Birth weight of 2.5 kg or more linked to risk of developing type 2 diabetes in adulthood, says report
It is associated with lower levels of key glucose regulator hormone
Type 2 diabetes is a serious public health threat associated with high disease and death rates. Evidence indicates that susceptibility to type 2 diabetes over the life course is determined jointly by risk factors in both early life and adulthood. In a new analysis, researchers throw more light on the issue and suggest that birth weight of 2.5 kg or more is “strongly linked” to the risk of developing type 2 diabetes in adulthood.
According to the analysis, a weight of 2.5 kg or more at birth is associated with lower circulating levels of insulin-like growth factor-1, or IGF-1 for short, a hormone similar to insulin that affects childhood growth and energy metabolism in adults. “Our results indicate that birth weight significantly modifies the relation between adulthood levels of circulating IGF-1 and the risk of type 2 diabetes. Evidence has shown that the ethnicity may affect the circulating IGF-1 levels; hence, studies in other ethnic populations are needed,” say authors in the paper published in the online journal BMJ Open Diabetes Research & Care.
American Diabetes Month: What are the complications? They can be disabling or life-threatening over time
Currently, the seventh leading cause of death in the US, more than 34 million Americans — about 1 in 10 — have diabetes. However, 1 in 5 of them do not know that they have the disease. While type 2 diabetes accounted for approximately 90% to 95% of all diagnosed cases of diabetes in 2018, type 1 diabetes accounted for approximately 5 to 10%, according to the 2020 National Diabetes Statistics Report, a periodic publication of the Centers for Disease Control and Prevention (CDC).
To find out if there might be any association between adult circulating IGF-1 levels, birth weight, and the risk of developing type 2 diabetes, the team drew on data from 112,736 women and 68,354 men taking part in the UK Biobank study. It includes researchers from the National University of Singapore, Singapore; Tulane University, USA; Peking University, China; Harvard TH Chan School of Public Health, USA; and Brigham and Women’s Hospital and Harvard Medical School, USA.
The UK Biobank is a large population-based study, which recruited its 37 to 73-year-old participants between 2006 and 2010. It is tracking the potential impact of genetic and lifestyle factors on a wide range of common diseases of middle and old age.
At recruitment, participants provided social and demographic details, as well as information on their usual diet, lifestyle (smoking status, alcohol intake, sleep duration, and habitual physical activity), early life factors (birthweight and maternal smoking) and medical history. They also provided blood, urine, and saliva samples, and their height, weight, body mass index (BMI), body circumferences (waist, hip, and limbs), and skinfold thickness were measured.
Blood was checked for IGF-1, cholesterol, triglycerides, and an indicator of inflammation, C-reactive protein. Repeat measures of IGF-1 were available from 17,699 participants. Information on the development of type 2 diabetes was obtained from self-report, hospital records, and death certificates.
During an average monitoring period of nearly 10 years, 3,299 people developed type 2 diabetes. Participants with lower levels of IGF-1 tended to be older and more likely to live in a deprived area. They were also more likely to have lifestyle and clinical risk factors for diabetes.
A “clear inverse association” emerged between IGF-1 levels and type 2 diabetes: the lower the IGF-1 level, the higher was the risk of type 2 diabetes. Birthweight significantly altered this association, but only for those whose weight was 2.5 kg or more at birth, and only in men.
“Compared with those in the lowest 20% of IGF-1 levels, the odds of type 2 diabetes were 14% lower for those in the second-lowest 20%, and up to 36% lower for those in the highest 20% of IGF-1 levels. The findings held, irrespective of any genetic predisposition to birthweight,” write investigators.
Since this is an observational study, it cannot establish cause. However, the results echo those of other epidemiological studies, note authors, adding that prevention strategies are key. “Our findings highlight the importance of early-life risk factors in the development of the life course prevention strategies targeting IGF-1 and type 2 diabetes,” they recommend.