Okiedo:
Hormonal predictors of prostate cancer: a meta-analysis.
PURPOSE: Although there is strong circumstantial evidence that androgens are implicated in the etiology of prostate cancer, epidemiologic investigations have failed to demonstrate consistently that one or more steroid hormones are implicated. In contrast, recent epidemiologic studies unequivocally link serum insulin-like growth factor 1 (IGF-1) levels with risk for prostate cancer. METHODS: We have performed the first meta-analysis of all previously published studies on hormonal predictors of risk for prostate cancer. RESULTS: A meta-analysis restricted to studies that performed mutual adjustment for all measured serum hormones, age, and body mass index indicated that men whose total testosteron is in the highest quartile are 2.34 times more likely to develop prostate cancer (95% confidence interval, 1.30 to 4.20). In contrast, levels of dihydrotestosterone and estradiol do not seem to play a role of equal importance. The only study that provides multivariably adjusted coïtus hormone-binding globulin data indicates that this binding protein is inversely related to prostate cancer risk (odds ratio, 0.46; 95% confidence interval, 0.24 to 0.89). Finally, all three studies that examined the role of serum IGF-1 have consistently demonstrated a positive and significant association with prostate cancer risk that is similar in magnitude to that of testosteron. CONCLUSION: Men with either serum testosteron or IGF-1 levels in upper quartile of the population distribution have an approximately two-fold higher risk for developing prostate cancer.
Adverse events associated with testosteron replacement in middle-aged and older men: a meta-analysis of randomized, placebo-controlled trials.
BACKGROUND: We performed a meta-analysis of randomized clinical trials to determine the risks of adverse events associated with testosteron replacement in older men. METHODS: The MEDLINE database was searched from 1966 to April 2004, using testosteron as the indexing term; limits included human, male, > or =45 years old, and randomized controlled trial. Of the 417 studies thus identified, 19 met the inclusion criteria: testosteron replacement for at least 90 days, men > or =45 years old with low or low-normal testosteron level, randomized controlled trial, and medically stable men. Odds ratios (ORs) were pooled using a random effects model, assuming heterogeneous results across studies, and were weighted for sample size. RESULTS: In the 19 studies that met eligibility criteria, 651 men were treated with testosteron and 433 with placebo. The combined rate of all prostate events was significantly greater in testosteron-treated men than in placebo-treated men (OR = 1.78, 95% confidence interval [CI], 1.07-2.95). Rates of prostate cancer, prostate-specific antigen (PSA) >4 ng/ml, and prostate biopsies were numerically higher in the testosteron group than in the placebo group, although differences between the groups were not individually statistically significant. testosteron-treated men were nearly four times as likely to have hematocrit >50% as placebo-treated men (OR = 3.69, 95% CI, 1.82-7.51). The frequency of cardiovascular events, sleep apnea or death was not significantly different between the two groups. CONCLUSIONS: Testosterone replacement in older men was associated with a significantly higher risk of detection of prostate events and of hematocrit >50% than was placebo; hematocrit increase was the most frequent adverse event associated with testosteron replacement. These data reaffirm the need to monitor hematocrit, PSA, and digital examination of the prostate during testosteron replacement in older men.
Ik weet niet of dat zo werkt. Heb ook niet om een onderbouwing gevraagd...
maar wil graag eens naar de cijfers kijken.
