of serum insulin across demographic characteristics of U.S. adolescents and young adults. RESEARCH DESIGN AND METHODS: A total of 1,791 male and female subjects aged 12-19 years who participated in the National Health and Nutrition Examination Surveys for 1999-2002 were included in the analyses. RESULTS: Among male participants, serum concentrations of insulin increased from age 12 to 14 years before decreasing. Among female participants, concentrations were highest at age 13 years before decreasing steadily through age 19 years. Among participants aged 12-17 years but not those aged 18-19 years, females had higher mean log-transformed concentrations than males (P, Wald, F = 0.038 and 0.125, respectively) after adjusting for age and ethnicity. After adjusting for age and BMI percentile, mean log-transformed concentrations were higher in African-American females aged 12-17 years than in white or Mexican-American participants. No significant ethnic differences were found among female participants aged 18-19 years or male participants aged 12-19 years. Concentrations of insulin increased strongly with increasing levels of BMI. CONCLUSIONS: These results provide detailed information about serum concentrations of insulin in a representative sample of U.S. adolescents and young adults and may be useful to monitor future trends of this risk factor for diabetes and cardiovascular disease.     

Prevalence and risk factors for urinary incontinence in women with type 2 diabetes and impaired fasting glucose: findings from the National Health and Nutrition Examination Survey (NHANES) 2001-2002

OBJECTIVE: Diabetes is associated with increased risk of urinary incontinence. It is unknown whether women with pre-diabetes, or impaired fasting glucose (IFG), have increased prevalence of incontinence. We determined the prevalence of, and risk factors for, incontinence among U.S. women with diabetes and IFG. RESEARCH DESIGN AND METHODS: The 2001-2002 National Health and Nutrition Examination Survey measured fasting plasma glucose and obtained information about diabetes and urinary incontinence among 1,461 nonpregnant adult women. Self-reported weekly or more frequent incontinence, both overall and by type (urge and stress), was our outcome. RESULTS: Of the 1,461 women, 17% had diabetes and 11% met criteria for IFG. Prevalence of weekly incontinence was similar among women in these two groups (35.4 and 33.4%, respectively) and significantly higher than among women with normal fasting glucose (16.8%); both urge and stress incontinence were increased. In addition to well-recognized risk factors including age, weight, and oral estrogen use, two microvascular complications caused by diabetes, specifically macroalbuminuria and peripheral neuropathic pain, were associated with incontinence. CONCLUSIONS: Physicians should be alert for incontinence, an often unrecognized and therefore undertreated disorder, among women with diabetes and IFG, in particular those with microvascular complications. The additional prospect of improvements in their incontinence may help motivate some high-risk women to undertake difficult lifestyle changes to reduce their more serious risk of diabetes and its sequelae.     

C-reactive protein concentration distribution among US children and young adults: findings from the National Health and Nutrition Examination Survey, 1999-2000

BACKGROUND: The distribution of C-reactive protein (CRP) concentrations among children and young adults in the US is not known at present. METHODS: We used data from 3348 US children and young adults 3-19 years of age who participated in the National Health and Nutrition Examination Survey, 1999-2000, to describe the distribution of CRP concentrations, based on results obtained with a high-sensitivity latex-enhanced turbidimetric assay. RESULTS: The range of CRP concentrations was 0.1-90.8 mg/L (mean, 1.6 mg/L; geometric mean, 0.5 mg/L; median, 0.4 mg/L). CRP concentrations increased with age. Females 16-19 years of age had higher concentrations than males in this age range (P = 0.003). Mexican Americans had the highest CRP concentrations among the three major race or ethnic groups (P <0.001). CONCLUSIONS: For the first time, these data describe the CRP concentration distribution among US children and young adults, based on results obtained with a high-sensitivity assay.     

Achievement of American Diabetes Association clinical practice recommendations among U.S. adults with diabetes, 1999-2002: the National Health and Nutrition Examination Survey

OBJECTIVE: To estimate the proportion of U.S. adults with diabetes who meet American Diabetes Association (ADA) clinical practice recommendations. RESEARCH DESIGN AND METHODS: Using data from the 1999-2002 National Health and Nutrition Examination Survey, 998 adults aged >/=18 years with self-reported diabetes were identified. The proportion of adults with diabetes meeting ADA recommendations for HbA(1c) (A1C), HDL cholesterol, LDL cholesterol, triglycerides, blood pressure, renal function, nutrient intake, smoking, pneumococcal vaccination, and physical activity was estimated. RESULTS: Among U.S. adults with diabetes in 1999-2002, 49.8% had A1C <7%; 27.4, 36.0, and 65.0% were classified as low risk for HDL cholesterol, LDL cholesterol, and triglycerides, respectively. Nearly 40% met blood pressure recommendations, 66% had normal renal function, and daily nutrient recommendations for protein, saturated fat, unsaturated fat, and fiber were met by 64.0, 48.3, 28.3, and 18.3%, respectively. Although >81% of the sample reported not smoking at the time of the exam, only 38.2% reported ever having had a pneumococcal immunization, and 28.2% reported getting the recommended level of physical activity. Race, age, duration of diabetes, and education affected achievement of ADA recommendations. CONCLUSIONS: Achievement of ADA clinical practice recommendations is far from adequate in U.S. adults with diabetes.     

A strong dose-response relation between serum concentrations of persistent organic pollutants and diabetes: results from the National Health and Examination Survey 1999-2002

OBJECTIVE: Low-level exposure to some persistent organic pollutants (POPs) has recently become a focus because of their possible link with the risk of diabetes. RESEARCH DESIGN AND METHODS: Cross-sectional associations of the serum concentrations of POPs with diabetes prevalence were investigated in 2,016 adult participants in the National Health and Nutrition Examination Survey 1999-2002. Six POPs (2,2',4,4',5,5'-hexachlorobiphenyl, 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin, 1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxin, oxychlordane, p,p'-dichlorodiphenyltrichloroethane, and trans-nonachlor) were selected, because they were detectable in >or=80% of participants. RESULTS: Compared with subjects with serum concentrations below the limit of detection, after adjustment for age, sex, race and ethnicity, poverty income ratio, BMI, and waist circumference, diabetes prevalence was strongly positively associated with lipid-adjusted serum concentrations of all six POPs. When the participants were classified according to the sum of category numbers of the six POPs, adjusted odds ratios were 1.0, 14.0, 14.7, 38.3, and 37.7 (P for trend < 0.001). The association was consistent in stratified analyses and stronger in younger participants, Mexican Americans, and obese individuals. CONCLUSIONS: There were striking dose-response relations between serum concentrations of six selected POPs and the prevalence of diabetes. The strong graded association could offer a compelling challenge to future epidemiologic and toxicological research.