Helen Coo | PubMed Health

PubMed2007

Trends in special education code assignment for autism: implications for prevalence estimates.

There is considerable controversy over reasons for observed increases in the prevalence of autism spectrum disorders. We examined trends in British Columbia education database coding of children with autism from 1996 to 2004. There was a significant linear increase in autism prevalence. The proportion of children identified by age 6 increased significantly from 1996 to 1999. When we calculated prevalence assuming onset prior to age 3, previously unidentified cases, particularly among girls in 1996 and 1997, accounted for substantial increases in estimated prevalence. The magnitude of under-identification decreased from 1996 to 2000, and rose slightly in 2001. Analyses of prevalence trends must take into account effects of earlier age at identification and inclusion of previously undetected cases on prevalence estimates.

Age Factors↗

PubMed2003

Quality of sleep and health-related quality of life in haemodialysis patients.

BACKGROUND: Sleep complaints are common in haemodialysis patients. In the general population, insomnia impacts negatively on health-related quality of life (HRQoL). The objective of this study was to examine the association between quality of sleep and HRQoL in haemodialysis patients independent of known predictors of HRQoL. METHODS: Quality of sleep was measured using the Pittsburgh Sleep Quality Index (PSQI) and HRQoL was measured using the Medical Outcomes Study 36-item Short Form (SF-36) in 89 haemodialysis patients. RESULTS: Sixty-three (71%) subjects were 'poor sleepers' (global PSQI >5). The SF-36 mental component summary (MCS) and physical component summary (PCS) correlated inversely with the global PSQI score (MCS, r = -0.28, P < 0.01; PCS, r = -0.45, P < 0.01). The PCS score also correlated with age (r = -0.24, P = 0.02), haemoglobin (r = 0.21, P = 0.048) and comorbidity (r = -0.40, P < 0.01), and mean PCS was lower in depressed subjects (26.2 vs 35.9, P = 0.02). Subjects with global PSQI >5 had a higher prevalence of depression, lower haemoglobin and lower HRQoL in all SF-36 domains. The global PSQI score was a significant independent predictor of the MCS and PCS after controlling for age, sex, haemoglobin, serum albumin, comorbidity and depression in multivariate analysis. CONCLUSIONS: Poor sleep is common in dialysis patients and is associated with lower HRQoL. We hypothesize that end-stage renal disease directly influences quality of sleep, which in turn impacts on HRQoL.

Analysis of Variance↗