[Show abstract][Hide abstract] ABSTRACT: Findings from previous epidemiological studies are inconclusive, though they suggest nonsteroidal anti-inflammatory drug (NSAID) use is associated with a reduction in breast cancer risk. In addition, animal studies report that NSAIDs inhibit mammary tumor development. The association between NSAID use and breast cancer risk was evaluated using a case-control study design. Cases were a random sample of women diagnosed with a first primary cancer of the breast, aged 25-74 years, identified through the Ontario Cancer Registry, and diagnosed between July 1996 and September 1998. Controls were an age-matched random sample of the female population of Ontario. Cases (n = 3133) and controls (n = 3062) completed a mailed questionnaire with information on their past use of NSAID and other medications, as well as many risk factors thought to be associated with breast cancer. Multivariate logistic regression analysis was used to obtain adjusted odds ratio (OR) estimates. Use of any NSAID medication (daily use for > or =2 months) was found to be associated with a significant 24% reduction in breast cancer risk (OR = 0.76; 95% confidence interval: 0.66, 0.88). The reduced risk was strongest for use lasting > 8 years, compared with nonusers (OR = 0.68; 95% confidence interval: 0.54, 0.86). No marked trends were observed for time since first use or last use or age at first use. Our results suggest a reduction in breast cancer risk associated with any regular NSAID use. NSAID use is a modifiable factor, and any protective effect attributed to its use could be of great public health importance.
[Show abstract][Hide abstract] ABSTRACT: Experimental and epidemiologic studies suggest that antidepressant medication use may be associated with breast cancer risk. This hypothesis was investigated using a population-based case-control study; cases diagnosed in 1995-1996 were identified using the Ontario Cancer Registry, and controls were randomly sampled from an Ontario Ministry of Finance database. Data were collected using a self-administered questionnaire, and multivariate logistic regression was used to estimate odds ratios and 95% confidence intervals. Adjusted odds ratio estimates ranged from 0.7 to 0.8 and were not statistically significant for "ever" use of antidepressants, tricyclics, and selective serotonin reuptake inhibitors. Compared with no antidepressant use, use of tricyclic antidepressants for greater than 2 years' duration was associated with an elevated risk of breast cancer (odds ratio (OR) = 2.1, 95% confidence interval (CI): 0.9, 5.0). Of the six most commonly reported antidepressant medications, only paroxetine use was associated with an increase in breast cancer risk (OR = 7.2, 95% CI: 0.9, 58.3). Results from this study do not support the hypothesis that "ever" use of any antidepressant medications is associated with breast cancer risk. Use of tricyclic medications for greater than 2 years, however, may be associated with a twofold elevation, and use of paroxetine may be associated with a substantial increase in breast cancer risk.
American Journal of Epidemiology 06/2000; 151(10):951-7. · 4.78 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Self-reported medication histories obtained in pharmacoepidemiologic case-control studies are subject to non-differential misclassification and to recall bias. The accuracy of self-reported antidepressant medication use has never been evaluated, but it is important in light of the hypothesis that antidepressant medications may be associated with cancer risk.
Within a case-control study of several cancer sites, we compared self-reported antidepressant medication use with antidepressant use recorded in physicians' records. All female cases (n = 147) and controls (n = 119) who reported antidepressant medication use, and a 10% random sample (n = 114) of those who reported no antidepressant use, were asked to provide consent to contact, and the name(s) of their physician(s). These physicians completed a data abstraction form including information on antidepressant prescriptions recorded in patients' medical records.
Substantial agreement was found between subject- and physician-reported antidepressant medication use (kappa = 0.60 [95% confidence interval (CI), 0.47-0.74]; agreement = 80%), and use of specific antidepressant medications (agreement ranged from 82 to 100%), while moderate agreement was observed for duration of use (weighted kappa = 0.56 (95% CI, 0.32-0.79)), and date of first use [weighted kappa = 0.48 (95% CI, 0.23-0.72)]. The level of agreement did not differ markedly between cases and controls, except for duration of use, where agreement was somewhat greater for cases.
The similar level of agreement among cases and controls suggests that differential misclassification (e.g., recall bias) is unlikely in the reporting of most aspects of antidepressant medication use by women. Furthermore, the overall accurate self-reporting of antidepressant use suggests that there should be minimal non-differential antidepressant exposure misclassification.
Annals of Epidemiology 08/1999; 9(5):283-9. · 2.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Do antidepressants cause, promote, or inhibit cancers?
To review all human and experimental studies that examined the association of antidepressants with cancer or the effect of antidepressants on neoplastic growth.
A search was conducted of MEDLINE for relevant articles published in English between 1976 and 1993.
Four human studies and nine experimental models were found. The human studies showed a transiently statistically significant positive association between amitriptyline and liver cancer and a negative association with pancreatic cancer; and that the antidepressants amitriptyline, nortriptyline, desipramine, and phenelzine may increase risk of breast cancer. Results of the experimental studies differed depending on which antidepressants were examined and which model was used. Amitriptyline was found to promote tumour growth, fluoxetine and clomipramine were reported to be both tumour promoters and antineoplastic agents, and imipramine and citalopram both demonstrated antineoplastic properties.
Further epidemiologic studies in humans are needed to determine which antidepressants cause, promote, or inhibit cancers.
Journal of Clinical Epidemiology 12/1995; 48(11):1407-12. · 5.48 Impact Factor