Is waist-to-height ratio the best predictive indicator of cardiovascular disease incidence in hypertensive adults? A cohort study

Waist-to-height ratio and body fat percentage as risk factors for ischemic cardiovascular disease: a prospective cohort study from UK Biobank

BACKGROUND

The independent effect of waist-to-height ratio (WHtR) and body fat percentage (BF%) on ischemic cardiovascular disease (CVD) remains uncertain.

OBJECTIVES

This study aimed to investigate the independent associations of WHtR and BF% with ischemic CVD.

METHODS

This prospective cohort study used data from the UK Biobank. BF% was calculated as fat mass divided by body weight, measured by bioimpedance. Cox models estimated hazard ratios (HRs) with 95% confidence intervals (CIs) for overall and sex-specific associations of BF% and WHtR with risks of ischemic CVD and its main subtypes [myocardial infarction (MI) and ischemic stroke (IS)], adjusted for a range of potential confounders, including mutual adjustment for BF% and WHtR.

RESULTS

In total, 468,333 participants without existing CVD were included in the analysis. During 12 y of follow-up, 20,151 ischemic CVD events, 13,604 MIs, and 6681 ISs were recorded. WHtR was linearly associated with ischemic CVD, MI, and IS, with an HR per 5% increase of 1.23 (95% CI: 1.20, 1.25), 1.24 (95% CI: 1.21, 1.27), and 1.22 (95% CI: 1.18, 1.26), respectively, independent of BF%. A stronger association between WHtR and MI was seen in females than in males. The association of BF% with these outcomes was substantially attenuated in both sexes after adjustment for WHtR. For example, in females, the HR (highest compared with lowest fifth) was reduced from 1.94 (95% CI: 1.76, 2.15) to 1.04 (95% CI: 0.90, 1.01) for ischemic CVD, from 2.04 (95% CI: 1.79, 2.32) to 0.97 (95% CI: 0.81, 1.16) for MI, and from 1.81 (95% CI: 1.54, 2.13) to 1.07 (95% CI: 0.85, 1.33) for IS.

CONCLUSIONS

WHtR, when used as a proxy measure for central obesity, is linearly associated with ischemic CVD in both sexes, which is independent of BF%. In contrast, the relationship of BF% with these health outcomes is predominantly driven by its correlation with WHtR.

Use of Sex-Specific Body Mass Index to Optimize Low Correlation With Height and High Correlation With Fatness: A UK Biobank Study

Body mass index (BMI; weight (kg)/height (m)2) is commonly used to measure general adiposity. However, evidence of its appropriateness for males and females remains inconsistent. We aimed to identify the most appropriate sex-specific power value that height should be raised to in the formula and the value that would make it achieve height independency and body fatness dependency. We randomly assigned UK Biobank participants recruited in the United Kingdom between 2006 and 2010 (n = 489,873; mean age = 56.5 years; 94.2% White) to training and testing sets (80%:20%). Using height raised to the power of -50.00 to 50.00, we identified the optimal power value that either minimized correlation with height or maximized correlation with body fat percentage, using age-adjusted correlations. The optimal power values for height were 1.77 for males and 1.39 for females. The new formulas resulted in 4.5% of females and 2.4% of males being reclassified into a different BMI category. The formulas did not show significant improvement (in terms of area under the receiver operating characteristic curve, sensitivity, and specificity) in identifying individuals with excessive body fat percentage or in predicting risk of all-cause mortality. Therefore, the conventional BMI formula is still valuable in research and disease screening for both sexes.

Sex-Specific Comparison Between Triglyceride Glucose Index and Modified Triglyceride Glucose Indices to Predict New-Onset Hypertension in Middle-Aged and Older Adults

Background Triglyceride and glucose (TyG) index and TyG-related indices combined with obesity-related markers are considered important markers of insulin resistance. We aimed to examine the association between the TyG index and modified TyG indices with new-onset hypertension and their predictive ability stratified by sex. Methods and Results We analyzed data from 5414 Korean Genome and Epidemiology Study participants aged 40 to 69 years. Multiple Cox proportional hazard regression analyses were conducted to estimate the hazard ratio (HR) and 95% CI for new-onset hypertension according to sex-specific tertile groups after confounder adjustments. To evaluate the predictive performance of these indices for new-onset hypertension, we calculated Harrell's C-index (95% CI). Over a 9.5-year follow-up period, 1014 men and 1012 women developed new-onset hypertension. Compared with the lowest tertile (T) group, the adjusted HR and 95% CI for new-onset hypertension in T3 for TyG, TyG-body mass index, TyG-waist circumference, and TyG-waist-to-height ratio were 1.16 (0.95-1.40), 1.11 (0.84-1.48), 1.77 (1.38-2.27), and 1.68 (1.33-2.13) in men and 1.37 (1.13-1.66), 1.55 (1.16-2.06), 1.43 (1.15-1.79), and 1.64 (1.30-2.07) in women, respectively. The C-indices of TyG-waist-to-height ratio for new-onset hypertension were significantly higher than those of TyG and TyG-body mass index in both men and women. Conclusions TyG and TyG-body mass index were significantly associated with new-onset hypertension only in women. TyG-waist circumference and TyG-waist-to-height ratio were significantly associated with new-onset hypertension in both men and women. A sex-specific approach is required when using TyG and modified TyG indices to identify individuals at risk of incident hypertension.

Association of abdominal obesity and systolic blood pressure indices with cardiovascular disease risk prediction among community-dwelling older adults

<b>Background:</b> Excess adiposity is an established risk factor for cardiovascular disease (CVD), therefore the early screening indies with predicted CVD risk is more useful for older adults. The current study evaluated the associations between anthropometric, body composition and dietary indices and elevated 10-year CVD risk in older people.<br /> <b>Methods:</b> This research, which involved 55 to 94-year-olds living in the community. Standard techniques were used to determine anthropometric factors and body composition indicators. The risk prediction chart created by World Health Organization and International Society of Hypertension was used to calculate the CVD risk score. Odds ratio (OR) and 95% confidence interval (CI) were determined.<br /> <b>Results:</b> CVD risk prediction was positively correlated with the anthropometric and body composition parameters. After controlling for confounding variables, the logistic regression analysis revealed that waist circumference (OR=16.34; 95% CI: 7.22, 36.98; <i>p</i>&lt;0.001), systolic blood pressure (BP) (OR=9.53; 95% CI: 4.52, 20.07; <i>p</i>&lt;0.001), and visceral adipose tissue percentage (OR=5.47; 95% CI: 2.98, 10.01; <i>p</i>&lt;0.001) were correlated with cardiovascular risk prediction.<br /> <b>Conclusions:</b> Abdominal obesity and increase of systolic BP were associated to increased risk for CVD. Additionally, a positive association between the risk factors for CVD (%visceral adipose tissue) and diet (cholesterol consumption) was established.

Serum Folate Related to Five Measurements of Obesity and High-Sensitivity C-Reactive Protein in Korean Adults

This study investigated the effects of folic acid on obesity and high-sensitivity C-reactive protein (CRP) levels. Using data from the Korea National Health and Nutrition Examination Survey (KNHANES VII 2016–2018), 6394 adults (aged 19–80 years) who met the study criteria were identified and divided into young, middle-aged, and older adult groups. The analysis assessed associations using logistic regression for complex samples. Obesity was measured using body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), a body shape index (ABSI), and body roundness index (BRI). The odds ratio (OR) of obesity based on BMI were statistically significant for young adults and older participants with low levels of folic acid compared to those with high levels (OR: 1.33 and 1.58, respectively). The OR of obesity based on BMI, WC, WHtR, ABSI, and BRI was significant with low levels of folic acid in middle-aged individuals (OR: 1.36, 1.32, 1.41, 1.29, and 1.47, respectively). Low folate levels were related to higher high-sensitivity CRP levels in middle-aged patients. In conclusion, folate level showed a significant inverse association with obesity and inflammatory biomarkers, especially in the middle-aged group. Further longitudinal or randomized controlled trials are needed to confirm and expand our results.