The results section of the actual article:
Quote:
Six-hundred seventy-three individuals from 375 families were analyzed. Cases (n = 356) included 338 probands, 8 siblings, 7 extended relatives, 2 children, and 1 parent. Controls (n = 317) included 289 siblings, 10 parents, 10 spouses or other unrelated controls, 6 extended relatives, and 2 children. Two hundred thirty-five case subjects (66.0%) were male, whereas 139 controls (43.9%) were male. The mean ± SD AAE was 66.1 ± 10.7 years in cases and 63.7 ± 12.3 years in controls. Cases had a mean ± SD age at onset of 58.1 ± 11.6 years and a mean disease duration of 8.0 years. Because individuals with PD were more likely than unaffected relatives to be male and older at examination, sex and AAE were considered important confounders in our analyses.
Exposure histories were not obtained for 8.0% of participants for smoking, 5.9% for caffeine, and 5.3% for NSAIDs. Data from individuals with a missing exposure history were excluded from analyses for the relevant factor. Reported exposure histories were correlated as follows: smoking and caffeine, r = 0.19; smoking and NSAIDs, r = 0.05; and caffeine and NSAIDs, r = 0.10. Given these modest correlations, models with multiple exposures were valid.
Results from models examining associations of smoking while controlling for AAE and sex are shown in Table 1. Individuals with PD were 0.56 times as likely to report ever smoking and 0.30 times as likely to report current smoking compared with unaffected relatives. Dosage, duration, and intensity presented ORs indicative of inverse relationships between PD and smoking with significance at most exposure levels. Dose-response associations were detected with increasing status, dosage, duration, and intensity (P<.005). Patterns remained significant after truncating exposure at 10 and 20 years before the reference age (Table 1) and adjusting for caffeine and NSAIDs (data not shown). Even after applying the conservative Bonferroni correction for multiple testing, most associations and trends in ORs for smoking remained significant.
Caffeinated coffee associations with PD relative to never consuming it were assessed while controlling for AAE and sex. When truncating exposure at the reference age, a significant dose response for intensity (trend P = .05) was observed. When truncating exposure at 10 years before the reference age, high dosage (>2.0 cups/d) was significantly inversely associated with PD (OR = 0.64; 95% confidence interval, 0.42-0.99), and increasing dosage showed a significant trend in ORs (P = .05). No significant associations were observed after truncating exposure at 20 years before the reference age or adjusting for smoking and NSAIDs (data not shown).
Overall caffeine associations with PD compared with never consuming it were also assessed while controlling for AAE and sex. These results are presented in Table 2. Case subjects were neither more nor less likely than controls to report ever consuming caffeine. However, a significant inverse association with PD at high dosage and significant inverse gradients for dosage and intensity were detected. The significant inverse gradient for dosage persisted after truncating exposure at 10 and 20 years before the reference age. The trends in ORs for dosage and intensity were nearly significant after adjusting for AAE, sex, smoking, and NSAIDs (trend P = .06 for both), but the significant trends shown in Table 2 did not withstand the conservative Bonferroni correction (trend P = .08 for dosage and trend P = .09 for intensity after Bonferroni correction).
Most users of NSAIDs reported a current exposure of relatively short duration, so assessment of status and exposure truncation before the reference age was not possible. No significant associations between NSAIDs and PD were detected (Table 3). There were also no significant associations between nonaspirin NSAIDs and PD (data not shown). Adjustment for smoking and caffeine did not change these results (data not shown).
Title and authors - this was in Archives of Neurology
Quote:
Smoking, Caffeine, and Nonsteroidal Anti-inflammatory Drugs in Families With Parkinson Disease
Dana B. Hancock, BS; Eden R. Martin, PhD; Jeffrey M. Stajich, PA-C; Rita Jewett, RN; Mark A. Stacy, MD; Burton L. Scott, PhD, MD; Jeffery M. Vance, PhD, MD; William K. Scott, PhD
Arch Neurol. 2007;64:576-580.
For what its worth they use a statistical method of evaluation that I'm not too familiar with (GEE - Population-averaged generalized estimating equations) so I'm really not qualified to comment on the accuracy of the P-values here, but the results are in the same direction as pretty much all other research with regard to smoking (as they note in the section I quoted NSAIDs were not found to be significant with goes against some previous articles).
As a general rule, sample selection is done in such a way as to exclude those people who are dying from other diseases prior to onset, especially in this sort of age related (sporadic PD tends to be later onset, the earlier onset PD tends to be a matter of mendelian type mutations) disease there's exclusion criteria in sample selection (no co-morbidities or other diseases that would mask or otherwise interfere with the disease of interest).
Bottom line (for me) - it fits with previous studies, its a genetic test that should be done, but all in all its not surprising or all that novel. But just like the studies that show drinking lots of red wine is good for resviritrol (anti-oxidant polyphenol) drinking the amount of red wine that would give you a noticable effect will increase your risk for other diseeases.