Baseline subject characteristics predictive of compliance with study-mandated prostate biopsy in men at risk of prostate cancer: results from REDUCE

Characteristics Associated with the Use of Diagnostic Prostate Biopsy and Biopsy Outcomes in Australian Men

BACKGROUND

Population characteristics associated with the use of prostate biopsy are poorly understood. We described the use of diagnostic prostate biopsy and subsequent biopsy outcomes in a population-based Australian cohort.

METHODS

A total of 91,764 men from the Sax Institute's 45 and Up Study (New South Wales, Australia) recruited during 2006 to 2009 were included. Self-completed baseline questionnaires and linked administrative health data were used. Study period was from the date of recruitment to December 2013. Cox regression and logistic regression identified factors associated with receipt of biopsy and subsequent prostate cancer diagnosis.

RESULTS

During the study period, 5,089 participants had a diagnostic prostate biopsy, and 2,805 men (55.1% of those biopsied) received a cancer diagnosis. Men with a family history of prostate cancer (HR 1.55; 95% confidence interval (CI), 1.43-1.68), severe lower urinary tract symptoms (HR 1.62; 95% CI, 1.41-1.86), or a record of medication for benign prostatic hyperplasia (HR 1.34; 95% CI, 1.23-1.47) had increased risks of receiving a biopsy. Men with a family history of prostate cancer had increased odds of a positive biopsy (OR 1.21; 95% CI, 1.01-1.43). High alcohol consumption (≥21 drinks per week compared with 1-6 drinks per week) was associated with decreased risk of biopsy (HR 0.88; 95% CI, 0.80-0.96) but increased odds of a positive biopsy (OR 1.63; 95% CI, 1.32-2.02).

CONCLUSIONS

Certain characteristics are associated with both undertaking diagnostic prostate biopsy and positive biopsy outcomes.

IMPACT

This highlights the need to improve management of specific groups of men, especially those with clinical symptoms that overlap with prostate cancer, in their investigation for prostate cancer.

Sleep quality and prostate cancer aggressiveness: Results from the REDUCE trial

BACKGROUND

Disrupted sleep has been associated with increased risk of certain cancers. Little data exist in prostate cancer. We tested the association between sleep quality and prostate cancer diagnosis overall and by tumor grade in the Reduction by Dutasteride of Prostate Cancer Events chemoprevention trial. We hypothesized that worse sleep quality would be associated with increased tumor aggressiveness.

METHODS

At baseline, 5614 men completed a validated six-item questionnaire on sleep quality. We generated a composite score categorized into tertiles to measure overall sleep quality and assessed each sleep quality question individually. Logistic regression was used to test associations between baseline sleep quality and overall, low-grade and high-grade prostate cancer diagnosis at 2-year study-mandated biopsy. Models were stratified by nocturia.

RESULTS

Overall sleep quality was unrelated to overall or low-grade prostate cancer. Worse overall sleep quality was associated with elevated odds of high-grade prostate cancer (odds ratio [OR]_T3vsT1 1.15; 95% confidence interval [CI]: 0.83-1.60 and OR_T2vsT1 1.39; 95% CI: 1.01-1.92). Men reporting trouble falling asleep at night sometimes vs never had elevated odds of high-grade prostate cancer (OR: 1.51; 95% CI: 1.08-2.09) while trouble staying awake during the day was associated with decreased odds of low-grade prostate cancer (OR: 0.65; 95% CI: 0.49-0.86). Results were similar within strata of nocturia severity.

CONCLUSIONS

Overall, associations between sleep quality and prostate cancer were inconsistent. However, there was some evidence for a positive association between insomnia and high-grade prostate cancer, and an inverse relationship between daytime sleepiness and low-grade prostate cancer; findings that should be validated by future studies.

The impact of complications after initial prostate biopsy on repeat protocol biopsy acceptance rate. Results from the Prostate Cancer Research International: Active Surveillance JAPAN study

BACKGROUND

Patients with favorable-risk prostate cancer on active surveillance (AS) are strictly followed for safer execution. Repeat protocol biopsy is essential for evaluating cancer aggressiveness. However, the acceptance rate of repeat biopsy is not high enough because of the burdens of biopsy. We assessed the impact of complications after the initial biopsy on repeat protocol biopsy at 1 year using data from the Prostate Cancer Research International: Active Surveillance (PRIAS)-JAPAN study.

METHODS

We performed a retrospective analysis using a prospective cohort in the PRIAS-JAPAN study. Patients with favorable-risk prostate cancer (n = 856) who consented to participate in the PRIAS-JAPAN study from 2010 to 2018 were enrolled. Follow-up evaluations included regular prostate-specific antigen, digital rectal examination and biopsy. Rates of complications after biopsies and repeat protocol biopsy non-acceptance rate at 1 year were reported. Logistic regression analysis explored the association between the complications after the initial biopsy and repeat protocol biopsy non-acceptance.

RESULTS

Altogether, 759 patients (88.7%) actually proceeded to protocol at 1 year. Repeat protocol biopsy non-acceptance rate at 1 year was 14.9%. Regarding complications after the initial biopsy, hematuria (p = 0.028) and pain (p < 0.001) rates were significantly higher in the repeat biopsy non-acceptance group, but infection (p = 0.056) and hematospermia (p = 0.337) rates were not different. On multivariate logistic regression analysis, pain was a significant predictor for repeat protocol biopsy non-acceptance (odds ratio 4.68, 95% confidence interval 1.864-11.75; p = 0.001).

CONCLUSIONS

Pain at the initial biopsy negatively impacts patients' compliance with further protocol biopsies during AS.

Association Between Antidiabetic Medications and Prostate-Specific Antigen Levels and Biopsy Results

IMPORTANCE

Diabetic men appear to have a lower risk of prostate cancer. Whether antidiabetic medications are protective or potentially mask prostate cancer by lowering prostate-specific antigen (PSA) levels is unclear.

OBJECTIVE

To examine the associations of antidiabetic medication use with (1) PSA levels, (2) frequency of PSA testing, (3) receipt of biopsy following elevated PSA results, and (4) prostate cancer detection at biopsy.

DESIGN, SETTING, AND PARTICIPANTS

Population-based cohort study using data from the Stockholm PSA and Biopsy Register. Participants were all prostate cancer-free men aged 40 to 79 years residing in Stockholm County, Sweden, between January 1, 2006, and December 31, 2015. Data were analyzed from November 2018 to March 2019.

EXPOSURES

One or more prescription for metformin, sulfonylurea, or insulin, as recorded in Sweden's National Prescribed Drug Register.

MAIN OUTCOMES AND MEASURES

Levels of PSA following first exposure to antidiabetic medications were assessed using multivariable linear regression. Frequency of PSA testing was assessed via multivariable Poisson regression. Biopsy following elevated PSA (≥3.0 ng/mL) and prostate cancer detection at biopsy were assessed via multivariable logistic regression.

RESULTS

The cohort of 564 666 men (median [range] age, 65 [40-79] years) consisted of 4583 men initially exposed to metformin, 1104 exposed to sulfonylurea, and 978 exposed to insulin who were age matched with unexposed men (1:5). Exposed men had lower median (interquartile range) PSA levels before starting antidiabetic medications compared with unexposed men (1.2 [0.7-2.5] vs 1.6 [0.8-3.2] ng/mL). After accounting for baseline differences, PSA levels did not vary from those of unexposed men following exposure to antidiabetic medications. Frequency of PSA testing was higher for those receiving metformin (rate ratio, 1.07; 95% CI, 1.06-1.09) and sulfonylurea (rate ratio, 1.06; 95% CI, 1.03-1.08) but was lower for those receiving insulin (rate ratio, 0.79; 95% CI, 0.77- 0.81). Likelihood of biopsy after elevated PSA was lower among men receiving metformin (odds ratio, 0.87; 95% CI, 0.80-0.96) and insulin (odds ratio, 0.83; 95% CI, 0.74-0.93). There were no differences in prostate cancer detection at biopsy, regardless of PSA levels that triggered the biopsy.

CONCLUSIONS AND RELEVANCE

This study's findings do not support the hypothesis that the inverse association between diabetes and prostate cancer is mediated through antidiabetic medications lowering PSA levels to mask prostate cancer. They do suggest potential detection bias due to fewer biopsies among men receiving antidiabetic medications, which may explain the lower prostate cancer risk in men with diabetes.

The Association of Previous Prostate Biopsy Related Complications and the Type of Complication with Patient Compliance with Rebiopsy Scheme

PURPOSE

Prostate biopsy complications have important consequences that may affect patient compliance with rebiopsy schemes. However, to our knowledge this has not been studied in earnest. Thus, we evaluated whether previous prostate biopsy related complications and the type of complication were associated with repeat prostate biopsy compliance in a clinical trial with study mandated systematic biopsies.

MATERIALS AND METHODS

We retrospectively analyzed the records of 4,939 men 50 to 75 years old who underwent 2-year prostate biopsy and were recommended to undergo 4-year prostate rebiopsy in the REDUCE (Reduction by Dutasteride of Prostate Cancer Events) study. The analyzed biopsy complications were hematuria, urinary tract infection, acute urinary retention and hemospermia.

RESULTS

A total of 260 men (5.3%) had a 2-year prostate biopsy related complication, including hematuria in 180 (3.6%), urinary tract infection in 36 (0.7%), acute urinary retention in 26 (0.5%) and hemospermia in 102 (2.1%). A total of 474 men (9.6%) were noncompliant with 4-year rebiopsy. On univariable analysis any previous complication (OR 1.56, 95% CI 1.08-2.24, p = 0.018), urinary tract infection (OR 2.72, 95% CI 1.23-6.00, p = 0.013), acute urinary retention (OR 4.24, 95% CI 1.83-9.81, p = 0.016) and hemospermia (OR 1.78, 95% CI 1.03-3.06, p = 0.037) were associated with rebiopsy noncompliance. Hematuria was not associated with rebiopsy noncompliance (OR 1.19, 95% CI 0.74-1.91, p = 0.483). Results were unchanged on multivariable analysis, including for any complication (OR 1.65, 95% CI 1.08-2.26, p = 0.018), for urinary tract infection (OR 2.62, 95% CI 1.07-3.21, p = 0.029), for acute urinary retention (OR 4.51, 95% CI 1.93-10.54, p = 0.001), for hemospermia (OR 1.85, 95% CI 1.07-3.21, p = 0.029) and for hematuria (OR 1.19, 95% CI 0.74-1.93, p = 0.472).

CONCLUSIONS

In men who undergo repeat prostate biopsy a previous biopsy related complication and the type of complication were associated with lower compliance with rebiopsy schemes. Patients who experience biopsy related complications are ideal candidates to receive intervention regarding the importance of prostate rebiopsy to prevent noncompliance.

Serum cholesterol and risk of high-grade prostate cancer: results from the REDUCE study

Background

Epidemiologic evidence for a serum cholesterol-prostate cancer link is mixed. Prostate-specific antigen (PSA) is positively correlated with cholesterol, potentially increasing PSA-driven biopsy recommendations in men with high cholesterol, though biopsy compliance may be lower in men with comorbid conditions. These potential biases may affect PSA-driven biopsy rates and subsequent prostate cancer detection in men with high serum cholesterol. Our objective was to test the association between serum cholesterol and prostate cancer risk in men receiving PSA-independent, study-mandated prostate biopsies.

Methods

We conducted a post-hoc analysis of data from 4,974 non-statin users in REDUCE, a randomized trial in men with elevated PSA and a negative baseline biopsy. Men underwent 2- and 4-year trial-mandated prostate biopsies. Associations between baseline serum levels of total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and prostate cancer risk, overall and by Gleason grade (<7 vs. ≥7), were examined using multivariable logistic regression.

Results

High total serum cholesterol was associated with an increased risk of high-grade prostate cancer diagnosis (OR_per10mg/dl 1.05; 95% CI 1.00-1.09; p=0.048), but cholesterol was unrelated to either overall or low-grade prostate cancer risk (p-values>0.185). There was no association between serum LDL and overall, low- or high-grade prostate cancer risk (p-values>0.137). In contrast, elevated serum HDL was associated with increased risk of both overall (OR_per10mg/dl 1.08; 95% CI 1.01-1.16; p=0.033) and high-grade prostate cancer (OR_per10mg/dl 1.14; 95% CI 1.01-1.28; p=0.034).

Conclusions

In REDUCE, where all men received PSA-independent, trial-mandated biopsies thus ensuring complete prostate cancer ascertainment, high total serum cholesterol and high HDL were associated with increased risk of high-grade prostate cancer, supporting a cholesterol-prostate cancer link.

Are intensive data collection methods in pain research feasible in those with physical disability? A study in persons with chronic pain and spinal cord injury

PURPOSE

Intensive repeated measures data collection procedures, such as ecological momentary assessment (EMA) and end-of-day (EOD) diaries, are becoming more prominent in pain research. Existing data on the feasibility of such methods is encouraging; however, almost nothing is known about feasibility in clinical populations with significant physical disabilities. Research methodology feasibility is crucial to the inclusion of individuals with physical disability in pain research given the high prevalence and impact of pain in these populations. The aim of this study was to examine study compliance, protocol acceptability, and reactivity of intensive data collection methods in adults with chronic pain and spinal cord injury (SCI).

METHODS

Secondary analysis of data from a 7-day EMA and EOD diary study in a sample of 131 community dwelling adults with SCI.

RESULTS

Results showed rates of missing data ranged from 18.4 to 22.8% across measures. Participant compliance was related to time of day/presence of audible prompts, mobility aid use, race, and baseline levels of pain and pain interference, with more missing data at wake and bedtimes/no prompts, and for those who used hand-held mobility devices, identified as black/African American, and/or reported higher baseline pain and pain interference. Participants rated the study methodology as generally highly acceptable and expressed willingness to participate in similar studies of much longer duration. There was no evidence of reactivity, defined as temporal shifts in pain or pain interference ratings.

CONCLUSIONS

Overall, intensive pain data collection is feasible in persons with SCI with no evidence that the methodology impacts pain intensity or pain interference ratings.

Biases in Recommendations for and Acceptance of Prostate Biopsy Significantly Affect Assessment of Prostate Cancer Risk Factors: Results From Two Large Randomized Clinical Trials

Purpose To identify factors related to who undergoes a prostate biopsy in a screened population and to estimate the impact of biopsy verification on risk factor-prostate cancer associations. Patients and Methods Men who were screened regularly from the placebo arms of two large prostate cancer prevention trials (Prostate Cancer Prevention Trial [PCPT] and Selenium and Vitamin E Cancer Prevention Trial [SELECT]) were examined to define incident prostate cancer cohorts. Because PCPT had an end-of-study biopsy, prostate cancer cases were categorized by a preceding prostate-specific antigen/digital rectal examination prompt (yes/no) and noncases by biopsy-proven negative status (yes v no). We estimated the association of risk factors (age, ethnicity, family history, body mass index, medication use) with prostate cancer and quantified differences in risk associations across cohorts. Results Men 60 to 69 years of age, those with benign prostatic hyperplasia, and those with a family history of prostate cancer were more likely, and those with a higher body mass index (≥ 25), diabetes, or a smoking history were less likely, to undergo biopsy, adjusting for age and longitudinal prostate-specific antigen and digital rectal examination. Medication use, education, and marital status also influenced who underwent biopsy. Some risk factor estimates for prostate cancer varied substantially across cohorts. Black ( v other ethnicities) had odds ratios (ORs) that varied from 1.20 for SELECT (community screening standards, epidemiologic-like cohort) to 1.83 for PCPT (end-of-study biopsy supplemented with imputed end points). Statin use in SELECT provided an OR of 0.65 and statin use in in PCPT provided an OR of 0.99, a relative difference of 34%. Conclusion Among screened men enrolled in prostate cancer prevention trials, differences in risk factor estimates for prostate cancer likely underestimate the magnitude of bias found in other cohorts with varying screening and biopsy recommendations and acceptance. Risk factors for prostate cancer derived from epidemiologic studies not only may be erroneous but may lead to misdirected research efforts.

Racial differences in prostate inflammation: results from the REDUCE study

Prostate cancer (PC) risk differs between races, and we previously showed prostate inflammation in benign prostate tissue was linked with a lower future PC risk. However, whether prostate tissue inflammation varies by race is unknown. We analyzed baseline acute and chronic prostate inflammation by race in REDUCE, a 4-year, multicenter, placebo-controlled study where all men had a negative prostate biopsy prior to enrollment. We included 7,982 men with standardized central pathology review to determine the presence or absence of chronic or acute inflammation in baseline prostate biopsy tissue. Logistic regression was used to compare prostate inflammation by race, adjusting for confounders. Of 7,982 men, 7,271 were white (91.1%), 180 (2.3%) black, 131 (1.6%) Asian, 319 (4.0%) Hispanic and 81 (1%) unknown. A total of 78% had chronic and 15% had acute inflammation. On multivariable analysis relative to white men, black men were less likely (OR = 0.65, 95%CI: 0.41-1.03, p = 0.07) and Asian men more likely to have acute inflammation (OR = 1.74, 95%CI: 1.14-2.65, p = 0.001). Hispanic men had similar levels of acute inflammation as white men. Chronic inflammation did not significantly differ across races. We identified racial differences in acute inflammation, particularly in Asian men, in benign prostate tissue that inversely mirrored population-level data on PC race disparity. As we showed in REDUCE that acute inflammation is linked with lower future PC risk, if validated in future studies, these data suggest racial differences in prostatic acute inflammation may contribute in part to race differences in PC risk, especially among Asian men.