Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-23T20:53:02.184Z Has data issue: false hasContentIssue false
  • English
  • Français

Gastrointestinal Symptoms in Parkinson Disease: Clinical Aspects and Management

Published online by Cambridge University Press:  02 December 2014

D. Salat-Foix ,
C. N. Andrews ,
J. Meddings  and
O. Suchowersky
D. Salat-Foix*
Affiliation:
Movement Disorders Program, Department of Clinical Neurosciences, University of Calgary, Calgary
C. N. Andrews
Affiliation:
Division of Gastroenterology, Department of Internal Medicine, University of Calgary, Calgary
J. Meddings
Affiliation:
Division of Gastroenterology, Department of Internal Medicine, University of Calgary, Calgary
O. Suchowersky
Affiliation:
Movement Disorders Program, Department of Clinical Neurosciences, University of Calgary, Calgary Department of Medicine (Neurology) and Medical Genetics, University of Alberta, Edmonton, Alberta, Canada
*
Movement Disorders Program. Department of Clinical Neurosciences, Area 3, UCMC, 3350 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Although it is now generally recognized that the clinical spectrum of Parkinson disease (PD) is broader than its defining motor aspects, its various non-motor symptoms are often not routinely assessed in the clinical setting. As most of these symptoms are amenable to treatment, improved recognition would lead to more comprehensive management of the disease, and ultimately improve the quality of life for PD patients. In an attempt to increase the general awareness of physicians caring for these patients, this article focuses on the clinical manifestations and treatment of the gastrointestinal symptoms most commonly experienced by PD patients, as well as on the gastrointestinal side effects of antiparkinsonian treatments.

Type
Review Article
Information
Canadian Journal of Neurological Sciences , Volume 38 , Issue 4 , July 2011 , pp. 557 - 564
Copyright
Copyright © The Canadian Journal of Neurological 2011

References

1.Bower, JH, Maraganore, DM, McDonnell, SK, Rocca, WA.Incidence and distribution of parkinsonism in Olmsted County, Minnesota, 1976-1990. Neurology. 1999 Apr 12;52(6):1214–20.Google Scholar
2.Benito-León, J, Bermejo-Pareja, F, Morales-González, JM, et al.on behalf of the Neurological Disorders in Central Spain (NEDICES) Study Group. Incidence of Parkinson disease and parkinsonism in three elderly populations of central Spain. Neurology. 2004 Mar 9;62(5):734–41.CrossRefGoogle Scholar
3.Linder, J, Stenlund, H, Forsgren, L.Incidence of PD and parkinsonism in northern Sweden: a population-based study. Mov Disord. 2010 Feb 15;25(3):341–8.CrossRefGoogle ScholarPubMed
4.Hughes, AJ, Daniel, SE, Kilford, L, Lees, AJ.Accuracy of clinical diagnosis of idiopathic Parkinson’s disease: a clinico-pathological study of 100 cases. J Neurol Neurosurg Psychiatry. 1992 Mar;55(3):181–4.Google Scholar
5.Muzerengi, S, Contrafatto, D, Chaudhuri, KR.Non-motor symptoms: identification and management. Parkinsonism Relat Disord. 2007;13 Suppl 3:S450–6.Google Scholar
6.Pfeiffer, RF.Gastrointestinal dysfunction in Parkinson’s disease. Lancet Neurol. 2003 Feb;2(2):107–16.CrossRefGoogle ScholarPubMed
7.Natale, G, Pasquali, L, Ruggieri, S, et al.Parkinson’s disease and the gut: a well known clinical association in need of an effective cure and explanation. Neurogastroenterol Motil. 2008 Jul;20(7):741–9.Google Scholar
8.Jost, WH.Gastrointestinal dysfunction in Parkinson’s Disease. J Neurol Sci. 2010 Feb 15;289(1-2):69–73.CrossRefGoogle ScholarPubMed
9.Stacy, M, Bowron, A, Guttman, M, et al.Identification of motor and nonmotor wearing-off in Parkinson’s disease: comparison of a patient questionnaire versus a clinician assessment. Mov Disord. 2005 Jun;20(6):726–33.CrossRefGoogle ScholarPubMed
10.Chaudhuri, KR, Prieto-Jurcynska, C, Naidu, Y, et al.The nondeclaration of nonmotor symptoms of Parkinson’s disease to health care professionals: an international study using the nonmotor symptoms questionnaire. Mov Disord. 2010 Apr 30;25(6):697–701.CrossRefGoogle Scholar
11.Kyle, G.The physical, social and emotional effects of bowel dysfunction in Parkinson’s disease. Nurs Times. 2010 Aug 24-30;106(33):20–2.Google ScholarPubMed
12.Cersosimo, MG, Benarroch, EE.Neural control of the gastrointestinal tract: implications for Parkinson disease. Mov Disord. 2008 Jun 15;23(8):1065–75.Google Scholar
13.Dickson, DW, Braak, H, Duda, JE, et al.Neuropathological assessment of PD: refining the diagnostic criteria. Lancet Neurol. 2009 Dec;8(12):1150–7.Google Scholar
14.Braak, H, Rüb, U, Gai, WP, Del Tredici, K.Idiopathic PD: possible routes by which vulnerable neuronal types may be subject to neuroinvasion by an unknown pathogen. J Neural Transm. 2003 May;110(5):517–36.Google Scholar
15.Braak, H, de Vos, RA, Bohl, J, Del Tredici, K.Gastric alpha-synuclein immunoreactive inclusions in Meissner’s and Auerbach’s plexuses in cases staged for PD-related brain pathology. Neurosci Lett. 2006 Mar 20;396(1):67–72.Google Scholar
16.Greene, JG, Noorian, AR, Srinivasan, S.Delayed gastric emptying and enteric nervous system dysfunction in the rotenone model of PD. Exp Neurol. 2009 Jul;218(1):154–61.CrossRefGoogle Scholar
17.Drolet, RE, Cannon, JR, Montero, L, Greenamyre, JT.Chronic rotenone exposure reproduces PD gastrointestinal neuropathology. Neurobiol Dis. 2009 Oct;36(1):96–102.CrossRefGoogle ScholarPubMed
18.Blandini, F, Balestra, B, Levandis, G, et al.Functional and neurochemical changes of the gastrointestinal tract in a rodent model of PD. Neurosci Lett. 2009 Dec 31;467(3):203–7.CrossRefGoogle Scholar
19.Kalf, JG, de Swart, BJ, Borm, GF, et al.Prevalence and definition of drooling in PD: a systematic review. J Neurol. 2009 Sep;256(9):1391–6. Epub 2009 Mar 14.Google Scholar
20.Kalf, JG, Smit, AM, Bloem, BR, et al.Impact of drooling in PD. J Neurol. 2007 Sep;254(9):1227–32.Google Scholar
21.van der Burg, JJ, Didden, R, Jongerius, PH, Rotteveel, JJ.A descriptive analysis of studies on behavioural treatment of drooling (1970-2005). Dev Med Child Neurol. 2007 May;49(5):390–4.Google Scholar
22.South, AR, Somers, SM, Jog, MS.Gum chewing improves swallow frequency and latency in Parkinson patients: A preliminary study. Neurology. 2010;74;1198–202.Google Scholar
23.Arbouw, ME, Movig, KL, Koopmann, M, et al.Glycopyrrolate for sialorrhea in Parkinson disease: a randomized, double-blind, crossover trial. Neurology. 2010 Apr 13;74(15):1203–7.Google Scholar
24.Hyson, HC, Johnson, AM, Jog, MS.Sublingual atropine for sialorrhea secondary to parkinsonism: a pilot study. Mov Disord. 2002 Nov;17(6):1318–20.Google Scholar
25.Thomsen, TR, Galpern, WR, Asante, A, et al.Ipratropium bromide spray as treatment for sialorrhea in Parkinson’s disease. Mov Disord. 2007 Nov 15;22(15):2268–73.Google Scholar
26.Praharaj, SK, Arora, M.Amitriptyline for clozapine-induced nocturnal enuresis and sialorrhoea. Br J Clin Pharmacol. 2007 Jan;63(1):128–9.Google Scholar
27.Kushnir, M.Eilam A. Heldman E. Modafinil reduces drooling in Parkinson’s disease. Mov Disord 2006;21 Suppl 13: S598–9.Google Scholar
28.Lipp, A, Trottenberg, T, Schink, T, et al.A randomized trial of botulinum toxin A for treatment of drooling. Neurology. 2003 Nov 11;61(9):1279–81.Google Scholar
29.Ondo, WG, Hunter, C, Moore, W.A double-blind placebo-controlled trial of botulinum toxin B for sialorrhea in Parkinson’s disease. Neurology. 2004 Jan 13;62(1):37–40.CrossRefGoogle ScholarPubMed
30.Postma, AG, Heesters, M, van Laar, T.Radiotherapy to the salivary glands as treatment of sialorrhea in patients with parkinsonism. Mov Disord. 2007 Dec;22(16):2430–5.Google Scholar
31.Meningaud, JP, Pitak-Amnop, P, Chikhani, L, et al.Drooling of saliva: a review of the etiology and management options. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;101:48–57.Google Scholar
32.Miller, N, Allcock, L, Hildreth, AJ, et al.Swallowing problems in Parkinson disease: frequency and clinical correlates. J Neurol Neurosurg Psychiatry. 2009 Sep;80(9):1047–9.Google Scholar
33.Plowman-Prine, EK, Sapienza, CM, Okun, MS, et al.The relationship between quality of life and swallowing in PD. Mov Disord. 2009 Jul 15;24(9):1352–8.Google Scholar
34.González-Fernández, J, Prieto-Albin, R, Velasco-Palacios, L, et al.Digestive disorders in Parkinson’s disease: dysphagia and sialorrhea. Rev Neurol. 2010 Feb 8;50 Suppl 2:S51–4.Google Scholar
35.Castell, JA, Johnston, BT, Colcher, A, et al.Manometric abnormalities of the oesophagus in patients with PD. Neurogastroenterol Motil. 2001 Aug;13(4):361–4.Google Scholar
36.Nagaya, M, Kachi, T, Yamada, T, Igata, A.Videofluorographic study of swallowing in PD. Dysphagia. 1998 Spring;13(2):95–100.Google Scholar
37.Ertekin, C, Tarlaci, S, Aydogdu, I, et al.Electrophysiological evaluation of pharyngeal phase of swallowing in patients with PD. Mov Disord. 2002 Sep;17(5):942–9.Google Scholar
38.Schindler, JS, Kelly, JH.Swallowing disorders in the elderly. Laryngoscope. 2002 Apr;112(4):589–602.Google Scholar
39.Sung, HY, Kim, JS, Lee, KS, et al.The prevalence and patterns of pharyngoesophageal dysmotility in patients with early stage PD. Mov Disord. 2010 Jul 28.Google Scholar
40.Menezes, C, Melo, A.Does levodopa improve swallowing dysfunction in Parkinson’s disease patients? J Clin Pharm Ther. 2009 Dec;34(6):673–6.Google Scholar
41.Baijens, LW, Speyer, R.Effects of therapy for dysphagia in PD: systematic review. Dysphagia. 2009 Mar;24(1):91–102.Google Scholar
42.Restivo, DA, Palmeri, A, Marchese-Ragona, R.Botulinum toxin for cricopharyngeal dysfunction in Parkinson’s disease. N Engl J Med. 2002 Apr 11;346(15):1174–5.CrossRefGoogle ScholarPubMed
43.Born, LJ, Harned, RH, Rikkers, LF, et al.Cricopharyngeal dysfunction in Parkinson’s disease: role in dysphagia and response to myotomy. Mov Disord. 1996 Jan;11(1):53–8.CrossRefGoogle ScholarPubMed
44.White, GN, O’Rourke, F, Ong, BS, et al.Dysphagia: causes, assessment, treatment, and management. Geriatrics. 2008 May;63(5):15–20.Google ScholarPubMed
45.Edwards, LL, Pfeiffer, RF, Quigley, EM, et al.Gastrointestinal symptoms in PD. Mov Disord. 1991;6(2):151–6.Google Scholar
46.Hardoff, R, Sula, M, Tamir, A, et al.Gastric emptying time and gastric motility in patients with PD. Mov Disord. 2001 Nov;16 (6):1041–7.Google Scholar
47.Müller, T, Erdmann, C, Bremen, D, et al.Impact of gastric emptying on levodopa pharmacokinetics in Parkinson disease patients. Clin Neuropharmacol. 2006 Mar-Apr;29(2):61–7.Google Scholar
48.Nyholm, D, Lennernäs, H.Irregular gastrointestinal drug absorption in PD. Expert Opin Drug Metab Toxicol. 2008 Feb;4(2):193–203.Google Scholar
49.Cereda, E, Barichella, M, Pedrolli, C, Pezzoli, G.Low-protein and protein-redistribution diets for Parkinson’s disease patients with motor fluctuations: a systematic review. Mov Disord. 2010 Oct 15;25(13):2021–34.Google Scholar
50.Veldhuyzen van Zanten, SJ, Flook, N, Chiba, N, et al.An evidence-based approach to the management of uninvestigated dyspepsia in the era of Helicobacter pylori. Canadian Dyspepsia Working Group. CMAJ. 2000 Jun 13;162(12 Suppl):S3–23.Google Scholar
51.Lertxundi, U, Peral, J, Mora, O, et al.Antidopaminergic therapy for managing comorbidities in patients with Parkinson’s disease. Am J Health Syst Pharm. 2008 Mar 1;65(5):414–9.Google Scholar
52.Friedenberg, FK, Parkman, HP.Delayed gastric emptying: whom to test, how to test, and what to do. Curr Treat Options Gastroenterol. 2006 Jul;9(4):295–304.Google Scholar
53.Lee, WY, Yoon, WT, Shin, HY, et al.Helicobacter pylori infection and motor fluctuations in patients with Parkinson’s disease. Mov Disord. 2008 Sep 15;23(12):1696–700.Google Scholar
54.Pierantozzi, M, Pietroiusti, A, Brusa, L, at al. Helicobacter pylori eradication and l-dopa absorption in patients with PD and motor fluctuations. Neurology. 2006 Jun 27;66(12):1824–9.Google Scholar
55.Lyte, M.Microbial endocrinology as a basis for improved L-DOPA bioavailability in Parkinson’s patients treated for Helicobacter pylori. Med Hypotheses. 2010 May;74(5):895–7.Google Scholar
56.Longstreth, GF, Thompson, WG, Chey, WD, et al.Functional bowel disorders. Gastroenterology. 2006 Apr;130(5):1480–91.Google Scholar
57.Abbott, RD, Ross, GW, White, LR, et al.Environmental, life-style, and physical precursors of clinical Parkinson’s disease: recent findings from the Honolulu-Asia Aging Study. J Neurol. 2003 Oct;250 Suppl 3:III30–9.Google Scholar
58.Savica, R, Carlin, JM, Grossardt, BR, et al.Medical records documentation of constipation preceding Parkinson disease: A case-control study. Neurology. 2009 Nov 24;73(21):1752–8.Google Scholar
59.Abbott, RD, Ross, GW, Petrovitch, H, et al.Bowel movement frequency in late-life and incidental Lewy bodies. Mov Disord. 2007 Aug 15;22(11):1581–6.Google Scholar
60.Petrovitch, H, Abbott, RD, Ross, GW, et al.Bowel movement frequency in late-life and substantia nigra neuron density at death. Mov Disord. 2009 Feb 15;24(3):371–6.Google Scholar
61.Kaye, J, Gage, H, Kimber, A, et al.Excess burden of constipation in Parkinson’s disease: a pilot study. Mov Disord. 2006 Aug;21(8):1270–3.Google Scholar
62.Krogh, K, Ostergaard, K, Sabroe, S, Laurberg, S.Clinical aspects of bowel symptoms in Parkinson’s disease. Acta Neurol Scand. 2008 Jan;117(1):60–4.Google Scholar
63.Sakakibara, R, Uchiyama, T, Yamanishi, T, et al.Bladder and bowel dysfunction in Parkinson’s disease. J Neural Transm. 2008;115 (3):443–60.Google Scholar
64.Jost, WH, Schrank, B.Defecatory disorders in de novo Parkinsonians-colonic transit and electromyogram of the external anal sphincter. Wien Klin Wochenschr. 1998 Aug 21;110(15):535–7.Google Scholar
65.Shibata, M, Morita, Y, Shimizu, T, et al.Cardiac parasympathetic dysfunction concurrent with cardiac sympathetic denervation in Parkinson’s disease. J Neurol Sci. 2009 Jan 15;276(1-2):79–83.Google Scholar
66.Ashraf, W, Pfeiffer, RF, Park, F, et al.Constipation in Parkinson’s disease: objective assessment and response to psyllium. Mov Disord. 1997 Nov;12(6):946–51.Google Scholar
67.Zangaglia, R, Martignoni, E, Glorioso, M, et al.Macrogol for the treatment of constipation in Parkinson’s disease. A randomized placebo-controlled study. Mov Disord. 2007 Jul 15;22(9):1239–44.Google Scholar
68.Soykan, I, Sarosiek, I, Shifflett, J, et al.Effect of chronic oral domperidone therapy on gastrointestinal symptoms and gastric emptying in patients with Parkinson’s disease. Mov Disord. 1997 Nov;12(6):952–7.Google Scholar
69.Jost, WH, Schimrigk, K.Long-term results with cisapride in Parkinson’s disease. Mov Disord. 1997 May;12(3):423–5.Google Scholar
70.Roarty, TP, Weber, F, Soykan, I, McCallum, RW.Misoprostol in the treatment of chronic refractory constipation: results of a longterm open label trial. Aliment Pharmacol Ther. 1997 Dec;11(6):1059–66.Google Scholar
71.Chiu, CM, Wang, CP, Sung, WH, et al.Functional magnetic stimulation in constipation associated with Parkinson’s disease. J Rehabil Med. 2009 Nov;41(13):1085–9Google Scholar
72.Mathers, SE, Kempster, PA, Swash, M, Lees, AJ.Constipation and paradoxical puborectalis contraction in anismus and PD: a dystonic phenomenon? J Neurol Neurosurg Psychiatry. 1988 Dec;51(12):1503–7.Google Scholar
73.Stocchi, F, Badiali, D, Vacca, L, et al.Anorectal function in multiple system atrophy and Parkinson’s disease. Mov Disord. 2000 Jan;15(1):71–6.Google Scholar
74.Merello, M, Leiguarda, R.Adynamic bowel syndrome in Parkinson’s disease with dramatic response to apomorphine. Clin Neuropharmacol. 17(6):574–78Google Scholar
75.Simón, MA, Bueno, AM.Behavioural treatment of the dyssynergic defecation in chronically constipated elderly patients: a randomized controlled trial. Appl Psychophysiol Biofeedback. 2009 Dec;34(4):273–7.Google Scholar
76.Rao, SS, Valestin, J, Brown, CK, et al.Long-term efficacy of biofeedback therapy for dyssynergic defecation: randomized controlled trial. Am J Gastroenterol. 2010 Apr;105(4):890–6.Google Scholar
77.Ron, Y, Avni, Y, Lukovetski, A, et al.Botulinum toxin type-A in therapy of patients with anismus. Dis Colon Rectum. 2001 Dec;44(12):1821–6.Google Scholar
78.Farid, M, El Monem, HA, Omar, W, et al.Comparative study between biofeedback retraining and botulinum neurotoxin in the treatment of anismus patients. Int J Colorectal Dis. 2009 Jan;24 (1):115–20.Google Scholar
79.Krogh, K, Christensen, P.Neurogenic colorectal and pelvic floor dysfunction. Best Pract Res Clin Gastroenterol. 2009;23(4):531–43.Google Scholar
80.Ford, B.Pain in Parkinson’s disease. Mov Disord. 2010;25 Suppl 1:S98–103.Google Scholar
81.Norton, C, Chelvanayagam, S, Wilson-Barnett, J, et al.Randomized controlled trial of biofeedback for fecal incontinence. Gastroenterology. 2003 Nov;125(5):1320–9.Google Scholar
82.Michelsen, HB, Thompson-Fawcett, M, Lundby, L, et al.Six years of experience with sacral nerve stimulation for fecal incontinence. Dis Colon Rectum. 2010 Apr;53(4):414–21.Google Scholar
83.Kulisevsky, J, Pagonabarraga, J.Tolerability and safety of ropinirole versus other dopamine agonists and levodopa in the treatment of PD: meta-analysis of randomized controlled trials. Drug Saf. 2010 Feb 1;33(2):147–61.Google Scholar
84.Hauser, RA, Panisset, M, Abbruzzese, G, et alon behalf of the FIRST-STEP Study Group. Double-blind trial of levodopa/carbidopa/entacapone versus levodopa/carbidopa in early PD. Mov Disord. 2009 Mar 15;24(4):541–50.Google Scholar
85.Chen, JJ, Swope, DM, Dashtipour, K.Comprehensive review of rasagiline, a second-generation monoamine oxidase inhibitor, for the treatment of PD. Clin Ther. 2007 Sep;29(9):1825–49.CrossRefGoogle Scholar
86.No authors listed. Amantadine. In: McEvoy, G.K, editor. American Hospital Formulary Service-Drug Information 2005. Bethesda: American Society of Health-System Pharmacists; 2005. p. 592Google Scholar
87.French, J, Gronseth, G.Lost in a jungle of evidence: we need a compass. Neurology. 2008 Nov 11;71(20):1634–8.Google Scholar
88.Gronseth, G, French, J.Practice parameters and technology assessments: what they are, what they are not, and why you should care. Neurology. 2008 Nov 11;71(20):1639–43.CrossRefGoogle Scholar
89.Zesiewicz, TA, Sullivan, KL, Arnulf, I, et alon behalf of the Quality Standards Subcommittee of the American Academy of Neurology. Practice Parameter: treatment of nonmotor symptoms of Parkinson disease: report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology. 2010 Mar 16;74(11):924–31.Google Scholar
90.Horstink, M, Tolosa, E, Bonuccelli, U, et alon behalf of the European Federation of Neurological Societies and the Movement Disorder Society-European Section. Review of the therapeutic management of Parkinson’s disease. Report of a joint task force of the European Federation of Neurological Societies (EFNS) and the Movement Disorder Society-European Section (MDSES). Part II: late (complicated) Parkinson’s disease. Eur J Neurol. 2006 Nov;13(11):1186–202.Google Scholar
91.Goetz, CG, Tilley, BC, Shaftman, SR, et alon behalf of the Movement Disorder Society UPDRS Revision Task Force. Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS): scale presentation and clinimetric testing results. Mov Disord. 2008 Nov 15;23(15):2129–70.Google Scholar
92.Chaudhuri, KR, Martinez-Martin, P, Schapira, AH, et al.International multicenter pilot study of the first comprehensive self-completed nonmotor symptoms questionnaire for Parkinson’s disease: the NMSQuest study. Mov Disord. 2006 Jul;21(7):916–23.Google Scholar
93.Chaudhuri, KR, Martinez-Martin, P, Brown, RG, et al.The metric properties of a novel non-motor symptoms scale for Parkinson’s disease: Results from an international pilot study. Mov Disord. 2007 Oct 15;22(13):1901–11.Google Scholar
94.Visser, M, Marinus, J, Stiggelbout, AM, Van Hilten, JJ.Assessment of autonomic dysfunction in Parkinson’s disease: the SCOPA-AUT. Mov Disord. 2004 Nov;19(11):1306–12.Google Scholar
95.Perez Lloret, S, Pirán Arce, G, Rossi, M, et al.Validation of a new scale for the evaluation of sialorrhea in patients with PD. Mov Disord. 2007 Jan;22(1):107–11.Google Scholar
96.McHorney, CA, Bricker, DE, Kramer, AE, et al.The SWAL-QOL outcomes tool for oropharyngeal dysphagia in adults: I. Conceptual foundation and item development. Dysphagia. 2000 Summer;15(3):115–21.Google Scholar
97.McHorney, CA, Bricker, DE, Robbins, J, et al.The SWAL-QOL outcomes tool for oropharyngeal dysphagia in adults: II. Item reduction and preliminary scaling. Dysphagia. 2000 Summer;15 (3):122–33.Google Scholar
98.McHorney, CA, Robbins, J, Lomax, K, et al.The SWAL-QOL and SWAL-CARE outcomes tool for oropharyngeal dysphagia in adults: III. Documentation of reliability and validity. Dysphagia. 2002 Spring;17(2):97–114.Google Scholar
99.Agachan, F, Chen, T, Pfeifer, J, et al.A constipation scoring system to simplify evaluation and management of constipated patients. Dis Colon Rectum. 1996 Jun;39(6):681–5.Google Scholar