Stress and sleep quality in doctors working on-call shifts are associated with functional gastrointestinal disorders

Table 1 Prevalence of irritable bowel syndrome and functional dyspepsia according to the subsets of functional gastrointestinal disorders n (%)

Subtypes of IBS and FD
IBS	28/170 (16.5)
IBS-C	1/28 (3.6)
IBS-D	10/28 (35.7)
IBS-M	16/28 (57.1)
IBS-U	1/28 (3.6)
FD	29/170 (17.1)
EPS	7/29 (24.1)
PDS	10/29 (34.5)
Both EPS and PDS	12/29 (41.4)

IBS: Irritable bowel syndrome; IBS-C: Constipation predominant IBS; IBS-D: Diarrhea predominant IBS; IBS-M: Mixed IBS; IBS-U: Un-subtyped IBS; FD: Functional dyspepsia; EPS: Epigastric pain syndromes; PDS: Postprandial distress syndromes.

Table 2 Baseline characteristics of study subjects according to functional gastrointestinal disorders n (%)

	With FGIDs (n = 48)	Without FGIDs (n = 122)	P value
Age (yr)	27.48 ± 2.70	28.44 ± 3.23	0.069
BMI (kg/m2)	21.80 ± 3.03	21.65 ± 3.79	0.804
Gender (female)	24/48 (50.0)	58/122 (47.5)	0.773
Occupational position (intern)	23/48 (47.9)	43/122 (35.2)	0.300
Marriage (married)	11/48 (22.9)	28/122 (23.0)	0.996
Smoking	3/48 (6.3)	9/122 (7.4)	0.796
Drinking (≥ 1 d/wk)	31/48 (64.6)	54/122 (44.3)	0.292
Working period (yr)	1.35 ± 1.18	1.66 ± 1.35	0.176
Duration of recent on-call work (≥ 2 mo)	39/48 (81.2)	84/122 (68.9)	0.044
Psychosocial alarm (Serious)	40/48 (83.3)	69/122 (56.6)	0.004
Length of sleep (h)	5.35 ± 0.86	5.48 ± 0.86	0.377
Sleep quality score (PSQI)	8.79 ± 2.71	7.30 ± 3.43	0.008
Poor sleeper (PSQI ≥ 6)	43/48 (89.6)	81/122 (66.4)	0.002

FGIDs: Functional gastrointestinal disorders; PSQI: Pittsburgh Sleep Quality Index; Data presented as mean ± SD.

Table 3 Prevalence of irritable bowel syndrome and functional dyspepsia according to the sleep quality n (%)

	PSQI < 6	PSQI ≥ 6	P value
	(Non-poor sleeper)	(Poor sleeper)
	(n = 46)	(n = 124)
IBS	3/46 (6.5)	25/124 (20.2)	0.033
FD	2/46 (4.3)	27/124 (21.8)	0.007

IBS: Irritable bowel syndrome; FD: Functional dyspepsia; PSQI: Pittsburgh sleep quality index.

Table 4 Prevalence of functional gastrointestinal disorder according to the psychosocial alarm n (%)

	Alarm absent (n = 37)	Alarm present (n = 24)	Alarm serious (n = 109)	P value
IBS	4/37 (10.8)	3/24 (12.5)	21/109 (19.3)	0.416
FD	2/37 (5.4)	1/24 (4.2)	26/109 (23.9)	0.007

IBS: Irritable bowel syndrome; FD: Functional dyspepsia.

Table 5 Risk factors for functional dyspepsia in univariate and multivariate analysis

	Univariate analysis		P value	Multivariate analysis		P value
	OR	95%CI		OR	95% CI
Age (yr)	0.91	0.79-1.03	0.136	1.166	0.96-1.42	0.131
Sex (female)	2.35	1.02-5.42	0.045	2.07	0.77-5.58	0.151
BMI (kg/m2)	1.00	0.96-1.02	0.686
Occupational position
Intern	Reference			Reference
Resident	0.37	0.16-0.85	0.019	0.28	0.12-0.68	0.005
Fellow	0.48	0.05-4.28	0.511	1.42	0.12-17.58	0.783
Marriage	2.18	1.05-3.36	0.001	2.73	1.08-6.39	0.039
Smoking	0.33	0.15-2.33	0.099	3.07	0.610-15.45	0.174
Drinking (≥ 1 d/wk)	2.38	1.02-3.60	< 0.0001	5.96	1.08-10.22	0.025
Duration of recent on-call work (mo)	0.32	0.28-0.67	0.001	0.64	0.31-2.94	0.076
Psychosocial alarm
None	Reference			Reference
Present	0.76	0.07-8.88	0.827	0.69	0.05-9.11	0.780
Serious	5.48	1.23-24.36	0.025	5.47	1.06-28.15	0.042
Length of sleep (h)	0.88	0.56-1.43	0.453
Poor sleep quality (PSQI ≥ 6)	0.28	0.04-0.72	< 0.0001	1.10	0.47-1.36	0.076
Working period (yr)	0.94	0.69-1.28	0.690

For the occupational position, the intern is the reference group. For the psychosocial alarm, the absence of psychosocial alarm is the reference group. BMI: Body mass index; PSQI: Pittsburgh Sleep Quality Index; OR: Odds ratio.

Table 6 Risk factors for irritable bowel syndrome in univariate and multivariate analysis

	Univariate analysis			Multivariate analysis
	OR	95%CI	P value	OR	95%CI	P value
Age (yr)	0.92	0.81-1.06	0.239	1.03	0.88-1.20	0.696
Sex (female)	0.54	0.23-1.25	0.151	2.33	1.25-14.00	0.020
BMI (kg/m2)	1.00	0.97-1.01	0.206
Occupational position
Intern	Reference			Reference
Resident	0.99	0.43-2.29	0.977	4.29	1.25-14.73	0.021
Fellow	0.87	0.09-7.63	0.872	2.29	0.95-3.90	0.460
Marriage	1.19	0.45-2.94	0.778
Smoking	0.42	0.05-3.38	0.411
Drinking (≥ 1 d/wk)	0.79	0.58-3.14	0.478
Duration of recent on-call work (mo)	0.92	0.88-2.78	0.125	1.45	0.40-5.26	0.576
Psychosocial alarm
None	Reference			Reference
Present	1.18	0.24-5.80	0.840	1.81	0.44-4.62	0.817
Serious	1.97	0.63-6.17	0.245	1.53	0.42-5.64	0.523
Length of sleep (h)	1.11	0.45-1.17	0.934
Poor sleep quality (PSQI ≥ 6)	3.16	1.04-12.63	0.002	4.17	1.92-19.02	0.016
Working period (yr)	0.72	0.51-1.02	0.601

For the occupational position, the intern is the reference group. For the psychosocial alarm, the absence of psychosocial alarm is the reference group. BMI: Body mass index; PSQI: Pittsburgh Sleep Quality Index; OR: Odds ratio.