Taste, Smell Abnormalities Common for IBS Patients

Jie Liu

Patients with functional constipation or irritable bowel syndrome (IBS) often struggle with taste or smell abnormalities, as well as psychological issues like depression or anxiety, according to new research.

A team, led by Jie Liu, Associate Professor Department of Statistics and Finance
University of Science and Technology of China, determined whether taste or smell disturbances and psychological abnormalities are present in patients with functional constipation or irritable bowel syndrome and whether these changes were related to the severity of lower gastrointestinal symptoms.

Background

Psychological abnormalities and decreased eating enjoyment are common for patients with functional constipation and IBS. Patients have also noted changes in the sense of smell and taste, but clinicians have often disregarded this clinically.

The prevalence of chronic gastrointestinal diseases is increasing worldwide, with a recent survey showing 40% of patients with gastroparesis and 60% of patients with gastroesophageal reflux disease (GERD) scoring their taste abnormalities as either mild to moderate or severe to intolerable, respectively.

In the study, the investigators identified 337 patients, 115 of which had functional constipation, 126 patients with IBS, and an additional 96 healthy control participants. Each participant completed questionnaires evaluating their taste and smell, using the taste and smell survey (TSS). Each patient also completed the Lower Gastrointestinal Symptoms Rating Scale (LGSRS), Hamilton anxiety scale (HAMA), and Hamilton depression scale (HAMD).

Correlations

The investigators found taste and smell scores were higher in patients with IBS compared to the healthy control group. In additional lower gastrointestinal scores correlated with taste scores for both patients with functional constipation and IBS (Spearman’s rho = .832; P <0.001).

LGSRS scores also correlated significantly with anxiety (Spearman’s rho = 0.357; (P = 0.017) and depression scores (Spearman’s rho = 0.377; P = 0.012).

Taste scores were also significantly correlated with HAMD scores (Spearman’s rho = 0.479; P = 0.001). However, the smell score significantly correlated with depression scores (Spearman’s rho = 0.325; P = 0.031).

The investigators also found 60.87% and 71.43% of patients complained of taste abnormalities in the functional constipation and IBS groups, respectively. Smell abnormalities were reported slightly higher, with 65.22% of the functional constipation arm and 71.43% of the IBS groups noting smell complaints.

For the psychiatric conditions, 47.83% and 47.62% of patients suffered from anxiety in the functional constipation and IBS groups , while 43.48% of the functional constipation group and 57.14% of the IBS arm suffered from depression.

The final conclusion was there are significant differences in the taste, smell, HAMD, and LGSRS scores between females and male patients with IBS (P <0.050).

“TSCs and psychological disorders are prominent in FC and IBS patients,” the authors wrote. “Taste abnormalities, as well as anxiety and depression, are significantly correlated with LGSRS. Awareness of this high prevalence of taste/smell abnormalities and the psychological changes among patients with FC and IBS may help better predict and understand the severity of symptoms.”

The study, “Subjective Taste and Smell Changes in Conjunction with Anxiety and Depression Are Associated with Symptoms in Patients with Functional Constipation and Irritable Bowel Syndrome,” was published online in Gastroenterology Research and Practice.