Functional Constipation in Older Adults: Prevalence, Clinical Symptoms and Subtypes, Association with Frailty, and Impact on Quality of Life

<b><i>Introduction:</i></b> Functional constipation (FC) is very prevalent in older adults, especially in women, but its relationship with frailty is not fully understood. The aims were to assess FC prevalence, clinical symptoms and subtypes, association with frailty, and impact on quality of life (QoL) in older people. <b><i>Methods:</i></b> This epidemiological study included 384 individuals aged over 70 years recruited from the community, a hospital, and a nursing home and stratified into robust, pre-frail, and frail groups (Fried criteria). The following criteria were evaluated: frailty, FC (Rome III criteria), stool consistency (Bristol Stool Chart), comorbidities (Charlson), dependency (Barthel), QoL (EQ5D), and clinical and sociodemographic data. Defined by symptom aggregation were 2 main clinical subtypes as follows: slow colonic transit time (CTT) and functional defecation disorder (FDD). <b><i>Results:</i></b> Mean age was 79.11 ± 6.43 years. Overall FC prevalence was 26.8%, higher in women (32.4% women vs. 21.8% men; <i>p</i> = 0.019) and highest in frail patients (41.7% frail vs. 33.9% pre-frail vs. 24.2% robust; <i>p</i> &#x3c; 0.001). Straining and hard stools (Bristol 1–2) were the most prevalent symptoms (89.3 and 75.7%, respectively). Frailty and benzodiazepine intake were independently associated with FC. Patients with FC obtained poorer QoL scores in the EQ5D (perceived health 66.09 ± 17.8 FC patients vs. 56.4 ± 19.03 non-FC patients; <i>p</i> &#x3c; 0.05). The FDD subtype became significantly more prevalent as frailty increased (6.5, 25.8, and 67.7% for robust, pre-frail, and frail patients, respectively); the slow CTT subtype was significantly more frequent in robust patients (38.5% robust vs. 30.5% pre-frail vs. 23.1% frail), <i>p</i> = 0.002. <b><i>Discussion/Conclusion:</i></b> FC prevalence in older adults was high, especially in women, and was associated with frailty and poor QoL. Clinical subtypes as related to frailty phenotypes reflect specific pathophysiological aspects and should lead to more specific diagnoses and improved treatment.