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Biomedical subjects

M D Crowell

Publications and source records attributed to M D Crowell.

At least 37 records · Page 2Linked to original sources
PubMed1995

Gastrointestinal symptoms in bulimia nervosa: effects of treatment.

OBJECTIVES: The aim of this study was to characterize the frequency and severity of gastrointestinal symptoms in bulimic patients and to determine their response to treatment of the eating disorder. METHODS: Forty-three consecutive bulimic patients admitted to the inpatient Eating Disorders Unit of the Psychiatry Service were asked to fill out a gastrointestinal symptoms questionnaire, an Eating Disorders Inventory, and a Zung Depression Inventory on admission and discharge. Thirty-two age- and sex-matched healthy volunteers completed the same questionnaire. RESULTS: In bulimic patients, the most commonly reported gastrointestinal symptoms were bloating (74.4%), flatulence (74.4%), constipation (62.8%), decreased appetite (51.2%), abdominal pain (48.8%), borborygmi (48.8%), and nausea (46.5%). The average symptom score (sum of severity ratings) on the gastrointestinal symptoms questionnaire decreased from 20.6 +/- 10.8 (mean +/- SD) on admission to 13.46 +/- 10.5 (t(27) = 3.31, p < 0.01) on discharge but remained significantly higher than that of the control group (4.4 +/- 6.2, t(43) = 4.02, p < 0.001). However, the severity of reported gastrointestinal symptoms was correlated with the severity of depression (r = 0.43, p < 0.05), and when the possible mediating effects of depression on gastrointestinal symptoms were controlled statistically (analysis of covariance), the effects of treatment on gastrointestinal symptoms were not statistically significant. CONCLUSION: Gastrointestinal symptoms in bulimics are common, multiple, and often severe and they improve with treatment. However, the most important determinant of gastrointestinal symptoms appears to be depression.

Abdominal Pain↗
PubMed1994

Nutrient ingestion increases rectal sensitivity in humans.

To determine the effect of nutrient ingestion on rectal perception thresholds (first sensation, consistent urge to defecate, pain), rectosigmoid balloon distentions were performed with a computerized automated pump in eight healthy volunteers (four males, four females, 31.6 +/- 6.02 years). Two measurements of rectal balloon distention were performed on 2 separate days. Day 1 served as a control condition with no meal. On day 2 the subjects received a 600 kcal liquid meal. On the control day, determination of perception thresholds was performed two times with a 10-min break between measurements. On the experimental day, threshold determinations were made before and after the ingestion of the liquid standard meal. The order of the experimental days was counterbalanced. Distention volumes at the urge to defecate and the pain threshold (maximum tolerable volume) were significantly reduced following the meal. The average change from pre- to postprandial measurements of the threshold for urge to defecate was -20.55 +/- 4.22% and for the maximum tolerable volume it was -16.09 +/- 4.4%. These results extend data previously reported from animal studies using similar experimental methods.

Adult↗
PubMed1994

Effect of rectal distention and feeding on cecal tone in pigs.

The effects of eating and rectal distention on cecal tone were evaluated. Cecal tone was measured using a computer-controlled barostat in four female 30 to 40 kg Yucatan Micropigs fitted with cecal fistulas. Each pig underwent two separate trials of pre and postprandial measurements of cecal tone, either with or without continuous rectal distention with a 30 ml water-filled balloon. Cecal tone was measured 10 min prior to, during, and 10 min following a high-fat (60%) liquid meal (473 ml). Cecal tone significantly increased (intrabag volume decreased) after feeding (119.6 +/- 9.1 ml vs. 81.2 +/- 7.9 ml; p = 0.008). Rectal distention tended to reduce the postprandial change in cecal tone (142.8 +/- 11.5 vs. 130.9 +/- 12.6 ml; p = 0.196). There was also a strong tendency for cecal volumes to be higher (decreased tone) with rectal distention preprandially (142.8 +/- 11.5 ml vs. 119.6 +/- 9.1 ml; p = 0.024). Nutrient ingestion significantly increased cecal tone and rectal distention abolished this effect. These findings may indicate a regulatory pathway that allows additional storage of fecal material in the event that the output of the system is disturbed.

Animals↗
PubMed1994

Functional bowel disorders in women with dysmenorrhea.

OBJECTIVES: The relationship between menstrual and bowel symptoms, the overlap between the diagnoses of dysmenorrhea (DYS) and functional bowel disorder (FBD), and markers that may be useful in discriminating functional bowel disorders from DYS were studied in 383 women (20-40 yr of age). METHODS: All women completed the NEO Personality Inventory at intake and completed the Moos' Menstrual Distress Questionnaire and a bowel symptom inventory every 3 months for 12 months. Prostaglandin levels were measured in vaginal dialysate on the first day of menses. RESULTS: DYS was diagnosed in 19.8% of the total sample. Functional bowel disorder, defined as abdominal pain with altered bowel function, was diagnosed in 61% of the DYS group compared with 20% of controls (p < 0.05). Neuroticism scores were significantly higher in subjects with functional bowel disorder with or without DYS. However, bowel symptoms were significantly correlated with menstrual symptoms even after statistically controlling for the effects of neuroticism. Painful menses and water retention distinguished the DYS group from the functional bowel disorder group. Prostaglandin levels were elevated in women with DYS, but did not consistently differentiate the diagnostic groups. CONCLUSIONS: The strong covariation of menstrual and bowel symptoms, along with the overlap in diagnoses of DYS and function bowel disorder, suggest a common physiological basis.

Adult↗
PubMed1994

Prevalence of gastrointestinal symptoms in obese and normal weight binge eaters.

OBJECTIVES: Disturbances in gastrointestinal function may result from disordered eating and may lead to increases in gastrointestinal (GI) symptoms. We compared GI symptoms in obese and non-obese binge eaters and non-binge eaters. METHODS: One hundred nineteen obese and 77 normal-weight females completed a questionnaire on bowel symptoms and binge eating behaviors for the previous 3 months. Based on binge behaviors and body mass index (> 30 kg/m2), individuals were grouped as obese binge eaters (n = 73), obese non-binge eaters (n = 43), non-obese binge eaters (n = 14), and normal-weight controls (n = 61). RESULTS: Obese binge eaters reported more upper GI symptoms than normal controls or obese non-binge eaters (p < 0.001). Compared with normal controls, nausea, vomiting, and bloating was 2-4 times more prevalent in both binge eating groups. Indigestion was more prevalent in both obese groups. Obese binge eaters reported more lower GI symptoms than normal-weight controls (p < 0.05). Binge eating in both weight groups was associated with more frequent abdominal pain and dyschezia. Obesity was associated with more frequent constipation, diarrhea, straining, and flatus, whether or not subjects reported binge eating. Chi-square showed a significant association between obesity, binge eating, and symptoms of irritable bowel syndrome, using the Manning criteria. CONCLUSIONS: Specific GI symptoms were associated with binge eating and obesity. Overall, symptoms were more prevalent and more severe in obese binge eaters. The high prevalence of GI symptoms in obese patients who indulge in binge eating should be considered in their evaluation and treatment.

Analysis of Variance↗
PubMed1993

Eating lowers defecation threshold in pigs through cholinergic pathways.

The effect of atropine on defecation threshold was compared to placebo pre- and postprandially in four 20- to 30-kg pigs. Stepwise balloon distention was performed 10 cm from the anal verge with a 5-cm latex balloon. Volume was increased in steps of 10 ml up to 200 ml of air or until the balloon was defecated (defecation threshold). Dependent measures were balloon volume, rectal pressure, rectal compliance, and an index of distention-induced contractile activity. Under placebo conditions, the volume and pressure to elicit defecation were significantly lower after feeding (p < 0.05). The distention-induced contractile activity significantly increased near the defecation threshold, but pre- and postprandial conditions were not different. No differences were seen between pre- and postprandial rectal compliance curves. Atropine abolished the postprandial decrease in defecation threshold, but did not affect rectal compliance. The increase in contractile activity at defecation threshold seen with placebo was abolished by atropine. These results show that eating lowers the defecation threshold in terms of distention volume and rectal pressure, and demonstrate that these changes are mediated through cholinergic pathways.

Animals↗
PubMed1993

Contractile activity of the human colon: lessons from 24 hour studies.

The motor function of the colon is probably the least understood of the various hollow viscera of the human body. This is partly because of the marked variability of colonic motor function and the short recording periods usually used, generally not exceeding three hours. Most of the data available on human colonic motility originate from investigations conducted in the most distal portions of the viscus, because of technical difficulties in reaching its proximal portions. Although attempts have been made to solve these problems through the ingestion of radiotelemetric pressure sensors, these efforts have been hampered by intermittent signal loss and the inability to control the location of the capsule within the gastrointestinal tract. To overcome these problems, techniques have recently been developed that permit prolonged recordings (24 hours or more) of myoelectrical and contractile activity of the human colon, with both perfused and solid-state manometric systems. The present paper reviews the current experience in 24 hour recording from the human colon, with a primary emphasis on the more forceful propulsive contractile activity associated with the so called mass movements.

Circadian Rhythm↗
PubMed1992

The effect of feeding on defecation behaviour in pigs.

The effect of eating on defecation behaviour was investigated in four 20-30 kg pigs. Rectal distention stimulation was performed pre- and postprandially at 10 cm from the anus with a 5 cm latex balloon. Volume was increased in steps of 10 ml up to 200 ml of air or until balloon defecation. Dependent measures were volume, rectal pressure, determined with a solid state pressure transducer inside the balloon probe, rectal compliance, and an index of distention induced contractile activity. The volume and pressure required to elicit defecation was significantly lower after feeding (p less than 0.01). Distention induced contractile activity was significantly increased near defecation threshold, but pre- and postprandial conditions were not different. There was no difference in rectal compliance pre- and postprandially. These results suggest that eating lowers defecation threshold in terms of distention volume and rectal pressure, and that these changes are not dependent on altered rectal compliance or changes in distention induced motor activity.

Animals↗
PubMed1992

Prolonged ambulatory monitoring of colonic motor activity in the pig.

The aim of this study was to develop a chronic model suitable for repeated, long-term studies of the interaction of behavior and colonic function in unrestrained pigs. Cecostomies were created in three 20-30 kg micropigs under general anesthesia. Fistulas were created by suturing the bowel to the abdominal wall. Recordings were made by passing a small (8F) solid-state pressure transducer through the fistula into the proximal bowel and connecting it to a battery-operated data logger worn in a vest on the pig's back. Cecostomies have remained patent and trouble-free for over 18 months. No serious infections have occurred. Preliminary data from a total of thirteen 24-h recording sessions showed 54% of all contractile activity to be in the 2-4 cpm frequency range. Increased motility was seen following meals and upon morning awakening. Motility was minimal during the night. Infrequent (10.31 +/- 2.05/24 h; mean +/- SD) propagated contractions were also noted. These contractions were generally of low amplitude (33.24 +/- 3.81 mmHg). These techniques allow prolonged, intraluminal recordings to be made from the colon of the unrestrained pig.

Animals↗
PubMed1992

Effect of prolonged, continuous rectal distention on mouth-to-cecum and colonic transit time in pigs.

The effect of prolonged (6 h), continuous rectal distention on mouth-to-cecum and colonic transit time was studied in four unrestrained pigs. Mouth-to-cecum transit time was determined from samples of cecal efflux using the phenol red dye technique. Colonic transit time was assessed with radiopaque markers that were injected into the cecum before each trial. Rectal distention was applied 2-1/2 h before feeding, during feeding, and 3-1/2 h after feeding. No distention was applied during control conditions. Stools were collected for 48 h after marker application. Rectal distention increased mouth-to-cecum transit time (p < 0.05). Colonic transit time was also prolonged by rectal distention as shown by a significant decrease in the number of markers excreted within 36 h (p < 0.05). Rectal distention for 6 h increased colonic transit time up to 30 h following distention and prolonged mouth-to-cecum transit of a high fat liquid meal.

Animals↗
PubMed1992

Effects of stressful life events on bowel symptoms: subjects with irritable bowel syndrome compared with subjects without bowel dysfunction.

A standardised inventory of stressful life events and a bowel symptom questionnaire were administered at three month intervals for one year to 383 women who were unselected with respect to bowel symptoms. A NEO Personality Inventory was given initially to assess neuroticism. Subjects who satisfied restrictive diagnostic criteria for irritable bowel syndrome were compared with those who complained of abdominal pain plus altered bowel habits but who did not meet restrictive diagnostic criteria (functional bowel disorder) and with controls without bowel dysfunction. The irritable bowel group showed significantly higher levels of stress than the other two groups even when the confounding effects of neuroticism were statistically controlled for. Time lagged correlations showed that stress in one three month interval was significantly correlated with bowel symptoms in the subsequent three month interval for all groups. The slope of the regression line relating stress to bowel symptoms was significantly steeper for the irritable bowel group than for the other two groups at three and six months, suggesting that subjects with irritable bowel syndrome show a greater reactivity to stress. Stress scores were also significantly correlated with the number of disability days and the number of medical clinic visits for bowel symptoms.

Adult↗
PubMed1991

Method for prolonged ambulatory monitoring of high-amplitude propagated contractions from colon.

This study monitored high-amplitude propagated contractions (HAPCs) in ambulating subjects over a 24-h period using a new ambulatory recording system. Twelve healthy volunteers aged 34 +/- 5.96 yr participated. Approximately 12 h after a Colyte bowel prep, a small catheter (OD less than 3 mm), containing three solid-state pressure transducers spaced 5 cm apart, was positioned by flexible sigmoidoscope at 40-50 cm from the anal verge. A battery-operated data recorder sampled the pressure at each port at 1 Hz and stored the values on all ports if any port exceeded 75 mmHg. At the conclusion of the 24-h period, an X-ray was taken to confirm the location of the catheter. Fifty-four percent of all HAPCs preceded a bowel movement by less than or equal to 1 h. Forty-nine percent of all HAPCs occurred within 1 h after a high-fat meal, and 33% occurred within 1 h of morning awakening. Reverse propagated waves, not previously described in the colon, were observed in three individuals. Spontaneous high-amplitude caudally propagated contractions occur 6.9 +/- 1.5 times/24 h in the sigmoid colon in ambulating asymptomatic individuals and are temporally related to defecation and meals. Peristaltic activity is decreased during sleep. This recording technique was reliable and well tolerated in all participants.

Adult↗
PubMed1991

Psychologic considerations in the irritable bowel syndrome.

Among medical clinic patients consulting for IBS, symptoms of psychologic distress are common, and more than half of these patients are found to have a psychiatric diagnosis in addition to bowel dysfunction. Many investigators have therefore concluded that IBS is a psychophysiologic disorder and proposed that patients with IBS be treated with psychologic techniques. However, recent studies suggest that this association may be spurious; persons in the community who have symptoms of IBS but do not consult a doctor have no more psychologic symptoms than persons without bowel symptoms. This indicates that psychologic symptoms do not cause bowel symptoms, but, instead, influence which persons with bowel symptoms will consult a physician. The bowel symptoms and the psychologic symptoms that coexist in most patients with IBS may be best thought of as comorbid conditions. Neither causes the other, but both may be serious enough to warrant treatment. Moreover, in some patients whose bowel symptoms consist of vague complaints of abdominal pain not specifically related to defecation or to changes in the frequency or consistency of bowel habits, the psychologic disorder may be primary. Psychologic stress may exacerbate IBS whether or not the patient has a psychiatric disorder, and psychologic stress may trigger acute episodes of symptoms similar to those of IBS even in persons without IBS. However, the magnitude of this correlation is modest, suggesting that only about 10% of the variation in bowel symptoms is attributable to stress. Psychologically oriented treatments have a role in the management of IBS. Most patients who consult internists about bowel symptoms have significant levels of depression and anxiety, and they tend to notice and to worry about somatic complaints more when they experience these dysphoric affects. Psychologic treatments that reduce the level of their psychologic distress also frequently reduce the frequency and severity of complaints about bowel symptoms. Tricyclic antidepressants may be tried as a first line of treatment; they have been shown to be superior to placebo for the management of abdominal pain and diarrhea but not constipation. In patients who do not show an adequate response to antidepressants, brief psychotherapy focusing on better ways of coping with current problems, hypnosis, or behavior therapy emphasizing methods of controlling reactions to stress are recommended. Controlled trials show these treatment approaches to be superior to medical management alone. It may appear paradoxical that psychologic treatments aimed at the management of emotions are so frequently found to reduce bowel symptoms, because the motility disorder responsible for the bowel symptoms may be unrelated to the psychologic symptoms that influence the patient to seek treatment.+4

Antidepressive Agents↗
PubMed1990

Existence of irritable bowel syndrome supported by factor analysis of symptoms in two community samples.

To determine whether bowel symptoms covary in a pattern consistent with the existence of irritable bowel as a distinct syndrome, bowel symptom questionnaires from 2 independent samples were factor analyzed. Samples consisted of 351 18-40-yr-old women who visited Planned Parenthood clinics for contraception and 149 18-89-yr-old women recruited through church women's societies. Factor analysis of 23 bowel symptoms identified 4 factors (clusters of symptoms that were correlated with each other) in both samples. The factor accounting for the most variance in both samples included relief of pain with defecation, looser stools with pain onset, more frequent stools with pain, and gastrointestinal reactions to eating. This irritable bowel factor was not correlated with an objective measure of lactose intolerance. An independent constipation factor was found in both samples to include self-reported constipation, straining with bowel movements, feeling of incomplete evacuation, and rectal bleeding. Thus factor analysis of bowel symptoms supports the existence of a specific irritable bowel syndrome and suggests symptoms that may be used to diagnose this syndrome.

Adult↗
PubMed1990

Evidence for exacerbation of irritable bowel syndrome during menses.

Many women report that bowel symptoms are associated with menstruation, but neither the prevalence of these complaints nor their physiological basis is known. This study aimed to estimate prevalence, to determine whether patients with irritable bowel syndrome are more likely to make such complaints, and to determine whether bowel complaints during menstruation are attributable to psychological traits such as increased somatization. To estimate prevalence, 369 clients of Planned Parenthood of Maryland were asked whether gas, diarrhea, or constipation occurred during menstruation. These subjects were compared with women referred to a gastroenterology clinic and found to have irritable bowel syndrome or functional bowel disorder (abdominal pain plus altered bowel habits but not satisfying restrictive criteria for irritable bowel syndrome). Thirty-four percent of 233 Planned Parenthood clients who denied symptoms of irritable bowel syndrome or functional bowel disorder reported that menstruation was associated with one or more bowel symptoms. Gastroenterology clinic patients with irritable bowel syndrome were significantly more likely to experience exacerbations of each of these bowel symptoms, but especially increased bowel gas. Self-reports of bowel symptoms during menstruation were not associated with psychological traits or with menses-related changes in affect.

Abdominal Pain↗
PubMed1989

Patterns of autonomic response during laboratory stressors.

The present study was designed to include an index reflecting the influence of parasympathetic nervous system activity on the heart, respiratory sinus arrhythmia, in addition to measures reflecting primarily sympathetic nervous system activity. The inclusion of the parasympathetic index was considered important for two reasons:(a) Past studies have suggested different patterns of autonomic response to qualitatively different laboratory stressors but have had to infer parasympathetic influences more indirectly, and (b) there is evidence that borderline hypertensives may have reduced vagal tone at rest when compared to normotensives. This last point is important for the study of individual differences in cardiovascular reactivity because excessive responsiveness in young normotensives (beta-adrenergic reactors) has been suggested as a model for studying the precursors of some types of hypertension. Fifty-one male college students were given a reaction time task, a mental arithmetic task, a cold pressor task, and graded bicycle exercise. A variety of cardiovascular and respiratory measures were collected on each subject. Results indicated significant differences in levels of respiratory sinus arrhythmia during the three tasks and the rest period, giving additional evidence for parasympathetic differences (along with sympathetic differences) in these conditions. Additionally, high beta-adrenergic reactors did not differ in mean level of respiratory sinus arrhythmia from low reactors either at rest or during the task periods. These results are discussed in the context of previous research.

Adult↗
PubMed1987

Stability of cardiovascular reactivity to laboratory stressors: a 2 1/2 yr follow-up.

The temporal stability of cardiovascular reactivity to laboratory stressors over a 2 1/2 yr period was studied. Subjects who had earlier received a cold pressor and a shock avoidance reaction time task were brought back for retesting using almost identical tasks. Cardiovascular variables that were common to both sessions included heart rate, systolic and diastolic blood pressure, and pre-ejection period. Correlations were computed to examine the association of responses across both sessions for the four cardiovascular variables during rest and the two tasks. Correlations of both heart rate and systolic blood pressure were high for all tasks and rest, whereas inconsistent correlations were found for diastolic pressure and pre-ejection period. Inconsistencies in diastolic pressure are speculated to be due to individual differences in beta-adrenergic response, whereas lack of consistent pre-ejection period associations may be due to differences in methodology. The results generally support the assumption of stability of cardiovascular reactivity.

Adult↗