Table 3. 4-year cumulative dental care days and costs for different BMI and metabolic phenotypes.

	Underweight		Normal weight		Overweight		Obesity		P valuea
	(BMI <18.5)		(BMI 18.5–24.9)		(BMI 25.0–29.9)		(BMI ≥30.0)
	Healthy	Unhealthy	Healthy	Unhealthy	Healthy	Unhealthy	Healthy	Unhealthy
	(n = 664)	(n = 54)	(n = 8,465)	(n = 2,461)	(n = 2,082)	(n = 1,888)	(n = 282)	(n = 490)
Inpatient days, days/person/year
Adjusted mean	0.003	0.000	0.004	0.003	0.006	0.000	0.001	0.019	0.203
(95% CI)	(−0.006 to 0.013)	(−0.032 to 0.032)	(0.001 to 0.007)	(−0.002 to 0.008)	(0.001 to 0.011)	(−0.006 to 0.006)	(−0.013 to 0.016)	(0.008 to 0.030)
Median	0	0	0	0	0	0	0	0	0.938
(interquartile range)	(0–0)	(0–0)	(0–0)	(0–0)	(0–0)	(0–0)	(0–0)	(0–0)
Outpatient days, days/person/year
Adjusted mean	2.7	3.8	2.9	2.9	2.9	3.0	2.9	3.0	0.383
(95% CI)	(2.4–3.0)	(2.8–4.7)	(2.9–3.0)	(2.7–3.0)	(2.7–3.0)	(2.8–3.1)	(2.5–3.3)	(2.7–3.3)
Median	1.3	2.6	1.8	2.3	1.8	2.3	1.5	1.8	<0.001
(interquartile range)	(0–3.3)	(0.4–7.3)	(0.3–4.0)	(0.3–5.0)	(0.1–4.0)	(0.3–5.0)	(0–4.3)	(0–4.5)
Costs, 1,000 JPY/person/yearb
Adjusted mean	18	27	19	19	19	19	20	21	0.081
(95% CI)	(16–20)	(21–33)	(19–20)	(18–20)	(18–20)	(18–21)	(17–22)	(19–23)
Median	9	17	11	15	11	15	10	13	<0.001
(interquartile range)	(0–23)	(2–48)	(1–26)	(2–33)	(0–27)	(2–34)	(0–28)	(0–30)

BMI, body mass index; CI, confidence interval, JPY, Japanese yen.

^aP values for differences among 8 phenotypes were adjusted for age, smoking status, frequency and amount of alcohol intake, exercise habits, daily sleeping hours, and treatment of hypertension, dyslipidemia, or diabetes.

^bCost unit is expressed as 1,000 JPY (1,000 JPY = 8.8 US dollars or 7.8 euros, according to foreign exchange rates on Dec 6, 2018).