Alternative TXs not well studied
A high-quality systematic review6 of constipation management among adults of all ages in North America found a lack of quality RCTs examining herbal supplement treatment. Biofeedback has been studied in adult populations, but no RCTs with placebo or sham-controls have been published.
One before-after cohort study7 investigated an external kneading mechanical device (Free-Lax) that was applied to the abdomen for 20 minutes once daily in 30 randomly selected chronically constipated nursing home residents. Researchers found significant improvements in bowel movement frequency, stool consistency and volume, and colonic transit time without side effects (TABLE).
A look beyond geriatric patients
Polyethylene glycol, tegaserod, and lubiprostone have not been studied in trials of exclusively geriatric populations. Two high-quality systematic reviews,6,8 including medium- to high-quality RCTs of pharmacologic management of chronic constipation, found good evidence to support treatment with polyethylene glycol and tegaserod in adults of all ages. Of the 8 RCTs looking at polyethylene glycol, only 1 of the studies—a high-quality crossover comparison of polyethylene glycol vs placebo with 37 out-patient subjects—included a population with a mean age >60 years (mean age 62, range 42–89 years).
TABLE
How well do these interventions work for older patients with chronic constipation?
| INTERVENTION VS COMPARISON | STOOL FREQUENCY (STOOLS PER WEEK) | NNT‡ |
|---|---|---|
| Agiolax* vs lactulose | 4.5 vs 2.2 | 43 |
| Agiolax* vs lactulose | 5.6 vs 4.2 | 71 |
| Lactitol† vs placebo | 4.9 vs 3.6 | 77 |
| Lactitol† vs lactulose | 5.5 vs 4.9 | 160 |
| Lactulose vs sorbitol† | 7.0 vs 6.7 | 330 |
| External abdominal kneading (before-after) | 3.9 vs 1.4 | 40 |
| * Agiolax is a combination bulk and stimulant laxative not readily found in the United States. | ||
| † Lactitol and sorbitol are sugar alcohols used as replacement sweeteners and approved by the FDA as food additives. | ||
| ‡ Number needed to treat (NNT) for 1 person to have 1 more stool per week. | ||
A subgroup analysis9 of 331 elderly patients enrolled in 2 RCTs of tegaserod found no difference in outcomes between treatment with tegaserod and placebo, although this analysis was limited by inadequate power.
Tegaserod linked to ischemic events. A recent analysis of clinical trials found a statistically significant increase in cardiovascular ischemic events associated with tegaserod. The manufacturer took the product off the market in compliance with an FDA request in March 2007.
Lubiprostone offers promise. Lubiprostone, a chloride channel activator approved by the FDA for the treatment of chronic idiopathic constipation, has been studied in 6 placebo-controlled, double-blind, randomized Phase II and III clinical trials. In 2 unpublished pooled analyses of 3 of the trials, lubiprostone was found to be effective in a total of 220 elderly patients 65 years of age and older.10,11
Recommendations from others
The American College of Gastroenterology Chronic Constipation Task Force evidence-based guidelines make no reference to age, but state that evidence is best for treatment with psyllium, tegaserod, polyethylene glycol, and lactulose.12 They found insufficient evidence to support use of stimulants, stool softeners, lubricants, herbal supplements, biofeedback, and alternative treatments.
The American Gastroenterological Association guidelines on constipation are primarily based on expert opinion.13 Age is not specified in their recommendations. Dietary and exercise modifications are recommended as first-line treatments, followed by laxatives. Laxatives are recommended based on cost, in order from the least to most expensive agents. Suppositories, enemas, biofeedback, and (in refractory cases) surgery are recommended for patients with pelvic floor dysfunction.
The Registered Nurses Association of Ontario guidelines for constipation prevention in the older adult population recommend fluid and dietary fiber, regular exercise, and consistent toileting.14