Morbidity risk of psychiatric disorders among the first degree relatives of schizophrenia patients in Taiwan.
This study aimed to assess the boundaries of the schizophrenia spectrum and whether inclusion of such phenotypes increases power for linkage analysis of schizophrenia. Participants were 234 first degree relatives (FDRs) of 94 schizophrenia probands in Northern Taiwan who completed a direct interview using the Diagnostic Interview for Genetic Studies (DIGS). Based on best estimate diagnosis, the morbidity risk in the relatives for schizophrenia was 2.5 percent (Weinberg's shorter method) or 3.9 percent (Kaplan-Meier estimate). Depending on the stringency of diagnosis, lifetime prevalence was 2.6 percent to 4.7 percent for schizotypal personality disorder, 3.4 percent to 8.6 percent for paranoid personality disorder, and 1.3 percent to 3.4 percent for schizoid personality disorder. These figures are significantly higher than the corresponding figures in the general population. However, none of the recurrence risk ratio for any spectrum that included both schizophrenia and a personality disorder (3.0 to 5.9) was greater than that of schizophrenia alone (9.3 to 14.4). Thus, including schizophrenia-related personality disorders in the spectrum did not increase power for linkage analysis of schizophrenia.
Chang
Ching-Jui
CJ
Department of Psychiatry, College of Medicine, National Taiwan University, Taipei.
Chen
Wei J
WJ
Liu
Shi K
SK
Cheng
Joseph J
JJ
Yang
Wen-Chen Ou
WC
Chang
Hung-Jung
HJ
Lane
Hsien-Yuan
HY
Lin
Shi-Kwang
SK
Yang
Tien-Wei
TW
Hwu
Hai-Gwo
HG
D000293:Adolescent; D000328:Adult; D002874:Chromosome Mapping; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000209:etiology* / Q000235:genetics*; D008875:Middle Aged; D009017:Morbidity; D010641:Phenotype; D012307:Risk Factors; D012557:Schizoid Personality Disorder / Q000235:genetics* / Q000523:psychology*; D012559:Schizophrenia / Q000150:complications* / Q000235:genetics*; D013624:Taiwan