Online Appendix: Effect of Perineal Self-Acupressure on Constipation: a Randomized Controlled

Online Appendix: Effect of Perineal Self-Acupressure on Constipation: A Randomized Controlled Trial

Ryan Abbott MD, JD, MTOM12*

Ian Ayres PhD, JD3

Ed Hui MD1

Ka-Kit Hui MD1

1 Division of General Internal Medicine and Health Services Research, David Geffen School of Medicine at University of California, Los Angeles, Department of Medicine

2Southwestern Law School

3 Yale Law School

* Corresponding Author: Ryan Abbott, Department of Medicine, University of California, Los Angeles, 1033 Gayley Ave, Suite 111, Los Angeles, CA 90024. Telephone: (310) 794-0712. Fax: (310) 794-3310. Email: .

Online Appendix 1. Extended Literature Review

This supplementary material provides additional evidence from the literature on the specific mechanisms by which perineal pressure might aid in defecation.

Online Appendix 2. Patient Educational Materials

1. Perineal Self-Acupressure (Female Version)
2. Perineal Self-Acupressure (Male Version)
3. Patient Information: Constipation in Adults (The Basics) (© UpToDate)
4. Patient Information: Hemorrhoids (The Basics) (© UpToDate)

Online Appendix 3. Patient Surveys

1. PAC-QOL (© 2001 Johnson & Johnson.)
2. Modified Bowel Function Index
3. Hemorrhoid-specific questions (de novo)
4. SF-12v2 ( 1994, 2002 Medical Outcomes Trust and QualityMetric Incorporated.)
5. Treatment group only questionnaire (only asked after trial period, de novo)

Online Appendix 4. SupplementaryStatistical Analyses

A.LOCF (all individual questions).

B.Complete case analysis.

C.Multiple imputation analysis.

D.Seemingly unrelated regression analysis (with LOCF dataset).

E.Ordered probit analysis (with LOCF dataset).

F.Treatment group only questionnaire analysis.

G.Instrumental variables analysis (with LOCF dataset).

H.Demographics interaction analysis (with LOCF dataset).

I.Pre-treatment symptom interaction analysis (with LOCF dataset).

Online Appendix 5. Statistical Code

This supplementary material has been provided by the authors to give readers additional information about their work.

Online Appendix 1

Extended Literature Review

Several studies have examined the use perineal pressure or transvaginal pressure to aid in defecation [12, “Many females with obstructed defecation applydigital pressure on their perineum to facilitate defecation.”; 12, 92% of patients with obstructed defecation “statedthat they applied perineal pressure on a regular basis tofacilitate their defecation” (p. 370); 31, “patients in whom constipation is relievedwith digital vaginal pressure to facilitate defecation” (Chapter 18,pp. 8-18)]. Digitally applying transvaginal (or perineal) pressure has been used by patients with rectocele or descending perineum syndrome [31, “Women may report the need to use their thumb or fingersto support the posterior vaginal wall to complete defecation” (Chapter 18); 9; 12].

Perineal pressure has also been shown to substantially increase “rectal tone” (measured by decreased rectal balloon volume) [11, 12]. For example, the following figure taken from [12] shows the perineorectal reflex (which across 17 subjects produced a tonic response that averaged 52% greater than when subjects did not apply perineal pressure):

Source: Gosselink M, Schouten W(2002) [2002]

The literature suggests multiple mechanisms by which perineal or transvaginal pressure might aid defecation:

1) Break up scybalous stools, [13; 14, “In women, applying transvaginal pressure with the otherhand may also aid fragmentation and expulsion” (p. 661)];

2) Protect the tissue from overstretching and relax the anal sphincters to allow stool passage, [2];

3) Relax the puborectalis allowing the anorectal angle to straighten, allowing a less obstructed descent of the stool [15; 16; 12, “Preston and Lennard-Jones have suggested that the puborectalis muscle ispushed upward by this maneuver. This mightstraighten the anorectal angle, enhancing the alignmentbetween the rectum and anal canal” (p. 370)];

4) Stimulate extrinsic parasympatheticsacral nerves (and pons cerebri) to enhance rectal sensoryperception and rectal tone, [12];

5) Compensate for rectal wall abnormalities (such as rectocele or descending perineum syndrome) [8, 9].

Just as impacted stools are fragmented by internal digital manipulation, it is possible that similar digital pressure applied to the perineum might be sufficient to pulverize hardened stool. Physiologically, because the stool during attempted defecation descends into the rectum and can be lodged between the internal sphincter and the pelvic diaphragm, the stool may be sufficiently stable to prevent dorsal or anterior movement of the stool in response to the perineal or transvaginal pressure. Moreover, because the perineum descends by 1.0 to 3.5 cm. during defecation, the posterior portion of the stool becomes more susceptible to dorsal pressure. Fragmenting or pulverizing the posterior portion is particularly important with slow-transit constipation, because the posterior portion is likely to be the most scybalous portion of the stool [26-29]. If needed, digital perineal pressure to fragment the stool can be applied repeatedly as soften portions of the stool are expulsed from the body.

In addition to treating constipation, perineal massage may treat hemorrhoids, which are related to chronic constipation and are associated excessive straining [2]. Symptoms of hemorrhoids include itching, pain, bleeding, rectal prolapse and vein thromboses. One important way to prevent the development and progression of hemorrhoids is to effectively treat constipation [2, 17]. Stool softeners and laxatives have been shown to be effective in reducing risk of hemorrhoid recurrence [17, 30]. One of the standard treatments for impacted stools is to manually disimpact the stool [13, 14].

References

[26] Cowgill GR, Anderson WE, Sullivan AJ. The form of the stool as a criterion of laxation. JAMA. 1933 Jul 22;101(4):273–5.

[27] Burnett, FL. Fecal Units and Intestinal Rate: A Basis for theStudy of Health and Intestinal Indigestion. Boston Med Surg J. 1921 Apr 14;184:371–6.

[28] Burnett, FL.The Intestinal Rate and the Form of theFeces. Am J Roentgenol. 1923 Aug;10:599–604.

[29] Sonnenberg A, Koch TR. Physician visits in the United States for constipation: 1958 to 1986. Dig Dis Sci. 1989 Apr;34(4):606–11.

[30] Petticrew M, Rodgers M, Booth A. Effectiveness of laxatives inadults. Qual Health Care. 2001 Dec;10(4):268–73.

[31] Feldman M, Friedman LS, Brandt LJ, editors.9th ed. Vol. 1. Sleisenger and Fordtran’s Gastrointestinal and Liver Disease‬: Pathophysiology/Diagnosis/Management‬.Philadelphia: Saunders;c2010. 3184 p.‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬

eAppendix 2

Below are the 4handouts participants received. They are, in order:

A.Perineal Self-Acupressure (Female Version) (only given to female treatment group participants)

B.Perineal Self-Acupressure (Male Version)(only given to male treatment group participants)

C.Patient Information: Constipation in Adults (The Basics) (© UpToDate) (given to all participants)

D.Patient Information: Hemorrhoids (The Basics) (© UpToDate) (given to all participants)

Handout A (Female Version)

Handout B (Male Version)

Handout C

Handout D

Online Appendix 3

Below are the 5 surveys participants completed. They are, in order:

A.PAC-QOL (© 2001 Johnson & Johnson)

B.Modified Bowel Function Index

C.Hemorrhoid-specific questions (de novo)

D.SF-12v2 ( 1994, 2002 Medical Outcomes Trust and QualityMetric Incorporated)

E.Treatment group only questionnaire (only asked after trial period, de novo)

Survey A

Survey B

1. During the last 7 days, how would you rate your ease of defecation on a scale from 0 to 100, where 0 = easy or no difficulty and 100 = severe difficulty?”

1. During the last 7 days, how would you rate your feeling of incomplete bowel evacuation on a scale from 0 to 100, where 0 = no feeling of incomplete evacuation and 100 = a very strong feeling of incomplete evacuation?

1. During the last 7 days, how would you rate your constipation on a scale from 0 to 100, where 0 = not at all and 100 = very strong?

Survey C

Hemorrhoid-specific questions

In the last 4 weeks, have you experienced new episodes with hemorrhoids?

Yes ⎕No ⎕

Survey D

SF-12v2

Your Health and Well-Being

This survey asks for your views about your health. This information will help keep track of how you feel and how well you are able to do your usual activities. Thank you for completing this survey!

For each of the following questions, please mark an in the one box that best describes your answer.

1. In general, would you say your health is:

1. The following questions are about activities you might do during a typical day. Does your health now limit you in these activities? If so, how much?

1

1. During the past 4 weeks, how much of the time have you had any of the following problems with your work or other regular daily activities as a result of your physical health?
2. During the past 4 weeks, how much of the time have you had any of the following problems with your work or other regular daily activities as a result of any emotional problems (such as feeling depressed or anxious)?

1. During the past 4 weeks, how much did pain interfere with your normal work (including both work outside the home and housework)?

1. These questions are about how you feel and how things have been with you during the past 4 weeks. For each question, please give the one answer that comes closest to the way you have been feeling. How much of the time during the past 4 weeks…

1. During the past 4 weeks, how much of the time has your physical health or emotional problems interfered with your social activities (like visiting with friends, relatives, etc.)?

Survey E

TREATMENT GROUP ONLY

1. Were the instructions in the “perineal self-acupressure” pamphlet clear?

Yes ⎕No ⎕

1. Did you try using the “perineal self-acupressure” technique?

Yes ⎕No ⎕

If no, please indicate why:

______

1. For the 4 weeks, please estimate the frequency with which you used the technique:

1. If you used the technique, please answer the following questions.

1. Did you have difficulty using the technique?

Yes ⎕No ⎕

If yes, please indicate why:

______

1. Did the “perineal self-acupressure” technique help you defecate more easily?

Yes ⎕No ⎕

1. Did the “perineal self-acupressure” technique make defecating less painful?

Yes ⎕No ⎕

1. Did the “perineal self-acupressure” technique help you break up, soften, or pass your stools?

Yes ⎕No ⎕

1. Do you feel that the technique helped you to avoid having a hemorrhoid or lessened the impact of an existing hemorrhoid?

Yes ⎕No ⎕

If no, please indicate why: ______

1. Do you feel that the technique helped you to avoid or better manage the effects of constipation?

Yes ⎕No ⎕

If no, please indicate why: ______

1. Will you continue to perform “perineal self-acupressure”

Yes ⎕No ⎕

1. Will you recommend this method to family members/friends?

Yes ⎕No ⎕

1. If you didn’t use the technique, please tell us why:

______

1. Please provide any additional comments about your experience with the “perineal self-acupressure” pamphlet including suggestions on how we might make the instructions clearer.

______

______

Online Appendix 4

There are 9 sections to this appendix.

1. LOCF (all individual questions)
2. Complete case analysis
3. Multiple imputation analysis
4. Seemingly unrelated regression analysis (with LOCF dataset)
5. Ordered probit analysis (with LOCF dataset)
6. Treatment group only questionnaire analysis
7. Instrumental variables analysis (with LOCF dataset)
8. Demographics interaction analysis (with LOCF dataset)
9. Pre-treatment symptom interaction analysis (with LOCF dataset)

Section A: LOCF (all individual questions)

Table A shows the treatment effect for each individual question asked. These are difference-in-different regressions with individual fixed effects. These fixed effects effectually difference the pre- and post-treatment data. N=200.

Table A

Note: These are difference-in-difference regressions with individual fixed effects.

Section B: Complete case analysis

In this analysis, we kept only the respondents who were not lost to follow up (N=182). Table B below shows the treatment effects for that group only.

Table B

Note: These are difference-in-difference regressions with individual fixed effects.

Section C: Multiple imputation analysis

In this analysis, we use multiple imputation methodology to imputes the missing values from participants who were lost to follow-up. We utilized 100 imputed datasets to do so, using the commands under mi in Stata. Table C presents the treatment effect results.

Table C

Section D: Seemingly unrelated regressions

In this robustness analysis, we use seemingly unrelated regression specifications to account for correlated residuals in the models. The results (LOCF dataset) are presented in Table D. Note that the variable PAC all is not included, as it is collinear with the four PAC subscales.

Table D