A clinical perspective of obesity, metabolic syndrome and cardiovascular disease

The metabolic syndrome is a condition characterized by a special constellation of reversible major risk factors for cardiovascular disease and type 2 diabetes. The main, diagnostic, components are reduced HDL-cholesterol, raised triglycerides, blood pressure and fasting plasma glucose, all of which are related to weight gain, specifically intra-abdominal/ectopic fat accumulation and a large waist circumference. Using internationally adopted arbitrary cut-off values for waist circumference, having metabolic syndrome doubles the risk of cardiovascular disease, but offers an effective treatment approach through weight management. Metabolic syndrome now affects 30–40% of people by age 65, driven mainly by adult weight gain, and by a genetic or epigenetic predisposition to intra-abdominal/ectopic fat accumulation related to poor intra-uterine growth. Metabolic syndrome is also promoted by a lack of subcutaneous adipose tissue, low skeletal muscle mass and anti-retroviral drugs. Reducing weight by 5–10%, by diet and exercise, with or without, anti-obesity drugs, substantially lowers all metabolic syndrome components, and risk of type 2 diabetes and cardiovascular disease. Other cardiovascular disease risk factors such as smoking should be corrected as a priority. Anti-diabetic agents which improve insulin resistance and reduce blood pressure, lipids and weight should be preferred for diabetic patients with metabolic syndrome. Bariatric surgery offers an alternative treatment for those with BMI ≥ 40 or 35–40 kg/m2 with other significant co-morbidity. The prevalence of the metabolic syndrome and cardiovascular disease is expected to rise along with the global obesity epidemic: greater emphasis should be given to effective early weight-management to reduce risk in pre-symptomatic individuals with large waists

Life expectancy of white and non-white elite heavyweight boxers

Background: In post-industrial countries, ethnic minorities suffer poorer health and premature deaths. The present study examined ethnic differences in life expectancy and related features among elite heavyweight boxers. Methods: Dates of birth and death, anthropometry, and championship years were gathered from media archives for champions and challengers (never been a champion) between years 1889 and 2019. Cox regression adjusted for age at contest, nationality, BMI, champion/challenger status, and number of contests was used to assess survival. Results: All 237 boxers, 83 champions (37.3% whites) and 154 challengers (61.0% whites), who contested for heavyweight championships were identified. By 2019, 110 (75 whites, 34 non-whites) were known to have died. Non-white boxers died at an earlier age than whites boxers (mean ± SD = 59.8 ± 14.2 years versus 67.3 ± 16.4 years, p = 0.018) and had shorter survival: HR = 2.13 (95% CI = 1.4–3.3). Among non-white boxers, deaths were higher from neurological disorders: OR = 8.2 (95% CI = 1.3–13.5) and accidents: OR = 15.1 (95% CI = 2.3–98.2), while death from natural causes was lower: OR = 0.2 (95% CI = 0.03–0.8). After boxing careers, fewer non-white boxers had non-manual jobs (34.4% versus 71.8%) than manual (34.4% versus 19.7%) or were unemployed (28.1% versus 2.8%). Reported substance abuse was similar across ethnicity (8.0% versus 8.8%) but conviction rates were higher among non-white boxers (17.6%) than white (1.3%). Conclusions: Compared with white boxers, non-white boxers tend to die younger with excess neurological and accidental deaths, and they have lower social positions in later life. Sporting authorities should reappraise the wisdom of permitting head injuries in sport and monitor and support the health and wellbeing of sports men and women after retirement

Attenuation of the association between sugar-sweetened beverages and diabetes risk by adiposity adjustment: a secondary analysis of national health survey data

Purpose: While weight gain and obesity are the dominant factors, dietary sugar and specifically sugar-sweetened beverages (SSB) has been implicated in causing type 2 diabetes (T2DM). We assessed how much of the apparent effect of SSB is explained by adiposity, but not captured by adjustment for BMI, which is a poor index of body fat. Methods: We examined data from 5187 adults (mean age 50.8 years, SD = 16.4, 172 (3.3%) T2DM), from the Scottish Health Survey 2003 and 2008–2010 databases. Logistic regression was used to assess the association between SSB consumption and T2DM (non-insulin treated) and its attenuation (reduction in odds ratios, ORs), after entering published anthropometric indices of adiposity into the regression model, adjusted for age, sex, social class, education, smoking, alcohol consumption and physical activity. Results: Compared with low SSB categories (“less often/never”, once/week or 1–3 times/month), the OR without adiposity adjustment for having T2DM in high SSB consumers (2–3, 4–5, ≥ 6/day) was 2.56 (95% CI 1.12–5.83; p = 0.026). That OR was marginally changed by adjusting for BMI (+ 4.3%), WC (+ 5.5%) or total body fat (− 4.3%), but greatly attenuated by adjusting for estimated %body fat (− 23.4%). These indices had similar influences on the associations between SSB and T2DM combining known T2DM patients with unknown HbA1c > 6.5%, > 48 mmol/mol. Conclusions: Associations between SSB and T2DM are attenuated more markedly by adjustment with estimated %body fat than with BMI, indicating an adiposity effect not captured using BMI. Future research should employ best available estimates of adiposity

Secular trends in adiposity and musculoskeletal dimensions of elite heavyweight boxers between 1889 and 2019

Purpose: With improving nutrition and health, athletes have grown taller and heavier over the past century. Since there is no weight restriction in the heavyweight class, secular changes in anthropometric measurements of heavyweight boxers may mirror those of contemporary general populations. Objectives: We aimed to (1) examine secular trends in adiposity and musculoskeletal measurements in heavyweight boxers, (2) determine anthropometric differences between champions and unsuccessful challengers. Methods: Detailed demographics taken at time of contest (first official World Championship to current contest: 1889–2019) were collected from media archives. Results: All 237 boxers (83 champions, 154 challengers) contesting a recognised heavyweight World Championships were identified. They had mean (± SD) age = 28.9 ± 4.1 years, height = 187.3 ± 6.5 cm, reach = 195.2 ± 9.4 cm, weight = 97.5 ± 11.5 kg, BMI = 27.8 ± 2.4 kg/m2 and waist = 87.9 ± 6.2 cm. Contest years explained 25.9% (p < 0.001) of the variance in BMI for champions and 30.9% (p < 0.001) for challengers, 9.1% (p < 0.071) in WC for champions and 19.9% (p < 0.001) for challengers. Contest years correlated with height (r = 0.531, p < 0.001), reach (r = 0.341, p < 0.001), weight (r = 0.603, p < 0.001) and BMI (r = 0.370, p = 0.001) among all documented boxers, and with waist only in challengers (r = 0.349, p < 0.001) but not in champions (r = 0.078, p = 0.509). Compared with challengers, champions had greater stature by + 3.4 cm (p < 0.001), reach + 3.6 cm (p = 0.005) and weight + 3.7 kg (p = 0.017), with similar BMI and waist. Champions had larger biceps and forearms but did not differ from challengers in other musculoskeletal dimensions. Conclusions: Over 130 years elite heavyweight boxers have increased in size (BMI) and reach but waists in champions have remained static. Being heavier, taller with longer and bigger arms, but with similar in BMI and waist, appear to be differentiating factors between champions and challengers