Smoking and the risk of suicidal behavior: a prospective study of a community sample.

BACKGROUND: A link between cigarette smoking and suicidal behavior has been reported in clinical and epidemiological studies. OBJECTIVE: To examine the association between smoking and suicidal thoughts or attempt in a longitudinal study, in which proximate status of smoking and psychiatric disorders in relation to timing of suicidal behaviors is taken into account. DESIGN: A longitudinal study of young adults interviewed initially in 1989, with repeated assessments over a 10-year follow-up. SETTING AND PARTICIPANTS: The sample was selected from a large health maintenance organization representing the geographic area, except for the extremes of the socioeconomic range. The response rate at each follow-up (3, 5, and 10 years after baseline) exceeded 91%. MAIN OUTCOME MEASURES: Relative risk of occurrence of suicidal behaviors during follow-up intervals by status of smoking and psychiatric disorders at the start of the interval, estimated by generalized estimating equations with repeated measures. The National Institute of Mental Health Diagnostic Interview Schedule was used at baseline and at each reassessment. RESULTS: Current daily smoking, but not past smoking, predicted the subsequent occurrence of suicidal thoughts or attempt, independent of prior depression and substance use disorders (adjusted odds ratio, 1.82; 95% confidence interval, 1.22-2.69). Additionally, current daily smoking, but not past smoking, predicted the subsequent occurrence of suicidal thoughts or attempt, adjusting for suicidal predisposition, indicated by prior suicidality, and controlling for prior psychiatric disorders (adjusted odds ratio, 1.74; 95% confidence interval, 1.17-2.54). CONCLUSIONS: The biological explanation of the finding that current smoking is associated with subsequent suicidal behavior is unclear. Recent observations of lower monoamine oxidase activity (which may play a role in central nervous system serotonin metabolism) in current smokers but not ex-smokers might provide clues, but interpretations should proceed cautiously.

Partial PTSD versus full PTSD: an empirical examination of associated impairment.

BACKGROUND: Partial PTSD, employed initially in relation to Vietnam veterans, has been recently extended to civilian victims of trauma. We examined the extent to which partial PTSD is distinguishable from full DSM-PTSD with respect to level of impairment. METHOD: A representative sample of 2181 persons was interviewed by telephone to record lifetime traumatic events and to assess DSM-IV PTSD criteria. Partial PTSD was defined as > or = 1 symptom in each of three symptom groups (criteria B, C and D) and duration of > or = 1 month. Impairment in persons with PTSD and partial PTSD was measured by number of work-related and personal disability days during the 30-day period when the respondent was most upset by the trauma. RESULTS: Compared to exposed persons with neither PTSD nor partial PTSD, increment in work-loss days associated with PTSD was 11.4 (S.E. =0.6) days and with partial PTSD, 3.3 (S.E. =0.4) days (adjusted for sex, education and employment). Similar disparities were found across other impairment indicators. Persons who fell short of PTSD criteria by one symptom of avoidance and numbing reported an increment of 5.0 (S.E. =0.7) work-loss days, 6.0 fewer than full PTSD. PTSD was associated with excess impairment, controlling for number of symptoms. A significantly lower proportion of persons with partial PTSD than full PTSD experienced symptoms for more than 2 years. A lower proportion of persons with partial PTSD than full PTSD had an etiologic event of high magnitude. CONCLUSIONS: PTSD identifies the most severe trauma victims, who are markedly distinguishable from victims with subthreshold PTSD.

Posttraumatic stress disorder and the incidence of nicotine, alcohol, and other drug disorders in persons who have experienced trauma.

BACKGROUND: We examine whether exposure to traumatic events increases the risk for nicotine dependence or alcohol or other drug use disorders, independent of posttraumatic stress disorder (PTSD). METHODS: Data come from a longitudinal epidemiologic study of young adults in southeast Michigan. Prospective data covering a 10-year period and retrospective lifetime data gathered at baseline were used to estimate the risk for onset of substance use disorders in persons with PTSD and in persons exposed to trauma without PTSD, compared with persons who have not been exposed to trauma. The National Institute of Mental Health Diagnostic Interview Schedule for DSM-III-R was used. Logistic regression was used to analyze the prospective data, and Cox proportional hazards survival analysis with time-dependent variables was applied to the lifetime data. RESULTS: The prospective and retrospective data show an increased risk for the onset of nicotine dependence and drug abuse or dependence in persons with PTSD, but no increased risk or a significantly (P =.004) lower risk (for nicotine dependence, in the prospective data) in persons exposed to trauma in the absence of PTSD, compared with unexposed persons. Exposure to trauma in either the presence or the absence of PTSD did not predict alcohol abuse or dependence. CONCLUSIONS: The findings do not support the hypothesis that exposure to traumatic events per se increases the risk for substance use disorders. A modestly elevated risk for nicotine dependence might be an exception. Posttraumatic stress disorder might be a causal risk factor for nicotine and drug use disorders or, alternatively, the co-occurrence of PTSD and these disorders might be influenced by shared risk factors other than traumatic exposure.

Opiate pharmacology and individual differences. I. Psychophysical pain measurements.

A new electric stimulation pain assessment technique using the Tursky electrode and a non-parametric analysis of subjects ratings was found sensitive to aspirin, morphine and opiate antagonists in a series of double-blind cross-over trials in normal adults. Stable individual differences in pain sensitivity (off medication) were maintained on two testing sessions 7 months apart. Older individuals were less pain sensitive than younger individuals. Men were more insensitive than women under age 30. Together, these results suggest the empiric usefulness of this pain measurement technique.

Opiate pharmacology and individual differences. II. Somatosensory evoked potentials.

Somatosensory evoked potentials (EPs) to stimuli ranging from barely perceptible to painful were recorded in 153 normal adults. Reliability of amplitude and amplitude/intensity slopes were demonstrated in 29 individuals tested twice, two or more weeks apart. In randomized, double-blind placebo controlled trials, both aspirin and morphine significantly diminished N120 component at high stimulus intensities. Age, sex and pharmacological effects paralleled those found with psychophysical techniques in part I of this study.