Paternal age and schizophrenia: a population based cohort study.
OBJECTIVE
To investigate the association of paternal age at conception with the risk of offspring developing schizophrenia.


METHODS
A population based cohort study.


METHODS
Sweden.


METHODS
754,330 people born in Sweden between 1973 and 1980 and still alive and resident in Sweden at age 16 years.


METHODS
Hospital admission with schizophrenia or non-schizophrenic, non-affective psychosis.


RESULTS
After adjustment for birth related exposures, socioeconomic factors, family history of psychosis, and early parental death the overall hazard ratio for each 10 year increase in paternal age was 1.47 (95% confidence interval 1.23 to 1.76) for schizophrenia and 1.12 (0.98 to 1.29) for non-schizophrenic non-affective psychosis. This association between paternal age and schizophrenia was present in those with no family history of the disorder (hazard ratio for each 10 year increase in paternal age 1.60, 1.32 to 1.92), but not in those with a family history (0.91, 0.44 to 1.89) (P = 0.04 for interaction).


CONCLUSIONS
Advancing paternal age is an important independent risk factor for schizophrenia. The stronger association between paternal age and schizophrenia in people without a family history provides further evidence that accumulation of de novo mutations in paternal sperm contributes to the overall risk of schizophrenia.
Sipos
Attila
A
Academic Unit of Psychiatry, Cotham House, University of Bristol BS6 6JL.
Rasmussen
Finn
F
Harrison
Glynn
G
Tynelius
Per
P
Lewis
Glyn
G
Leon
David A
DA
Gunnell
David
D
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D001724:Birth Weight; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008423:Maternal Age; D008875:Middle Aged; D010331:Paternal Age; D010375:Pedigree; D016016:Proportional Hazards Models; D012307:Risk Factors; D012559:Schizophrenia / Q000453:epidemiology / Q000209:etiology* / Q000235:genetics; D012621:Seasons; D013548:Sweden / Q000453:epidemiology