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Objectives. To evaluate the use of prostate-specific antigen (PSA) velocity (PSAV) in assessing prostate cancer risk among men with PSA levels less than 4.0 ng/mL.Methods. The relative risk of, and cumulative probability of freedom from, prostate cancer by PSAV was evaluated in 89 male participants (21 with cancer and 68 controls) of a longitudinal aging study—the Baltimore Longitudinal Study of Aging (National Institute on Aging)—who had serial PSA levels between 2.0 and 4.0 ng/mL for at least 18 months. The relative risk was estimated from a Cox proportional hazards regression model, and the disease-free probability was determined by Kaplan-Meier survival analysis. The sensitivity and specificity of PSAV were calculated as a measure of test validity.Results. The sensitivity and specificity of a PSAV of 0.1 ng/mL per year was 81% and 50%, respectively. The relative risk of prostate cancer was 6.53 (range 1.90 to 22.51) when the PSAV was 0.1 ng/mL per year or more compared with a PSAV of less than 0.1 ng/mL per year (P = 0.0029). At 10 years, the cumulative probability of freedom from prostate cancer was 97.1% (range 91.4% to 100%) and 35.2% (range 14.0% to 56.4%) when the PSAV was less than and greater than 0.1 ng/mL per year, respectively. Survival curves began to differ at less than 5 years after the baseline PSAV determination.Conclusions. The association between PSAV and the subsequent risk of prostate cancer suggests that the PSAV may be useful in the risk assessment of men with lower PSA levels. [Copyright &y& Elsevier]

: ObjectivesTo examine the relationship of insulin, glucose, and anthropometry with the subsequent risk of prostate cancer.: MethodsThe relative risk of prostate cancer by insulin, glucose, and anthropometric measures was evaluated in 823 male participants (87 patients with prostate cancer in 10,737 person-years of follow-up) of the Baltimore Longitudinal Study of Aging who had at least one fasting plasma insulin measurement, which was prediagnostic for those with prostate cancer. Age-adjusted and multivariate-adjusted relative risks were estimated from Cox proportional hazards regression models.: ResultsInsulin concentrations were in the normal range (defined as less than 20 μU/mL) for 95.1% of participants. Fasting insulin and glucose levels were unrelated to prostate cancer risk in our overall analysis (P for trend = 0.56 and 0.45, respectively). The relative risk of prostate cancer for the second through fourth quartiles of the waist/hip ratio compared with the lowest quartile was 2.10, 1.96, and 2.06, respectively (P for trend = 0.32). Risk was unrelated to waist circumference and body mass index.: ConclusionsThe results of this study do not conclusively support positive associations of markers of insulin and glucose metabolism and obesity with prostate cancer. Additional larger prospective studies with repeated measure of these parameters are warranted to explore these associations further. [Copyright &y& Elsevier]

Objectives: To examine the association of total energy intake and macronutrient contributors to energy with prostate cancer risk among men in the Baltimore Longitudinal Study of Aging., Methods: In the Baltimore Longitudinal Study of Aging cohort, 444 men completed at least one food frequency questionnaire (FFQ). At their earliest FFQ completion, men were 45 to 92 years old. The total number of prostate cancer cases (n = 68) consisted of men who were diagnosed with cancer before their FFQ completion (n = 46) and those who were diagnosed after their FFQ completion (n = 22). Multiple logistic regression analysis was used to calculate the odds ratio of prostate cancer and its 95% confidence interval., Results: Total energy intake was positively associated with prostate cancer. Compared with the lowest quintile of energy intake, the odds ratio for the highest quintile was 3.79 (95% confidence interval 1.52 to 9.48, P TREND = 0.002). Energy-adjusted intakes of protein, fat, and carbohydrates were not statistically significantly associated with prostate cancer risk., Conclusions: This analysis, in which we used current energy intake as a surrogate for past prediagnostic intake, suggests a higher risk of prostate cancer with increased energy intake.

Objective: To investigate the association between prostate cancer and calcium and other nutrients thought to influence the synthesis of 1,25-dihydroxyvitamin D [1,25(OH)2D]., Methods: We included in the analysis 454 male participants in the Baltimore Longitudinal Study of Aging who were 46 to 92 years old at the time of completion of a food frequency questionnaire. Among them, 69 men were diagnosed with prostate cancer during their lifetime. In 68% of the cases, the food frequency questionnaire was completed after the diagnosis of cancer. Multiple logistic regression analysis was used to calculate the odds ratio and 95% confidence interval of prostate cancer., Results: The median calcium intake was 788 mg/day. The adjusted odds ratio of prostate cancer for the highest tertile compared with the lowest tertile of calcium intake was 0.92 (95% confidence interval 0.48 to 1.77; P(trend) = 0.89). Likewise, no significant trends were found for phosphorus, vitamin D, fructose, or animal protein intake. Dairy products, including milk, were not associated with an increased risk of prostate cancer. The adjusted odds ratio of prostate cancer was 1.26 (95% confidence interval 0.57 to 2.79; P(trend) = 0.73) for men with high dairy intakes compared with those with low dairy intakes., Conclusions: The results of this study suggest that calcium intake within moderate limits is not associated with a notably increased risk of prostate cancer.