Thanh G N Ton1, W T Longstreth, Thomas Koepsell. 1. Neuroepidemiology Group, School of Public Health and Community Medicine, University of Washington, Seattle, WA, USA. thanhton@u.washington.edu
Abstract
BACKGROUND: We examined the risk of narcolepsy associated with active and passive smoking among genetically susceptible individuals. METHODS: We conducted a population-based case-control study in King County, Wash., USA. Between 2001 and 2005, we enrolled 67 cases through physicians and public outreach, and 95 controls through random-digit dialing. Subjects were aged between 18 and 50 years and positive for HLA DQB1*0602. All subjects were administered in-person interviews about their history of active and passive smoking. RESULTS: We observed an increased risk of narcolepsy associated with having lived with two or more household smokers (odds ratio, OR = 5.1; 95% confidence interval, CI: 1.6, 12.1); with a grandparent or a sibling who smoked (OR = 3.0; 95% CI: 1.1, 8.3); with a non-family household member who smoked (OR = 3.7; 95% CI: 1.6, 8.6); and with an unrelated smoker for 1-2 years (OR = 3.1; 95% CI: 1.0, 9.0). The risk of narcolepsy was not associated with exposure to smoke at work or with active smoking before age 21 or before age of narcolepsy onset. CONCLUSION: Passive smoking may be a risk factor for narcolepsy in subjects with HLA DQB1*0602. Future studies could help clarify whether passive smoking is an important etiologic component of narcolepsy among genetically susceptible individuals. 2008 S. Karger AG, Basel.
BACKGROUND: We examined the risk of narcolepsy associated with active and passive smoking among genetically susceptible individuals. METHODS: We conducted a population-based case-control study in King County, Wash., USA. Between 2001 and 2005, we enrolled 67 cases through physicians and public outreach, and 95 controls through random-digit dialing. Subjects were aged between 18 and 50 years and positive for HLA DQB1*0602. All subjects were administered in-person interviews about their history of active and passive smoking. RESULTS: We observed an increased risk of narcolepsy associated with having lived with two or more household smokers (odds ratio, OR = 5.1; 95% confidence interval, CI: 1.6, 12.1); with a grandparent or a sibling who smoked (OR = 3.0; 95% CI: 1.1, 8.3); with a non-family household member who smoked (OR = 3.7; 95% CI: 1.6, 8.6); and with an unrelated smoker for 1-2 years (OR = 3.1; 95% CI: 1.0, 9.0). The risk of narcolepsy was not associated with exposure to smoke at work or with active smoking before age 21 or before age of narcolepsy onset. CONCLUSION: Passive smoking may be a risk factor for narcolepsy in subjects with HLA DQB1*0602. Future studies could help clarify whether passive smoking is an important etiologic component of narcolepsy among genetically susceptible individuals. 2008 S. Karger AG, Basel.
Authors: W T Longstreth; Thanh G N Ton; Thomas Koepsell; Vivian H Gersuk; Audrey Hendrickson; Sarah Velde Journal: Sleep Med Date: 2008-11-13 Impact factor: 3.492