Division of Epidemiology and Community Health, University of Minnesota, 1300 2nd Street South, Suite 300, Minneapolis, MN 55455, USA.
Cancer Causes Control. 2011 Jul;22(7):1003-10. doi: 10.1007/s10552-011-9773-0. Epub 2011 May 7.
Studies have reported higher cancer risk in individuals with psoriasis, a chronic inflammatory autoimmune disease; however, adjustment for potential confounders was lacking.
We examined the association of psoriasis with cancer incidence in 32,910 women after age 65 in the IWHS cohort linked to Medicare. Psoriasis was defined as: 2+ psoriasis claims from any Medicare file during 1991-2004 or 1+ psoriasis claim from a dermatologist (n = 719). Severe psoriasis was defined as 4+ psoriasis claims from a dermatologist in any year (n = 121). Cox proportional hazards regression, with psoriasis as a time-dependent variable was conducted to calculate hazard ratios (HR) and 95% confidence intervals (CI) of total (n = 6,488), breast (n = 2,066), lung (n = 742), and colon cancers (n = 947).
With age-adjustment, psoriasis (yes vs. no) was associated with increased risk of lung 1.9 (95% CI: 1.2-3.0), colon 1.6 (95% CI: 1.1-2.5), and total cancer 1.2 (95% CI, 1.0-1.4). After further adjustment for smoking, body mass index, education, physical activity, and hormone therapy use, only the association for colon cancer remained statistically significant (HR = 1.6, 95% CI: 1.0-2.4) and was stronger for severe psoriasis.
The observed association between psoriasis and colon cancer may reflect inflammatory or unidentified processes.
已有研究报告称，慢性炎症性自身免疫性疾病银屑病患者的癌症风险更高；然而，这些研究缺乏对潜在混杂因素的调整。
我们在 IWHS 队列中对 32910 名 65 岁以上的女性进行了研究，该队列与医疗保险相关联。银屑病的定义为：1991-2004 年期间任何一份医疗保险记录中有 2 次或以上的银屑病索赔，或有 1 次来自皮肤科医生的银屑病索赔（n=719）。严重银屑病的定义为在任何一年中，皮肤科医生有 4 次或以上的银屑病索赔（n=121）。使用 Cox 比例风险回归，将银屑病作为一个时间依赖性变量，计算总癌症（n=6488）、乳腺癌（n=2066）、肺癌（n=742）和结肠癌（n=947）的风险比（HR）和 95%置信区间（CI）。
在年龄调整后，银屑病（是 vs. 否）与肺癌的风险增加相关，HR 为 1.9（95% CI：1.2-3.0）、结肠癌为 1.6（95% CI：1.1-2.5）和总癌症为 1.2（95% CI：1.0-1.4）。在进一步调整吸烟、体重指数、教育程度、身体活动和激素治疗使用后，只有结肠癌的相关性仍具有统计学意义（HR=1.6，95% CI：1.0-2.4），且严重银屑病的相关性更强。
观察到的银屑病与结肠癌之间的关联可能反映了炎症或未识别的过程。
