Evans J M, Fleming K C, Talley N J, Schleck C D, Zinsmeister A R, Melton L J
Division of Community Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA.
J Am Geriatr Soc. 1998 Jan;46(1):83-7. doi: 10.1111/j.1532-5415.1998.tb01018.x.
The pathophysiology underlying chronic constipation in older people is poorly understood. Our objective was to determine if functional bowel disease (particularly constipation) in this population is associated with risk factors (age, immobility, low dietary fiber intake, and medication use) or directly with slow colonic transit.
A previously validated questionnaire was administered to a random sample of older residents (age range 65-104 years, n = 1609) of Olmsted County, MN. A random subset who met standard diagnostic criteria for functional constipation (n = 52) or irritable bowel syndrome (IBS) (n = 55) and a group without gastrointestinal symptoms (n = 93) were selected for further study. Each subject underwent structured interview and physical examination. Total caloric and fiber intake were assessed by dietitian interview, a food frequency questionnaire, and a food diary. Physical activity was assessed using a previously validated instrument. Medication use was determined by self-report, physician interview, and review of medical records. Total and segmental colonic transit was assessed radiographically using radioopaque markers.
Total colonic transit times were prolonged in subjects with functional constipation (median 50.4 hours) but not in subjects with IBS (median 34.2 hours) or in healthy controls (median 28.8 hours); however, only rectosigmoid transit was delayed significantly. Age, gender, physical activity, and dietary fiber intake were not associated with total transit times, nor could they discriminate among the three patient groups. Laxative use was associated with prolonged total transit times independent of patient group.
Older subjects can be classified by abdominal pain and bowel symptoms, which reflect colonic transit times. Older subjects with constipation symptoms generally have prolonged rectosigmoid transit. Other potential risk factors do not distinguish symptom subgroups, nor are they associated with altered colonic transit although older people who use laxatives regularly have prolonged colonic transit.
老年人慢性便秘的病理生理学机制尚未完全明确。我们的目的是确定该人群中的功能性肠病（尤其是便秘）是否与风险因素（年龄、活动减少、膳食纤维摄入量低及药物使用）相关，或直接与结肠传输缓慢有关。
对明尼苏达州奥姆斯特德县年龄在65 - 104岁的老年居民（n = 1609）进行随机抽样，使用一份先前验证过的问卷进行调查。从符合功能性便秘（n = 52）或肠易激综合征（IBS）（n = 55）标准诊断标准的人群中随机抽取一个子集，并选取一组无胃肠道症状的人群（n = 93）进行进一步研究。每位受试者均接受结构化访谈和体格检查。通过营养师访谈、食物频率问卷和食物日记评估总热量和纤维摄入量。使用先前验证过的工具评估身体活动情况。通过自我报告、医生访谈和病历审查确定药物使用情况。使用不透X线标志物通过影像学方法评估全结肠和节段性结肠传输情况。
功能性便秘患者的全结肠传输时间延长（中位数50.4小时），但IBS患者（中位数34.2小时）和健康对照者（中位数28.8小时）未延长；然而，仅直肠乙状结肠传输明显延迟。年龄、性别、身体活动和膳食纤维摄入量与总传输时间无关，也无法区分这三组患者。使用泻药与总传输时间延长有关，且与患者组无关。
老年受试者可根据腹痛和肠道症状进行分类，这些症状反映了结肠传输时间。有便秘症状的老年受试者通常直肠乙状结肠传输时间延长。其他潜在风险因素无法区分症状亚组，也与结肠传输改变无关，尽管经常使用泻药的老年人结肠传输时间延长。
