A prospective 5-year study of trismus prevalence and fluctuation in irradiated head and neck cancer patients

Figures & data

Table 1. Sociodemographic and clinical characteristics for study participants n = 211.

	Mean, 95% CI
Age	61.0 (60–62)
Karnofsky Performance Scale^a	97.5 (97–98)
BMI whole cohort	26.6 (26–27)
	n (%)
BMI
<18.5	3 (1)
18.5–25	68 (33)
>25	139 (66)
Missing = 1
Gender
Male	157 (74)
Female	54 (26)
Living alone
No	153 (73)
Yes	58 (27)
Number of school years
6–9 years	58 (27)
9–12 years	99 (47)
>12 years	54 (26)
Employment
Full time	98 (46)
Part time	16 (8)
Unemployed	8 (4)
Old age pensioner	70 (33)
Early retiree	19 (9)
Smoking
Yes	49 (23)
No	162 (77)
Dental status
Normal	204 (97)
Prosthesis upper jaw	2 (1)
Prosthesis lower jaw	1 (0.5)
Prosthesis upper + lower	4 (1.5)
jaw
Tumor stage
I	8 (4)
II	36 (17)
III	49 (23)
IV	118 (56)
Tumor site
Oral cavity	34 (16)
Oropharynx	132 (62)
Salivary gland	8 (4)
Nasopharynx^b	16 (8)
CCUP	21 (10)
Cancer treatment
RT Only	45 (21)
CRT	131 (62)
RT/CRT + surgery	35 (17)
ACE27
No comorbidity	92 (43)
Mild comorbidity	76 (36)
Moderate comorbidity	35 (17)
Severe comorbidity	8 (4)

ACE27: Adult Comorbidity Evaluation 27; BMI: Body Mass Index; CCUP: Cervical Carcinoma of Unknown Primary; CRT: Chemoradiotherapy; CI: Confidence Interval; RT: Radiotherapy. ^aRange from 0–100 equals perfect health. ^bIncludes cancer of the nasal cavity and paranasal sinuses.

Table 2. MIO and trismus in the study population up to 5 years post-radiotherapy.

	Baseline	3 months post-RT	6 months post-RT	12 months post-RT	24 months post-RT	36 months post-RT	60 months post-RT
	n = 211	n = 199	n = 189	n = 180	n = 166	n = 140	n = 129
Mean	51.5	42.4	41.4	41.7	41.2	41.3	41.3
95 % CI Median Range	(51–52)	(41–44)	(40–43)	(40–43)	(40–43)	(40–43)	(40–43)
	52.0	42.0	40.0	40.0	40.0	40.5	40.0
	36–73	15–70	18–65	19–63	13–62	20–60	20–60
Trismus
Yes (%)	0 (0)	61 (31)	63 (33)	49 (27)	42 (25)	35 (25)	36 (28)
No (%)	211 (100)	138 (69)	126 (67)	131 (73)	124 (75)	105 (75)	93 (72)

MIO: Maximum interincisal opening; CI: Confidence Interval.

Table 3. Mean (95% CI) change in MIO in millimetres and percent at each time-point compared to baseline.

			p Value	p Value
Time-point	Δ in mm	Δ in %	% Δ from baseline	% Δ from preceding follow-up
3 months	−9.1 (−10–8)	−17.4 % (−19–15)	<.001	–
6 months	−10.0 (−11–9)	−19.3 % (−21–17)	<.001	<.001
12 months	−10.1 (−11–9)	−19.3 % (−21–17)	<.001	.94
24 months	−10.4 (−12–9)	− 19.7 % (−22–17)	<.001	.23
36 months	−10.6 (−12–9)	−20.0% (−22–18)	<.001	.61
60 months	−10.6 (−12–9)	−19.9% (−23–17)	<.001	.26

CI: Confidence Interval; MIO: Maximum interincisal opening.

Figure 1. Percentage of patients with a change in MIO compared to the previous time-point. *a statistically significant change (p < 0.05) compared to the preceding time-point.

Table 4. Change from baseline when divided into MIO ≤ 35 mm and > 35 mm.

	3 months post-RT		6 months post-RT		12 months post-RT		24 months post-RT		36 months post-RT		60 months post-RT
	MIO ≤ 35	MIO > 35	MIO ≤ 35	MIO > 35	MIO ≤ 35	MIO > 35	MIO ≤ 35	MIO > 35	MIO ≤ 35	MIO > 35	MIO ≤ 35	MIO > 35
n =	61	138	63	129	49	131	42	124	35	105	36	93
Mean mm	32.3	46.9	32.9	45.7	31.3	45.5	30.1	45.0	30.7	44.8	30.4	45.5
95% CI	31–33	46–48	32–34	45–47	30–33	44–48	28–32	44–46	29–32	44–46	29–32	44–47
Median mm	35.0	46.5	35.0	45.5	33.0	45.0	32.0	44.5	33.0	44.0	32.0	45.0
Range mm	15–35	37–70	18–35	36–65	19–35	36–63	13–35	36–62	20–35	36–60	20–35	36–60
Δ from baseline mm	−15.8	−6.1^a	−16.0	−7.1^a	−16.9	−7.6^a	−18.5	−7.7^a	−18.2	−8.1^a	−18.9	−7.3^a
Δ 95% CI	−18–−13	−7–−5	−18–−14	−8–−6	−19–−14	−9–−7	−21–−16	−9–−7	−21–−16	−9–−7	−22–−16	−9–−6
Δ from preceding follow-up	–	–	−3.2	−0.6^a	−2.2	0.6^a	−2.9	0.3^a	−0.4	0	−1.4	−0.1^a
Δ 95% CI	–	–	−5–−1	−1–0	−4–−1	0–1	−5–−1	−0.3–1	−2–1	−0.4–0.4	−3–−0.1	−1–1

CI 95%: Confidence interval; MIO: Maximum interincisal opening; RT: Radiotherapy.

^aStatistically significant difference between the groups with p < .05.