Personality and depression.

OBJECTIVE: To examine the implications of the association between personality and depression for the understanding, assessment, and treatment of major depression. METHOD: A broad range of peer-reviewed manuscripts relevant to personality and depression was reviewed. Particular emphasis was placed on etiology, stability, diagnosis, and treatment implications. RESULTS: Personality features in depressed samples reliably differ from those of healthy samples. The associations between personality and depression are consistent with a variety of causal models; these models can best be compared through longitudinal research. Research demonstrates that attention to personality features can be useful in diagnosis and treatment. Indeed, personality information has been on the forefront of recent efforts to advance the current diagnostic classification system. Moreover, personality dimensions have shown recent promise in the prediction of differential treatment outcome. For example, neuroticism is associated with preferential response to pharmacotherapy rather than psychotherapy. CONCLUSIONS: Consideration of personality features is crucial to the understanding and management of major depression.

Lung cancer and arsenic exposure in drinking water: a case-control study in northern Chile.

In some Chilean cities, levels of arsenic (As) in drinking water reached 800 (micrograms/L between 1950 and 1970, while current levels are 40 (micrograms/L. To evaluate the causal role of this exposure in lung and bladder cancers, we conducted a case-control study in Regions I, II, and III of the country. From 1994 to 1996, cases diagnosed as lung cancer and two hospital controls were entered in the study; one control was a patient with a cancer, while the other was a patient without cancer, both conditions unrelated to As. Controls were matched with cases by age and sex. A standard survey containing questions about residence, employment, health history, was administered to study subjects. Data on As concentrations in water were obtained from records of the municipal water companies. A total of 151 lung cancer cases and 419 controls (167 with cancer and 242 without cancer) were enrolled. Median level of lifetime As exposure was significantly higher among cases, with a clear dose-response relationship between mean As exposure levels, with an OR (95% CI) of: 1, 1.7 (0.5-5.1), 3.9 (1.2-13.4), 5.5 (2.2-13.5), and 9.0 (3.6-22) for strata one to five respectively. This study provides new evidence that As in drinking water can cause internal cancers and gives an estimate of the form of this relationship.

Sudden unexpected death in epileptics following sudden, intense, increases in geomagnetic activity: prevalence of effect and potential mechanisms.

Abrupt, intense increases in global geomagnetic activity during the local night may precipitate a significant proportion of sudden unexpected (or unexplained) deaths (SUD) in epileptics. Over a 2-year period SUD in healthy chronic epileptic rats occurred when the average daily geomagnetic activity exceeded 50 nT (nanoTesla) and suddenly began during local night. Other experiments demonstrated that epileptic rats displayed more spontaneous seizures per night if there had been sudden increases in geomagnetic activity. Analyses of previously published data indicated that the number of SUDs/month in a population of human epileptics was positively associated with the number of days/month when the average geomagnetic activity exceeded 50 nT. The results support the hypothesis that suppression of the nocturnal concentrations of the endogenous anticonvulsant melatonin by sudden increases in geomagnetic activity may encourage fatal cardiac arrhythmias by uncoupling the insular/amygdaloid-paraventricular hypothalamic-solitary nucleus pathways.