Increased Risk of Dementia with Androgen Deprivation Therapy Possible

Chicago—There may be an increased risk of dementia in men with prostate cancer who are treated with androgen deprivation therapy (ADT); however, data from previous studies have shown conflicting results. Kevin Thomas Nead, MD, and colleagues recently conducted a systematic review and meta-analysis to determine the association of prostate cancer treatment with ADT and the risk of dementia.

The researchers reported results of the review and meta-analysis during a poster session at the 2017 ASCO Annual Meeting. The poster was titled Androgen Deprivation Therapy in the Treatment of Prostate Cancer and Dementia Risk: A Systematic Review and Meta-Analysis.

Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement guidelines, the researchers conducted a systematic review of articles that reported the outcome of dementia among men with prostate cancer in patients exposed to ADT compared with a lesser-exposed comparison group (men not treated with ADT or those treated intermittently with ADT).

On December 4, 2016, two authors independently conducted searches in PubMed (1966-present), Web of Science (1945-present), Embase (1966-present), and PsycINFO (1806-present). The researchers utilized the Newcastle-Ottawa Scale criteria to assess the validity of each study. Studies that reported an effect estimate and controlled for confounding were included in the meta-analyses. In the presence or absence of heterogeneity, random- or fixed effects meta-analytic models were used, respectively, per the I2 statistic. Egger and Begg’s tests were used to evaluate small study effects.

Nine studies were included in the systematic review; of those, seven studies reported an adjusted effect estimate for risk of dementia. A random-effects meta-analysis of studies that reported any dementia outcome, representing 50,541 individuals, demonstrated an increased risk of dementia among men treated with ADT (hazard ratio [HR], 1.47; 95% confidence interval [CI], 1.08-2.00; P=.02).

The researchers conducted separate meta-analyses of studies that reported all-cause dementia (HR, 1.46; 95% CI, 1.05-2.02; P<.001) and Alzheimer’s disease (HR, 1.25; 95% CI, 0.99-1.57; P=.06). The I2 statistic to evaluate the proportion of heterogeneity variation was 76% (95% CI, 47%-89%; P<.001). There was no evidence of bias from small study effects (Egger, P=.19; Begg, P=1).

In conclusion, the researchers said, “The currently available combined evidence suggests that ADT in the treatment of prostate cancer may be associated with an increased risk for dementia. The potential for neurocognitive deficits secondary to ADT should be discussed with patients and evaluated prospectively.”

Source: Nead KT, Sinha S, Lguyen P. Androgen deprivation therapy in the treatment of prostate cancer and dementia risk: a systematic review and meta-analysis. Abstract of a poster presented at the 2017 American Society of Clinical Oncology Annual Meeting, June 5, 2017, Chicago, Illinois.