Effect of One Month Exposure to Components of Reprometabolic Syndrome on Physical Activity & Body Composition in Lean Women

Background: Subfertility in obese women is associated with chronic pituitary suppression, reduced sensitivity to GnRH and decreased sex steroid production. We have found evidence for a combined effect of hyperinsulinemia and high circulating fatty acids to acutely (4h infusion) suppress pituitary gonadotropin secretion and are currently investigating the effects of one-month exposure to a eucaloric high-fat diet (HFD) on gonadotropin levels in lean women. The aim of this study is to examine the effect of the one-month HFD on physical activity and body composition.

Methods: 12 normal weight (BMI < 25 kg/m2), normally cycling female participants of reproductive age were given a one-month eucaloric HFD, from the onset of menses in one cycle through the next, with 48% calories from fat. A Fitbit was provided to monitor changes in daily activity and sleep throughout the study. Measurement of gonadotropin pulsatility and reproductive hormones were done using frequent blood sampling and daily urine excretion, respectively. These measurements were obtained for a total of 4 menstrual cycles: 1 pre-diet cycle, the HFD cycle, and 2 post-diet cycles. DEXA body composition was measured at baseline and at the end of the 2nd post diet cycle. Pre and post diet comparisons were done using linear mixed model testing and reported as estimated means ± standard error.

Results: Mean number of daily steps were (9,226 ± 1,140) pre diet, (9,132 ± 1,140) during the diet and (7,533 ± 1,140) post diet. Daily active calories were (1,982 ± 99) pre diet, (1,975 ± 99) during the diet and (1,856 ± 99) post diet. Means in the HFD cycle did not differ from the pre-diet cycle. Daily sleeping minutes pre diet were (443 ± 19), (451 ± 20) during the diet and (412 ± 19) post diet, with no statistical difference between the 3 time points. BMI did not differ between pre-diet (21.84 ± 0.52) and post-diet (21.77 ± 0.52). DEXA body composition measurements indicated a statistically significant decrease in total fat percentage, (32.26 ± 1.53) pre diet and (31.31 ± 1.53) post diet, which does not appear clinically significant as the difference of less than 1% falls within the anticipated measurement error of the method. Visceral fat volume (cm3) did not differ between pre diet (299.51 ± 27.76) and post diet (295.53 ± 27.76).

Conclusions: The complete cohort has not yet been fully recruited and analyzed. These preliminary findings indicate that women consuming a one-month, HFD maintain their usual level of physical activity and sleep patterns, and do not appear to sustain change in visceral fat. Further accrual of participants should clarify the small decrease in total body fat observed without a change in BMI.

Supported by HD087314 ROI to NS UL1TR002535 to the Colorado Clinical and Translational Sciences Institute.

The Prostate, Lung, Colorectal and Ovarian Cancer (PLCO) Screening Trial Pathology Tissue Resource

BACKGROUND

Pathology tissue specimens with associated epidemiologic and clinical data are valuable for cancer research. The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial undertook a large-scale effort to create a public resource of pathology tissues from PLCO participants who developed a cancer during the trial.

METHODS

Formalin-fixed paraffin-embedded tissue blocks were obtained from pathology laboratories on a loan basis for central processing of tissue microarrays, with additional free-standing tissue cores collected for nucleic acid extraction.

RESULTS

Pathology tissue specimens were obtained for prostate cancer (n = 1,052), lung cancer (n = 434), colorectal cancer (n = 675) and adenoma (n = 658), ovarian cancer and borderline tumors (n = 212), breast cancer (n = 870), and bladder cancer (n = 204). The process of creating this resource was complex, involving multidisciplinary teams with expertise in pathology, epidemiology, information technology, project management, and specialized laboratories.

CONCLUSIONS

Creating the PLCO tissue resource required a multistep process, including obtaining medical records and contacting pathology departments where pathology materials were stored after obtaining necessary patient consent and authorization. The potential to link tissue biomarkers to prospectively collected epidemiologic information, screening and clinical data, and matched blood or buccal samples offers valuable opportunities to study etiologic heterogeneity, mechanisms of carcinogenesis, and biomarkers for early detection and prognosis.

IMPACT

The methods and protocols developed for this effort, and the detailed description of this resource provided here, will be useful for those seeking to use PLCO pathology tissue specimens for their research and may also inform future tissue collection efforts in other settings. Cancer Epidemiol Biomarkers Prev; 25(12); 1635-42. ©2016 AACR.

Participants' Views of Retention Materials Used in the PLCO Cancer Screening Trial

OBJECTIVE

To obtain information from participants in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial regarding their perception of the retention materials employed by the screening centers. Also, to determine the viability of using email or the internet as a data collection tool with an older population.

DESIGN

Three of ten PLCO screening centers queried participants towards the end of the study (2010) as to their opinions of the various retention materials and whether they would have been willing to use electronic communication for study activities, had the option been available.

SETTING

The questionnaires were administered by mail, and responses were returned to the originating screening center.

PARTICIPANTS

The participants in this study consisted of all the active participants at three PLCO screening centers: the University of Colorado Anschutz Medical Campus, the University of Utah, and Henry Ford Health System.

METHODS

A short, self-administered questionnaire was mailed to all active participants at three PLCO centers (n=41,482). This was a one-time mailing with no follow-up, as the responses were designed to be anonymous in order to obtain the most honest responses.

RESULTS

The response rate was 62%. Of respondents, 97% reported their PLCO experience was good or excellent. Nearly 50% of respondents indicated that receipt of an annual newsletter made them more likely to participate; newsletter features they reported as most important were those that conveyed information on cancer, study findings, and how their data were being used. Results did not support study coordinators' suppositions that receipt of a token gift or birthday card by participants was important for retention. Fewer than 30% of respondents indicated that they would have been unwilling to use a secure website to complete study forms.

CONCLUSION

These data indicate the importance of querying participants rather than relying on impressions of study staff, and also indicate that the internet will be a viable means of data collection in future prevention studies that include older Americans.

Non-compliance with the initial screening exam visit in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial

OBJECTIVE

Identify predictors of non-compliance with first round screening exams in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

METHOD

The PLCO was conducted from 1993 to 2011 at 10 US institutions. A total of 154,897 healthy men and women ages 55-74 years were randomized. Intervention arm participants were invited to receive gender-appropriate screening exams for prostate, lung, colorectal and ovarian cancer. Using intervention-arm data (73,036 participants), non-compliance percentages for 13 covariates were calculated, as were unadjusted and adjusted odds ratios (ORs), and 95% confidence intervals. Covariates included demographic factors as well as factors specific to PLCO (e.g., method of consent, distance from screening center).

RESULTS

The rate of non-compliance was 11% overall but varied by screening center. Significant associations were observed for most covariates but indicated modest increases or decreases in odds. An exception was the use of a two-step consent process (consented intervention arm participants for exams after randomization) relative to a one-step process (consented all participants prior to randomization) (OR: 2.2, 95% CI: 2.0-2.5). Non-compliance percentages increased with further distance from screening centers, but ORs were not significantly different from 1.

CONCLUSIONS

Many factors modestly influenced compliance. Consent process was the strongest predictor of compliance.