Relative leg length is associated with type 2 diabetes differently according to pubertal timing: The Brazilian longitudinal study of adult health

Abstract

Objectives Studies from developed societies have shown that individuals with short legs relative to height have higher risk of type 2 diabetes. This has been much less explored in less developed populations where influences on relative leg length and diabetes may differ. The Brazilian Longitudinal Study of Adult Health (in Portuguese, ELSA-Brasil) allows us to test, in a cohort born (1934–1975) and raised when undernutrition was common, whether short legs relative to height is positively associated with diabetes, independent of early-life factors, including birth weight, age at menarche, and young-adult BMI. Methods We used baseline, cross-sectional data from 15,105 participants aged 35–74 years participating in ELSA-Brasil. We created age-and-sex-specific Z scores for leg length index (leg length/height x 100) according to an external reference. Diabetes was defined by self-reported physician diagnosis, medication use, fasting and 2-hour post-75g-load glucose, and A1C. Results A one-unit decrement in leg-length-index Z score was associated with 12% (8–17%) higher prevalence of diabetes in Brazilian adults, after adjustment through Poisson regression for confounders, including race, maternal education, and birth weight. This association persisted after further adjustment for menarche age, BMI (at age 20), buttocks circumference, and waist circumference. It was stronger among women with early menarche (p interaction=0.02). Leg length index was also positively associated with fasting glucose, fasting insulin, 2-hour glucose, and A1C (p<0.05). Conclusions In contemporary Brazilian adults, short legs relative to height is positively associated with diabetes independent of measures of intrauterine growth, pubertal timing, young-adult adiposity. This association is stronger in women with early menarche.

Leg length and type 2 diabetes

“…[8] After adjustment for potential early-life confounders and BMI at age 20 years, a one-unit decrement in relative leg-length Z score was associated with 12% higher prevalence of diabetes in men and women. This association was stronger in women who had earlier menarche onset.…”

“…[8] There are several biologic mechanisms that may explain this interaction. Earlier age at menarche, which itself is associated with greater type 2 diabetes risk,[12] may represent greater early-life adiposity.…”

Early-life factors are associated with waist circumference and type 2 diabetes among Ghanaian adults: The RODAM Study

“…Among white populations living in high-income countries, shorter legs and lower LHR are consistently associated with higher measures of adiposity and diabetes-risk, including the PROMISE cohort in Canada as well as NHANES III and ARIC in the USA 11,20,30,31 . Still, the evidence has been scarce and inconclusive for individuals of African descent and for populations in less-developed regions, such as China and Brazil 10,11,30,32,33 .…”

Early-life exposures and cardiovascular disease risk among Ghanaian migrant and home populations: the RODAM study

“…27 Observations from other populations also showed an association between leg length and age at menarche. 28,58,59 A study based on the third National Health And Nutrition Survey found that earlier menarche was associated with shorter stature, mainly due to shorter leg length. 28 The association between age at menarche and leg length, however, depends on the contextual environment; earlier menarche predicts taller stature among developing countries, whereas it predicts shorter stature in developed countries.…”