In 4,901 members of the 1958 British birth cohort, 26.3% experienced obesity at some point between ages 7 and 62. Ever being obese did not predict NT-proBNP, but men with obesity history had 11% higher cardiac troponin I (hs-cTnI). Duration mattered most: hs-cTnI rose steadily with each obese year, while NT-proBNP and GDF-15 stayed flat until roughly 25 years of obesity, then climbed 1.8% and 0.8% per additional year, after adjustment for early-life, cardiometabolic, behavioural and socioeconomic factors.
The threshold pattern is the notable part. It suggests the heart tolerates obesity for a couple of decades before stress signals emerge, which fits the idea that cumulative exposure, not a single BMI snapshot, drives cardiovascular risk. Practically, it favours preventing obesity early or reversing it before the 25-year mark, though the study cannot show that weight loss lowers these markers. Biomarkers like NT-proBNP and troponin predict heart failure and cardiovascular death, but the study measured the markers, not clinical events. Limitations include one cohort of a single birth year and country, a largely white population, measurement at one age, and observational design, so residual confounding remains possible. The attenuation of GDF-15 after adjusting for current cardiometabolic status also hints that blood pressure, glucose and lipids may partly mediate the effect. This is a preprint that has not yet been peer reviewed, so the estimates may shift. Overall it is a useful, incremental refinement of the duration-of-obesity literature, not a paradigm shift.