Antidiabetic Medication and Prostate Cancer Risk
Antidiabetic Medication and Prostate Cancer Risk
Decreased risk of prostate cancer in diabetic men has been reported. The authors evaluated the association between antidiabetic medication use and prostate cancer at the population level. All incident prostate cancer cases in Finland during 1995-2002 were identified from the Finnish Cancer Registry. Matched controls were provided by the Population Register Center (24,723 case-control pairs). Information on medication use was obtained from a comprehensive prescription database. Multivariable-adjusted odds ratios were computed by using conditional logistic regression. The authors found that prostate cancer risk was decreased for antidiabetic medication users (odds ratio = 0.87, 95% confidence interval: 0.82, 0.92). The decrease was observed for most drug groups. The odds ratio decreased in a dose-dependent fashion by quantity of use. Duration of antidiabetic treatment was inversely associated with overall prostate cancer risk and risk of advanced cancer. Similar risk reduction for users of different antidiabetic drugs suggests that diabetes, instead of the medication itself, is behind the association. This finding is unlikely to be secondary because of differential uptake of the prostate-specific antigen test or different prostate-specific antigen levels between medication users and nonusers; prevalence of testing in Finland is low. Dose and time dependency of the relation probably indicates that duration of diabetes is negatively associated with risk.
Type 2 (adult-type) diabetes is a condition currently affecting a substantial proportion of the Western population. Its development is often linked with obesity and resulting insensitivity to endogenous insulin, leading to impaired glucose balance. Type 1 (juvenile) diabetes is characterized by complete absence of endogenous insulin production and is not associated with obesity.
Medical therapy for adult-type diabetes is often started with oral drugs that improve glucose tolerance or increase insulin production, later possibly combined with injectable insulin treatment. Therapy for juvenile diabetes involves insulin when treatment begins.
Recent studies have reported a decreased prostate cancer risk for diabetic men, although the evidence is controversial. An inverse association of prostate cancer with metabolic syndrome has also been described, of which adult-type diabetes is an integral part.
It is currently unclear whether use of antidiabetic medication affects the association between diabetes and prostate cancer. One study has reported that adjustment for antidiabetic medication did not affect the negative association between diabetes and prostate cancer; another study suggested that the risk reduction for diabetic men could be restricted to users of sulfonylureas and insulin only.
Biologic effects of oral antidiabetic drugs in prostate cancer cells are not well known, whereas the effect of insulin metabolism on prostate cancer growth has been studied more extensively. To our knowledge, only 1 study has reported growth reduction via cell cycle arrest in prostate cancer cells and xenografts after metformin treatment. However, all types of antidiabetic drugs affect insulin metabolism, providing a possible indirect mechanism for the effect on prostate cancer.
In the current study, we evaluated prostate cancer risk for users of antidiabetic medication in a population-based setting.
Decreased risk of prostate cancer in diabetic men has been reported. The authors evaluated the association between antidiabetic medication use and prostate cancer at the population level. All incident prostate cancer cases in Finland during 1995-2002 were identified from the Finnish Cancer Registry. Matched controls were provided by the Population Register Center (24,723 case-control pairs). Information on medication use was obtained from a comprehensive prescription database. Multivariable-adjusted odds ratios were computed by using conditional logistic regression. The authors found that prostate cancer risk was decreased for antidiabetic medication users (odds ratio = 0.87, 95% confidence interval: 0.82, 0.92). The decrease was observed for most drug groups. The odds ratio decreased in a dose-dependent fashion by quantity of use. Duration of antidiabetic treatment was inversely associated with overall prostate cancer risk and risk of advanced cancer. Similar risk reduction for users of different antidiabetic drugs suggests that diabetes, instead of the medication itself, is behind the association. This finding is unlikely to be secondary because of differential uptake of the prostate-specific antigen test or different prostate-specific antigen levels between medication users and nonusers; prevalence of testing in Finland is low. Dose and time dependency of the relation probably indicates that duration of diabetes is negatively associated with risk.
Type 2 (adult-type) diabetes is a condition currently affecting a substantial proportion of the Western population. Its development is often linked with obesity and resulting insensitivity to endogenous insulin, leading to impaired glucose balance. Type 1 (juvenile) diabetes is characterized by complete absence of endogenous insulin production and is not associated with obesity.
Medical therapy for adult-type diabetes is often started with oral drugs that improve glucose tolerance or increase insulin production, later possibly combined with injectable insulin treatment. Therapy for juvenile diabetes involves insulin when treatment begins.
Recent studies have reported a decreased prostate cancer risk for diabetic men, although the evidence is controversial. An inverse association of prostate cancer with metabolic syndrome has also been described, of which adult-type diabetes is an integral part.
It is currently unclear whether use of antidiabetic medication affects the association between diabetes and prostate cancer. One study has reported that adjustment for antidiabetic medication did not affect the negative association between diabetes and prostate cancer; another study suggested that the risk reduction for diabetic men could be restricted to users of sulfonylureas and insulin only.
Biologic effects of oral antidiabetic drugs in prostate cancer cells are not well known, whereas the effect of insulin metabolism on prostate cancer growth has been studied more extensively. To our knowledge, only 1 study has reported growth reduction via cell cycle arrest in prostate cancer cells and xenografts after metformin treatment. However, all types of antidiabetic drugs affect insulin metabolism, providing a possible indirect mechanism for the effect on prostate cancer.
In the current study, we evaluated prostate cancer risk for users of antidiabetic medication in a population-based setting.