Anthropometric measurements of obesity in relation to mortality and cancer incidence among European adults
Year: 2015
Type: dissertation
Abstract: Background and aims: Obesity has become the sixth most important risk factor contributing to the overall burden of a variety of diseases worldwide. The association of anthropometric measures of obesity with mortality from various causes and incidence of cancers of various sites has been investigated, but it remains controversial. The aims of this study were to: 1) evaluate the epidemiological nature of the association of anthropometric measures of obesity with mortality from various causes, and to detect a potential threshold in this association; 2) study the epidemiological nature of the association between body mass index and incidence of cancer of different sites, and to detect a potential threshold in the association; 3) compare the strengths of different anthropometric measures of obesity in relation to cardiovascular disease (CVD) mortality; 4) assess the risk of CVD mortality in relation to obesity and sex in the general population, and also separately for those with or without diabetes at baseline. Study population and Methods: This study was based on data subsets of the Diabetes Epidemiology: Collaborative analysis Of Diagnostic criteria in Europe (DECODE) study and the National FINRISK study, including 72 947 European men and 62 798 women (I), 26 636 Finnish men and 28 089 women (II), 24 686 European men and 21 965 women (III/IV), and 23 629 European men and 21 965 women (V) aged 24 years or above at baseline. Hazard ratios (HRs) corresponding to categorical or continuous body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) or waist-to-stature ratio (WSR), a body shape index (ABSI) and waist-to-hip-to-height ratio (WHHR) were estimated by the Cox proportional hazards model adjusting for several potential confounding factors measured at baseline. The non-parametric smooth functions of several anthropometric measures of obesity were fitted to health outcomes in order to explore the potential curvilinear relationship using the spline regression model, with a threshold detected by a piecewise regression model (II/III). HR per standard deviation increment of each anthropometric measure of obesity in relation to CVD mortality was compared using the paired homogeneity test (IV). Results: BMI, WC and WHtR had a U- or J-shaped relationship with all-cause mortality (I/III), whereas WHR, ABSI and WHHR had a linear positive relationship with all-cause mortality (III). BMI had a J-shaped relationship with CVD mortality (I/III), whereas anthropometric measures of abdominal obesity (WC, WHR, WHtR and ABSI) had a linear positive relationship with CVD mortality (III). BMI had a U-shaped relationship with cancer mortality in both men and women but disappeared among non-smokers, which showed no association (I). BMI had a linear positive association with incidence of cancers of the colon, liver, kidney, bladder and all sites combined in men, and of cancers of the stomach, colon, gallbladder and ovary in women, an inverse association with incidence of cancers of the lung in men and the lung and breast in women, and a J-shaped association with incidence of all cancers combined in women (II). A one-standard-deviation increase in all obesity indicators were significantly associated with a more than 19% increase of CVD mortality risk in both men and women, and the prediction for CVD mortality was stronger with anthropometric measures of abdominal obesity than that with BMI and ABSI, and most strongly with the WHtR/WSR (IV). Men had higher CVD mortality rates and higher HRs across BMI categories, and categories of abdominal obesity than women (V). The sex difference in CVD mortality was slightly smaller in obese than in non-obese individuals; the negative interactions were statistically significant between sex and WC (p =0.02), and sex and WHtR (p =0.01). None of the interaction terms was significant when the analyses were carried out among non-diabetic or diabetic individuals separately (V). Conclusions: This study confirmed the deleterious effect of obesity on mortality from various causes and incidence of cancers of certain sites. The prediction for CVD mortality with anthropometric measures of abdominal obesity was stronger than that with BMI, which may imply a more important role of fat distribution than fat accumulation and suggest that an effective obesity prevention strategy should emphasize the importance of abdominal obesity. Men had higher CVD mortality than women across all categories of anthropometric measures of obesity, which further supports the view of higher intra-abdominal fat accumulation in men than in women, even in non-obese individuals. Obesity seems slightly to diminish the female advantage in CVD mortality, irrespective of diabetes status. This may indicate that women may gradually lose their cardiovascular advantage when they are obese, probably due to a more pronounced clustering of CVD risk factors among obese women.
Source: Työväentutkimus Vuosikirja
Author: Xin Song
Language: English
Topic: Cancer Risks and Factors
Subfield: Oncology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W1468825018