A total of 457 deaths from suicide were documented among the 253,033 participants: 221 in NHS (rate=6.3/100,000 person-years), 71 in NHS II (rate=4.3/100,000), and 165 in HPFS (rate=19.2/100,000). After multivariate adjustment, current smoking was associated with a higher suicide risk in all cohorts (Table 2). Compared to never smokers, the pooled multivariate RR of suicide was 1.15 (95% CI, 0.91–1.45) for former smokers and 2.69 (95% CI, 2.11, 3.42) for current smoker. The risk of suicide was higher as the number of CPD increased (Ptrend<.001), and was the highest among those who smoked ≥25 CPD (pooled multivariate RR=4.13; 95% CI, 2.96–5.78). Among former smokers, the risk of suicide was not associated with the number of CPD in the past (data not shown). Compared to those who smoked for less than 10 years, risks of suicide were not statistically significant among those who smoked for 10–19 years or ≥20 years. Age at the start of smoking was not associated with risk of suicide. Smoking cessation was not associated with risk of suicide (Ptrend=0.62), compared to never smokers. The pooled multivariate RR
