The population distribution of the sagittal abdominal diameter (SAD) and SAD/height ratio among Finnish adults.

Sagittal abdominal diameter (SAD; 'abdominal height' measured in supine position) may improve upon conventional anthropometry for predicting incident cardiometabolic diseases. However, the SAD is used infrequently by practitioners and epidemiologists. A representative survey of Finnish adults in 2000-2001 collected body measurements including SAD (by sliding-beam calliper) using standardized protocols. Sampled non-pregnant adults (ages 30+ years; 79% participation) provided 6123 SAD measurements from 80 health centre districts. Through stratified, complex survey design, these data represented 2.86 million adults at ages 30+ years. SAD ranged from 13.5 to 38.0 cm, with a population mean (standard error) of 21.7 (0.05) cm and median (interquartile range) of 21.0 (19.1-23.4). Median SAD was higher at ages 50+ years compared with ages 30-49 both for men (22.4 [20.5-24.6] vs. 20.8 [19.3-22.7]) and women (21.7 [19.6-23.9] vs. 19.4 [17.8-21.4]). The SAD/height ratio was similar (0.118) for both sexes at 30-39 years, rising more steeply with age for women than men. Attaining only a basic education, compared with a high level, was associated with increased mean (95% confidence interval) SADs for men (22.6 [22.3-22.8] vs. 22.0 [21.7-22.2]) and women (21.8 [21.5-22.0] vs. 20.6 [20.4-20.8]). Finland's early experience with nationally representative SAD measurements provides normative reference values and physiological insights useful for investigations of cardiometabolic risk.

Comparison of two waist circumference measurement protocols: the SEARCH for diabetes in youth study.

BACKGROUND: Reports comparing waist circumference (WC) measurements from young populations are scarce. OBJECTIVES: We compared two protocols for measuring waist circumference in a sample of youth with diabetes. METHODS: Participants were enrolled in the SEARCH for Diabetes in Youth Study (SEARCH). WC was measured at least twice by the National Health and Nutrition Examination Survey (NHANES) protocol and twice by the World Health Organization (WHO) protocol. Method-specific averages were used in these analyses. RESULTS: Among 6248 participants, the mean NHANES WC (76.3 cm) was greater than the mean WHO WC (71.9 cm). Discrepancies between protocols were greater for females than males, among older participants, and in those with higher body mass index (BMI). In both sexes and four age strata, the WCs using either method were highly correlated with BMI z-score. The within-method differences between the first and second measurements were similar for the two methods. CONCLUSIONS: These analyses do not provide evidence that one of these two methods is more reproducible or is a better indicator of obesity as defined by BMI z-scores.

Recent population changes in HbA(1c) and fasting insulin concentrations among US adults with preserved glucose homeostasis.

AIMS/HYPOTHESIS: Although diagnosed type 2 diabetes has increased in the past decade, little is known about accompanying changes in fasting plasma glucose (FPG), HbA(1c) and fasting serum insulin (FI) levels in the non-diabetic population. METHODS: Using population estimates from National Health and Nutrition Examination Surveys, we compared distribution of FPG, HbA(1c) and FI in non-diabetic US persons who were >or=20 years old in 1999 to 2006 with that in persons of the same age in 1988 to 1994. RESULTS: Age-, sex- and race-adjusted mean FPG levels between the two study periods did not change, but mean HbA(1c) and FI levels increased (0.10% and 4.8 pmol/l, respectively; p < 0.001 for both). The increased HbA(1c) level was driven largely by an upward shift in the lower end of the HbA(1c) distribution. In contrast, the increased FI level was driven primarily by an upward shift in the middle and higher end of FI distribution, especially among persons aged 20 to 44 years. After adjustments for BMI or waist circumference, the increase in the mean HbA(1c) level was attenuated (0.06%; p < 0.001), whereas the mean FPG level decreased by 0.1 mmol/l (p < 0.001) and the mean FI level no longer demonstrated significant change. CONCLUSIONS/INTERPRETATION: Despite little change in the distribution of FPG levels, HbA(1c) and FI levels increased in the non-diabetic population in the past decade. The increase in FI levels suggests that levels of insulin resistance were greater among US adults, especially young adults, than in the previous decade.

Prenatal environmental exposures that may influence ß-cell function or insulin sensitivity in middle age.

The associations between fetal environment and diabetes risk are likely mediated by the offspring's diminished pancreatic ß-cell function or reduced insulin sensitivity. Our ability to distinguish between these mechanisms is impeded by the lack of markers describing an individual's gestational environment. Fingerprints, however, are permanently fixed in the first half of gestation, and increased values of a dermatoglyphic marker that contrasts fingerprint ridge counts between the thumbs and fifth fingers (Md15) have been linked to type 2 diabetes. Among 763 adults without known diabetes from the Dutch Hunger Winter Families Study, we tested the associations of Md15 with homeostatic assessment indices of ß-cell function (HOMA-b) and insulin sensitivity (QUICKI). For either outcome index, linear regression models included terms for Md15 tertiles and for maternal history of diabetes as reported by each participant. All models were corrected for sibling pairs and adjusted for age, sex and famine exposures. Increased Md15 was associated with decreased HOMA-b (P = 0.03 for Md15 tertile 3 v. 1) but not with QUICKI. In contrast, maternal history of diabetes was associated with decreased QUICKI (P < 0.001) but not with HOMA-b. Birth weight (available for 520 participants) was positively associated with increased QUICKI (P = 0.04 for birth weight tertile 3 v. 1) but not with HOMA-b. Fingerprint Md15, maternal history of diabetes and birth weight may help to identify specific defects in the control of adult glucose metabolism. Research into the environment associated with Md15 variation may suggest prenatal strategies for optimizing ß-cell function in adult life.

Longitudinal changes in BMI and in an index estimating excess lipids among white and black adults in the United States.

BACKGROUND: Adult obesity prevalence is influenced by rates of weight gain or loss among individual persons, but few studies have measured individual weight change in large populations. Changes in weight may not coincide with changes in the lipid accumulation product (LAP), a continuous index derived from waist circumference and triglycerides concentration for estimating excess lipids. DESIGN AND MEASUREMENTS: Descriptive report of longitudinal changes from US studies that included body mass index (BMI, kg/m(2)) and LAP. SUBJECTS: A total of 16 763 white and black adults studied between 1989 and 1996 in three observational cohorts (Coronary Artery Risk Development in Young Adults, Atherosclerosis Risk in Communities Study and Cardiovascular Health Study). RESULTS: The means of individual annual changes in BMI were positive for young adults, but the mean changes were reduced at older ages (P for linear trend <0.001), becoming negative after 73-83 years old. These mean, individual changes in BMI, specific to sex and age, were approximately 0.1 U/year greater than those reported from previous, representative, longitudinal measurements collected in the United States between 1971 and 1984. Mean, individual annual changes in LAP were strongly positive before middle age. For men, the annual LAP changes were reduced at older ages (P linear trend <0.05). For women, they were greater at older ages (white women, P<0.001) or remained unchanged (black women, P>0.3). With increasing age, there was a greater proportion of persons whose positive LAP change was accompanied by simultaneous BMI change that was negative or zero. CONCLUSIONS: These longitudinal observations made during 1989-1996 suggest greater annual changes in BMI compared to an adult cohort studied during 1971-1984. As estimated by LAP, adults of all ages tended to accumulate excess lipids, including circumstances in which they lost weight.

Does the relationship between waist circumference, morbidity and mortality depend on measurement protocol for waist circumference?

There is currently no consensus regarding the optimal protocol for measurement of waist circumference (WC), and no scientific rationale is provided for any of the WC protocols recommended by leading health authorities. A panel of experts conducted a systematic review of 120 studies (236 samples) to determine whether measurement protocol influenced the relationship of WC with morbidity of cardiovascular disease (CVD) and diabetes and with mortality from all causes and from CVD. Statistically significant associations with WC were reported for 65% (152) of the samples across all outcomes combined. Common WC protocols performed measurement at the minimal waist (33%), midpoint (26%) and umbilicus (27%). Non-significant associations were reported for 27% (64) of the samples. Most of these protocols measured WC at the midpoint (36%), umbilicus (28%) or minimal waist (25%). Significant associations were observed for 17 of the remaining 20 samples, but these were not significant when adjustment was made for covariates. For these samples, the most common WC protocols were the midpoint (35%) and umbilicus (30%). Similar patterns of association between the outcomes and all WC protocols were observed across sample size, sex, age, race and ethnicity. Our findings suggest that WC measurement protocol has no substantial influence on the association between WC, all-cause and CVD mortality, CVD and diabetes.

Hyperinsulinemia predicts fatal liver cancer but is inversely associated with fatal cancer at some other sites: the Paris Prospective Study.

OBJECTIVE: To investigate whether insulin is a risk factor for death by site-specific cancers. RESEARCH DESIGN AND METHODS: This was a prospective cohort study of 6,237 nondiabetic French working men between ages 44 and 55 years at baseline from the Paris Prospective Study cohort. Death by site-specific cancers was investigated in relation to baseline insulin concentrations during fasting and 2 h after a 75-g oral glucose tolerance test. RESULTS: Of the original 6,237 men in the cohort, 1.739 died over the 23.8 years of follow-up. 778 (45%) from cancer. Baseline hyperinsulinemia, both fasting and 2-h, was significantly associated with fatal liver cancer, with age-adjusted standardized hazards ratios of 2.72 (95% CI 1.87-3.94) and 3.41 (2.23-5.21). In contrast, fasting hyperinsulinemia was inversely associated with fatal lip, oral cavity, and pharynx cancer and larynx cancer, with hazards ratios of 0.55 (0.41-0.75) and 0.63 (0.47-0.83), respectively; 2-h insulin concentrations were inversely associated with stomach and larynx cancers (hazards ratios 0.62 [0.43-0.90] and 0.66 [0.50-0.891, rcspectively). These relationships were stable after adjusting for other risk factors. Insulin concentrations remained negatively associated with deaths from these cancers in analyses restricted to men who smoked and in those who were not chronic alcohol consumers.

Fingerprint ridge-count difference between adjacent fingertips (dR45) predicts upper-body tissue distribution: evidence for early gestational programming.

Fingerprint ridge counts, which remain constant from the 19th week of pregnancy, are related to fingertip growth during early gestation. Each finger corresponds neurologically to a spinal-cord segment ranging from C6 (thumb, relatively cephalad) to C8 (fifth finger, relatively caudad). The authors hypothesized that large ridge-count differences between fingertips (cephalad > caudad) might reflect fetal inhibition of caudal growth. Among 69 male Atlanta, Georgia, military recruits (1994-1997; aged 17-22 years), they tested associations of the anthropometric waist-to-thigh ratio with 20 ridge-count differences. Waist-to-thigh ratio was associated with the ridge-count difference between the right fourth and fifth fingertips only (dR45; r = 0.36, p = 0.003). The race-adjusted standardized regression coefficient was 0.22 (95% confidence interval: 0.03, 0.41). Since upper-body tissue distribution indicates disease risk, the authors then tested the association of age (an indicator of survivorship) with dR45 in a sample of 135 male patients from Bangalore, India (1989-1990; aged 38-82 years). Age was inversely associated with dR45 (r = -0.17, p = 0.04), notably among the 75 men with diabetes (r = -0.22, p = 0.06). An increased dR45 predicts an upper-body tissue distribution originating before the midpoint of pregnancy. The cause of this developmental pattern is unknown, but it may lead to reduced survivorship.

Body mass index and colon cancer mortality in a large prospective study.

Obesity has been reported to increase the risk of colon cancer, especially in men. The authors examined this relation in the American Cancer Society's Cancer Prevention Study II, a nationwide mortality study of US adults. After 12 years of follow-up, 1,616 deaths from colon cancer in women and 1,792 in men were observed among 496,239 women and 379,167 men who were cancer free at enrollment in 1982. The authors used Cox proportional hazards analyses to control for effects of age, race, education, smoking, exercise, alcohol, parental history of colon cancer, fat intake, vegetable and grain intake, aspirin use and, in women, estrogen replacement therapy. In men, death rates from colon cancer increased across the entire range of body mass index (BMI). The rate ratio was highest for men with BMI > or =32.5 (rate ratio (RR) = 1.90, 95% confidence interval (CI): 1.46, 2.47) compared with men with BMI between 22.00 and 23.49. In women, a weaker association was seen in the three BMI categories of 27.5-29.9 (RR = 1.26, 95% CI: 1.03, 1.53), 30.0-32.4 (RR = 1.37, 95% CI: 1.09, 1.72), and > or =32.5 (RR = 1.23, 95% CI: 0.96, 1.59). These prospective data support the hypothesis that obesity increases the risk of colon cancer death and that the relation is stronger and more linear in men than in women.

Relation of birth weight to lean and fat thigh tissue in young men.

BACKGROUND: Birth weight is positively associated with body mass index (BMI, kg/m2) in later life, but is inversely associated with cardiovascular risk. To understand this paradox, we examined the relationships between birth weight, adult BMI, and estimations of lean and fat tissue in young men. METHODS: From 192 applicants for military service (ages 17-22 y, mean BMI 23.2 kg/m2) with known birth weights we measured the circumference and anterior skinfold thickness at midthigh to estimate thigh muscle+bone area and subcutaneous fat area. Linear regression models including birth weight as the independent variable were adjusted for race and adult height. RESULTS: BMI was linearly associated with birth weight (standardized regression coefficient, [SRC]=+0.27; P=0.0004), as was the thigh muscle+bone area (SRC=+0.22; P=0.0029), but not the thigh subcutaneous fat area (SRC=+0.13; P=0.086). The BMI-birth weight association was reduced by 68% when the regression model was further adjusted for thigh muscle+bone area. Separate adjustment for thigh subcutaneous fat, however, reduced the BMI-birth weight association by only 30%. Waist circumference was also associated with birth weight (SRC=+0.24; P=0.0014), sagittal abdominal diameter was weakly associated (SRC=+0.17; P=0.028), but waist/thigh ratio and abdominal diameter index were not associated with birth weight. INTERPRETATION: The larger BMI associated with higher birth weight may reflect increments in lean tissue more than increments in fat. Birth weight's influence on lean tissue is observed in the thigh and, among fit young men, perhaps at the waist. Increased muscularity in young men may partly explain the cardiovascular benefit in middle age ascribed to higher birth weight.

Increased cancer mortality following a history of nonmelanoma skin cancer.

CONTEXT: Cancer registries have reported an increased incidence of melanoma and certain noncutaneous cancers following nonmelanoma skin cancer (NMSC). Whether these findings were attributable to intensified surveillance, shared risk factors, or increased cancer susceptibility remains unclear. OBJECTIVE: To determine whether a history of NMSC predicts cancer mortality. DESIGN: Prospective cohort with 12-year mortality follow-up adjusted for multiple risk factors. SETTING: Cancer Prevention Study II, United States and Puerto Rico. PARTICIPANTS: Nearly 1.1 million adult volunteers who completed a baseline questionnaire in 1982. MAIN OUTCOME MEASURE: Deaths due to all cancers and common cancers. RESULTS: After adjusting for age, race, education, smoking, obesity, alcohol use, and other conventional risk factors, a baseline history of NMSC was associated with increased total cancer mortality (men's relative risk [RR], 1.30; 95% confidence interval [CI], 1.23-1.36; women's RR, 1.26; 95% CI, 1.17-1.35). Exclusion of deaths due to melanoma reduced these RRs only slightly. Mortality was increased for the following cancers: melanoma (RR, 3.36 in men, 3.52 in women); pharynx (RR, 2.77 in men, 2.81 in women); lung (RR, 1.37 in men, 1.46 in women); non-Hodgkin lymphoma (RR, 1.32 in men, 1.50 in women); in men only, salivary glands (RR, 2.96), prostate (RR, 1.28), testis (RR, 12.7), urinary bladder (RR, 1.41), and leukemia (RR, 1.37); and in women only, breast (RR, 1.34). All-cause mortality was slightly increased (adjusted men's RR, 1.03 [95% CI, 1.00-1.06]; women's RR, 1.04 [95% CI, 1.00-1.09]). CONCLUSIONS: Persons with a history of NMSC are at increased risk of cancer mortality. Although the biological mechanisms are unknown, a history of NMSC should increase the clinician's alertness for certain noncutaneous cancers as well as melanoma.

Sagittal abdominal diameter as a practical predictor of visceral fat.

OBJECTIVE: To evaluate the relationships between the supine sagittal abdominal diameter (SAD) and visceral fat, as well as to evaluate intra- and inter-observer reliability of sagittal diameter measurement. PATIENTS: Twenty-eight women ranging in age from 27-78 y with a body mass index (BMI) ranging from 16.9-48.1 kg/m2 and 23 men ranging in age from 32-75 y with BMI ranging from 20-41.6 kg/m2. MEASUREMENT: Body fat distribution was measured by waist circumference, waist to hip ratio (WHR), SAD, anthropometrically assessed and a single slice of computed tomography (CT) at the L4-L5 level. RESULTS: In both genders, a significant association was found between visceral adipose tissue (AT) and SAD, as evaluated by CT (women r = 0.80; men r = 0.83, P < 0.001), and SAD by anthropometry (women r = 0.76; men r = 0.82, P < 0.001), as well as between visceral AT and waist circumference (women r = 0.76, men r = 0.86, P < 0.001) and WHR (women r = 0.57, P < 0.01, men r = 0.80, P < 0.001). A significant association was also found between subcutaneous AT and SAD by anthropometry (women r = 0.79, men r = 0.74, P < 0.001). After adjusting for BMI, the association between subcutaneous AT and SAD was no longer significant in men and only moderately significant in women (r = 0.42, P < 0.05), while the association between visceral AT and SAD by anthropometry remained significant in both genders (women r = 0.63, P < 0.001; men r = 0.66, P < 0.001). When the subjects were divided into two groups according to BMI (lean to moderately overweight women with BMI < 28 and men with BMI < 30 and obese women with BMI > 28 and men with BMI > 30) we found that the relationships between SAD by anthropometry, as well as SAD by CT and visceral AT, were higher in lean to moderately overweight subjects than in those who were obese. High inter-observer correlation was found concerning SAD measurement (r = 0.99, P < 0.001). Intra- and inter-observer precision as evaluated by coefficient of variation and intraclass correlation coefficient for SAD measurement was very high. CONCLUSION: Our study shows the usefulness of SAD by anthropometry to predict visceral fat and its very high inter- and intra-observer precision.

Are geographic regions with high income inequality associated with risk of abdominal weight gain?

Geographic regions characterized by income inequality are associated with adverse mortality statistics, but the pathophysiologic mechanisms that mediate this ecologic relationship have not been elucidated. This study used a United States mail survey of 34158 male and 42741 female healthy-adult volunteers to test the association between residence in geographic regions with relative income inequality and the likelihood of weight gain at the waist. Respondents came from 21 states that were characterized by the household income inequality (HII) index, a measure reflecting the proportion of total income received by the more well off 50% of households in the state. The main outcome measure was self-reported weight gain mainly at the waist as opposed to weight gain at other anatomic sites. After controlling for age, other individual-level factors, and each state's median household income, men's likelihood of weight gain at the waist was positively associated (p = 0.0008) with the HII index. Men from states with a high HII (households above the median receive 81.6% to 82.6% of the income) described weight gain at the waist more often than men from states with a low HII (households above the median receive 77.0% to 78.5% of the income) (odds ratio = 1.12, 95% confidence interval 1.03 to 1.22). Women's results showed a non-significant trend in the same direction. An association between ecologically defined socio-environmental stress and abdominal obesity may help to clarify the pathophysiologic pathways leading to several major chronic diseases.