Increased risk of cancer in chronic dialysis patients is confirmed in the Taiwanese population and it is necessary to develop different strategies for cancer screening in chronic dialysis patients among different ethnicities.

Mild hyperhomocysteinemia is an independent risk factor for cardiovascular disease and may result from a deficiency of folate, vitamin B-6 or vitamin B-12. Because vitamin B-12 deficiency is often associated with vegetarianism, this study was designed to examine the effect of Taiwanese vegetarian diets on B-vitamin status and plasma homocysteine levels. Female Buddhist lacto-vegetarians (n = 45; 31-45 y) and matched omnivores (n = 45) recruited in Hualien, Taiwan, were investigated. Taiwanese vegetarians consumed normal amount of folate, but only 21% of Taiwan Recommended Daily Nutrient Allowances (RDNA) values of vitamin B-12. Compared with the omnivores, the vegetarians had significantly higher levels of plasma folate (14.79 +/- 7.70 vs. 11.98 +/- 8.29 nmol/L), but lower levels of vitamin B-12 (207.7 +/- 127.1 vs. 403.5 +/- 138.9 pmol/L). Fasting plasma homocysteine levels were significantly higher in vegetarians than in omnivores (mean: 11.20 +/- 4.27 vs. 8.64 +/- 2.06 micromol/L; median: 10.5 vs. 8.5 micromol/L). Fasting plasma homocysteine was inversely correlated with plasma folate and vitamin B-12 in the vegetarian group. Multiple regression analysis revealed that plasma folate, vitamin B-12 and creatinine were independent determinants of homocysteine variation and contributed to 38.6% of homocysteine variation in the vegetarians. Compared with the omnivores, vegetarians also had significantly lower serum levels of valine, isoleucine, leucine, lysine, alanine and arginine, but higher levels of glycine. In the vegetarian group, fasting plasma homocysteine correlated negatively with serum threonine, lysine, histidine, arginine and cystine, and these amino acids contributed to 38.7% of homocysteine variation. In conclusion, the Buddhist nuns who consumed a lacto-vegetarian diet had mildly elevated fasting plasma homocysteine levels presumably due to lower levels of plasma vitamin B-12.

Objective: Both Alzheimer's disease (AD) and Parkinson's disease (PD) are associated with lower cancer risk. However, the cancer risk in Parkinson's disease dementia (PDD) has never been discussed. We aimed to test whether PDD is cancer protective, and to compare the types and risks of incident cancer between AD and PDD. Methods:We used Taiwan National Health Insurance Database. From 1997 to 2010, a total of 2,527 PD dementia and 25,557 AD patients were enrolled and followed up for cancer by record linkage. Age and sex standardized incidence ratios (SIRs) of overall and site-specific cancers were calculated. Cox proportional hazards model was used to compare the cancer risk of AD relative to PDD. Results:With an average 4.4 years of follow-up period, both AD and PDD were associated with lower overall cancer risk (SIR and 95% confidence interval (CI): 0.83 (0.77-0.89) and 0.70 (0.55-0.89), respectively). The adjusted overall cancer risk of AD was significantly higher than that of PDD (hazard ratio (HR) and 95% CI: 1.26 (1.04-2.53), p=0.02). As for the site-specific cancer risk, the colorectal cancer risk of AD was also significantly higher than that of PDD (SIR: 0.95 (0.80-1.12) and 0.53 (0.80-1.00); HR: 1.83 (1.07-3.14), p=0.029). Conclusions:Both AD and PDD are inversely associated with incident cancer. Compared to AD, PDD is associated with even lower cancer risk. The decreased cancer risk in PDD may be contributed by the combined effect from both AD and PD. The mechanism deserves further investigations.