title: Group A Streptococcal Infections Are Associated With Increased Risk of Pediatric Neuropsychiatric Disorders: A Taiwanese Population-Based Cohort Study.
abstract: This study evaluated the association between group A streptococcal (GAS) infections and the risks of developing tic disorders, obsessive-compulsive disorder (OCD), and attention-deficit/hyperactivity disorder (ADHD).
  
  
  
  We conducted a follow-up cohort study in 2014 using Taiwan's National Health Insurance Research Database. The study cohort consisted of patients younger than 18 years with newly diagnosed GAS infection (ICD-9-CM codes 034 [streptococcal sore throat and scarlet fever] and 482.31 [pneumonia due to Streptococcus, group A]) from 2001 to 2010. All patients having GAS infection codes between 1996 and 2000 were excluded. We assessed the patients' risks of developing tic disorders, OCD, and ADHD (ICD-9-CM codes 300.3 [obsessive-compulsive disorders], 301.4 [obsessive-compulsive personality disorder], 307.2 [tic disorder, unspecified], and 314 [attention deficit disorder]) and compared these risks with those of a control cohort. The primary outcomes of this study were the overall neuropsychiatric disorder occurrence and the occurrence of separate subtypes.
  
  
  
  We examined 2,596 patients and 25,960 controls. The incidence of neuropsychiatric disorders in the GAS infection cohort (60.42 per 10,000 person-years) was significantly higher than that in the comparison cohort (49.32 per 10,000 person-years) (hazard ratio [HR] = 1.22; 95% CI, 1.00-1.49). The largest increased risk was for tic disorders (HR = 1.63; 95% CI, 1.02-2.62). Patients hospitalized for GAS infection had a 1.96-fold higher risk of neuropsychiatric disorders than did people without GAS infection (HR = 1.96; 95% CI, 1.23-3.12), and there was no difference in risk between outpatients with GAS infection and people without GAS infection (HR = 1.14; 95% CI, 0.92-1.41). Patients with moderate or high frequencies of GAS infection-related clinic visits had much higher risks of developing a neuropsychiatric disorder and, specifically, tic disorders and ADHD (all P values for trend < .05). These risks were not increased in patients with a low frequency of clinic visits.
  
  
  
  Our results confirmed an association between previous group A streptococcal infection and neuropsychiatric disorders.
authors.affiliation: Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.|College of Medicine, National Taiwan University, Taipei, Taiwan.|College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Han-Cheng
authors.initials: HC
authors.lastname: Wang
authors.affiliation: Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
authors.forename: Chi-Ieong
authors.initials: CI
authors.lastname: Lau
authors.affiliation: Management Office for Health Data, eDepartment of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan.|College of Medicine, gGraduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan.|Healthcare Service Research Center (HSRC), Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: Che-Chen
authors.initials: CC
authors.lastname: Lin
authors.affiliation: Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
authors.forename: Anna
authors.initials: A
authors.lastname: Chang
authors.affiliation: Professor, Graduate Institute of Clinical Medicine Science, College of Medicine, China Medical University, No. 2, Yuh-Der Rd, Taichung 40447, Taiwan. d10040@mail.cmuh.org.tw.
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Kao
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000453:epidemiology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000453:epidemiology*; D013290:Streptococcal Infections / Q000453:epidemiology*; D013624:Taiwan / Q000453:epidemiology; D013981:Tic Disorders / Q000453:epidemiology*