Baseline Features and Reasons for Nonparticipation in the Colonoscopy Versus Fecal Immunochemical Test in Reducing Mortality From Colorectal Cancer (CONFIRM) Study, a Colorectal Cancer Screening Trial

Importance

The Colonoscopy Versus Fecal Immunochemical Test in Reducing Mortality From Colorectal Cancer (CONFIRM) randomized clinical trial sought to recruit 50 000 adults into a study comparing colorectal cancer (CRC) mortality outcomes after randomization to either an annual fecal immunochemical test (FIT) or colonoscopy.

Objective

To (1) describe study participant characteristics and (2) examine who declined participation because of a preference for colonoscopy or stool testing (ie, fecal occult blood test [FOBT]/FIT) and assess that preference's association with geographic and temporal factors.

Design, Setting, and Participants

This cross-sectional study within CONFIRM, which completed enrollment through 46 Department of Veterans Affairs medical centers between May 22, 2012, and December 1, 2017, with follow-up planned through 2028, comprised veterans aged 50 to 75 years with an average CRC risk and due for screening. Data were analyzed between March 7 and December 5, 2022.

Exposure

Case report forms were used to capture enrolled participant data and reasons for declining participation among otherwise eligible individuals.

Main Outcomes and Measures

Descriptive statistics were used to characterize the cohort overall and by intervention. Among individuals declining participation, logistic regression was used to compare preference for FOBT/FIT or colonoscopy by recruitment region and year.

Results

A total of 50 126 participants were recruited (mean [SD] age, 59.1 [6.9] years; 46 618 [93.0%] male and 3508 [7.0%] female). The cohort was racially and ethnically diverse, with 748 (1.5%) identifying as Asian, 12 021 (24.0%) as Black, 415 (0.8%) as Native American or Alaska Native, 34 629 (69.1%) as White, and 1877 (3.7%) as other race, including multiracial; and 5734 (11.4%) as having Hispanic ethnicity. Of the 11 109 eligible individuals who declined participation (18.0%), 4824 (43.4%) declined due to a stated preference for a specific screening test, with FOBT/FIT being the most preferred method (2820 [58.5%]) vs colonoscopy (1958 [40.6%]; P < .001) or other screening tests (46 [1.0%] P < .001). Preference for FOBT/FIT was strongest in the West (963 of 1472 [65.4%]) and modest elsewhere, ranging from 199 of 371 (53.6%) in the Northeast to 884 of 1543 (57.3%) in the Midwest (P = .001). Adjusting for region, the preference for FOBT/FIT increased by 19% per recruitment year (odds ratio, 1.19; 95% CI, 1.14-1.25).

Conclusions and Relevance

In this cross-sectional analysis of veterans choosing nonenrollment in the CONFIRM study, those who declined participation more often preferred FOBT or FIT over colonoscopy. This preference increased over time and was strongest in the western US and may provide insight into trends in CRC screening preferences.

Randomized Trial of Medical versus Surgical Treatment for Refractory Heartburn

BACKGROUND

Heartburn that persists despite proton-pump inhibitor (PPI) treatment is a frequent clinical problem with multiple potential causes. Treatments for PPI-refractory heartburn are of unproven efficacy and focus on controlling gastroesophageal reflux with reflux-reducing medication (e.g., baclofen) or antireflux surgery or on dampening visceral hypersensitivity with neuromodulators (e.g., desipramine).

METHODS

Patients who were referred to Veterans Affairs (VA) gastroenterology clinics for PPI-refractory heartburn received 20 mg of omeprazole twice daily for 2 weeks, and those with persistent heartburn underwent endoscopy, esophageal biopsy, esophageal manometry, and multichannel intraluminal impedance-pH monitoring. If patients were found to have reflux-related heartburn, we randomly assigned them to receive surgical treatment (laparoscopic Nissen fundoplication), active medical treatment (omeprazole plus baclofen, with desipramine added depending on symptoms), or control medical treatment (omeprazole plus placebo). The primary outcome was treatment success, defined as a decrease of 50% or more in the Gastroesophageal Reflux Disease (GERD)-Health Related Quality of Life score (range, 0 to 50, with higher scores indicating worse symptoms) at 1 year.

RESULTS

A total of 366 patients (mean age, 48.5 years; 280 men) were enrolled. Prerandomization procedures excluded 288 patients: 42 had relief of their heartburn during the 2-week omeprazole trial, 70 did not complete trial procedures, 54 were excluded for other reasons, 23 had non-GERD esophageal disorders, and 99 had functional heartburn (not due to GERD or other histopathologic, motility, or structural abnormality). The remaining 78 patients underwent randomization. The incidence of treatment success with surgery (18 of 27 patients, 67%) was significantly superior to that with active medical treatment (7 of 25 patients, 28%; P = 0.007) or control medical treatment (3 of 26 patients, 12%; P<0.001). The difference in the incidence of treatment success between the active medical group and the control medical group was 16 percentage points (95% confidence interval, -5 to 38; P = 0.17).

CONCLUSIONS

Among patients referred to VA gastroenterology clinics for PPI-refractory heartburn, systematic workup revealed truly PPI-refractory and reflux-related heartburn in a minority of patients. For that highly selected subgroup, surgery was superior to medical treatment. (Funded by the Department of Veterans Affairs Cooperative Studies Program; ClinicalTrials.gov number, NCT01265550.).

Ovulation prediction and detection with the CUE Ovulation Predictor

Predicting ovulation is useful for managing the infertile patient and when done sufficiently in advance for fertility regulation by periodic abstinence. It has been reported that ovulation could be predicted by measurement of salivary and vaginal electrical resistance (SR and VR). These data from 32 menstrual cycles of 23 women were obtained to evaluate this technique. Data of 14 cycles were from subjects receiving clomiphene citrate (CC), while the others were from spontaneously ovulating subjects. A peak in SR was seen 5-7 days before the day of the LH peak in both natural and CC cycles. A correlation coefficient (r) of 0.94 was seen for the day of the SR peak and that of the LH peak. The SR trend was similar in both natural and CC cycles. VR in spontaneous cycles declined to a periovulatory nadir and then increased. The patterns of VR in CC cycles were similar except that values were initially depressed during and shortly after the end of CC therapy. Over 90% of VR increases were on the day of the LH peak and the day following. Results indicate that the method is useful for predicting ovulation in natural and CC cycles. Since the number of days by which ovulation is predicted exceeds the expected lifespan of spermatozoa in the female reproductive tract, the method also shows potential for use in natural family planning.

Physiological mechanisms associated with ovulation prediction using the CUE Ovulation Predictor

It has been shown that monitoring of salivary electrical resistance (SR) enables prediction of ovulation several days in advance, since a peak in SR is seen 5-6 days before the LH peak. This paper explores physiological mechanisms that may account for this change. The pathway whereby oestrogen stimulates aldosterone (ALDO) secretion acting through the renin-angiotensin system was considered. It is shown that this mechanism would only result in increasing SR as oestrogen values rise during the follicular phase and therefore is not an explanation of the SR peak and declining SR 5-6 days before the LH peak. The reported trend of sodium in milk of ovulating women parallels that of SR. It is shown that these changes are most likely to be due to a similar change in aldosterone levels. A possible role for adrenocorticotrophic hormone (ACTH) in causing the changes in aldosterone is discussed and supported with data from other independent studies as well as with preliminary data obtained from two normally ovulating subjects. Peaks in ACTH, ALDO and SR were coincidental and occurred 6 days before the LH peak. The temporal relationship observed among these variables suggest that ACTH, by affecting ALDO, modifies salivary electrolytes and hence SR.

Prediction of ovulation with the use of oral and vaginal electrical measurements during treatment with clomiphene citrate

This study was undertaken to evaluate the usefulness of measuring salivary and vaginal electrical resistance in monitoring ovulation induced by clomiphene citrate (CC). Data from 28 cycles of 12 women treated with CC were compared with those of 18 cycles of 13 women who were ovulating spontaneously. Patterns of salivary readings in CC and spontaneous cycles were similar and showed a preovulatory peak 6.2 (mean) days before the luteinizing hormone peak. The trend in vaginal readings for CC cycles differed from that of spontaneous ovulations in that the values were depressed during and shortly after CC therapy. Occurrence of the periovulatory nadir and subsequent rise was common to both groups. The rise in vaginal readings CC cycles occurred within 24 hours of the luteinizing hormone peak in 88% of cases. Retrospective analysis showed that, based on this method, artificial insemination would have been timed appropriately in 25 of 27 cycles or in every cycle, depending on the protocol used. The results indicate that the method is equally useful for predicting and confirming ovulation in cycles in which CC was used to induce ovulation as it is in spontaneous cycles.

A new method for predicting and confirming ovulation

Evaluation of a method for predicting and confirming ovulation by measurement of vaginal and salivary electrical resistance (VER and SER) was the purpose of this study. Eighteen menstrual cycles from 13 subjects were analyzed. A clearly defined nadir in VER at day 0, the day of the luteinizing hormone (LH) peak, followed by a pronounced increase the following day was observed. A peak in SER was consistently observed 5 to 6 days before day 0. The correlation coefficient (r) between the cycle day of the SER peak and cycle day of the LH peak was 0.94. After the peak in SER, values were low for several days but increased 1 to 2 days before the LH peak. Results indicate that monitoring of SER and VER may provide the basis for a simple method for predicting and confirming ovulation.

Comparison of electrical conductivity of milk with other indirect methods for detection of subclinical mastitis

Efficacy of detecting subclinical mastitis by electrical conductivity of milk was compared with that of other indirect methods including chloride, sodium, potassium, lactose, bovine serum albumin, and somatic cell count of milk. Quarter samples of foremilk, strippings, and bucket milk were obtained from 75 cows at the afternoon milking over 8 wk. Infection of quarters was ascertained by bacteriological analysis. Electrical conductivity, chloride, and sodium content of milk were more accurate for predicting infection status of quarters than were other variables. Most variables were more accurate in predicting infection when measures were in strippings rather than in foremilk or bucket milk. For measures in strippings, misclassifications by electrical conductivity were 11.2 and 15.5% for false positives and false negatives. The accuracy of the electrical conductivity of milk for detection of subclinical mastitis compared favorably with all indirect methods. Accuracy of detection and adaptability to both manual and automatic cow-side mastitis detection systems indicate that the method has considerable potential as a screening test for subclinical mastitis.

Effects of milking interval on selected milk constituents from normal and infected quarters

Effects of milking interval on electrical conductivity, chloride, sodium, potassium, lactose, and somatic cell counts of milk were determined. Quarter samples of foremilk, primary milk, and strippings were obtained from 12 cows after 3, 6, 9, 12, and 15-h milking intervals. The preceding interval to all experimental intervals was standardized at 12 h. Infection status of quarters was ascertained by bacteriological analysis. Effect of milking interval was significant on all variables measured. Highest conductivity, chloride, sodium, and cell counts were at the 3-h interval but declined to their lowest at the 9-h interval. Conductivity, chloride, and sodium then steadily increased from 9 to 15 h. Lactose followed the opposite trend and was highest at the 9-h interval. Trend was similar in samples from both uninfected and infected quarters; however, changes were more pronounced in the latter. Change of conductivity from infection varied with type of sample and milking interval with strippings being the most sensitive. All samples were least sensitive to these changes at the 9-h interval. Conductivity measurements on strippings will be more sensitive for detecting mastitis than measurements from foremilk or primary milk, especially measured following short milking intervals.

Electrical conductivity of milk for detection of mastitis

The potential value of electrical conductivity of milk as a screening test for subclinical mastitis was evaluated. Conductivity of foremilk and of postmilking strippings from 368 quarters of 92 cows was measured. Infection status of quarters was determined by bacteriological analysis of strict foremilk samples. Infections were classified as by primary or secondary pathogens, depending on the importance of the isolated organism as a mastitis pathogen. Somatic cells were counted on foremilk samples. Milk conductivity increased with infection. Conductivity of postmilking strippings was higher than that of foremilk in samples from quarters infected by primary pathogens. By thresholds which correctly classified at least 90% of normal quarters, accuracy of identifying primary pathogen infections by absolute conductivity was 62.8 and 96.2% with foremilk and postmilking strippings. Differential conductivity and combination of absolute and differential methods also were evaluated with the latter being the most effective. Number of quarters with elevated conductivity of postmilking strippings tended to be higher when somatic cell count was greater than 500,000/ml in both normal and infected groups. Conductivity of milk seems to hold promise as an indicator of subclinical mastitis.

Effect of length of milking interval and fat content on milk conductivity and its use for detecting mastitis

Foremilk and strippings were obtained from 20 cows at the morning and evening milkings where the milking intervals were 14 h and 10 h. Infection status was determined by bacteriological analysis. Conductivity of foremilk and strippings was determined. Cows then were switched to 12 h milking interval, and conductance of foremilk and strippings from both milkings was determined. Conductance of foremilk samples increased after longer milking interval. Accuracy in detecting infections by primary pathogens via conductivity of foremilk was also greater following the long interval. Conductivity of foremilk from morning and evening milkings were, however, similar when the milking interval was even. Conductivity of strippings was affected less by milking interval. Conductance determination on quarter samples from 28 cows on both a whole and fat-free basis indicated an inhibitory effect of milk fat on conductivity. Conductivity of skimmed strippings samples was greater than that of skimmed foremilk samples, indicating higher electrolyte in strippings, and may explain why conductivity of strippings is not significantly lower than of foremilk in spite of the higher fat content in the former