Anna But

Assessing the effect of treatment duration on the association between anti-diabetic medication and cancer risk.

Most studies that have evaluated the association between anti-diabetic medication and cancer risk have suffered from methodological drawbacks. To avoid time-related biases, we evaluated the effect of treatment duration on the cancer risk among naive users of anti-diabetic medication as compared to non-users. In addition, we addressed the influence of common risk factors such as smoking and BMI. The study population comprised 23,394 participants of FINRISK surveys. Data on cancer and anti-diabetic medication were linked with the study cohorts. We applied Lexis tabulation to the data and analyzed split records by using Poisson regression. Changes in cancer incidence in relation to treatment duration were examined by modeling the rate ratio (RR). After a median follow-up of 9 years, 53 cancer cases among users of anti-diabetic medication and 1,028 among non-users were diagnosed. No significant difference in cancer risk between users and non-users was observed after adjustment. The RR for all medication regardless of its duration was 1.01 [95% CI 0.75–1.33], and 1.37 [0.94–1.94] for period of 1–4 years. The results were similar for metformin, sulfonylurea, and insulin. This study demonstrates that evaluation of the variation in cancer risk in relation to treatment duration is of particular importance for enhancing the accuracy of conclusions on the link between exposure to anti-diabetic medication and cancer risk.

Periodontitis and cancer mortality: Register-based cohort study of 68,273 adults in 10-year follow-up: Periodontitis increases the fatal course of cancer

Periodontitis, a multifactorial infection‐induced low‐grade chronic inflammation, can influence the process of carcinogenesis. We studied with 10 years follow‐up of 68,273 adults‐based cohort the involvement of periodontitis as a risk factor for cancer mortality. Periodontal status was defined based on procedure codes of periodontal treatment. Rate ratios and absolute differences of overall and cancer mortality rates were assessed with respect to periodontal status using multiplicative and additive Poisson regression models, respectively. We adjusted for effect of age, sex, calendar time, socio‐economic status, oral health, dental treatments and diabetes. Data about smoking or alcohol consumption were not available. Altogether 797 cancer deaths occurred during 664,020 person‐years accumulated over a mean 10.1‐year follow‐up. Crude cancer mortality rate per 10,000 person‐years for participants without and with periodontitis was 11.36 (95% CI 10.47–12.31) and 14.45 (95% CI 12.51–16.61), respectively. Crude rate ratios for periodontitis indicated an increased risk of overall (RR 1.27, 95% CI 1.08–1.39) and pancreatic cancer (RR 1.69, 95% CI 1.04–2.76) mortality. After adjustment, the results showed even stronger associations of periodontitis with increased overall (RR 1.33, 95% CI 1.10–1.58) and pancreatic cancer (RR 2.32, 95% CI 1.31–3.98) mortality. A higher pancreatic cancer mortality among individuals with periodontitis contributed considerably to the difference in overall cancer mortality, but this difference was not due to pancreatic cancer deaths alone.

Trends in the incidence rate, type and treatment of surgically verified endometriosis – a nationwide cohort study

To study the trends in incidence rate, type and surgical treatment, and patient characteristics of surgically verified endometriosis during 1987–2012.

A Nationwide Cohort Study on the risk of non-gynecological cancers in women with surgically verified endometriosis: Endometriosis and Cancer

We assessed the association of surgically verified endometriosis and risk of non‐gynecological cancers according to the type of endometriosis (i.e., ovarian, peritoneal and deep infiltrating endometriosis). All diagnoses of endometriosis combined with relevant procedural codes were identified from the Finnish Hospital Discharge Register 1987–2012. Non‐gynecological cancers diagnosed after the endometriosis diagnosis were obtained from the Finnish Cancer Registry. The cohort of 49,933 women with surgically verified endometriosis and the sub‐cohorts of ovarian (n = 23,210), peritoneal (n = 20,187), and deep infiltrating (n = 2,372) endometriosis were analyzed separately. The endometriosis cohort contributed 838,685 person‐years of follow‐up and the Finnish female population served as the reference cohort. The standardized incidence ratio (SIR) and 95% confidence interval (95%CI) was calculated for each cancer separately. The follow‐up ended at emigration, death or on the 31st of December 2014. The non‐gynecological cancer risk was not increased among women with endometriosis (SIR 1.03, 95%CI 0.98–1.08). Endometriosis was associated with an increased risk of thyroid cancer in the entire cohort (SIR 1.43, 95%CI 1.23–1.64) and in the sub‐cohorts of ovarian and peritoneal endometriosis. We found a decreased risk of mouth and pharynx cancer (SIR 0.60, 95%CI 0.41–0.80), and of pancreatic cancer (SIR 0.76, 95%CI 0.58–0.96). The incidence of basal cell carcinoma was elevated in the entire cohort (SIR 1.18, 95%CI 1.10–1.25) and in the sub‐cohorts of ovarian and peritoneal endometriosis. In conclusion, women with surgically verified endometriosis have an altered risk of only few non‐gynecological cancers.