Nitsch D, Sandling JK, Byberg L, Larsson A, Tuvemo T, Syvänen AC, Koupil I, Leon DA.
SourceFaculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, London, UK. dorothea.nitsch@lshtm.ac.uk
Abstract
BACKGROUND: The aim was to identify determinants (biomedical and social characteristics of children and their parents) of cystatin C levels in healthy children drawn from a population sample.
STUDY DESIGN: Cross-sectional study.
SETTING & PARTICIPANTS: 425 pairs of consecutive full siblings born 1987-1995 in Uppsala were identified using the Swedish Medical Birth Registry and invited with their parents for examination in 2000-2001.
OUTCOME: Serum cystatin C level was log-transformed and analyzed using random-effects models.
MEASUREMENTS: The examination in parents and children consisted of a nonfasting blood sample, anthropometry, and questionnaires about lifestyle and socioeconomic position. Tanner stage was used for assessment of pubertal status.
RESULTS: In age-, height-, and body mass index-adjusted analyses, cystatin C level increased by 2.6% (95% CI, 0.3%-4.8%) higher in Tanner stage 2 vs 1 girls, and 1.6% (95%CI, 0.2%-3.1%) lower in boys than girls. For every 10% increase in maternal cystatin C level, offspring cystatin C level increased by 3.0% (95% CI, 2.2%-3.8%); the equivalent effect for paternal cystatin C level was 2.1% (95% CI, 1.3%-2.9%). Lower maternal education was associated with a 2.4% (95% CI, 0.3%-4.6%) higher cystatin C level in their offspring.
LIMITATIONS: Cross-sectional study design, missing cystatin C values for subset of parents, lack of urinary measurements, no gold-standard measurement of glomerular filtration rate.
CONCLUSIONS: There are intergenerational associations of cystatin C level in families in line with previous reports of heritability of kidney disease. Lower maternal education is associated with higher cystatin C levels in their children. Further studies of healthy children are needed to explore the biological mechanisms for these findings. If cystatin C is measured, these studies will need to record pubertal stages.
