Constipation Causes in the Elderly

1. See Also
   1. Constipation
   2. Constipation Causes
   3. Organic Constipation
   4. Functional Constipation
   5. Drug-Induced Constipation
2. Epidemiology: Prevalence
   1. Constipation in Adults over age 60 years: 33%
   2. Constipation in Nursing Home residents: >50%
3. Pathophysiology: Types
   1. Normal Transit Constipation (most common)
      1. Normal stool frequency, but hard consistency
   2. Slow Transit Constipation
      1. Bowel Myopathy or Neuropathy
      2. Infrequent Defecation with bloating and Abdominal Pain
   3. Disorders of Defecation (common in elderly)
      1. Decreased rectal smooth muscle contraction or relaxation
      2. Decreased stooling urge response to rectal sensation of Stretching
      3. Consult gastroenterology
4. Symptoms
   1. Straining during Defecation
   2. Difficult stool evacuation
   3. Intermittent paradoxical Diarrhea
      1. Liquid stool leaks around impacted stool
5. Risk Factors
   1. Dehydration
   2. Immobility (especially with Arthritis)
6. Causes
   1. Consider Constipation red flags (high risk population for Colon Cancer)
   2. See Constipation Causes
   3. See Organic Constipation
   4. Functional causes
      1. Rectal Outlet Constipation
   5. Secondary Constipation
      1. See Secondary Constipation
      2. Autonomic Neuropathy
         1. Diabetes Mellitus
         2. Parkinson Disease
      3. Other neurologic disorders
         1. Dementia
         2. Decreased sensation to defecate (risk for impaction)
         3. Spinal cord disorders
      4. Medications
         1. See Drug-Induced Constipation
         2. Opioids (see Opioid-Induced Constipation)
         3. Anticholinergic Medications
7. Management
   1. See Constipation Management
   2. Constipation due to disorders of Defecation should be referred to Gastroenterology
   3. Goals
      1. Clear Fecal Impaction first
      2. Improve symptoms (bloating, pain)
      3. Soft, formed stool without straining 3 times weekly or more
   4. Behavioral measures
      1. Straighten anorectal junction by placing feet on step stool while sitting on toilet
      2. Allow patient time and privacy to stool without interruption
      3. Encourage adequate hydration (48 to 64 ounces or 1.5 to 2 Liters daily)
      4. Encourage adequate fiber intake such as Metamucil or Citrucel (20-35 g/day)
         1. See Dietary Fiber
         2. Delay start until Acute Constipation has resolved and hydration is adequate
         3. Gradually increase over the course of weeks and decrease if cramps, bloating occur
      5. Biofeedback
         1. Pelvic Floor Exercises
         2. Retrain Defecation muscles
      6. Ineffective measures
         1. Probiotics are not effective
         2. Chmielewska (2010) World J Gastroenterol 16(1): 69-75 [PubMed]
   5. Disimpaction
      1. Perform rectal exam to confirm no firm impaction resulting in obstruction
         1. Manually disimpact first
      2. Preferred options
         1. Mineral Oil enemas
         2. Tap water enema
         3. Glycerin suppository
      3. Avoid measures with adverse effects in older adults
         1. Phosphate enemas such as Fleets Enema (risk of electrolyte abnormalities)
         2. Soap sud enema (risk of rectal mucosa injury)
   6. Laxatives
      1. Bulk Laxatives
         1. See fiber above under behavioral measures
      2. Osomotic Laxatives
         1. Polyethylene glycol (Miralax, PEG Solution) 1/2 to 1 capful daily in 4-8 ounces juice
         2. Exercise caution with Magnesium salts (e.g. Magnesium Citrate)
            1. Risk of Magnesium toxicity (and ileus)
            2. Consider single Magnesium Citrate 150-300 ml use after initial disimpaction
      3. Stool Softeners
         1. DocusateSodium (Colace) 100 mg orally twice daily (or 200 mg at night)
         2. Effective in older adults, despite underwhelming effects in other populations
      4. Stimulant Laxatives
         1. Senna 15 mg daily or Bisacodyl (Dulcolax) 5-15 mg daily
         2. Longterm Stimulant Laxative use is not recommended (unless refractory to other measures)
   7. Other agents for refractory Constipation (expensive)
      1. See Opioid-Induced Constipation
      2. Lubiprostone (Amitiza) 24 mcg twice daily (Nausea in 18%)
      3. Linaclotide (Linzess) 145 mcg daily (Diarrhea in 16%)
8. References
   1. Mounsey (2015) Am Fam Physician 92(6): 500-4 [PubMed]
   2. Fleming (2010) Am J Geriatr Pharmacother 8(6): 514-50 [PubMed]