BIRTH-WEIGHT OF OFFSPRING AND MORTALITY IN THE RENFREW AND PAISLEY STUDY - PROSPECTIVE OBSERVATIONAL STUDY

Objective: To investigate the association between birth weight of offs pring and mortality among fathers and mothers in the west of Scotland. Design: Prospective observational study. Participants: 794 married co uples in Renfrew district of the west of Scotland.Main outcome measure s: Mortality from all causes and from cardiovascular disease over 15 y ear follow up. Results: Women who had heavier babies were taller, had higher body mass index and better lung function, and were less likely to be smokers than mothers of lighter babies. Fathers of heavier babie s were taller and less likely to be smokers than fathers of lighter ba bies. Mortality was inversely related to offspring's birth weight for both mothers (relative rate for a 1 kg lower birth weight 1.82 (95% co nfidence interval 1.23 to 2.70)) and fathers (relative rate 1.35 (1.03 to 1.79)). For mortality from cardiovascular disease, inverse associa tions were seen for mothers (2.00 (1.18 to 3.33)) and fathers (1.52 (1 .03 to 2.17)). Adjustment for blood pressure, plasma cholesterol, body mass index, height, social class, area based deprivation category, sm oking, lung function, angina, bronchitis, and electrocardiographic evi dence of ischaemia had little effect on these risk estimates, although levels of statistical significance were reduced. Conclusions: Birth w eight of offspring was related inversely to mortality, from all causes and cardiovascular disease, in this cohort. The strength of this asso ciation was greater than would have been expected by the degree of con cordance of birth weights across generations, but an extensive range o f potential confounding factors could not account for the association. Mortality is therefore influenced by a factor related to birth weight that is transmissible across generations.