title: Association between Birth Characteristics and Cardiovascular Autonomic Function at Mid-Life.
abstract: BACKGROUND
  Low birth weight is associated with an increased risk of cardiovascular diseases in adulthood. As abnormal cardiac autonomic function is a common feature in cardiovascular diseases, we tested the hypothesis that low birth weight may also be associated with poorer cardiac autonomic function in middle-aged subjects.
  
  
  METHODS
  At the age of 46, the subjects of the Northern Finland Birth Cohort 1966 were invited to examinations including questionnaires about health status and life style and measurement of vagally-mediated heart rate variability (rMSSD) from R-R intervals (RRi) and spontaneous baroreflex sensitivity (BRS) in both seated and standing positions. Maternal parameters had been collected in 1965-1966 since the 16th gestational week and birth variables immediately after delivery. For rMSSD, 1,799 men and 2,279 women without cardiorespiratory diseases and diabetes were included and 902 men and 1,020 women for BRS. The analyses were adjusted for maternal (age, anthropometry, socioeconomics, parity, gestational smoking) and adult variables (life style, anthropometry, blood pressure, glycemic and lipid status) potentially confounding the relationship between birth weight and autonomic function.
  
  
  RESULTS
  In men, birth weight correlated negatively with seated (r = -0.058, p = 0.014) and standing rMSSD (r = -0.090, p<0.001), as well as with standing BRS (r = -0.092, p = 0.006). These observations were verified using relevant birth weight categories (<2,500 g; 2,500-3,999 g; ≥4,000 g). In women, birth weight was positively correlated with seated BRS (r = 0.081, p = 0.010), but none of the other measures of cardiovascular autonomic function. These correlations remained significant after adjustment for potential confounders (p<0.05 for all).
  
  
  CONCLUSIONS
  In men, higher birth weight was independently associated with poorer cardiac autonomic function at mid-life. Same association was not observed in women. Our findings suggest that higher, not lower, birth weight in males may contribute to less favourable cardiovascular autonomic regulation and potentially to an elevated cardiovascular risk in later life.
authors.affiliation: Research Unit of Internal Medicine, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
authors.forename: Nelli
authors.initials: N
authors.lastname: Perkiömäki
authors.affiliation: Center for Life Course Health Research, University of Oulu, Oulu, Finland.|Unit of Primary Health Care, Oulu University Hospital, Oulu, Finland.
authors.forename: Juha
authors.initials: J
authors.lastname: Auvinen
authors.affiliation: Research Unit of Internal Medicine, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
authors.forename: Mikko P
authors.initials: MP
authors.lastname: Tulppo
authors.affiliation: Physiological Signal Analysis Team, Center for Machine Vision and Signal Analysis, University of Oulu, Oulu, Finland.
authors.forename: Arto J
authors.initials: AJ
authors.lastname: Hautala
authors.affiliation: Research Unit of Internal Medicine, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
authors.forename: Juha
authors.initials: J
authors.lastname: Perkiömäki
authors.affiliation: Center for Life Course Health Research, University of Oulu, Oulu, Finland.
authors.forename: Ville
authors.initials: V
authors.lastname: Karhunen
authors.affiliation: Center for Life Course Health Research, University of Oulu, Oulu, Finland.|Unit of Primary Health Care, Oulu University Hospital, Oulu, Finland.
authors.forename: Sirkka
authors.initials: S
authors.lastname: Keinänen-Kiukaanniemi
authors.affiliation: NordLab Oulu, Medical Research Center Oulu, Oulu University Hospital and Department of Clinical Chemistry, University of Oulu, Finland.
authors.forename: Katri
authors.initials: K
authors.lastname: Puukka
authors.affiliation: NordLab Oulu, Medical Research Center Oulu, Oulu University Hospital and Department of Clinical Chemistry, University of Oulu, Finland.
authors.forename: Aimo
authors.initials: A
authors.lastname: Ruokonen
authors.affiliation: Center for Life Course Health Research, University of Oulu, Oulu, Finland.|Unit of Primary Health Care, Oulu University Hospital, Oulu, Finland.|Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment & Health, School of Public Health, Imperial College London, London, United Kingdom.|Biocenter Oulu, University of Oulu, Oulu, Finland.
authors.forename: Marjo-Riitta
authors.initials: MR
authors.lastname: Järvelin
authors.affiliation: Research Unit of Internal Medicine, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
authors.forename: Heikki V
authors.initials: HV
authors.lastname: Huikuri
authors.affiliation: Research Unit of Internal Medicine, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
authors.forename: Antti M
authors.identifier: http://orcid.org/0000-0002-1160-493X
authors.initials: AM
authors.lastname: Kiviniemi
mesh_terms: D000704:Analysis of Variance; D001341:Autonomic Nervous System / Q000503:physiopathology*; D017704:Baroreflex; D015415:Biomarkers; D001724:Birth Weight; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000209:etiology*; D002319:Cardiovascular System / Q000294:innervation* / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012307:Risk Factors
chemical_list: D015415:Biomarkers