Oral contraceptives and gastrointestinal disorders

Occlusive vascular diseases in oral contraceptive users. Epidemiology, pathology and mechanisms

Despite being an unprecedented departure from normal physiology, the combined oral contraceptive is not only highly effective, but it also has a remarkably good safety record. Concerns over safety persist, though, particularly with regard to venous thromboembolism (VTE), stroke and myocardial infarction (MI). Epidemiological studies consistently show an increase in risk of VTE, but the results are more contentious with regard to arterial diseases. Despite 40 years of research, the mechanisms behind these adverse effects are not understood. In this review, we integrate information from published studies of the epidemiology and pathology of the occlusive vascular diseases and their risk factors to identify likely explanations for pathogenesis in oral contraceptive users. Oral contraceptives induce both prothrombotic and fibrinolytic changes in haemostatic factors and an imbalance in haemostasis is likely to be important in oral contraceptive-induced VTE. The complexity of the changes involved and the difficulty of ascribing clinical significance has meant that uncertainty persists. A seriously under-researched area concerns vascular changes in oral contraceptive users. Histologically, endothelial and intimal proliferation have been identified in women exposed to high plasma estrogen concentrations and these lesions are associated with thrombotic occlusion. Other structural changes may result in increased vascular permeability, loss of vascular tone and venous stasis. With regard to arterial disease risk, epidemiological information relating to dose effects and joint effects with other risk factors, and studies of pathology and changes in risk factors, suggests that oral contraceptive use per se does not cause arterial disease. It can, nevertheless, synergise very powerfully with subclinical endothelial damage to promote arterial occlusion. Accordingly, the prothrombotic effects of the oral contraceptive estrogen intervene in a cycle of endothelial damage and repair which would otherwise remain clinically silent or would ultimately progress - in, for example, the presence of cigarette smoking or hypertension - to atherosclerosis. Future work in this area should focus on modification of the effects of established risk factors by oral contraceptive use rather than modification of the supposed risk of oral contraceptive use by established risk factors. Attempts to understand vascular occlusion in oral contraceptive users in terms of the general features of VTE or with reference to atherosclerosis may be limiting, and future work needs to acknowledge that such occlusions may have unique features. Unequivocal identification of the mechanisms involved would contribute considerably to the alleviation of fears over vascular disease and to the development of even safer formulations.

Oral contraceptive-induced mesenteric venous thrombosis with resultant intestinal ischemia

The author reports a case of oral contraceptive-induced mesenteric venous thrombosis with resultant intestinal ischemia in a young woman. The relationship between mesenteric venous thrombosis and oral contraceptives is discussed. Twenty-six other cases of oral contraceptive-related mesenteric venous thrombosis reported in the English literature are reviewed.

Young woman's digestive arterial occlusion--a case report and literature review

The authors report the observation of a 31-year-old woman who presented with total occlusion of digestive arteries and was successfully treated pharmacologically. A review of the literature shows that digestive arteries thrombosis is a rare condition in young women. Only 15 cases have been previously reported. Prognosis was poor with a mortality rate of 71%; 93% used oral contraception and more than 50% were smokers. All these cases were curiously similar. The authors accentuate the role of iloprost in the recovery of the patient. Digestive artery occlusion should be taken into consideration in the differential diagnosis of abdominal pain, especially in young women who smoke and take estrogen-containing birth control pills.

Drug-related segmental colitis: angiographic findings

We report a case of drug-related segmental colitis in a 70-year-old woman with no thromboembolic risk factor. Mesenteric angiography showed multiple stenoses and occlusions of the distal arterial circulation in the sigmoid and descending colon. These observations support the hypothesis of an ischemic origin for this type of colitis.

Clinical features in young adult patients with ischaemic colitis

The clinical, radiographic and endoscopic findings in 16 patients with ischaemic colitis, all of whom were < 45 years of age, were analysed. The clinical features were characterized by an acute onset of abdominal pain and rectal bleeding, and persistent constipation prior to the onset of symptoms. Twelve of the 16 patients did not have any known predisposing factors. Barium enema examination and colonoscopy revealed longitudinal ulcers and oedema of the left side of the colon of these patients. These features were then compared with those found in patients with ischaemic colitis, who were > 70 years of age. Although the clinical symptoms, the site of involvement and the initial radiographic or endoscopic findings were similar between the two groups, the transient form of ischaemic colitis and constipation prior to the onset of symptoms were more frequently present in the young patients than in the old patients. These findings suggest that ischaemic colitis, which is not a rare condition even in young adults, is less severe in young patients than in old patients, and that constipation may be related to the pathogenesis of this disease in young adults.

Oral contraceptive use and cigarette smoking in Crohn's disease

Previous studies have consistently found strong positive associations between smoking and Crohn's disease. The association between oral contraceptive use and Crohn's disease remains, however, controversial. In order to analyze whether smoking and oral contraceptive use are independent risk factors, a case-control study was performed. In 90 women with Crohn's disease and 90 community controls information was assessed about their smoking habits and their use of oral contraceptives. Smoking and oral contraceptive use were associated with one another. After adjusting for oral contraceptive use, the relative risk for smokers compared with nonsmokers was 3.0 (1.3-6.8). After controlling for smoking, the relative risk estimates for oral contraceptive use were for no use, 1-3 years, and > 3 years of use 1.0, 2.5 (1.0-6.6), and 4.3 (1.3-14.4), respectively. When oral contraceptive use was stratified by smoking habits, the data show that oral contraceptives only increased the risk for Crohn's disease in nonsmokers. From the lack of increase in risk for combined exposure, it is concluded that both factors might act through a common mechanism.

Gastrointestinal disease and oral contraception

Oral contraceptive steroids play a major role in modern family planning. With the present tendency to decrease the doses of both estrogens and progestogens, any factor that reduces the bioavailability of the lower-dose preparations may have an impact on contraceptive protection. Although ethinyl estradiol, the most commonly used oral estrogen, is liable to an enterohepatic circulation as unchanged drug, the commonly used progestogens are not. At present, no convincing evidence exists in the human subject that disruption of the enterohepatic circulation by antibiotics or antacids does reduce contraceptive efficacy of the pill. Oral contraceptive steroids are mainly absorbed from the small bowel, and contraceptive efficacy depends on its absorptive capacity. Enhanced passage of gastrointestinal contents or impaired absorption may thus contribute to contraceptive failures in patients who have chronic inflammatory disease, diarrhea, ileostomy, or jejunoileal bypass.

Lack of association between oral contraceptive use and ulcerative colitis

Previous epidemiological studies suggesting an association between oral contraceptive use and ulcerative colitis incidence have been weak and conflicting. To measure a possible association, 46 incident cases of ulcerative colitis patients, women aged 18-50 years, were compared with peer-nominated age-matched and sex-matched controls. There were no differences between case and control patients in demographic characteristics. There was no association between oral contraceptive use and ulcerative colitis (current use: odds ratio 0.70, 95% confidence interval 0.27-1.83; former use: odds ratio 1.14, confidence interval 0.41-3.15; current or former use: odds ratio 0.86, confidence interval 0.40-1.85). Stratifying by disease location (pancolitis or left-sided disease) also failed to identify an association. Controlling for possible confounding effects of cigarette smoking did not alter the lack of association between oral contraceptive use and ulcerative colitis. Similarly, testing for interaction failed to demonstrate any effect modification. Analyzing for duration of current oral contraceptive use or time interval since last use failed to demonstrate a "dose-response" effect. The study was of sufficient size to detect statistical significance for oral contraceptive use for odds ratios of 2.8 and higher. In this matched case-control study of incident cases and community controls, there was no association between oral contraceptive use and ulcerative colitis incidence. To date, there is no evidence suggesting that women predisposed to the development of ulcerative colitis should be advised to avoid oral contraceptive use.

Lack of association between oral contraceptive use and Crohn's disease: a community-based matched case-control study

Previous epidemiologic studies have suggested a weak association between oral contraceptive use and Crohn's disease, specifically Crohn's colitis. To measure a possible etiologic association, 51 women with Crohn's disease who were 18-50 yr old were studied and compared with peer-nominated age- and sex-matched controls. There were no differences between cases and controls with respect to race, religion, marital status, and number of pregnancies. There was no association between oral contraceptive use and Crohn's disease incidence [current use: odds ratio (OR) 0.73, 95% confidence interval (CI) 0.34-1.59; former use: OR 1.80, CI 0.61-5.29; current or former use: OR 1.00, CI 0.46-2.16]. Stratifying by disease location also failed to identify an association. Cigarette smoking was significantly associated with Crohn's disease incidence. Controlling for possible confounding effects of cigarette smoking did not alter the lack of association between oral contraceptive use and Crohn's disease. Similarly, testing for interaction failed to demonstrate any effect modification. Analyzing for duration of current oral contraceptive use or time interval since last use failed to demonstrate a "dose-response" effect. The study was of sufficient size to detect statistical significance for oral contraceptive use for odds ratios of greater than or equal to 2.76. From this community-based matched case-control study, there was no association between oral contraceptive use and Crohn's disease, and women need not be advised to discontinue oral contraceptive use when a diagnosis of Crohn's disease is made.

Diarrhoea and constipation

Drug-induced constipation is mostly caused by changes in gut motility, whilst diarrhoea is more frequently caused by an increase in intestinal fluid secretion. In both instances the drug has to reach the enteric nervous system or the enterocyte, either via the blood or from the lumen, in sufficient concentrations to affect the mediators that regulate motility and fluid transport. Diarrhoea and constipation are frequently mentioned as side-effects of drugs, and therapeutic agents for almost all organ systems have been implicated. However, both these side-effects are usually mild or moderate, and rarely necessitate interruption of drug treatment. An exception to this rule is the antibiotic-associated colitis seen in patients treated with antibiotics such as lincomycin or clindamycin; in principle almost all antibiotics may cause this severe and potentially life-threatening complication. Other rare forms of severe, drug-induced colitis and diarrhoea result from toxic or anaphylactic reactions against gold preparations, cytostatic agents and sulphonamides. Ischaemic colitis due to vascular complications has been described in some women taking oral contraceptives, and in patients treated with vasopressin or digitalis.

Acute ischaemic colitis in a female long distance runner

A 34 year old female long distance runner is reported with bloody diarrhoea. Colonoscopy revealed patchy haemorrhagic mucosal lesions throughout the colon. The most extensive lesions were found in the sigmoid colon. Histologic examination disclosed mucosal haemorrhage, dilated capillaries, patchy fibrosis and superficial erosions. Additional findings in this patient were haemorrhagic gastritis, microscopic haematuria and rhabdomyolysis. The only medication taken by the patient was oral contraceptives. We conclude that ischaemic colitis is one of the possible mechanisms leading to gastrointestinal blood loss in competitive runners.

Intestinal ischemia and infarction associated with oral contraceptives

Thromboembolic vascular disease is a well-documented complication of oral contraceptive use. In all, 41 cases of mesenteric vascular ischemia or occlusion in women using oral birth control medications have been reported in the literature. “Reversible” ischemic enterocolitis or colitis (15 cases) and intestinal infarction (26 cases) represent the two clinical and pathologic presentations of this infrequently seen complication. Recovery is the rule in transient ischemia; clinically unmistakable intestinal necrosis carries a 31% mortality rate. Several pathophysiologic mechanisms, all unproved, have been proposed to explain these phenomena and the “hypercoagulable state.” Recurrence is rare after the oral contraceptive regimen is discontinued.

Pathogenesis of nonocclusive ischemic colitis

The nonocclusive component of ischemic colitis in anesthetized pigs was mimicked using cardiogenic shock produced by pericardial tamponade. Increases in pericardial pressure produced decreases in arterial pressure (PA) and cardiac output (CO), with corresponding rises in total peripheral resistance (i.e., cardiogenic shock). This was associated with marked reductions in blood flow through the inferior mesenteric artery (IMA), due primarily to disproportionate increases in IMA vascular resistance. Levels of plasma renin activity correlated closely with these changes in mesenteric hemodynamics. Confirmed, total alpha adrenergic blockade with phenoxybenzamine failed to block this selective mesenteric vasoconstriction, while ablation of the renin-angiotensin axis with captopril completely abolished it, thereby ameliorating the colonic ischemia. Central intravenous infusions of pathophysiologic levels of angiotensin II, without tamponade, mimicked the response to shock seen with tamponade alone. In an additional group of pigs, 4 hours of sustained shock (tamponade) followed by 2 hours of normotension (release of tamponade and resuscitation) produced lesions characteristic of ischemic colitis, including full-thickness mucosal ulceration. Such lesions were ameliorated significantly in pigs in which the renin-angiotensin system had been ablated by bilateral nephrectomy. Nonocclusive ischemic colitis appears to be mediated primarily by a remarkable sensitivity of the colonic vasculature to the renin-angiotensin axis.

Evidence for an increased risk of Crohn's disease in oral contraceptive users

The risk of Crohn's disease in relation to oral contraceptive use was evaluated in a hospital-based, case-control study of 57 women with Crohn's disease and 2189 controls with other conditions. The relative risk for oral contraceptive users compared with women who had never used these drugs was 1.9 (95% confidence interval 1.0-3.5). The magnitude of the relative risk estimate was related to the timing and duration of oral contraceptive use. For use within the year before admission to a hospital (recent use), the relative risk estimate was 4.3 (2.1-8.7); the estimate dropped to 1.2 (0.5-2.6) 4 yr after discontinuation of oral contraceptive use. The relative risk estimate for recent use that lasted greater than or equal to 5 yr was 8.0 (3.1-21). The findings are in accordance with earlier reports of an increased risk of Crohn's disease in oral contraceptive users.

Estrogen- and progesterone-associated colitis: a disorder with clinical and endoscopic features mimicking Crohn's colitis

Five women presented with episodes of abdominal pain and bloody diarrhea. Their colonic endoscopic features included (1) rectal sparing, (2) segmental involvement of the colon, and (3) discrete ulcers with normal adjacent mucosa that mimicked Crohn's colitis. All patients were taking estrogen or progesterone or both, and their symptoms and endoscopic findings resolved with cessation of therapy.

Evanescent colitis

Evanescent colitis was first reported in 1971. This clinical entity is manifested by abrupt onset of colicky abdominal pain usually out of proportion to the physical findings, loose stools progressing to hematochezia, and segmental colonic involvement with spontaneous resolution in a matter of days. The diagnosis can be suggested by abdominal flat plate; confirmation depends upon barium-enema examination early in the course of the illness. The clinical presentation is identical to that of colonic ischemia with one remarkable exception: while colonic ischemia has come to be regarded as a disease of the elderly, usually with underlying vascular disease, evanescent colitis occurs in young people who are otherwise free of disease. In this report the authors present nine cases whose course is classic for colonic ischemia except that they are all less than 50 years of age and free of underlying vascular disease. Two of the patients were on oral contraceptive medication. A review of the literature revealed 15 additional cases. Five of these cases were associated with oral contraceptives. Conditions to be excluded in the differential diagnosis of this disease are the specific infectious colitides, idiopathic ulcerative colitis, granulomatous colitis and antibiotic-related pseudomembranous colitis.

Ischemic colitis in young adult patients

A retrospective study of ten patients suggests a possible causal relationship between the thrombogenic properties of estrogen-containing drugs and ischemic colitis, a disease entity believed to be related to occlusion of small blood vessels. We also emphasize that ischemic colitis is a disease limited not only to the elderly, and that it should be included in the differential diagnosis of colitis with bleeding in younger patients.

Drug-induced gastrointestinal disease

The gastrointestinal tract is a common target for adverse drug reactions. The resultant changes are often nonspecific (e.g., mucosal ulceration, intestinal infarction, motility disturbance) and in many cases no radiographically detectable lesion may occur. A comprehensive review of the reported drug-induced disorders of the digestive organs is herein presented and their radiographic manifestations are described.

Ischemic disease of the small bowel and colon associated with oral contraceptives

The widespread use of hormonal contraceptive pills by young women has caused a documented increase in thromboembolic disorders. This article describes yet another of the drug-induced complications namely, the development of ischemic bowel disease in seven cases. The ischemic changes which involved the small intestine in three and the colon in four patients became reversible after conservative management and discontinuance of oral contraceptive agents. The importance of clinical and radiologic consideration of ischemic bowel disease in young females receiving birth control pills is emphasized.

Small bowel ischaemia and infarction in young women taking oral contraceptives and progestational agents

Case histories of three young women who suffered small bowel infarction associated with oral contraceptives and progestational agents are presented. Two infarctions were due to superior mesenteric artery thrombosis and one to superior mesenteric vein thrombosis. All of these patients were of blood group A and smokers, factors which are known to predispose to vascular thrombosis. A study was made of 18 additional cases reported in the literature. It was found that many of these cases presented with a history of symptoms of 2 weeks of more and at operation some of the cases appeared to be reversible. One case was reported where apparent reversion of the process of vascular thrombosis occurred after cessation of the oral contraceptive.

Ischemic disease of the colon and oral contraceptives

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Acute spontaneously recovering ulcerating colitis (ARUC). Report of 6 cases

Six patients each with an extensive ulcerating colitis are reported. Common features were a febrile nonbloody diarrhea; radiological involvement of the whole colon with superficial ulcerations and preservation of haustra, and integrity of the terminal ileum and rectum; the absence of any specific pathological finding; and, most important, the spontaneous recovery of the lesions in the absence of any treatment except sympatomatic measures. The present follow up after recovery range from 18 months to 5 years. Four cases were young women taking oral contraceptives and two patients were older. These patients with colitis could represent a new entity or could be a particular form of Crohn's disease of the colon, with delayed diagnostic pathological features.

Massive intestinal infarction in young women: complication of use of oral contraceptives?

Massive intestinal infarction due to occlusion of the celiac, superior mesenteric and inferior mesenteric arteries occurred in two young women, one of who subsequently died. Both were smokers. They had ingested oral contraceptives for 5 and 8 years, respectively, but this therapy could not be proven to be a causative factor in their ischemic bowel disease; although such an association is uncommon, it should be considered in young women with abdominal pain.

Mesenteric venous thrombosis associated with oral contraceptives: a case report

Small-bowel infarction resulting from mesenteric venous thrombosis is a rare but life-threatening complication to which young women taking oral contraceptives are liable. The patient characteristically presents with an "acute abdomen" after a variable prodromal period of vague abdominal pain. The correct diagnosis can be made from the macroscopic appearance at laparotomy, provided the surgeon is alert to the condition. An accurate diagnosis is important, as anticoagulation measures must be instituted early to counter the commonly associated thromboembolic phenomena.

The inhibitory action of oestradiol-17-beta and progesterone on venous smooth muscle

1 The in vitro action of oestradiol-17-beta (0.1, 1.0 and 10.0 mug/ml) and progesterone (0.1, 1.0 and 10.0 mug/ml) on the spontaneous activity of the portal veins in female rats at different stages of gestation was studied. 2 Progesterone caused the spontaneous mechanical activity in the rat portal vein to decrease in amplitude and increase in frequency. This action was dose-dependent and the sensitivity of the tissue decreased throughout pregnancy. 3 Oestradiol-17-beta had a biphasic effect on spontaneous mechanical activity in the rat portal vein. At 0.1 mug/ml the vessel was stimulated while a similar effect to progesterone occurred with higher concentrations. The tissue was more sensitive to oestradiol at 7 days of gestation than at either the 10-14 or 17-21 day periods of gestation. 4 These effects of oestradiol and progesterone were still seen after blockade of the beta-adrenoceptors. 5 Hydrocortisone (10 mug/ml) had no inhibitory effect on the spontaneous mechanical activity of the vein. 6 The veins from the 17-21 days pregnant animals showed a smaller amplitude of contraction than comparable non-pregnant females.