Biomedical subjects

Lisa Heavey

Publications and source records attributed to Lisa Heavey.

3 recordsLinked to original sources

PubMed2004

Rate of first recorded diagnosis of autism and other pervasive developmental disorders in United Kingdom general practice, 1988 to 2001.

BACKGROUND: There has been concern that the incidence of autism and other pervasive developmental disorders (PDDs) is increasing. Previous studies have been smaller, restricted to autism (excluding other pervasive developmental disorders such as Asperger's syndrome), included boys only, or have not been based on a national sample. We investigated time trends in the rates of diagnosis of pervasive developmental disorders. METHODS: We analysed the rates of first diagnosis of pervasive developmental disorders among people registered with a practice contributing to the United Kingdom General Practice Research Database during the period 1988 to 2001. We included 1410 cases from over 14 million person-years of observation. The main outcome measures were rates of diagnosis of pervasive developmental disorders by year of diagnosis, year of birth, gender and geographical region. RESULTS: The rate increased progressively from 0.40/10,000 person-years (95% CI 0.30 to 0.54) in 1991 to 2.98/10,000 (95% CI 2.56 to 3.47) in 2001. A similar change occurred in the age standardised incidence ratios, from 35 (95% CI: 26-47) in 1991 to 365 (95% CI: 314-425) in 2001. The temporal increase was not limited to children born during specific years nor to children diagnosed in a specific time period. The rate of diagnosis of PDDs other than autism rose from zero for the period 1988-1992 to 1.06/10,000 person-years in 2001. The rate of diagnosis of autism also increased but to a lesser extent. There was marked geographical variation in rates, with standardised incidence ratios varying from 66 for Wales to 141 for the South East of England. CONCLUSIONS: Better ascertainment of diagnosis is likely to have contributed to the observed temporal increase in rates of diagnosis of PDD, but we cannot exclude a real increase.

Asperger Syndrome↗

PubMed2004

Validation of the diagnosis of autism in general practitioner records.

BACKGROUND: We report on the validity of the computerized diagnoses of autism in a large case-control study investigating the possible association between autism and the measles, mumps and rubella vaccine in the UK using the General Practitioner Research Database (GPRD). We examined anonymized copies of all relevant available clinical reports, including general practitioners' (GP) notes, consultant, speech therapy and educational psychologists reports, on 318 subjects born between 1973 and 1997 with a diagnosis of autism or a related disorder recorded in their electronic general practice record. METHODS: Data were abstracted to a case validation form allowing for the identification of developmental symptoms relevant to the diagnosis of pervasive developmental disorders (PDDs). Information on other background clinical and familial features was also abstracted. A subset of 50 notes was coded independently by 2 raters to derive reliability estimates for key clinical characteristics. RESULTS: For 294 subjects (92.5%) the diagnosis of PDD was confirmed after review of the records. Of these, 180 subjects (61.2%) fulfilled criteria for autistic disorder. The mean age at first recording of a PDD diagnosis in the GPRD database was 6.3 years (SD = 4.6). Consistent with previous estimates, the proportion of subjects experiencing regression in the course of their development was 19%. Inter-rater reliability for the presence of a PDD diagnosis was good (kappa =.73), and agreement on clinical features such as regression, age of parental recognition of first symptoms, language delay and presence of epilepsy was also good (kappas ranging from.56 to 1.0). CONCLUSIONS: This study provides evidence that the positive predictive value of a diagnosis of autism recorded in the GPRD is high.

Age of Onset↗

PubMedDate not supplied

MMR vaccination and pervasive developmental disorders: a case-control study.

BACKGROUND: Concern that measles-mumps-rubella (MMR) vaccination might cause autism has led to a fall in vaccine coverage. We investigated whether MMR vaccination is associated with an increased risk of autism or other pervasive developmental disorders. METHODS: We did a matched case-control study using the UK General Practice Research Database. Cases were people born in 1973 or later who had first recorded diagnosis of pervasive developmental disorder while registered with a contributing general practice between 1987 and 2001. Controls were matched on age, sex, and general practice. FINDINGS: 1294 cases and 4469 controls were included. 1010 cases (78.1%) had MMR vaccination recorded before diagnosis, compared with 3671 controls (82.1%) before the age at which their matched case was diagnosed. After adjustment for age at joining the database, the odds ratio for association between MMR and pervasive developmental disorder was 0.86 (95% CI 0.68-1.09). Findings were similar when restricted to children with a diagnosis of autism, to those vaccinated with MMR before the third birthday, or to the period before media coverage of the hypothesis linking MMR with autism. INTERPRETATION: Our findings suggest that MMR vaccination is not associated with an increased risk of pervasive developmental disorders.

Asperger Syndrome↗